Microbes In Human Welfare PDF

**MICROBES IN HUMAN WELFARE** **MICROBES IN HOUSEHOLD PRODUCTS:** - **Microbes convert complex food into simpler substances and alter the appearance, flavour odour and other qualities of food.** - **I.Lacto bacillus (bacteria): Lactic acid bacteria LAB for making curd and yoghurt Milk...

**MICROBES IN HUMAN WELFARE** **MICROBES IN HOUSEHOLD PRODUCTS:** - **Microbes convert complex food into simpler substances and alter the appearance, flavour odour and other qualities of food.** - **I.Lacto bacillus (bacteria): Lactic acid bacteria LAB for making curd and yoghurt Milk is converted to curd as it produces lactic acid that curdles milk. The small amount of curd added to milk contains millions of bacteria that curdle milk** - **Advantage: 1.Increases Vitamin B12** - **2.In our stomach checks the growth of disease causing microbes.** - **II. Fungus yeast: Saccharomyces cerevisiae anaerobic respiration produces CO~2~ and C~2~H~5~ OH** - **CO~2~ : leavens dough to make soft bread , batter of idli , appam- makes it soft** - **Ethanol : Toddy from palm sap and other beverages.** - **III.Microbes : fermented foods like fish , soya(tofu) and bamboo shoots** - **IV.Used for curing of cheese: Bacterium Propionibacterium sharmanii produces large holes for Swiss cheese.** - **Fungus Penicillium Roqueforti used to make blue chees from goats milk for Roquefort cheese.** - **MICROBES INDUSTRIES:** - **Fermentation can yield many products like beverages, vinegar, organic acids, vitamins , enzymes and antibiotics.** - **Fermented beverages: Depending on the type of material used for fermentation and type of processing various alcoholic drinks are produced** +-----------------+-----------------+-----------------+-----------------+ | **Beverage** | **Source** | **Microbe** | **Process** | +=================+=================+=================+=================+ | 1.Whiskey | Corn , Rye | *Saccharomyces | Distillation | | | | cerevisiae* | | +-----------------+-----------------+-----------------+-----------------+ | 2\. cider | Apples | *Saccharomyces | Distillation | | | | sp.* | | +-----------------+-----------------+-----------------+-----------------+ | 3.sake | Rice | *Saccharomyces | Distillation | | | | saki* | | +-----------------+-----------------+-----------------+-----------------+ | 4\. Beer | Barley malt | *Saccharomyces | No distillation | | | | sp* | | +-----------------+-----------------+-----------------+-----------------+ | 5\. Wine | Grapes | *Saccharomyces | No distillation | | | | cerevisiae* | | | 6\. Rum | Molasses | | Distillation | | | | *Saccharomyces | | | 7\. Brandy | Fruit juices | cerevisiae* | Distillation | | | | | | | 8.Vodka | Potato | *Saccharomyces | Distillation | | | | cerevisiae* | | | | | | | | | | *Sacharomyes | | | | | cerevisiae* | | +-----------------+-----------------+-----------------+-----------------+ - **CHEMICAL ENZYMES AND BIOACTIVE COMPOUNDS** - **Many microbes produce organic acids and chemical of commercial importance** - **Fungus *Aspergillus niger* : citric acid** - ***Acetobacter aceti* :acetic acid used in the manufacture of vinegar** - ***Clostridium butylicum*: Butyric acid** - **Lactobacillus : lactic acid for formation of curd and yoghurt** - **Fungus ,yeast: *Saccharomyces cerevisiae*: ethanol & *yeast Saccharomycopsis lipolytica* : lipase** - **Fungus a*spergillu*s species : pectinases and proteases &Bacillus sp: proteases** - **Lipases ,proteases enzymes remove oil stains from laundry and enzymes pectinases and proteases clear fruit juices that are produced commercially** - **Streptococcus produces streptokinase : clot buster to dissolve clots for myocardial infarction patients** - **Fungus *Trichoderma polysporum*: Cyclosporin A an immuno-supresent in organ transplant patients.** - **Fungus ,an yeast ,*Monascus purpureus*: Statins, cholesterol lowering agents** - **Substrate acted by enzyme forms cholesterol. statins act as a competitive inhibitor of the enzyme preventing the formation of cholesterol.** - **MICROBES IN ANTIBIOTIC PRODUCTION:** - **These are chemical produced by microbes that kill or inhibit the growth of other microbes** - **Anti=against bios = life as they kill microbes but from our point of view they are prolife** - **Discovered by Dr alexander Flemming while working on Staphylococcus bacterium which wer killed by the antibiotics produced by fungus *Penicillium notatum* and was called penicillin. Its true potential was established by Ernest Chain and Howard Florey for which they shared the Nobel Prize( 1945) with Flemming.