CYANOBACTERIA – Habitat, Isolation,

Purification and Mass Multiplication- for

M.Sc. Sem. II

By Dr. Kh. An. CMSC, LNMU

CYANOBACTERIA

Formerly BGA with division Cyanophyta (Cyano = Blue)

Free living Photosynthetic Aerobic Prokaryotes (More close to

bacteria rather than algae), with 70S ribosome, gm –ve features

Fresh water aquatic with internal thylakoid membranes

May be the ancestors of today’s endosymbiotic all 3 plastids

Played critical role in earth’s formation and rusting of earth by

causing great oxygenation event and ended anaerobicity

Can clean the environment, Fix Nitrogen, photoautotrophic,

precursor of chloroplast, can repair DNA, can cause genetic

transformations, played role in earth’s feasible environment

formation, can provide dietary supplementation………but….some

produce lethal toxins & can make water unpleasant also

Structure of typical CYANOBACTERIA

Structure of Phycobilisome (PBS)

Economic importance of CYANOBACTERIA

Spp. like Spirulina can be grown in tanks, produce protein

supplements

Spp. like Lyngbia can produce antibiotics

Can develop symbiotic relationship with protozoa, fungi and

plants. Spp. like Nostoc and anabaena can fix atmospheric nitrogen

with the help of heterocysts

Large colonies of Nostoc is even edible

Help in reclamation of alkaline soil

Osicllatoria etc can act as pollution indicator

Super BGA (single celled cyanobacteria) can form expensive scum

& produce food containing 60% protein, having all essential amino

acids in perfect balance

Many more…Hence preferably cultured and cultivated

D.B.T. Centre of U.P. (Lucknow) has reported the increase

in yield of paddy (about 12.5 q/ha) to be due to cyanobacterial

biofertilizer

For outdoor mass cultivation of cyanobacterial biofertilizers, the

regional specific strains should be used

Many germplasm collection laboratories have been established by

the D.B.T. in different parts of the country for the development of

starter inoculum

Mixture of 5 or 6 regional acclimatized strains of cyanobacteria, e.g. species of Anabaena, Aulosira, Cylindrospermum, Gloeotrichia, Nostoc, Plectonema, Tolypothrix are generally used for starter inoculum

The following four methods are used for mass cultivation : (i) cemented tank method., (ii) shallow metal troughs method, (iii) polythene lined pit method, and (iv) field method

The polythene lined pit method is most suitable for small and

marginal farmers to prepared algal biofertilizer

In this method, small pits are prepared in field and lined with thick

polythene sheets

Mass cultivation of cyanobacteria is done by using any of the four

methods under the following steps:

Prepare the cemented tanks, shallow trays of iron sheets or

polythene lined pits in an open area. Width of tanks or pits should not

be more than 1.5 m. This will facilitate the proper handling of culture

Transfer 2 -3 Kg soil (collected from open place for lm 2 area of the

tank) and add 100 g of superphosphate. Water the pit to about 10 cm

height. Mix lime to adjust the pH 7. Add 2 ml of insecticide e.g.

malathion to protect the culture from mosquitoes. Mix well and allow

to settle down soil particles

When water becomes clear, sprinkle 100 g of starter inoculum on the

surface of water

When temperature remains between 35-40° during summer, optimum

growth of cyanobacteria is achieved. Always maintain the water level

to about 10 cm during this period

After drying, the algal mat will get separated from the soil and forms

flakes. During summer about 1 kg pure algal mat per m2 area is

produced. These are collected, powdered, kept in sealed polythene

bags and supplied to the farmers

The algal flakes can be used as starter inoculum if the same process

is repeated

Cyanobacterial biomass can complement agricultural crops for the production of food, feeds, fuels, and chemicals

Production of biomass at large scale is required for the application of cyanobacteria. Cyanobacterial cultivation does not compete for resources with agricultural crops, and moreover, they have better aerial productivity than plants (Dismukes et al., 2008; Cañedo and Lizárraga, 2016; Ooms et al., 2016)

Genetic modification of cyanobacteria and their usefulness have been studied mainly in the laboratory; however, for commercial production, the process needs to be standardized and applied outdoors

Mass Cultivation of Cyanobacteria

The idea of high-rate (non-nutrient limited) large-scale (>50 L) cultivation of cyanobacteria and microalgae was proposed in early 1950s (Cook, 1951)

The recent demand of cyanobacteria and other microalgae in bioenergy, food, and valuable chemicals production sector has necessitated their large-scale cultivation

Economic sustainability is the most critical factor which determines the success of large scale biomass production and its downstream processing for the production of different commercial products

Mass Cultivation of Cyanobacteria

Light, pH, temperature, carbon dioxide, and nutrient supplements are the five critical abiotic parameters which determine the success of any growth system designed for autotrophic growth of photosynthetic organisms (Pulz, 2001; Flynn et al., 2010)

However, tremendous expertise and resources are required to manage all these closely linked factors

Therefore, only few cyanobacteria and microalgae such as Arthrospira, Chlorella, Haematococcus, and Dunaliella have been cultivated on large scale as economically and commercially viable crops (Rosenberg et al., 2008)

Mass Cultivation of Cyanobacteria

https://www.slideshare.net/sivaramKrishna13/srkblue-green-algae-and-their-mass-multiplication

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC182968/pdf/aem00058-0182.pdf

https://www.slideshare.net/ShraddhaChavan1/cyanobacteria

http://www.researchjournal.co.in/Online/AJES/AJES%2013(1and2)/13_23-25_A.pdf

https://biocyclopedia.com/index/biotechnology/plant_biotechnology/biofertilizers/biotech_blue_green_algae.php

https://www.frontiersin.org/articles/10.3389/fenvs.2018.00007/full

Dr. Kh. An. CMSC