2018 School of science - RMIT University€¦ · School of Science HDR Project 2018 . Overcoming...

Bioscience DR231/ MR231

Food Technology DR232/ MR232

— 2018 School of science HDR Research Projects

Contents Click on the project links for more information

Biosciences

Professor Dayanthi Nugegoda • Health of the endangered Burrunan dolphin (Tursiops australis)in Victoria: ecotoxicology and stress

assessment• Mixture toxicity assessment of pharmaceuticals released into urban waterways

Professor Ian Macreadie • Overcoming reduced proteostatis in ageing with a systems biology approach

Professor Robert Moore • Isolation and Characterisation of “New Generation” Probiotic Bacteria

Associate Professor Jeff Shimeta • Larval Settlement of Marine Biofouling Invertebrates• Roles of Benthic Invertebrates in the Sequestration and Mobilisation of Heavy Metal Contaminants in the

Gippsland Lakes

Dr Nathan Bott • Improving management of Southern Bluefin tuna health• Molecular approaches to understanding Victorian zooplankton communities

Dr Nittin Mantri • Development and characterization of honey-based products for treating atherosclerosis• Identification and validation of candidates for stress tolerance in chickpea• Management of plant pathogens using next generation nano-sensors

Dr Paul Ramsland • Mapping the structural and antigenic features of viral envelope glycoprotein assemblies• Harnessing carbohydrate-based informatics (glycoinformatics) to develop biosensors for surveillance of

cancer and infection

Dr Ravi Shukla • Nanochip biosensor for assessment of endothelial cell damage in diabetes• Metal Organic Framework based non-viral vectors for targeted knockdown of telomerase gene in prostate

cancer

Dr Taghrid Istivan • Virulence and colonization of Campylobacter concisus in the gastrointestinal tract environment in relation to

other gut microbes• Cellular mechanisms of bioactive compound release to develop effective drug delivery systems

Dr Tien HuynhInvestigation on the plant dynamics and fungal variability between remnant, translocated andreintroduced populations of Caladenia amoena (Orchidaceae)

•

Professor Aidyn Mouradov

• Microalgal-Based production of oral vaccines, therapeutic proteins and added value products• Characterization of Australian Bioluminescent Dinoflagellates

Food Technology

Professor Stefan Kasapis • Understanding the Molecular Origin of Interactions between Dairy Proteins and Phenolic Compounds• Stimuli responsive on-off switching in bioactive compound release from high-solid biopolymer systems

Associate Professor Benu Adhikari • Developing super hydrophobic biodegradable packaging films mimicking lotus effect• Overcoming obesity through synergistic combination of Roselle hydroxycitric acid (HCA) and Roselle

polyphenols

Dr Bogdan Zisu • Compositional and Functional Stability of Thermally and Mechanically Processed Camel Milk• Understanding the Effects of Low Frequency Ultrasound on the Oxidative Stability of Milk Fat and Protein

Solutions

Dr Jayani Chandrapala • Valorization of dairy waste streams• Functionality Modifications of Milk and Milk Products

DR231 – PhD (Applied Biology/Biotechnology) MR231 – Master of Science (Applied Biology/Biotechnology)

School of Science HDR Project 2018

Health of the endangered Burrunan dolphin (Tursiops australis)in Victoria: ecotoxicology and stress assessment

BioSciences and Food Technology Discipline/Ecotoxicology Research Group, Centre for Environmental Sustainability and Remediation – RMIT Bundoora West

Project Description Coastal marine and estuarine ecosystems are seeing a decline in health on a world-wide scale as a result of increased anthropogenic pressures (Cagnazzi et al., 2013). These pressures include increased coastal human population resulting in changing land use, industrial development and urbanisation, all of which can lead to an increase in pollutant discharge. Inshore cetaceans, such as the Burrunan dolphin (Tursiops australis), are particularly vulnerable, since they are top order predators with high site fidelity, and a long life span with large fat stores which accumulate pollutants as they biomagnify up the trophic food chain.

PCBs and PAHs as well as mercury have been suggested to be related to mass mortality and population decline of some cetacean species, as a result of impaired reproductive success and immune defence (Taddei et al., 2001). The Burrunan dolphin has been found to contain some of the highest recorded mercury levels among all cetaceans worldwide (Monk et al., 2014), with beach-cast deceased individuals recording levels three times higher than those in the live population (Monk et al., 2014). However, to date there has been no analysis on the health of these animals, and therefore we cannot draw conclusions on the effects of the high but sub-lethal concentrations of mercury, nor the effect of organic pollutants on the animals.

The use of cetacean skin biopsies is a non-lethal method for collecting tissue and blubber with minimal impact to the animals. The tissue sample can be used the conduct both Comet Assays and test MICA protein expression to investigate the effects of pollutants on the health of the animal. The Comet Assay or single cell gel electrophoresis (SCGE) is a sensitive and rapid method for measuring DNA damage in individual cells (Dhawan et al. 2009) . The evaluation of MICA protein expression assess the status of the immune system, as a reduction in immune proteins in cetaceans is an indicator of stress from pollutants (Marsili et al., 2010, Fossi and Marsili, 2011). In order to trace the route of bioaccumulation, the blubber sample can be used to investigate the diet of the animal.

This project will aim to • Assess health of the Burrunan dolphins, investigating the genotoxicity of heavy metals and organic pollutants(using COMET assays) and stress from pollutants (via MICA protein expression).• Investigate the diet of the Burrunan dolphins residing in Port Phillip Bay and the Gippsland Lakes, to establish theroute of bioaccumulation of toxicants within the animals.

Specific or specialist training required: Training in sampling live dolphin tissue will be provided by co-supervisor Dr Kate Charlton- Robb of the Australian Mammal Conservation Foundation. All ethics permits have been obtained by the co-supervisor from the Australian Marine Mammal Foundation and will be provided for approval to the RMIT Animal Ethics Committee

References [1]. Dhawan A, Bajpayee M, Parmar D. (2009) Comet assay: a reliable tool for the assessment of DNA damage in different models. Cell Biology and Toxicology 299(25) 5-32. [2] Fossi MC, Marsili L.(2011) Multi-Trial Ecotoxicological Diagnostic Tool in Cetacean Skin Biopsies. In: UdayKhopkar (ed.) Skin Biopsy – Perspectives. Rijeka: InTech; 2011. p317- 333.[3] Marsili L, Maltese S, Carletti L, Coppola D, Casini S, Fossi MC.(2010) MICA expression as toxicological stressmarker in fibroblast cell cultures of cetaceans. Comparative Biochemistry and Physiology - Part A: Molecular &Integrative Physiology 2010;157(1) S24-S25.

Contact Details 1st Supervisor – Professor Dayanthi Nugegoda email: [email protected] (03) 9925-7150 2nd Supervisor– Dr Kate Charlton-Robb, Marine Mammal Foundation email: [email protected]

mailto:[email protected]



Mixture toxicity assessment of pharmaceuticals released into urban waterways.

BioSciences and Food Technology Discipline/Ecotoxicology Research Group, Centre for Environmental Sustainability and Remediation – RMIT Bundoora West

Project Description

In aquatic ecosystems, exposure to mixtures of toxic chemicals resulting from human activities is the norm, and assessing the biological effects of chemical mixtures remains an enduring challenge in the field of ecotoxicology. It is expected that global climate change will influence the fate and bioavailability of chemicals. Two other issues with regard to the application of guidelines are the effect of toxicant pulses (e.g. discharge or seasonal controls) and alternating geochemical environments (e.g. redox changes controlled by seasonal, climate variability, climate change which often control bioavailability/toxicity), which are needed to assess the impact and risks of contaminants on ecosystems.

More studies are needed to better characterise the interactive effects of chemical contaminants and abiotic stressors related to climate change. There is a lack of environmental realism, as most part of our current knowledge about the applicability of the concepts is restricted to simplified situations with respect to mixture composition and biological effect assessment. Thus, it is unknown so far whether the good agreement of observed mixture toxicities with pharmacologically based predictions still holds, when environmentally relevant mixtures and bioassays with organisms with different routes of contaminant uptakes and different life histories are considered. This is one of the key knowledge gaps that was identified in the guidelines and needs to be addressed. The ecotoxicological consequences of incomplete removal of pharmaceuticals or their metabolites in wastewater or drinking water treatment plants is still an environmental concern and requires further research

The objective of the proposed study is

• To quantify and assess the hazard and risk that a given pharmaceutical mixture poses for theenvironment.

• To identify which pharmaceuticals are the ecotoxicological drivers at a given site• To quantify and assess the hazard and risk that a given pharmaceutical mixture poses for the

environment.• To predict which pharmaceutical mixtures, in terms of composition and concentration, can be

tolerated in a given environmental compartment

Specific or specialist training required: None. However please note that the candidate will be based at the CSIRO labs in Glen Osmond, South Australia for a proportion of their candidature. All ethics permits have been obtained by the co-supervisor from the CSIRO Land and Water, Glen Osmond, South Australia and will be provided for approval to the RMIT Animal Ethics Committee

References [1]. Bal, N., Kumar, A., Du, J., Nugegoda, D., 2016. Prednisolone impairs embryonic and post hatching development and shell formation of the freshwater snail, Physa acuta. Environ. Toxicol. Chem. 35(9):2339-48 [2]Bal, N., Kumar, A., Du, J., Nugegoda, D., 2017. Multigenerational effects of two glucocorticoids (prednisolone anddexamethasone) on life-history parameters of crustacean Ceriodaphnia dubia (Cladocera). Environ. Pollut. (In press)Available online 21st March 2017 http://dx.doi.org/10.1016/j.envpol.2017.03.024

Contact Details

1st Supervisor – Professor Dayanthi Nugegoda email: [email protected] (03) 9925-7150 2nd Supervisor– Dr Anu Kumar, Group Leader- Contaminant Biogeochemistry and Environmental Toxicology,CSIRO Land and Water (08) 8303 8597 email: [email protected]

http://dx.doi.org/10.1016/j.envpol.2017.03.024




Overcoming reduced proteostatis in ageing with a systems biology approach

BioSciences and Food Technology Discipline – RMIT Bundoora West

Project Description

This project will utilize yeast expressing deleterious proteins, such as amyloid beta, that accumulate with ageing in humans and in yeast. The ageing in yeast will be assayed in a systems biology approach to examine ways in which proteostasis can be improved in aging cells.

