Biotechnology

Living factories

What is Biotechnology ?

The use of organisms to make products for man

Raw materialsSuitable organisms

Usually micro-organisms

Biotechnology processes

Foods, enzymes, Antibiotics, fuels

Sewage treatmentWater purification

Where is it used

Brewing

Baking

Dairy Industry

Pollution control

Food Industry

Medicine

Biological detergents

Immobilised enzymes

Ancient Egyptians

Ancient Egyptians Noticed that when grapes were left a silvery dust appeared on them

On leaving them they also noticed they began to break down and leave a liquid behind

Alcohol

Biotechnology been used for thousands of years but was not given the fancy name

What is that dust ?

Yeast !!

It is a single celled fungus

It has no chlorophyll so it has to make its own food

Yeast feeds on the sugar in fruit and makes alcohol

Yeast

It is of great use in two major industries

Brewing

Baking

Baking

After the yeast has been added to the flour mixture the dough is kneaded

The mixture is left and we see the dough rise

The yeast produces CO2 which makes the dough rise

Baking

The dough can now be baked in a hot oven

Brewing

Add yeast to any fruit juice and we will see the yeast convert the sugar into alcohol

water

Fermentation

Glucose alcohol + Carbon Dioxide + Energy

In baking the alcohol evaporates

The above shows Anaerobic Respiration

Little Energy produced in absence of oxygen

Beer making

A very complex and series of controlled measure goes into making beer

There is no involvement of grapes – so how do the yeast get food for energy

The Barley grain

MaltingBefore the yeast can use the grain for food it must be malted

The starch is converted into simple sugars the yeast can break down

The barley is spread out in a large area where it is kept moist and warm and allowed to germinate

Germination sees the starch being broken down into sugar

Malt House

Mash

The germinated grains are killed by heat to prevent the sugar being used in germination

The grains are then crushed into a MASH

Water is added

As the sugar dissolves in the water it is sweet tasting

WORT

Wort Next ?

Extra sugar is added

Hops can be added to give flavour

Wort is boiled to kill bacteria

FermentationThe wort is cooled and yeast is added

The mixture is allowed to ferment until the yeast is killed by the alcohol

Storage

Stored in containers to allow it to mature

It is then filtered then ………

Packaged

Supplied to Consumer

Batch ProcessingRaw materialsNutrients fedInto vessel

Reactor vessel Fermenter

Microbes growing and bringing about fermentation process

Micro-organisms fed in

Product formed

Microbes no longer growing

Products and microbes removed separately

Finally

Yeast are facultative organisms-

will grow with or without oxygen

In the absence of O2, they live by fermentation. End products are alcohol (ethanol) and CO2

In the presence of O2

they live by respiration. CO2 is final product

Torula yeast. Candida utilis

Conditions favoring growth of yeasts: air, sugar, acid food, liquid, wide temperature range

Where yeasts are found: environments high in sugar -skins of fruits, nectar of flowers, surfaces of plants and mucous membranes of animals

Associations with humans:

Some yeasts are normal flora of the oral cavity, skin, GI tract and vagina

Useful fermentations

Saccharomyces cerevisiae is yeast that is used to ferment sugars to ethanol and CO2

CO2 is the desired end product of bread makers that leavens bread.

Ethanol is the sought after end product of brewers and winemakers.

Commercial yeasts for bakers, brewers and wine makers

Harmful associations -Agents of disease in humans and other animals

Candida albicans associates with humans in the mouth,intestine and vagina. It grows in most moist areas. It can cause disease under some conditions.

Candida albicans budding cells and colonies

Harmful associations -Agents of disease in humans and other animals

Candida causes thrush in the oral cavity, athlete’s foot,and is the most frequent cause of vaginitis in women.

Candidiasis in the oral cavity (thrush) and between toes (“athlete’s foot”)

Lactic Acid Bacteria• The main bacteria used in

manufacture of dairy products are commonly known as Lactic Acid Bacteria (LAB).

• The bacteria utilise the lactose in the milk to produce lactic acid.

Cheese Manufacture

Starters are used in the manufacture of cheese.

Main Types• Lactobacillus• Lactococcus• Leuconostoc• Streptococcus

Role of Lactic Acid• The fresh acidic flavour of

unripened cheese• Important to the formation

and texturising of the curd.• Produces volatile flavours • Synthesis of proteolytic and

lipolytic enzymes - important in cheese ripening.

