What is Biotechnology ? The use of organisms to make products for man Raw materials Suitable organisms Usually micro-organisms Biotechnology processes Foods, enzymes, Antibiotics, fuels Sewage treatment Water 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 CO 2 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
Malting Before 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
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
Fermentation The wort is cooled and yeast is added The mixture is allowed to ferment until the yeast is killed by the alcohol
Yeast are facultative organisms- will grow with or without oxygen In the absence of O 2 , they live by fermentation. End products are alcohol (ethanol) and CO 2 In the presence of O 2 they live by respiration. CO 2 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 CO 2 CO 2 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”)
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
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.
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 biotechnological Processes to avoid contamination of pure cultures of other Microbes by unwanted types from the surroundings
PENICILLIN WAS DISCOVERED BECAUSE OF POOR BIOTECHNOLOGY PRECAUTIONS WHICH LED TO CONTAMINATED CULTURE PLATES IN ALEXANDER FLEMING’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 HYGIENE PRACTICE….
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 ?????
N 2 Nitrogen fixing bacteria in soil and nodules of plants Nitrates are made into proteins in plants NO 3 - Animals get their protein by eating Death and decay Bacteria break down the protein into nitrates NO 3 - 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 need For PHOTOSYNTHESIS
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 converted Into useful substances such as fuel and food…
Biogas utilisation Electrical energy Thermal energy Feeding in gas grid Biogas cleaning Biogas upgrading Cogeneration Cooking Lighting Cooling Heating Direct burning Vehicle fuel Spreading Gardening Agriculture Transport Energy crops, grass from Landscape maintenance (grass, maize, beets) Agricultural residues (manure, slurry) f e r m e n t a t i o n Bioenergy System with Liquid and Solid Feeding Storage Separation solid components become compost liquid components back to the fermentation or spreading
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 Engineering First, the nucleus of human cells are burst Human cell Nucleus
Genetic Engineering The chromosomes are cut up into small fragments and the required gene identified. Chromosome fragments Fragment containing required gene
Genetic Engineering Next the fragments are spread out and the required one isolated. Segment with required gene
Genetic Engineering Cytoplasm Bacterial chromosome Bacterial cell wall Plasmid Structure of a typical bacterium
Genetic Engineering Plasmid Plasmids are loops of DNA separate from the main chromosome .
Genetic 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 Engineering PLASMIDS ARE INSERTED INTO THE BACTERIA
Genetic Engineering Agar containing nutrients Colonies growing from single bacteria containing the plasmids with the human gene
Genetic Engineering These colonies will have the correct plasmid to produce the product from the human gene. Cells from this colony will be grown on a large scale and the medium analysed for the presence of the product from the human gene, eg Insulin