A substantial contributor to ageing is a decline in proteostasis. The impact of this is particularly obvious in the brain and neuronal cells where loss of function and cell death may result from the lack of clearance of proteins. The Alzheimer's amyloid beta protein accumulates with age and its toxicity is associated with neuronal death. In yeast it can be observed that amyloid beta also accumulates with age and is toxic. Studies of GFP-labelled amyloid beta in yeast have provided a convenient opportunity to study cellular mechanisms to overcome toxicity and to study compounds that overcome toxicity [1,2]. Increasing autophagic turnover of proteins is one mechanism to reduce problematic proteins of ageing. Some compounds enable old cells to do this more effectively, and it is of interest to examine ingredients in foods that may also act in this manner. It can be inferred that improving proteostasis will delay the incidence of Alzheimer's disease, Parkinson's disease, and possibly other diseases where the accumulation of toxic proteins is highly deleterious to the brain.

References

[1] Porzoor and Macreadie. Systems biology of Alzheimer’s disease: Methods and protocols. (Castrillo JI andOliver SG ed.), Humana Press Ch 12: 217-226 (2015).[2] Porzoor et al. Biomolecules 5: 505-527 (2015).

Contact Details

To discuss this project further please contact: 1st Supervisor –Prof Ian Macreadie, Bundoora 223.1.28C 2nd Supervisor – A/Prof Benu Adhikari, Bundoora 201.6.5



Isolation and Characterisation of “New Generation” Probiotic Bacteria

Biosciences & Food Technology Discipline,/ Host-Microbe Interactions Group – RMIT Bundoora

Project Description

Probiotics are live microorganisms that have health benefits for the host [1]. In this project, our aim is to identify and develop a new generation of probiotic bacteria that are better able to colonise, establish and grow within the complex and variable microbial environment of the gastrointestinal tract (GIT) than existing probiotics. Our development of methods to identify and develop such superior probiotics is being done in the context of use within the poultry production industry but can also be adapted to develop probiotics for other animals and humans.

The poultry industry is the most efficient producer of meat and this is important in maintaining global food security. The efficiency of the industry is enhanced by products that support the health and productivity of birds. Probiotics are one class of product that can be used for this purpose. Probiotics have been used to promote gut health in humans and animals for many years. However, there are several issues of concern with current probiotics. For example, their effectiveness can be quite variable and continuous dosing is usually required. A new generation of probiotic products, with better characteristics, could overcome these limitations.

The primary goal of the PhD project will be to isolate spore forming bacteria with probiotic properties. Bacterial spores are an excellent choice for probiotics as they can survive the harsh environment of the upper section of the chicken GIT and germinate in the intestines where, in concert with the host microbiota, they can exert positive effects. We have previously noted that normal bench-based isolation methods only detect a small percentage of the diverse bacterial types that we know inhabit the gut. We will, therefore, employ more advanced culturing methods, such as strictly anaerobic conditions and different growth substrates, in an attempt to isolate a wider variety of novel bacterial strains for screening as probiotics.

In addition, we will develop new and more robust ways to screen collections of bacteria for probiotic potential. Traditionally, a number of in vitro tests, such as acid and bile resistance, adherence to cultured cells, and aggregation ability, have been used as preliminary screening mechanisms for probiotic identification. However, the value of these tests has never been fully evaluated and our preliminary data indicates that they may be unreliable guides to how strains actually perform in the GIT. Direct methods of in vivo screening, supported by next generation sequencing analysis of gut microbiota, will be developed as a more direct and reliable method of identifying new probiotic strains.

Learning outcomes

The PhD candidate will be mentored to develop critical thinking and a rigorous scientific approach to problem solving. They will learn advanced skills in bacterial isolation and molecular characterisation; next generation sequencing and bioinformatics; animal handling and trial work; and generally skills in literature searching and review, writing, publication and presentation.

Reference

[1] Johnson & Klaenhammer. (2014) Impact of genomics on the field of probiotic research: historicalperspectives to modern paradigms. Antonie van Leewenhoek 106:141-156.

Contact Details

To discuss this project further contact: Professor Robert Moore ([email protected]) Dr Hao Van ([email protected])



DR231 – PhD (Applied Biology & Biotechnology) MR231 – Master of Science (Applied Biology & Biotechnology)


Microalgal-Based production of oral vaccines, therapeutic proteins and added value products

Applied Biology and Biotechnology – Bundoora campus

Project Description

The World Health Organization (WHO), the National Institutes of Health, UNESCO and several other agencies have stressed the need for a new generation of low-cost vaccines and human protein therapeutics for the poorest regions of the world. They especially emphasized the need for (i) oral administration of vaccines and therapeutics; ii) heat-stable to avoid the considerable expense in maintaining the cold-chain during production and distribution and (iii) needle-free formulations to eliminate the risk of opportunistic contamination as well as the need for qualified personnel. Over the last few years, microalgae have gained increasing interest as a natural source of valuable compounds and as bioreactors for recombinant protein production. The photosynthetic unicellular alga Chlamydomonas reinhardtii represents a cost-effective alternative to plant, microbial and animal cell factories for the production of clinically useful proteins. The rigid microalgal cell wall protects the antigen from rapid degradation in the acidic environment of the stomach. Furthermore, in contrast to current syringe-injected vaccines, oral administration of algal tissues elicits systemic as well as mucosal immune responses. Algal-derived products are inexpensive with protein production levels as high as 2-5 mg protein/ litre of cells achieved at a relatively low cost (<$l/mg protein). Also, microalgal produced antigens do not need to be isolated and purified. Production of recombinant proteins in C. reinhardtii chloroplasts, which occupy about 60% of the cell volume, allows expression and accumulation of recombinant proteins to very high levels, mainly because plastids lack gene silencing mechanisms and other mechanisms that reduce recombinant protein production from nuclear-encoded genes. Prof Aidyn Mouradov has over 30 years’ experience in genetic modification of plants to improve their health, productivity and adaptation to the environment (over 50 research papers and 25 international patents). Since 2011 his group is successfully working on the application of algal biomass for production of added value chemicals: DHA and EPA, proteins, carbohydrate, antioxidants widely used for bioenergy and human and animal health improvement. Extensive research was also targeted expression of antigens in microalgae to produce edible vaccines against influenza, West Nile Virus, Shrimp White Spot Virus. The primary goal of the PhD/master project will be to express codon-optimised synthetic version of antigens or human therapeutics protein in nuclear and chloroplast genome of the Chlamydomonas reinhardtii with a targeted accumulation of proteins in chloroplasts, cytoplasm, endoplasmic reticulum and vacuole.

References

1. Plant Physiology and Biochemistry, 124 (2018) 117–125; 2;2. Mol Breeding (2018) 38:21; Biotechnology for Biofuels, (2017) 10:1, 120;3. Biotechnology for Biofuels, (2016) 9:21;4. Biotechnology for Biofuels, 8:179;5. Current Biotechnology, (2015) Vol. 4, No. 4; Frontiers in Plant Sciences, (2014), 5:620;6. PLoS ONE, (2014)9(11):e113497.7. Biotechnology for Biofuels, 7(1):30-39.

Contact Details

To discuss this project further please contact: Professor Aidyn Mouradov ([email protected])

DR231 – PhD (Applied Biology & Biotechnology) MR231 – Master of Science (Applied Biology & Biotechnology)


Characterization of Australian Bioluminescent Dinoflagellates

Applied Biology and Biotechnology – Bundoora campus

Project Description – Bioluminescence, the emission of light by a living organism, is one of the most spectacular natural events observed on Earth and has inspired artists and scientists for thousands of years. The fact that bioluminescence has evolved independently at least 27 times in 17 major marine species over the last 150 million years reveals how important this phenomenon is for living creatures, helping them in different life situations such as attraction, warning, mimicry and defence. On a molecular level, bioluminescence is triggered by oxidation of the light-emitting chemical, luciferin. This reaction is catalysed by an enzyme called luciferase. One of the most spectacular forms of bioluminescence is produced by tiny marine microorganisms, Dinoflagellates. In the sea, light emission by trillions of these unicellular organisms is mostly seen when cells are mechanically stimulated, either at the surface of waves, by swimming animals or humans, or by vessels (see https://www.youtube.com/watch?v=qlTCB_p3slY). Over last few decades Dinoflagellate-produced bioluminescence has attracted the attention of researchers working in defence science, such as for the air force and navy. The shining plankton disturbed by moving objects can be spotted from the surface. The fact that bioluminescence is the only known source of light on Earth that is cold (producing practically no heat) is also of great interest. Over the last decade, the US Air Force and Navy have granted millions of dollars to academic institutions to investigate how to use bioluminescence to their advantage.

This project is collaboration between RMIT and Defence Science and Technology Group of the Australian military and aims to understand the molecular diversity of the Dinoflagellates that thrive at seas of Northern Australia. The project will also involve an extensive research targeted on understanding of molecular aspects of bioluminescence in Dinoflagellates and pathways triggering it in response to environmental factors.

References 1. Plant Physiology and Biochemistry, 124 (2018) 117–125; 2;2. Mol Breeding (2018) 38:21;3. Biotechnology for Biofuels, (2017) 10:1, 120;4. Biotechnology for Biofuels, (2016) 9:21;5. Biotechnology for Biofuels, 8:179;6. Current Biotechnology, (2015) Vol. 4, No. 4;7. Frontiers in Plant Sciences, (2014), 5:620; PLoS ONE, (2014)9(11):e113497.8. Biotechnology for Biofuels, 7(1):30-39.

Contact Details: To discuss this project further please contact:

Professor Aidyn Mouradov ([email protected])



Larval Settlement of Marine Biofouling Invertebrates

Biosciences and Food Technology Discipline/Centre for Environmental Sustainability & Remediation – RMIT Bundoora West

Project Description

Marine biofouling is the accumulation of living organisms on artificial surfaces in the ocean that has undesired ecological and/or economic consequences, such as fouling of ship hulls and underwater infrastructure. Biofouling is composed of numerous species of bacteria, protists, invertebrates, and exudates. The nature and development of fouling vary greatly among types of surfaces, locations, and seasons. Studies of the settlement mechanisms and interactions among fouling organisms are needed to better understand the fundamental ecology of marine epifaunal dynamics and to guide research on antifouling technologies.