• May influence micro-flora.

Cheese Ripening

• Most cheeses are ripened before consumption from 2 weeks for semi-hard Caerphilly to 2 years for parmesan.

• Ripened by enzymes derived from rennet, starter m/orgs, non-starter m/orgs and from the milk itself.

How do you make cheese?

• Normal produced from anaerobic fermentation from milk

• Involves fermentation of milk (lactose) by lactic acid bacteria (streptococcus)

Milk

(containing lactose)

Starter culture

Rennet added

Soft curd

Firm curd

Salting

Moulding and pressing

Ripening and maturation

The production of cheese

Cheese is produced from Milk ________ using anaerobic bacteria. Anaerobic bacteria respire without using__ Oxygen ______.The way in which cheese is made involves using a starter _ Culture ______ which is added to the milk and left for a

few hours to ferment at a temperature of _ 37degrees ____ C.

The soft curd is then _ Salted ______, moulded and pressed to make

the final cheese.

Fig A : Streptococcus used to make Edam Cheese

Yogurt

• A cultured dairy product• Soured by LAB• Role of LAB is to produce acid and

flavour compounds.• Mixed culture usually added to

develop different flavour profiles within the product.

Making yogurt

Milk containing lactose

Lactic acid bacteria added to the milk

Bacteria feed off lactose in milk

Lactic acid produced increases the milk acidity

Milk protein caesin thickens and coagulates to produce yogurt

The production of yogurt• Yoghurt is produced from MILK using

______. These lactic acid bacteria feed on the _______ in the milk and lactic acid is produced which increases the ______ of the milk. As this occurs the milk _______, called caesin, coagulates the milk and thickens producing yogurt!!! Flavouring and colouring can then be added.

BACTERIA ACIDITY LACTOSE THICKENS

SUMMARY….

• The souring of milk is a fermentation process

• Fresh milk contains sugars(lactose)and some bacteria

• The bacteria feed on the sugars• The lactose is converted into Lactic

acid by BACTERIAL FERMENTATION• The increased acidity makes the milk

turn sour

Sub Topic B…Problems with profit and waste…

WORKING WITH MICROBES

Microbes can be harmful…

• Useful microbes like yeast and Lactic acid bacteria are not harmful to humans.

• Some types of microbe are harmful though…

• They cause diseases

Scientists studying these harmful microbes MUST take precautions to STOPthem escaping and contaminating equipment….

..Sterile conditions are VITAL….

• Wear lab.coats,overalls,gloves and masks where necessary.

• Wash hands CAREFULLY.• Sterilise equipment and work

surfaces.• No food or drinks in the lab.• Careful disposal of microbes using

HIGH TEMPERATURES.These precautions are needed in all biotechnologicalProcesses to avoid contamination of pure cultures of otherMicrobes by unwanted types from the surroundings

PENICILLIN WAS DISCOVERED BECAUSE OF POORBIOTECHNOLOGY PRECAUTIONS WHICH LED TO CONTAMINATED CULTURE PLATES IN ALEXANDERFLEMING’S LAB…..BUT OF COURSE,MOST CASES OF CONTAMINATION ARE NOT USEFUL AT ALL…THEY CAN BE VERY HARMFUL….

EG MRSA IN HOSPITALS DUE TO POOR HYGIENEPRACTICE….

DANGER….SPORES !!!

• Precautions during manufacturing processes are very important as well..

• A particular danger can be SPORES from Bacteria and Fungi which are Resistant to normal hygiene measures

THEY CAN ONLY BE KILLED BY VERY HIGH TEMPERATURESIN AN AUTOCLAVE,OR BY CHEMICALS..

USING BACTERIA FOR DECOMPOSITION

• Decay is important as it recycles raw materials and gets rid of waste at the same time.

• Decay is the decomposition of ORGANIC matter by Micro-organisms

• They feed on the waste to provide themselves with ENERGY.

• During the process,both carbon and nitrogen are recycled

DO YOU REMEMBER THE CARBON AND NITROGEN CYCLES ?????