** - ***Cephalosporium acremonium :* cephalosporin** - ***Streptomyces erythreus* : erythromycin** - ***Streptomyces griseus* : Streptomycin** - ***Streptomyces rimosus*: Tetracycline** - ***Streptomyces mediterranei* : Rifamycin** - ***Micromonaspora purpurea* : Gentamycin** - **Properties of a good antibiotic: 1. It should be harmless to the host without side effect** - **2. harmless to the symbiotic microflora in our intestine** - **3. It should be broad spectrum.** - **4. It should have quick action** - **A sewage treatment plant-STP- is a giant microbial breeding facility where the microbes oxidize the organic wastes and producei norganic chemicals like phosphates , nitrates which are later removed by tertiary treatment. In the STP pathogens are killed, and harmful chemicals are eliminated from the sewage before they are discharged into water bodies.** - **WORKING OF STP : 3 types of treatment takes place: Primary secondary and tertiary treatment of sewage.** - **I.Primary treatment: the process of filtration and sedimentation are used remove the suspended material. In the I step by sequential filtration, the floating debris are removed** - **After this the grit is removed by sedimentation.Primary sludge is what settles down and supernatant water is the effluent** - **II.Secondary treatment: involves aerobic bacteria in oxidation pond where there is an input of Oxygen and flocs into the effluent from the primary treatment. The effluent is constantly agitated mechanically in order to sufficiently aerate the water and promote vigorous growth of the aerobic bacteria.** - **Flocs: fungal mycelium with aerobic bacteria that forms a mesh.** - **Biochemical oxygen demand (BOD): The amount of oxygen that would be consumed if all the organic matter in one litre of water were oxidised.** - **.The aerobic bacteria digest the organic matter reducing the BOD of water & killing the pathogenic bacteria. When BOD is reduced the water is passed into settling tanks, where the bacterial flocs are allowed to settle down -what sediments : activated sludge. A part of this is pumped into the oxidation pond as inoculum.** - **Effluent from settling tanks is sent for tertiary treatment** - **Major part of the Activated sludge is pumped into :** - **III.Anaerobic sludge digesters: anaerobic bacteria degrade the sludge to form CH~4~, H~2~S, andCO~2.~ This forms Biogas** - **Effluent sent for tertiary treatment to remove toxic chemicals.** - **Biogas production:** - **Biogas is a mixture of gases is generated by methanogens acting on cellulosic material.We call them as Gobar gas plants and the technology of biogas production was developed due to the efforts IARI ( Indian Agricultural Research Institute) and KVIC ( Khadi and village Industries Commission** - **Methanogens are bacteria found in swamps and in the rumen of cattle** - **Therefore they will be found in cow dung which is the source of methanobacterium for the Biogas plant.** - **Raw material : any waste plant material which include domestic and agricultural wastes** - **Composition of Biogas consists of : CH~4~ = 50-68% ,CO~2~ = 25-35% ,H~2~ = 1-5% , N~2~ =2-7%** - **O~2~ =0-0.1%** - **Steps in Biogas production:1. Hydrolysis: Organic polymers are converted to monomers by bacteria like *Clostridium cellulosolvens* and *Eubacterium cellulosolvens*** - **2. Acid formation: In this process the monomers are converted to simple compounds like CO~2~, H~2~ , NH~3~ using acetogenic bacteria like *Acetivibrio cellulolyticus*** Floating Drum type biogas plant \| KVIC \| GTU \| Constant Pressure \... **PRODUCTION OF BIOGAS:** - **Process of biogas production:** - **A slurry made of crop and domestic waste is mixed with cow dung and fed into the concrete digester through the charge pit. The digester has a metal floating gas holder with an outlet pipe to remove the biogas, and a pit where the spent slurry can be collected to be used as manure.** - **As the biogas is generated by microbial activity, the gas holder keeps on rising. The out let pipe for the gas is connected by pipes to houses where the gas is used for cooking and lighting.** - **Advantages:** - **1.It is a storable form of energy which can be used when required.