Much recent research has focused on interactions between settling invertebrate larvae and microbial biofilm organisms that serve as cues for settlers, either stimulating or suppressing settlement. This project will investigate mechanisms by which larvae respond to cues from biofilm microbes (considering species assemblages of bacteria and protists), ultimately influencing settlement rates and species succession as biofouling develops.

The student for this project must have a strong background in marine ecology, marine invertebrate biology, and molecular methods of studying microbial species assemblages.

References

[1]. Watson, M.G., A.J. Scardino, L. Zalizniak, and J. Shimeta, 2016. Inhibition of invertebrate larval settlement by biofilm ciliates. Marine Ecology Progress Series 557:77-90.

[2]. Shimeta, J., J. Cutajar, M.G. Watson, and T. Vlamis, 2012. Influences of biofilm-associated ciliates on the settlement of marine invertebrate larvae. Marine Ecology Progress Series 449:1-12.

Contact Details

To discuss this project further please contact: Associate Professor Jeff Shimeta ([email protected]) 1st Supervisor Dr. Nathan Bott ([email protected]) 2nd Supervisor



Roles of Benthic Invertebrates in the Sequestration and Mobilisation of Heavy Metal Contaminants in the Gippsland Lakes

Biosciences and Food Technology Discipline/Centre for Environmental Sustainability & Remediation – RMIT Bundoora West

Project Description

Like many coastal marine and inland water bodies, the Gippsland Lakes in eastern Victoria receive pollutants from a wide range of anthropogenic sources. Heavy metals such as mercury have been measured at high levels in sediments and biota of the Gippsland Lakes, but there is a poor understanding of the ecological processes affecting their toxicity, accumulation in the food web, sequestration in the environment, and mobilisation or release from sediments to the water column and biota. Under continued pressure from anthropogenic disturbances, land management practices and the emerging threats from climate change, alterations to environmental conditions could greatly affect the storage, release, and movements of heavy metals through the ecosystem.

This project will investigate the role of aquatic benthic invertebrates (e.g. worms, crustaceans, molluscs) in the movements of heavy metals within the Gippsland Lakes. Field and laboratory studies will determine how the abundance and activities of these animals influence the dynamics of metals; and experiments will determine how environmental stresses such as changes in temperature, oxygen, salinity, nutrients, and pH affect these processes. The results will help to guide management decisions in state agencies that are responsible for the Gippsland Lakes ecosystem.

The student for this project must have a strong background in aquatic biology and ecology, particularly of benthic invertebrates, as well as good field and laboratory skills. The student will work as part of a multi-university research team investigating the Gippsland Lakes in conjunction with state agencies (East Gippsland Catchment Management Authority; Victorian Department of Environment, Land, Water & Planning). The student will develop expertise at the interface of environmental science and management, and will build valuable professional contacts and relationships in these areas.

References

[1]. Harris, G. et al. 1998. Gippsland Lakes Environmental Audit: Review of Water Quality and Status of the Aquatic Ecosystems of the Gippsland Lakes. Gippsland Coastal Board, Bairnsdale.

[2]. GLMAC, 2013. Gippsland Lakes Environmental Strategy. Gippsland Lakes Ministerial Advisory Committee, Bairnsdale.

Contact Details

To discuss this project further please contact: Associate Professor Jeff Shimeta ([email protected]) 1st Supervisor



Improving management of Southern Bluefin tuna health

Biosciences and Food Technology Discipline/Marine Biosecurity and Biodiversity, Centre for Environmental Sustainability and Remediation – RMIT Bundoora West

Project Description

Southern Bluefin tuna (SBT) is a high-value aquaculture sector with a high price placed on individual fish. Health impacts from parasites and management of those impacts, can have an effect on industry productivity and profitability [1]. There are a number of key parasites of concern to the SBT industry. Blood flukes have historically been an on-going management issue for the SBT industry [2], and primarily identified as the cause of the mortality. The causative agent of swimmer syndrome also causes sporadic cases of mortality and has previously been associated with changes in environmental conditions resulting in mortalities [3]. With the introduction of praziquantel for the treatment of blood fluke in SBT [4], mortalities due to infections have significantly decreased. The project will investigate if this change is consistent over time (year and time in ranching) and determine the on-going implications for the industry. Improved knowledge of the biology of blood flukes and the effect of praziquantel on them would help to modify or design new management strategies and assess risks. This project will determine effect of distance from cages not treated with praziquantel on parasite load and performance of tuna in other cages at the same site based on the infections of SBT in treated and untreated cages and survival time of free living blood fluke stages in sea water. The effects of moving offshore farmed SBT to the Port Lincoln farming zone for harvest (for up to 9 weeks) and the effect on blood fluke infection will also be assessed. The project will also monitor the presence of swimmer syndrome cases if/when they develop to better understand industry prevalence and attempt to relate that to environmental factors. The project will primarily be utilizing harvest samples which will be sent to market there are no ethical concerns. If dedicated SBT samples are required then appropriate approvals will be sought prior to undertaking this work. References

[1]. Nowak et al. EAFP 26 (2006) 38-42 Review [2]. Garza et al. Aquaculture 469 (2017) 44-49 [3]. Hayward et al. Veterinary Parasitology 173 (2010) 107-115 [4]. Hardy-Smith et al. Aquaculture 334 (2012) 39-44 Contact Details

To discuss this project further please contact: 1st Supervisor – Dr Nathan Bott ([email protected]) 2nd Supervisor – Prof. Barbara Nowak ([email protected])



Molecular approaches to understanding Victorian zooplankton communities

Biosciences and Food Technology/Discipline/Marine Biosecurity and Biodiversity, Centre for

Environmental Sustainability and Remediation – RMIT Bundoora West Project Description

This project will seek to understand the dynamics of Victorian zooplankton communities through the use of environmental DNA (eDNA)-based molecular approaches. There is an increasing use of eDNA approaches to study planktonic communities as a larger number of samples can be analysed, it can identify more species than traditional methods, and these methods are particularly effective in studying the spread of Marine Invasive Species (MIS) [1]. The aim of this project is to utilise metabarcoding [2] high throughput sequencing to understand the seasonal dynamics of zooplankton in Victoria marine environments. The project will be initially focused on the Gippsland Lakes in Eastern Victoria but will extend to study sites within Port Phillip Bay and Bass Strait. The project will sample plankton communities along a gradient of anthropogenic influence and explore key differences in the overall community structure, seasonality, presence of MIS and provide important information about the biodiversity of an ecological important marine community. It has been suggested that south eastern Australia is a ‘hotspot’ for oceanographic change due to changing sea surface temperatures [3] and it is well established that some MIS have long planktonic stages and can use this life-stage to expand their range following introduction to non-endemic areas through human introductions [4]. This project will provide important and lacking information on these communities, and will provide a baseline for future research on environmental change due to changing sea surface temperatures and increased anthropogenic influence. Understanding zooplankton communities will have direct links to the understanding of important commercial fisheries as changes in zooplankton communities will influence fish populations. Our molecular approach if coupled with hydrodynamic modelling will provide a predictive tool for MIS range expansion. The HDR student involved in this project would need training on correct and safe fieldwork procedures, use of high-throughput sequencing platforms, and bioinformatic analyses. This can all be provided by existing personnel from the School of Science. References

[1].Bott et al. Biotechnology Advances 28 (2010) 706-714 (Review) [2].Pochon et al. Biofouling 31 (2013) 241-251 [3].Kelly et al. Estuarine, Coastal and Shelf Science 180 (2016) 242-257 [4].Richardson et al. Molecular Ecology 25 (2016) 5001-5014

Contact Details

To discuss this project further please contact: Dr Nathan Bott ([email protected]) 1st Supervisor Assoc. Prof. Jeff Shimeta ([email protected]) 2nd Supervisor

mailto:[email protected])



Development and characterization of honey-based products for treating atherosclerosis

Biosciences and Food Technology Discipline – RMIT Bundoora West

Project Description

Oxidative stress and hypercholesterolemia are interrelated factors and implicated in the pathogenesis of acute and chronic disorders such as cardiovascular (CDV) atherosclerosis. Oxidative stress results from excessive production of reactive species (ROS and RNS). Cholesterol is an indispensable compound in animal and human cells. An abnormality in either cholesterol metabolism or transport through the plasma is involved in cholesterol accumulation. A significant increase in lipoperoxidation products and/or a decrease in some plasma antioxidants may advance hypercholesterolemia. Cholesterol is highly associated with atherogenesis. It is postulated that in vivo oxidation of low density lipoprotein cholesterol (LDL-C) triggers atherosclerosis. In addition, high LDL-C level forms plaques in blood vessels. If they occur in coronary arteries, they may cause blockage and heart attacks. Many approaches have been used to reduce oxidative stress and hypercholesterolemia. These include gene therapy, synthetic drugs, caloric restriction, antioxidants, vitamins, etc. However, the use of most of these is limited due to contradictory conclusions, ethical issues and practical hurdles. Plants are an abundant reservoir of powerful antioxidant polyphenols and cholesterol lowering compounds. Hence, the development of natural products with the capacity to boost anti-oxidative protection and strengthen the endogenous defense has attracted attention. Honey is a promising candidate because clinical studies provide overwhelming evidence of its therapeutic properties from different botanical and geographical origin. These include antimicrobial, antioxidant, anti-inflammation, wound healing, anti-cancer, anti-atherosclerosis, etc. Nectar and pollen forage by honey bee promotes the transition of medicinal substances from plants into honey, thus honey can be a carrier of phenolic phytochemicals. Given the above, this project will develop four honey samples utilising selected medicinal plant species. These plant species possess huge benefits over oxidative stress and hypercholesterol, and they are expected to be good sources of phytochemicals for the production of novel nutraceutical honeys targeting specific health benefits. Honey phytochemicals with medicinal properties will be identified and concentrated up from the original source thus functioning as bioactive compounds within the dynamic range of therapeutic activity. These will be introduced in delivery vehicles for oral ingestion made of gelatin, as the continuous matrix, chitosan to ensure thermal stability of the hydrogel, and honey to provide binding properties and bulk in the soft gel. Analytical, physicochemical, textural and sensory properties of the novel delivery system will be characterized for eventual scaling up and commercialization.