N2

Nitrogen fixing bacteria in soil and nodules of plants

Nitrates are made into proteins in plants

NO3-

Animals get their protein by eating

Death and decay

Bacteria break down the protein into nitrates

NO3-

Which can be taken back up by plants and made into proteins

Denitrifying bacteria use nitrates and release nitrogen into the air

Lightning and the addition of fertilisers also adds nitrates to soil

Nitrogen is returned to the soil so that plants can use it to produce new proteins..

Carbon dioxide reservoir in the air

Animals

Decomposers Plants

eating

respiration

respiration

death

death

respiration

photosynthesis

Carbon is recycled into carbon dioxide which plants needFor PHOTOSYNTHESIS

Kew Gardens compost heap…

…Britains’ largest!

What do we do with our waste then ?????

• Flushed away down the drains and sewers.

• Cannot be emptied into the water system

• Must be treated to be made safe

• Micro-organisms help to make sewage harmless to the environment.

Just flush it away ?

• Untreated sewage causes problems

• It LOWERS the oxygen concentration of rivers

• It also lowers their pH (makes acid rivers!)

• Causes diseases from the poisons,and harmful micro-organisms

Such diseases include Typhoid,Polio,Dysentry and Cholera !!

So what do we do then ?

• Use micro-organisms to breakdown the waste to produce products which are harmless to the environment

• They do this using their ‘decaying’action

• The micro organisms need LOTS of OXYGEN to do this

Why do you think this is ??

Its all to do with respiration..

• Lack of oxygen means ANAEROBIC respiration

• This means that the microrganisms will only partially breakdown waste

• Lots of oxygen allows AEROBIC respiration

AEROBIC respiration allows the COMPLETE breakdown of the waste material

Sewage Treatment-a summary.

National and local legislation regulates the quality of water that can be returned to the environment. A range of purification steps are required to meet the targets:

Consists of three stages:Primary treatment • Bulk physical removal of • suspended organic matter.

Secondary treatment • Microbial degradation to lower the organic content.

Tertiary treatment• Remaining organic pollutants and minerals removed.

Sewage Treatment

Whats in Sewage ??

• A wide variety of waste materials

• Different types of micro organism feed on different types of waste

• So a wide variety of Micro organisms MUST be provided so that ALL the waste can be broken down

THESE ARE SETTLEMENT TANKS WHERE OXYGEN IS ADDEDTO THE SEWAGE BY BIG ROTATING ARMS.WHAT IS THIS OXYGEN FOR ?

USEFUL PRODUCTS FROM WASTE MATERIALS

• BIOGAS (usually methane) can be produced from sewage sludge and domestic refuse.

• High quality PROTEIN foods from waste such as Whey(from cheese making) and fruit pulps (after juice extraction)

In this way,useless or poisonous substances are convertedInto useful substances such as fuel and food…

Biogasutilisation

Biogasutilisation

Electrica

l energy

Electrica

l energyTherm

al energy

Thermal

energy

Feeding in gas grid

Feeding in gas grid

Biogas

cleanin

g

Biogas

cleanin

g

Biogas upgradingBiogas upgrading

Cogeneration

Cogeneration

Cooking

Lighting

Cooling

Heating

Cooking

Lighting

Cooling

Heating

Direct burni

ng

Direct burni

ng

Vehicle fuel

Vehicle fuel

Spreading

Spreading

GardeningGardening

Agriculture Agriculture

Transport

Transport

Energy crops, grass from Landscape

maintenance (grass, maize, beets)

Agricultural residues (manure, slurry)

fermentation

fermentation

Bioenergy System with Liquid and Solid Feeding

StorageStorage

Separation

Separation

solid components become compost

solid components become compost

liquid components back to the fermentation or spreading

liquid components back to the fermentation or spreading

Profit from waste !!!

• The main aim in UPGRADING waste is to convert it to more useful substances

• Most commonly this involves raising the levels of PROTEIN,or increasing the ENERGY CONTENT of the waste

Just one more thing on fermentation…

• Some plant material can be used to produce ETHANOL by fermentation.

• Ethanol and Biogas have advantages over the use of fossil fuels such as oil and coal

• The raw materials are renewable and will not run out

Burning them produces less pollution than the fossil fuels

REPROGRAMMING MICROBES.

First of all….some Bacterial Genetics

• Bacteria have a chromosome which controls all of its activities

• Genetic engineering allows us to transfer pieces of chromosome from different organisms into bacteria

• This allows bacteria to make new substances

• This process involves several steps…..