References

[1]. Cherubini A., et al., Current Pharmaceutical Design, 2005. 11: 2017-2032. [2]. Ajibola A., J.P. Chamunorwa, K.H. Erlwanger, Nutrition & metabolism, 2012. 9: 61-67. [3]. Alvarez-Suarez J.M., F. Giampieri, M. Battino, Current Med Chem, 2013. 20: 621-638. [4]. Alvarez-Suarez J.M., et al., Foods, 2014. 3: 420-432. Contact Details

To discuss this project further please contact: Dr Nitin Mantri ([email protected]) Joint Supervisor – Office: 9925 7152 Professor Stefan Kasapis ([email protected]) Joint Supervisor – Office: 9925 5244 Professor Eddie Pang ([email protected]) Associate Supervisor – Office: 9925 7137






Identification and validation of candidates for stress tolerance in chickpea

Biosciences and Food Technology Discipline/ Pangenomics Group - RMIT Bundoora West

Project Description

Chickpea (Cicer arietinum) is the second most important pulse crop globally. Chickpea productivity is largely affected due to a number of biotic and abiotic stresses. Recently, Dr Mantri’s lab has comprehensively analysed chickpea transcriptome in response to salt and drought stress. This includes identification of mRNAs, miRNAs, lncRNAs, and DNA methylation patterns associated with drought and salt tolerance and sensitivity. Several novel gene loci and alternatively spliced (AS) isoforms were also identified. In this project, these candidates will be validated through protein modelling and CRISPR/Cas9 system. Comparative modelling will be used to predict the protein structure of selected candidates. Comparative modelling predicts the 3-D structure of a given protein sequence (target) based primarily on its alignment to one or more proteins of known structure (templates)[1]. We will use MODELLER program and ModBase database to calculate comparative modelling. The prediction process consists of fold assignment, target-template alignment, model building, and model evaluation. As a precursor to the prediction process, we will perform the following steps:

(i) Sequence conversion to PIR file format which is readable by MODELLER, (ii) Search for suitable template structures, and (iii) Select a template.

Upon in silico validation and protein modelling, selected candidates will be validated using CRISPR/Cas9 system. Since the initial development of a programmable CRISPR/Cas 9 system, it has been rapidly applied to achieve efficient genome editing in human cell lines, zebrafish, maize, rice, Arabidopsis and so on [2]. The small size of guide RNA allows the co-delivery of multiple single guide RNAs with Cas9 on the cell making it feasible to simultaneously edit more than one target sequences at the same time. The ease and robustness of this system makes it an attractive genome editing tool for plant biology. CRSIPR/Cas 9 system has been successfully applied in model plants like Nicotiana benthamiana, N. Tabaccum and Arabidopsis, and crops such as wheat, maize, rice, sorghum, and tomato [3]. However, there are no reports for using CRISPR /Cas9 to knockout coding or non-coding regions of chickpea. References

[1]. Webb B, Sali A. Curr Protoc Bioinformatics, 54, pp. 5.6.1-5.6.37, 2016. [2]. Nejat N, Rookes J, Mantri N, Cahill D (2016) Critical Reviews in Biotechnology, DOI: 10.3109/07388551.2015.1134437 [3]. Nejat N, Mantri N (2017) Current Issues in Molecular Biology 23, 1

Contact Details

To discuss this project further please contact: Dr Nitin Mantri ([email protected]) Joint Supervisor – Office: 9925 7152 Dr Paul Ramsland ([email protected]) Joint Supervisor – Office 9925 7024





Management of plant pathogens using next generation nano-sensors

Biosciences and Food Technology Discipline / Pangenomics Group/ NanoBiotechnology Research Laboratory and Ian Potter NanoBioSensing Facility – RMIT City/Bundoora West

Project Description

Plant pathogens are a major limiting factor for sustainable vegetable production. Early detection of plant pathogens in nurseries and fields is crucial to effectively manage their spread or design strategy to eradicate them. Several molecular methods are currently used of detection of these plant pathogens. Although some of these methods show outstanding specificity and sensitivity, the major limitations of molecular methods are the requirement of specialised equipment, trained personnel, and laborious nature of the test that makes them non-feasible for in-field testing by farmers.[1,2] In this project, the PhD student will be involved in developing a new specific, sensitive, easy to use, and portable detection platform based on Surface Enhanced Raman Spectroscopy (SERS). For this, the PhD scholar will be involved in (i) glass house assays for pathogen infections, (ii) bioinformatics analysis to design molecular probes, (iii) developing new chemical synthesis strategies to fabricate nanomaterials with a control over their size and shape, (iv) functionalising the nanoparticles with recognition probes developed based on bioinformatics, (v) developing SERS substrates and (vi) optimising sensor performance for detection of pathogens in plants. On a need basis, the PhD scholar will be jointly based at RMIT Bundoora and City campuses to work across Pangenomics Group and the Ian Potter NanoBioSensing Facility in a highly cross-disciplinary environment. The project will involve a number of collaborations including University of Manchester, UK. The PhD scholar will use specialised techniques including microscopy (SEM, TEM, HRTEM); spectroscopy (absorbance, fluorescence, FTIR, EDX, XPS); crystallography (XRD); statistical analysis (cluster tools, discriminant tools, regression analysis) and Raman spectroscopy. Overall, this project will provide a highly cross-disciplinary training across materials science, nanotechnology, chemistry, plant pathology and microbiology, leading to several high quality publications. References

1. Boonham N, Kreuze J, Winter S, et al., (2014) Virus Research, 186:20–31. 2. Kashyap PL, Rai P, Sharma S, et al., (2016) Sustainable Agriculture Reviews 21, DOI 10.1007/978-3-319-39306-3_8

Contact Details

To discuss this project further please contact: Dr Nitin Mantri ([email protected]) Joint Supervisor – Office: 9925 7152 Dr Rajesh Ramanathan ([email protected]) Joint Supervisor – Office 9925 2887





Mapping the structural and antigenic features of viral envelope glycoprotein assemblies

Biosciences & Food Technology Discipline – RMIT Bundoora West

Project Description

Many enveloped viruses that cause disease in animals and humans rely on a glycoprotein molecular assembly to specifically bind and initiate entry of virus into the host cell. For example, in HIV-1 the viral envelope protein (Env) is produced as gp160 that is cleaved to form the gp120-gp41 trimeric assembly that is involved in binding to its target chemokine receptors, CCR5 and CXCR4, on host cells [1,2]. Many enveloped viruses causing significant human diseases also use glycoprotein complexes to recognize and gain entry into host cells including influenza A, Hepatitis viruses, Dengue, Zika, Ebola and Lassa. A general feature of these viral host recognition glycoproteins is their high level of sequence and structural diversity. High levels of sequence and structural diversity is likely driven by efforts of the viruses to maintain function while evading selective pressures from the host immune system. This project will employ structural bioinformatics approaches to study the potential influence of sequence polymorphisms on the three-dimensional structure of viral envelope glycoprotein assemblies [3,4]. Predictions of immune selection will also be used to examine the spatial relationship between all possible antigenic regions of viral glycoprotein complexes, which may guide future vaccine design efforts. Additionally, a series of biophysical measurements (e.g. dynamic light scattering, differential scanning calorimetry and circular dichroism) and high resolution imaging techniques (e.g. atomic force microscopy, electron microscopy and crystallography) will be performed on selected candidates to assess structure, stability and function of viral glycoproteins in the context of artificial viral membranes or as structured nanoparticles. Through collaboration the project will also assess candidates as possible viral vaccine delivery systems or as platforms for development of new antivirals. References

[1]. Gorry PR et al. J Leukoc Biol (2014) 95:71. [2]. Ward AB, Wilson IA. Immunol Rev (2017) 275:21. [3]. Cashin K et al. PLoS One (2014) 14:e109771. [4]. Sterjovski et al. Virology (2010) 404:269. Contact Details

To discuss this project further please contact: Dr Paul Ramsland ([email protected]) Senior Supervisor (Bundoora) Professor Paul Gorry Associate Supervisor (Bundoora) Dr Aaron Elbourne Associate Supervisor (City)



Harnessing carbohydrate-based informatics (glycoinformatics) to develop biosensors for surveillance of cancer and infection

Biosciences & Food Technology Discipline – RMIT Bundoora West & City Campuses

Project Description The surfaces of microbial pathogens and cancer cells are decorated by a wide variety of carbohydrates (glycans) that are attached to membrane-associated glycoproteins and glycolipids [1]. While some carbohydrate determinants or epitopes are potentially highly specific to a particular cell type, normally a target cell can be distinguished by a diverse and sometimes dynamic glycan surface profile. Carbohydrate-binding proteins such as lectins and antibodies bind complex glycan epitopes or interact with specific building blocks (monosaccharides) with or without restrictions on the building blocks participating in particular linkages (position and stereochemistry of glycosidic linkages). Consequently, through combining information from multiple carbohydrate-binding proteins it is readily possible to distinguish pathogens from host and cancer cells from healthy tissues. While empirical testing can establish selectivity it is not always obvious what lectins or carbohydrate-binding antibodies will achieve, specificity and sensitivity required for diagnostic applications. However, there is a large body of publically available glycan specificity, structure-function data [2], and genomic data relevant to human disease, much of which has not been used for prospective development of glycan-based diagnostics and therapeutics. This project will employ bioinformatics and data mining approaches to identify carbohydrate-binding proteins suitable disease and biomarker discrimination. Initial validation of predicted glycan targeting arrays will involve immunoassays and biophysical interaction analyses with model recombinant glycoproteins and high resolution imaging of human cell lines (confocal and super-resolution microscopy, and atomic force microscopy). The selected sets of carbohydrate-binding proteins will be functionalized on integrated optical biosensors [3] and smart sensor material surfaces. The ability to rapidly measure carbohydrate profiles from small quantities of biological fluids and cells will find applications in a wide range of human and animal diseases. References [1]. Soliman C, Yuriev E, Ramsland PA. Curr Opin Struct Biol (2017) 44:1 [2]. Yuriev E, Ramsland PA. Front Immunol (2015) 6:300 [3]. Szydzik C et al. Lab Chip (2017) doi:10.1039/c7lc00524e

Contact Details To discuss this project further please contact: Dr Paul Ramsland ([email protected]) Senior Supervisor (Bundoora) Dr Jeffrey Chan Associate Supervisor (City) Distinguished Professor Arnan Mitchell Associate Supervisor (City)



Nanochip biosensor for assessment of endothelial cell damage in diabetes

Bioscience and Food Technolgy/Sir Ian Potter NanoBioSensing Facility – RMIT City

Project Description

Diabetes, an incurable syndrome, may lead to development of new blood vessels on retina leading to impaired vision conditions called diabetic retinopathy (DR). The impact of diabetes on morbidity, mortality and health care costs is significant. From an ophthalmic perspective, this is of particular importance as diabetes is the commonest cause of vision loss in working age adults in the developed world. Approximately one third of adults with diabetes have retinopathy and the number of people affected is expected to triple by 2050. Further vision loss and blindness is usually preventable if DR is detected and treated early. This project therefore, will employ a multidisciplinary nanobiotechnology-based approach for early prediction of the onset and progression of DR.