How is it done ?

• Useful genes in other organisms are identified

• The required gene is separated from the chromosome

• The gene is inserted into the ‘host’ bacteria

• The bacteria reproduces containing the new gene

• Increased production of useful products results from this

THIS IS CALLED GENETIC ENGINEERING…

Genetic engineering vs. selective breeding

selective genetic• Single

characteristics not always possible

• Very slow..depends on animals/plants with relatively long life cycles

• Desired characteristic confined to one type of organism

• Single characteristic can be selected

• Very rapid..bacteria reproduce very quickly

• Characteristic can be transferred form one organism to another

More advantages of genetic engineering..

• Expensive and difficult to produce substances can be made cheaply and easily eg……..

• Insulin for Diabetes• Antibiotics such as

Penicillin• Vaccines for the

control of diseases

This is how its done………

Genetic EngineeringGenetic Engineering

First, the nucleus of human cells are burst

Human cellNucleus

Genetic EngineeringGenetic Engineering

The chromosomes are cut up into small fragments and the required gene identified.

Chromosome fragments

Fragment containing required gene

Genetic EngineeringGenetic Engineering

Next the fragments are spread out and the required one isolated.

Segment with required gene

Genetic EngineeringGenetic Engineering

Cytoplasm

Bacterial chromosomeBacterial cell wall

Plasmid

Structure of a typical bacterium

Genetic EngineeringGenetic Engineering

Plasmid

Plasmids are loops of DNA separate from the main chromosome.

Genetic EngineeringGenetic Engineering

By using special enzymes, we can make a cut in the plasmid DNA

Cut here

Next, we introduce the prepared HUMAN gene to the mixture. If all goes according to plan, the human gene will fit into the cut in the plasmid

Prepared human gene

Genetic EngineeringGenetic Engineering

PLASMIDS ARE INSERTED INTO THE BACTERIA

Genetic EngineeringGenetic Engineering

Agar containingnutrients

Colonies growing from single bacteria containing the plasmids with the human gene

Genetic EngineeringGenetic Engineering

These colonies will have the correct plasmid to produce the product from thehuman gene. Cells from this colony will be grown on a large scale and the mediumanalysed for the presence of the product from the human gene, eg Insulin

The need for Insulin is increasing…

• People are living longer• Populations are increasing• Diabetes often occurs at middle/old

age• Unhealthy lifestyles contribute to

diabetes• Better medical treatments mean that

people are living longer

So what's the problem then ?

• Purifying Insulin from the pancreas of slaughtered cattle and pigs is slow and expensive.

• Animal Insulin is not as effective as Human insulin.

• Some people are allergic to animal Insulin

• Many diabetics object to the use of a product from slaughtered animals…

And the solution ?• The insulin produced from bacteria

which have been genetically altered is pure Human insulin

• Its production is quick and inexpensive• It has non of the physiological and

ethical problems associated with the use of cattle or pig insulin

BUT….There are dangers involved with genetic engineering.It involvesCreating new strains of bacteria which MIGHT prove harmfulTo animals and plants……an ethical dilemma..

Biological detergents…

• Contain enzymes produced by bacteria

• Many of the stains on clothes are Proteins(blood,gravy,grass,etc)

• The enzymes break down and digest proteins

• They work at relatively low temperatures

• This saves energy and money

Disadvantages of Batch Processing

• Slow and Expensive….Fermenter has to be cleaned and sterilised between each product batch.

• Enzymes or micro-organisms cannot be recovered for use again at the end of each batch every time.

• Continuous flow processing solves these problems by relying on..

ENZYME IMMOBILISATION TECHNIQUES

Immobilised Enzymes..

• Restricts the movement of Enzymes or cells

• Usually by attaching them to beads of jelly or other carriers

• Keeps the enzymes/cells separate from the product

This results in increased productivity and reduced costscompared to batch processing

Antibiotics

• Chemicals which prevent the growth of micro-organisms.

• There are many different diseases caused by bacteria.

• Different bacteria are affected by different antibiotics

• One antibiotic may only work against certain types of bacteria

A range of different antibiotics is needed for the treatmentOf bacterial diseases

Production of antibiotics, most notably penicillin and the beta lactam antibiotics are produced by Penicillium molds

The penicillin is secreted by the mould and collected from the Nutrient jelly..