This study highly leverages on existent data generated by us and NHMRC-CTC collaborators (see our references). The PhD student will be engaged in developing knowledge building this highly interdisciplinary project for next 3 years in the newly funded Sir Ian Potter NanoBiosensing Laboratory (RMIT University) and NHMRC-Clinical trials Centre (University of Sydney). The student will have opportunity to work closely with the research team and will continue to contribute towards a milestone-based delivery of the project to ensure timely completion and successful delivery of the clearly defined and achievable project aims.

A prospective PhD student with strong background knowledge of Analytical Chemistry and/or Biology with some credible experience in nanomaterial characterisations and nucleic acid bio- conjugations techniques are encouraged to apply. Student will have ample opportunities to learn state-of-the-art cross disciplinary tools and techniques available in RMIT and NHMRC Clinical Trails Centre (CTC) through collaboration. In addition student will be nurtured for research ethics, critical thinking, time & project management, and problem-solving skills.

References [1]. Ranjan, A.K., Kumar, U., Hardikar, A.A., Poddar, P., Nair, P.D., and Hardikar, A.A. (2009). Human blood vessel-derived endothelial progenitors for endothelialization of small diameter vascular prosthesis. PLoS One 4, e7718 [2]. Sharma, T.K., Ramanathan, R., Weerathunge, P., Mohammadtaheri, M., Daima, H.K., Shukla, R., and Bansal, V. (2014). Aptamer-mediated 'turn-off/turn-on' nanozyme activity of gold nanoparticles for kanamycin detection. Chemical Communications (Camb) 50, 15856-15859. [3]. Weerathunge, P., Ramanathan, R., Shukla, R., Sharma, T.K., and Bansal, V. (2014). Aptamer-controlled reversible inhibition of gold nanozyme activity for pesticide sensing. Analytical Chemistry 86, 11937-11941. [4]. Farr, R.J., Januszewski, A.S., Joglekar, M.V., Liang, H., McAulley, A.K., Hewitt, A.W., Thomas, H.E., Loudovaris, T., Kay, T.W., Jenkins, A., et al. (2015). A comparative analysis of high-throughput platforms for validation of a circulating microRNA signature in diabetic retinopathy. Scientific Reports 5, 10375.

Contact Details

To discuss this project further please contact: Dr Ravi Shukla Email: [email protected]; Phone: +61 3 9925 2970



Metal Organic Framework based non-viral vectors for targeted knockdown of telomerase gene in prostate cancer

Bioscience and Food Technology/NanoBiotechnology Research Laboratory – RMIT Bundoora/City

Project Description

Prostate cancer (PC), according to the Australian Institute of Health and Welfare, is the second leading cause of cancer death in males and is estimated to afflict 1 in 5 men. Metal-organic frameworks (MOFs), a new class of hybrid materials, have emerged as promising platforms for cellular delivery and have been used for efficient delivery of nucleotides and protein[1]. This project will involve the synthesis and characterization of suitable biocompatible MOFs. These will be used as non-viral vectors to encapsulate and deliver nucleic acids (NAs) which will target the aberrant expression of the human telomerase gene in PC cells. Telomerase expression has been reported to be active and over expressed in 47% to 100% of PC cases, and disrupting its expression can provide valuable therapeutic results[2]. The first aim of the project will be synthesis of three different kinds of MOFs that have been reported to be biocompatible. These will include (A). MOFs based on zirconium ions, termed Universitet i Oslo (UiO) series which have successfully been used to deliver siRNAs and cisplatin to ovarian cancer cells for enhanced anticancer efficacy [3]. (B) MOFs based on porous iron (III) carboxylates of the Materials of Institute Lavoisier (MIL) series which can efficiently encapsulate and release biologically relevant cargoes with minimal in vivo toxicity. The iron- based cores also possess good relaxivities, which enable them to act as contrast agents for magnetic resonance imaging in vivo [4]. (C) MOFs based on Zeoliticimidazolate frameworks (ZIFs) which are ideal as drug delivery nanocarriers due to their ultrahigh surface areas, abundant functionalities, and exceptional thermal and chemical stabilities. They are stable in neutral and alkaline conditions but degrade rapidly in acidic environment and have also been implicated as theranostic agents for simultaneous diagnostic and therapeutic applications[5]. The second aim will focus on the encapsulation of NAs inside the MOFs which will target the human telomerase gene. These targeting NAs will be of two types: (A) siRNAs and (B) CRISPR/Cas9 plasmid vectors. Following successful encapsulation, the MOF@NA conjugates will be transfected into mammalian prostate cancer cell line PC3 which will lead to knockdown of telomerase expression.

Synthesis of the MOFs and MOF@NA conjugates will be done following the solvothermal process of MOF synthesis and biomimetic mineralisation. The particles will be characterized for their size, shape, porosity, surface characteristics like surface charge, hydrodynamic radius and nucleic acid encapsulation. Transfection assays will be carried out to assess delivery efficacy of the MOF@NA conjugates into PC3 cells. Down regulation of expression will be checked by quantitative polymerase chain reaction (qPCR) and Western Blot analysis.

References

[1].McKinlay, A.C., et al., Angew Chem Int Ed Engl, 2010. 49(36): p. 6260-6. [2].Meeker, A.K., Urologic Oncology: Seminars and Original Investigations, 2006. 24(2): p.

122-130. [3].He, C., et al., J Am Chem Soc, 2014. 136(14): p. 5181-4. [4].Horcajada, P., et al., Nat Mater, 2010. 9(2): p. 172-178. [5].Sun, C.Y., et al., Dalton Trans, 2012. 41(23): p. 6906-9.

Contact Details

To discuss this project further please contact: Dr Ravi Shukla Email [email protected]



Investigation on the plant dynamics and fungal variability between remnant, translocated and reintroduced populations of Caladenia

amoena (Orchidaceae)

BioSciences and Food Technology Discipline/Plant Interactions and Pathology Lab RMIT Bundoora West

Project Description:

Conservation efforts on critically endangered orchids were mandated according to government legislation under the EPBC Act (Commonwealth of Australia 2017). This included Caladenia amoena, the charming spider orchid only found in 1 population in Victoria. Two action plans were conducted since 2008, with a sub population translocated to a more secure site nearby and a reintroduced population resulting from in vitro germination. This project will investigate the plant dynamics of the 3 sites and isolate fungi to determine if either interventions were effective to conserve the remnant orchid population. Results will be used for future land management strategies to improve conservation efforts. The project will involve field work to compare plant growth and molecular biology for sequencing of fungal isolates based on previous studies from our research group including investigation of seasons for fuel reduction burns (Jasinge 2014) and phenological influences on mycorrhizal competitiveness (Huynh et al., 2009). No specific or specialist training required. Permits to Conduct Research on public land and to Take Protect Flora have been applied for 2018 collections. References:

[1]. Commonwealth of Australia (2017a). Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act). Revised 2017 (accessed 100917). http://www.environment.gov.au/epbc.

[2]. Commonwealth of Australia 2017b). Caladenia amoena –Charming spider orchid. Revised 2017 (accessed 100917) http://www.environment.gov.au/cgi-bin/sprat/public/publicspecies.pl?taxon_id=64502.

[3]. Huynh T, Thompson R, McLean CB and Lawrie AC. (2009). Functional and genetic diversity of mycorrhizal fungi from single plants of Caladenia formosa G.W. Carr (Orchidaceae). Annals of Botany 104:757-765.

[4]. Jasinge N (2014). The effect of seasonal burning on three Australian native orchids, Masters by Research, Applied Science, RMIT University. Contact Details:

To discuss this project further please contact: 1st Supervisor – Dr Tien Huynh on 03 9925 7124 or email [email protected] 2nd Supervisor – Prof. Ann Lawrie

http://www.environment.gov.au/epbc

http://www.environment.gov.au/cgi-bin/sprat/public/publicspecies.pl?taxon_id=64502




Virulence and colonization of Campylobacter concisus in the gastrointestinal tract environment in relation to other gut microbes

Biosciences & Food Technology Discipline/ Pathogens & Therapies Research Group – RMIT

Bundoora Project Description

Campylobacter concisus, is a bacterium of the human oral flora, and is known to be involved in gastroenteritis in children and other individuals with lowered immune responses [1]. More importantly this bacterium was reported to play a pathogenic role in inflammatory bowel diseases (IBD). However, the pathogenic role and virulence of this bacterium in those patients has not been fully understood. Our previous research data and recent findings in the field highlighted the importance of investigating the virulence factors in bacterial strains isolated from the oral cavity and several sections of the gastrointestinal tract of patients and healthy individuals [2, 3]. Yet, it is not known if the same bacterial strains from the oral cavity can be responsible for producing the disease or symptoms in the gastrointestinal tract. This project will investigate the potential virulence characteristics of C. concisus oral and intestinal strains isolated from patients and healthy individuals using molecular microbiology techniques, including genome sequencing data and mutated C. concisus strains which have been generated in previous studies by our research team [4]. Virulence factors such as biofilm formation, motility and toxin production will be investigated. Bacterial colonisation and pathogenic outcomes of gastrointestinal infections can occur in the context of a disrupted gut microbiota. Therefore, we will investigate the composition of the gut microbiota of patients presenting with C. concise infections and IBD to determine if there are underlying disruptions that that are specifically correlated with C. concisus infection. Therapeutic approaches to modifying or repairing the microbiota may have a role in disease avoidance or recovery.

Potential candidates for this project are expected to have experience in molecular techniques and in prokaryotic and eukaryotic cell culture techniques and are willing to work with and handle laboratory animals.

The research involves experiments in laboratory animals and may also include collecting data from patients. Hence, Animal ethics and Human ethics approvals are needed. To include any specific or specialist training required.

References

[1]. Istivan, T. et al., J. Med. Microbiol, 53 (2004), 483-493. [2]. Kaakoush, N. et al. PLoS One, 6 (2011) e29045. [3]. Istivan & Coloe. Microbiology, 152, (2006) 1263-1274. (a review) [4]. Huq, M. et al., Gene Reports, 6, (2017) 8-14.

Contact Details

To discuss this project further please contact: First Supervisor – Dr. Taghrid Istivan ([email protected]) Second Supervisor – Prof. Rob Moore ([email protected]





Cellular mechanisms of bioactive compound release to develop effective drug delivery systems

Biosciences & Food Technology Discipline/Pathogens & Therapies Research Group RMIT –

Bundoora West

Project Description

Therapeutic molecules including peptides, nanoparticles and small proteins have been thoroughly investigated and developed as anticancer, antimicrobial or immunomodulatory treatments. Our previous research on therapeutics peptides has identified small molecular weight peptides with significant cytotoxic effects on cancer cells making them an attractive therapeutic model [1]. Some of these peptides also possess antimicrobial effect against pathogenic antibiotic resistance bacteria [2]. However the in vivo stability of these peptides and the targeted delivery to the infected site are to be investigated [3]. This study aims to develop a delivery model for therapeutic particles in eukaryotic and prokaryotic cells by applying a novel responsive on-off bioactive compound release biopolymer system to protect, deliver and timely release of the small therapeutic molecules in a targeted drug delivery approach [4]. Another focus of this study is the effective use and delivery of probiotics such as lactic acid bacteria (LAB) and Bifidobacteria to ensure their viability and therapeutic value. Probiotics have been proved to possess an immunomodulatory effect in the gastrointestinal tract and other body systems in addition to their role in modifying the gut microbiota and the prevention and treatment of inflammatory bowel diseases [5]. Therefore, it is of great importance to investigate novel controlled release delivery systems to protect the probiotics from the effect of the gastrointestinal tract environment and antibiotics to ensure their abundance and viability in the treatment site. Delivery vehicles of therapeutic substances will be formulated via a variety of protocols for easy adaptation by industry, scaling up and eventual commercialisation. For example, microencapsulation or emulsification will be utilised to produce smooth microspheres that pack the probiotic bacteria payload for efficient oral delivery. Microspheres will be composed of one or more biologically compatible and non-toxic biopolymers derived from natural sources. The structure and stability of these microspheres will be further enhanced by crosslinking with natural, non-toxic and colorless crosslinkers like the microbial transglutaminase. These will survive during exposure to the adverse environment of the upper segments of the GI tract hence releasing the bacterial payload in the distal part of the small intestine. Potential candidates for this project are expected to have knowledge and experience in pharmacology/biochemistry, and in both prokaryotic and eukaryotic cell culture techniques and are willing to work with and handle laboratory animals. Animal ethics approval is needed to carry on the animal experiments in the final part of the project.

References

[1]. Istivan T., et al. Plos One 6 (9) (2011). https://doi.org/10.1371/journal.pone.0024809. [2]. Hu, J. Istivan, T. and Pirogova E, Medical Data: Medical Review, 6 (1) (2014), 11-16. [3]. Pirogova, E. Istivan, T. et al. Current Pharmaceutical Biotechnology, 12 (2011) 1117-1127. [4]. Paramita, V.D., Bannikova, A. & Kasapis, S. (2016). Food Hydrocolloids, 53, 284-292. [5] F. L. Yan Fong et al. International Reviews of Immunology, 35 (2016), 179–188.

Contact Detail

To discuss this project further please contact: First Supervisor – Dr. Taghrid Istivan ([email protected]) Second Supervisor – Prof. Stefan Kasapis ([email protected])



DR232 – PhD (Food Science) MR232 – Master of Science (Food Science)


Understanding the Molecular Origin of Interactions between Dairy Proteins and Phenolic Compounds

Bioscience and Food Technology Discipline / Applied Chemistry & Environmental Science Discpline –

RMIT Bundoora West & City

Project Description

Dairy proteins are the main ingredients in liquid food formulations providing techno- and biofunctionality. The food industry aims to further enhance the nutritional quality of these products by incorporating sufficient amounts of insoluble dietary fibre (IDF) in formulations. For technological reasons, we have been unable to do so, with problems ranging from the development of off flavours, upon thermal treatment and subsequent storage, to sedimentation issues following IDF addition to the complex matrices of beverages. We hypothesize that phenolic acids, which are endogenous components of IDF, are affected by industrial processing leading to an overall reduction in product quality. This is manifested by the appearance of rancidity during ambient storage and subsequent consumption. Processing difficulties are compounded by the lack of fundamental understanding on the interactions between bioactive components of the insoluble dietary fibre and co-solute, notably proteins whose polyelectrolyte behaviour is altered considerably within the pH of interest (~7.0 to 4.0) during liquid manufacture. The main aim of this project, therefore, is to understand, manipulate and control the molecular interactions of insoluble dietary fibre with other ingredients (particularly dairy proteins) in liquid food systems in order to formulate products with superior technofunctionality and improved health benefits. Micro-constituents of dietary fibre, including phenolic compounds, are known to possess potent antioxidant activity, which contributes to the inhibition of coronary heart disease, stroke and some cancers. Thermal processing and subsequent storage at ambient temperature might, however, convert these phenolics into malodorous chemicals that adversely affect the organoleptic characteristics of the beverages. These are severe limitations currently restricting enrichment of beverages with cereal fibres that are important for health and prevention of disease. To overcome the drawbacks of current technology, a fundamental understanding of chemical modifications in micro-constituents of insoluble fibre alongside with their interactions with major ingredients in formulations, i.e. dairy proteins, is required. To gain this understanding, research will focus on conditions of modern manufacturing that include ultrahigh temperature processing (UHT) and the consumer expectation for prolonged storage, typically twelve months, without refrigeration.

References

[1]. Alqahtani, N.K., Ashton, J., Katopo, L., Haque, E., Jones, O.A.H. & Kasapis, S. (2014). Bioactive Carbohydrates and Dietary Fibre, 4, 84-92

[2]. Dokuhaki, M., Hung, A., Day, L. & Gras, S.L. (2017). Journal of Structural Biology, 198, 82-91 [3]. Kasapis, S. (2008). Critical Reviews in Food Science and Nutrition, 48, 341-359 (Review) [4]. Ray, N. B., Luu, V. T., Liang, J., Hung, A. & Karagiannis, T. (2015). Hellenic Journal of

Nuclear Medicine, 18, 51-62 Contact Details

To discuss this project further please contact: Professor Stefan Kasapis ([email protected]) 1st Supervisor – Office 201.06.09 Dr Andrew Hung ([email protected]) 2nd Supervisor – Office 003.02.24





Stimuli responsive on-off switching in bioactive compound release from high-solid biopolymer systems

Bioscience and Food Technology Discipline/Microbiology Group – RMIT Bundoora West

Project Description

The rate of bioactive compound diffusion, including vitamins, essential fatty acids and pharmacotherapeutics in glassy biomaterials is of considerable interest in the food and nutraceutical manufacture, and several theoretical models have been employed in relation to a predictive approach. Literature shows that the structure of biopolymer matrices (mainly protein or polysaccharide) is critical in the diffusion of bioactive components. Therefore, the first step in this PhD project would be to characterise the thermomechanical behaviour of polymeric matrices in relation to their glass transition temperature (Tg). Among the predictive models of structural relaxation, the free volume theory of diffusion is considered to treat transport phenomena within glassy polymers with some success. The theory hypothesizes that at temperatures above the glass transition temperature, the effective diffusion coefficient of microconstituent transport would increase in accordance with the free volume of the polymer matrix. Within the glass transition region, amorphous viscoelastic materials see a dramatic reduction in free volume with rapid cooling, which can be monitored as a broad variation in heat capacity or viscosity. The dramatic increase in viscosity is accompanied by structural reorganisation leading to limited translational mobility that promotes physicochemical stability. Devitrification can be achieved by increasing the temperature above Tg, with the frozen-in molecules starting to resonate leading to a structural relaxation of the condensed matrix.

Experimental observations of structural relaxation within the glass transition region in this PhD research will be followed in a number of systems of natural polymers with the free volume theory in the way quantified by the Williams-Landel-Ferry (WLF) equation. The aforementioned work will be carried out in model systems of a single biopolymer with small-molecule co-solute at high levels of solids leading to the development of theoretical expressions between free volume theory and molecular interactions. These will be preparations of stationery boundaries but hydrogellable materials employed in sustained release of bioactivity are water swellable in response to the changing physicochemical environment of the human gastrointestinal tract and these will be analysed, as well. Naturally occurring proteins or polysaccharides are nutritionally advantageous over the laboratory synthesized counterparts and offer avenues of sustained/targeted release in response to changing acidity or saline environment. Their desirable and extensive swelling index for formulation design is accompanied by biocompatibility and biodegradability due to the ability to hold extremely high levels of water unlike their synthetic analogues. The aim of this PhD project, therefore, is to understand the diffusion mechanism controlling bioactive compound release from natural formulations of industrial interest in stationary and swellable boundaries that simulate gastrointestinal fluids.

References [1]. Paramita, V.D., Bannikova, A. & Kasapis, S. (2016). Food Hydrocolloids, 53, 284-292 [2]. Kasapis, S. (2008). Critical Reviews in Food Science and Nutrition, 48, 185-203 (Review) [3]. Istivan, T., Pirogova, E, Gan, E., Almansour, N., Coloe, P. & Cosic, I. (2011). PLoS, 6, 1-10 [4].Pirogova, E. Istivan, T., Gan, E. & Cosic, I. (2011). Current Pharmaceutical Biotechnology, 12, 1117-1127

Contact Details

To discuss this project further please contact: Professor Stefan Kasapis ([email protected]) 1st Supervisor – Office 201.06.09 Dr. Taghrid Istivan ([email protected]) 2nd supervisor - Office 223.01.30A





Developing super hydrophobic biodegradable packaging films mimicking lotus effect

Biosciences and Food Technology/ Manufacturing, Materials and Mechatronics Engineering (School of Engineering) and CSIRO Manufacturing – RMIT Bundoora West

Project Description

Structure, composition, morphology and design of protective and supportive materials determine properties and performance. A source of innovations for materials is to observe and mimic natural materials that have evolved to optimize performance. Many materials such as composites, cellular structures and active surfaces have been designed and developed by comparison with natural materials, even when applications may differ. The science of copying natural materials is called biomimetics. The materials do not need to be the same, but generally the morphologies will be parallel. A widely used approach is to include oriented fibers in a polymer matrix, similar to plant cellulose fibres in lignin or pectin matrix. Another example is mimicking the nano-roughness of lotus leaves to create an apparent increased contact angle, and hence wetting resistance. A third example is laminated structures containing hexagonal cells, like wood and bee-hives. In this project we propose to use biomimetics to create water-resistant packaging materials from an otherwise water absorptive biodegradable substrate.

Polyolefin based plastics are almost universally used in packaging applications. Despite their many advantages, they are non-biodegradable[1]. Many these plastic packaging materials are single-use and they are discarded within the first year of manufacture. It has been shown that these packaging materials are already spread deep in the seabed, remote and high altitude landscapes either in an intact form or as fragments [2,3]. Not only the main plastic resin, but also the plasticizers used in these packaging are shown to be harmful to biota[4]. It has been shown that these plastics and their fragments are causing irreparable damage to the earth’s surface. The prospect of recycling of these materials is also not promising as most of them are not recyclable and need to be disposed of at landfills[5]. The leaching of toxic chemicals emanating from these plastics and the consequential impact to soil and ground water is equally negative[ 6]. These are the reasons why South Australia, Tasmania, Northern Territory and Australian Capital Territory in Australia have already banned single-use plastic bags and Queensland is banning them from 2018. Packaging industry is very important industry in Australia as it contributes about 1 % to Australian GDP. Australian food industry uses 65-70 % of total packaging materials. The aim is to mimick the ‘lotus effect’ observed in the nature. Nature creates super hydrophobic surfaces in aquatic plants such as lotus using this effect or mechanism [8]. Nanotechnological studies on ‘lotus effect’ (excellent hydrophobicity) has shown that micro to nanostructured lipophilic compounds are responsible for this hydrophobicity [9]. Mimicking nature, this project will harness the ‘lotus effect’ to innovate super hydrophobic packaging materials using starch as the substrate (main component), suberin as hydrophobic moiety and polyurethane (PU) as the linker or compatibiliser.

References

[1 Muscat, D., Adhikari B., and Adhikari R. et al. (2012. Journal of Food Engineering,109 (2):189-201. [2]. Barnes, D. K.A., et al. (2009). Philosophical Transactions of Royal Society, B. 364:1985–1998. [3]. Mato, Y. et al. (2001). Environmental Science Technology, 35: 318-324. [4] Oehlmann, J., et al. (2009). Philosophical Transactions of Royal Society, B, 364:2047–2062. [5] Song, J.H. et al. (2009). Philosophical Transactions of Royal Society, B, 364:2127–2139. [6] Teuten, E.L. (2009). Philosophical Transactions of Royal Society, B, 364 2027-2045. [7]]Halley, P., and Coote, M. (2017). The Future of Plastics. Nova, Australian Academy of Science (http://www.nova.org.au/earth-environment/future-plastics, accessed 13/07/2017). [8] Wagner, R. et al. (2003). Journal of Experimental Botany, 54(385):1295-1303. [9] Marmur, A. (2004). Langmuir, 20(9):3517-3519. Contact Details

1st Supervisor – Associate Professor Benu Adhikari, Ext 59940



Overcoming obesity through synergistic combination of Roselle hydroxycitric acid (HCA) and Roselle polyphenols

Biosciences and Food Technology Discipline/Pharmacy - School of Health and Biomedical Sciences – RMIT Bundoora West

Project Description

Obesity has become one of the most pervasive health problems, especially in economically prosperous countries including Australia[1]. Various metabolic disorders such as nonalcoholic fatty liver disease (NAFLD), insulin resistance, and hypertension are known to be associated with obesity [2,3]. Dietary obesity promotes liver inflammation and ultimately leads to liver damage [4]. Since obesity is linked to the consumption of high fat foods and also conversion of excess carbohydrates into fatty compounds in the body, it is necessary to find naturally occurring phytochemicals that reduce the absorption of fatty acids through the intestinal mucosa and also synthesis of fatty compounds in the body [5]. Some naturally occurring phytochemicals are known to possess antioxidant properties with effective anti-inflammatory, antiallergic, hepatoprotective, antithrombotic, antiviral, and anticarcinogenic activities [6]. Among them, Hydroxycitric acid (HCA), polyphenols such as resveratrol, catechins, and anthocyanins are of great interest due to their easy availability in plants and potent health-promoting activities including anti-obesity properties [7]. The polyphenols are able to form complexes with carbohydrate digesting enzymes (e.g. alpha amylase) and slow down the digestion of starch, thus help control obesity and type-2 diabetes.

Hibiscus sabdariffa L. (Hs), also known as roselle, is widely grown in many developing countries. It is also grown in Australia and is considered to be a native plant. This plant is water efficient and can be grown in arid land. Hs is a rich source of some valuable phytochemicals including HCA and polyphenols. It has been reported that [8] HCA can be used for short term weight loss and thus to reduce obesity. However, the magnitude of the weight loss effect is not fully known. Similarly moderate weight loss effect is observed when dietary polyphenols are used.

In this project, we hypothesise that a judicious or synergistic combination of HCA and polyphenols could produce a significant weight loss, at lower dose and help reduce or combat obesity The aim of this project is to determine the extent of weight loss by the HCA and polyphenols extracted from Hs, individually and in various ratios and to conclusively prove if synergistic effect on weight loss and combating obesity can be achieved.

References [1] Camp, H.S., D. Ren, and T. Leff. (2002). Adipogenesis and fat-cell function in obesity and diabetes. Trends in molecular medicine, 8(9):442-447. [2]. Groot, H.D. and Rauen, U. (1998). Tissue injury by reactive oxygen species and the protective effects of flavonoids. Fundamental & clinical pharmacology, 12(3):249-255. [3]. Holland, W.L., et al.. (2007).Inhibition of ceramide synthesis ameliorates glucocorticoid-, saturated-fat-, and obesity-induced insulin resistance. Cell metabolism, 5(3):167-179. [4]. Kim, S., et al. (2011). Resveratrol exerts anti-obesity effects via mechanisms involving down-regulation of adipogenic and inflammatory processes in mice. Biochemical pharmacology, 81(11): p. 1343-1351. [5] Pittler, M.H., and Edzard Ernst, E. (2004). Dietary supplements for body-weight reduction: a systematic review. The American Journal of Clinical Nutrition, 79:529–36 [6] Guo, H. and W. Ling, (2017). The update of anthocyanins on obesity and type 2 diabetes: experimental evidence and clinical perspectives. Reviews in endocrine & metabolic disorders, 2015. 16(1):1-13. [7] Jung, H.S., Y. Lim, and E.-K. Kim. (2014). Therapeutic phytogenic compounds for obesity and diabetes. International journal of molecular sciences, 15(11): p. 21505-21537, [8]Onakpoya, I., Hung, S.K., Perry, R. Wider, B., and Ernst, E. (2011). The Use of Garcinia Extract (Hydroxycitric Acid) as a Weight loss Supplement: A Systematic Review and Meta-Analysis of Randomised Clinical Trials. Journal of Obesity, 2011, Article ID 509038, 9 pages.

Contact Details 1st Supervisor – Associate Professor Benu Adhikari, Ext 59940



Valorization of dairy waste streams Food Technology Group

Bundoora

Bioscience and Food Technology Discipline / Applied Chemistry & Environmental Science Discpline –


Project Description

The dairy industry is a major contributor of liquid wastes to the environment. Whey has primarily been considered a waste by the dairy industry. Whey is the watery and thin liquid residual fraction of milk after coagulation and separation of caseins during yoghurt and cheese manufacturing [1]. This by-product cannot be simply disposed of due to its toxicity during decomposition, robbing rivers and streams of oxygen. Environmental regulatory issues triggered industry in finding pathways of utilising the whey waste streams. The increased production of different varieties of cheese and yoghurt products led industry in finding solutions apart from them being drying in producing powders to be used as food ingredients [2]. Waste minimization within the dairy industry can be categorised into three main areas; reduction in the generation of waste, reuse of waste materials/by-products and recycling of the waste materials by converting trash into food and cash. Thus, this project comprise of two major sections which can be carried out by two postgraduate students. One part of this project will focus on finding strategies in reducing the generation of whey at the point of origin. For this purpose, different membrane technologies such as ultrafiltration (UF), Microfiltration (MF) and Nanofiltration (NF), fortification methods with the use of different ingredients such as proteins, minerals, emulsifiers etc and use of advanced processing techniques such as ultrasound, high pressure processing and micro-fluidisation will be carried out. Doing so, the quality of certain secondary dairy products will be compromised. Thus, the physico-chemical, structural and functional characteristics of those novel secondary dairy products will be carried out. Fourier Transform Spectroscopy (FTIR), Circular dichroism (CD). Confocal Laser Scanning Microscopy (CSLM) and Scanning Electron Microscopy (SEM) are some of the advanced techniques that will be used within this project. Whey is an excellent source of functional proteins and peptides, lipids, vitamins, minerals and lactose [3]. These components have attracted much interest in transforming whey waste streams into a much more useful commodity built upon the strong consumer trend for health and wellbeing, and continuing discovery and substantiation of the biological functionality of whey constituents. Thus, the second major half of this project will focus on fractionating the individual components within the whey waste streams with the use of membrane technologies such as Ultrafiltration (UF), Nanofiltration (NF) and Reverse Osmosis (RO) and chromatographic techniques such as Ion-Exchange. Furthermore, the project will focus on finding the end uses for those fractionated components. For instance, some fractionated components will be inco-operted into secondary dairy products such as yoghurts, cheese, emulsions and dairy beverages with the use of encapsulation techniques. References

[1] Bozanic, R. et al. Austin Journal of nutrition and Food Sciences, 2 (2014) 1036-1043. [2] Nishanthi, M. et al. International Dairy Journal, 66 (2017) 76-83. [3] Smithers, G. International Dairy Journal, 18 (2008) 695-704.

Contact Details

To discuss this project further please contact: Dr Jayani Chandrapala ([email protected]) 1st Supervisor – Office 201.06.07




Functionality Modifications of Milk and Milk Products Bioscience and Food Technology Discipline / Applied Chemistry & Environmental Science Discpline –


Project Description

Milk is processed to minimize the risks associated with the presence of harmful microbial contaminants and enzymes thus extending the shelf-life by ensuring safety and stability. In addition, milk is processed to manufacture secondary dairy products with an acceptable palatability [1]. Heat treatment is one of the major dairy processing techniques, which involves some of the unit operations such as flow through pumps and piping, heat transfer in heat exchangers and homogenisation. Application of these techniques results in a number of physicochemical changes in milk, in particular denaturation and aggregation of the whey proteins. However, relatively little is known about the impact of mechanical forces accompanying the heat treatment, although milk is subjected to shear forces under some of the major unit operations of commercial milk processing such as pumping, stirring, or homogenisation. These shear forces acting upon protein molecules destabilise the native protein structure leading to unfolding, denaturation and subsequent aggregation [2]. For instance, the fluid drag associated with the shear flow destabilised the casein micelles resulting in structural transformations into more elongated shapes and unusual behaviour [3]. Moreover, shear can impact on the outer hydration sphere of proteins modifying the stabilising energy provided by the preferential hydration. This in turn could result in alterations of these hydration spheres leading to flocculation. Most of the studies related to shear and temperature induced changes are confined to pure individual proteins (mainly whey proteins) in aqueous solutions under specified conditions. The knowledge is lacking on the influence of both shear and temperature towards the protein structural changes in a complex protein mixture such as raw skim milk. This project will focus on evaluating the behaviour and structural modifications of native milk proteins in raw milk under various temperature and shear combinations that mimic common industrial applications. Shear forces will be generated with the use of ultraturax, micro-fluidisation, high pressure homogenisation and ultrasound. The treated samples will be analysed through Zeta sizer, Master sizer, Reverse Phase High Performance Chromatography, Rheometer, Fourier Transform Infrared Spectroscopy and Native and SDS Polyacrylamide Gel Electrophoresis. Furthermore, the present study will focus on the suitability of these treated samples under varying shear and temperature conditions towards the production of secondary dairy products such as yoghurts, cheese and dairy beverages.

References

[1] Corredig, M. et al. Food Research International, 29(1) (1996) 49-55. [2] De Kruif, C. et al. Advanced Dairy Chemistry—1 Proteins pp. 233-276 (2003): Springer. [3] Butler, P. D. et al. The Journal of Physical Chemistry, 100(2) (1996) 442-445.

Contact Details

To discuss this project further please contact: Dr Jayani Chandrapala ([email protected]) 1st Supervisor – Office 201.06.07




Compositional and Functional Stability of Thermally and Mechanically Processed Camel Milk

Biosciences and Food Technology Discipline- RMIT Bundoora

Project Description

Milk and milk products are considered one of the most nutritious foods of all, consumed by more than 6 billion people worldwide. World milk production has increased by more than 50% from 500 million tonnes to 769 million tonnes in the last three decades. In 2015-2016, the Australian dairy industry was worth $13 billion. Although cattle account for the largest proportion of global milk production, other milk producing animals (e.g. buffaloes, yaks, goats, sheep, camels, horses and donkeys) are also reared in various regions of the world to address climatic challenges, dietary traditions, and market demand.

Our research proposal relates to camel milk. Camels are reliable milk producers in harsh and dry conditions. There are an estimated 20 million heads globally, with most found in arid and semi- arid lands of Africa and Asia. Domesticated camels and their milk products represent an important source of food and income for local populations. In Australia, however, the majority of camels live in the wild, and considered pests as they cause damage to property and infrastructure and compete with livestock for food and water. With the population estimated at over 1 million and growing at an annual rate of 8%, local and federal governments have spent millions of dollars on culling programs. This natural resource has been underutilised until recently. A growing demand for camel milk and its products has been observed across the globe. Drive by health claims and medicinal properties, this trend has also emerged in Australia and certain entrepreneurial farms have started domesticating wild animals for farming and milking purposes.

Despite all that is known about bovine milk processing, this knowledge is only partially transferrable to camel milk, due to the significant differences in composition. Compositional studies of camel milk have shown a high variability among data published [3]. Such variation may result from factors such as geographic location, camel breed, feeding conditions, health status and physiological stage. Vast differences compared to bovine milk have also been reported. For example, camel milk fat consists of higher amounts of long chain polyunsaturated fatty acids; the whey protein to casein ratio is higher; and camel milk contains higher concentrations of bioactive compounds that exert antibacterial properties. It is also generally agreed that camel milk is devoid of β-lactoglobulin, which is a heat sensitive protein that plays an important role in dairy products manufacturing owing to its strong intermolecular interactions [2], [4]. However, as β-lactoglobulin has been found in one study [5], its presence cannot be confirmed. Apart from compositional differences, the proteins and fat globules in camel milk are also believed to be structurally different from those in bovine milk [1], [4], and consequently different methods would be required for processing. These vast compositional differences between camel milk and bovine milk must be understood in the local milk supply to tackle processing issues related to homogenisation and thermal stability.

With RMIT’s research excellence in advanced manufacturing and fabrication and biomedical and health innovation, together with its world standard research capability and the brand-new $15 million state-of-the-art Food Research and Innovation Centre equipped with the latest technologies, this project will aim to analyse and understand the compositional nature of Australian camel milk. By understanding the composition of Australian camel milk, the functional stability of thermally and mechanically processed camel milk will also be studied to develop strategies to aid processing and preservation and improve product quality by addressing the manufacturing challenges faced by the camel dairy industry nationally and globally.

References: [1] J. Barlowska, M. Szwajkowska, Z. Litwinczuk, J. Krol, Compr. Rev. Food Sci. Food Saf. 10 (2011) 291. (Review) [2]. A.K. Yadav, R. Kumar, L. Priyadarshini, J. Singh, Asian J. Dairy Food Res. 34 (2015) 83. (Review) [3]. G. Konuspayeva, B. Faye, G. Loiseau, J. Food Compos. Anal. 22 (2009) 95. (Review) [4]. Y. Hailu, E.B. Hansen, E. Seifu, M. Eshetu, R. Ipsen, S. Kappeler, J. Dairy Res. 83 (2016) 422. (Review) [5]. E.I. Elagamy, Food Chem. 68 (2000) 227.

To discuss this project further please contact: Dr Bogdan Zisu – 9925 9652; [email protected]




Understanding the Effects of Low Frequency Ultrasound on the Oxidative Stability of Milk Fat and Protein Solutions

Biosciences and Food Technology Discipline – RMIT Bundoora

Project Description

Milk proteins hold a prominent place in the food manufacturing industry and often used as powdered ingredients for their functional and nutritional contribution. Various powdered dairy ingredients including whey protein concentrate (WPC), whey protein isolate (WPI), milk protein concentrates (MPC), caseinates, whole- and skim-milk are often used as base materials in manufacturing. Subsequent use of these powders requires high solubility to ensure the overall high quality of the final product. In a recent RMIT research project, an ultrasonic processing technique applying low frequency (20 kHz) ultrasound was used successfully to improve powder solubility of WPC, WPI, MPC and caseinates when reconstituted [1].

Low frequency ultrasound generates acoustic cavitation which releases vast amounts of energy in the form of heat, pressure and shear forces. These physical shear forces were exploited in the RMIT project and solubility of reconstituted powders improved greatly at applied energy densities of 15, 30, 150, 300 and 400J/mL. Beyond the applied energy density of 150 J/mL, there was little change in solubility regardless of the protein solution, pH or concentration. There was no effect on the protein zeta potential, which is consistent with prior research findings, namely, that low frequency ultrasound has a physical effect on the system rather than a chemical effect [1]. However, depending on the ingredient source and energy density, a noticeable and unidentifiable smell was detected which suggests that unknown chemical reactions were indeed occurring beyond our understanding of this applied technology.

Recent studies have also indicated that free radical production generates volatile substances in sonicated dairy solutions after high and low frequency sonication [2, 3, 4]. In these studies, it is speculated that volatile formation is proportional to energy density, but again, these claims must be supported. Based on the research by Lo [11], we also believe these unknown chemical processes are in- part proportional to energy density but also depend on the product composition with lipids and proteins requiring attention. The pH of treated solutions as well as temperature during processing must also be accounted for.

This project aims to study the effects of low frequency (20 kHz) sonication on the oxidative stability of reconstituted milk protein solutions based on reconstituted WPC, WPI, MPC and Whole- and Skim-milks taking into account the composition, pH, and temperature with respect to applied energy density.

References: [1] Lo, B., Masters Thesis, 2017, Effect of low frequency ultrasound on the physical characteristics of milk proteins (in preparation for completion). [2] Characterisation of volatile compounds generated in milk by high intensity ultrasound. J. Riener, F. Noci, D.A. Cronin, D.J. Morgan, J.G. Lyng. International Dairy Journal, 19 (2009) 269-272. [3] Lipid oxidation volatiles absent in milk after selected ultrasound processing. P. Juliano, A.E. Torkamani, T. Leong, V. Kolb, P. Watkins, S. Ajlouni, T.K. Singh. Ultrasonics Sonochemistry, 21 (2014) 2165-2175. [4] Sensory characteristics and functionality of sonicated whey. S. Martini, M.K. Walsh. Food Research International, 49 (2012) 694–701.

Contact Details To discuss this project further please contact:

Dr Bogdan Zisu – 9925 9652; [email protected]


2018 School of science - RMIT University€¦ · School of Science HDR Project 2018 . Overcoming...

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