** - **2. It improves sanitation and minimises the spread of faecal pathogen** - **3. It is an eco friendly pollution free source of energy** - **4.It is used for cooking , lighting and for running tube wells.** - **5. The spent slurry is used ass manure for crop** - **MICROBES AS BIO CONTROL AGENTS:** - **Organic method of farming tries to ensure biodiversity in the cropland and hence will not try to eliminate pests but will keep the pest population in a manageable level. The organic believes that these pest are needed as they form the food of beneficial predatory and parasitic insects** - **Therefore it's better to use predators and pathogens of pest insects to control their population.Pesticides will cause pollution** - **Predators of insect pests.** - **Lady bird beetle preys on aphids and dragon flies on mosquito larvae** - **Bacterium Bacillus Thuringiensis --Bt- toxins kill insects belonging** - **lepidoptera , Coleoptera, Diptera. The bacterium is available as sachets** - **of dry spores which can be sprayed on the field. When the larvae feed** - **on the crop , the bacteria enter them and the toxin released kills** - **the pest. Scientist have also produced GM crops that contain the** - **gene for the toxin making the crop resistant too pest attack** - **Trichoderma are free living fungi that live in association with roots of crop plants. Fungus Trichoderma feed on plant pathogens that causes disease of crop plants and negate the use of chemicals to control them** - **Bacculovirus belonging to genus Nucleopolyhedrovirus are pathogens of insect pests and cause diseases in them. They are species specific, narrow spectrum, insecticidal bio-control agents. Kill only target pests and do not harm non target insects or plants, mammals, birds and fish. Excellent for IPM** - **Biofertilizers :these are organisms that enrich the nutrient quality of the soil. They do not pollute the environment as the chemical fertilizers do** - **Symbiotic association of Rhizobium leguminosorum with the root nodules of leguminous plants Fix atmospheric nitrogen as nitrates which can be absorbed by the plants** - **Azospirullum and acetobacter are free living bacteria that can do this.** - **Mycorrhiza are symbiotic association of fungal mycelium with the roots of Gymnosperm and Angiosperms.** - **Fungus Glomus forms mycorrhizae with roots of Gymnosperms.** - **Advantages for the plant:** - **1.Fungal partner absorb phosphorus and pass it on to the plant.** - **2.Such plants are more resistant to root borne pathogens.** - **3.They have greater tolerance to abiotic stress like drought or increased salinity.** - **4.There is overall increase in plant growth.** - **BIOFERTILIZERS** - **Cyanobacteria: Anabaena, Nostoc, Oscillatoria can fix nitrogen as nitrates which plants can utilise They are especially important in paddy fields** - **Advantages of biofertilizers over chemical fertilizers:** - **1.They are cheap and economical** - **2.They do not pollute the soil and some act as bio-pesticides** - **3.No fossil fuels are utilised in their production.** - **4.They are effective even in semiarid conditions and improve soil structure and function** - **5. They do not allow pathogens to flourish** - **6.They make available vitamins and other growth promoting substances** - **Harmful effects of Chemical fertilizer.** - **1.Agricultural run off from the crop lands contaminate water bodies leading to eutrophication & death of marine organism** - **2.It may also make drinking water unfit for consumption.** - **3.Chemical fertilizer being powdery do not bind the soil leading to a change in the soil structure.** - **4. They are far more expensive to manufacture than biofertilizers.** - **5. They are manufactured at the expense of already depleting resources of coal and petroleum.** - **6.They kill many useful organisms in the soil.** - **7.They enter the food chain and cause diseases at various trophic levels.** - **8.They affect the salinity of the soil.** - **INTEGRATED PEST MANAGEMENT-IPM** - **It is the practise of pest control through biological methods and use of chemical pesticieds to base minimum and only when essential.** - **1. To keep pest population under control by using their natural parasites, predators and parasitoids. Eg: Ladybird Beatles feed on aphid pest. Bacculovirus cause diseases in pests and kill them and Trichoderma cause diseases of plant pathogens and save the crop.** - **2. To use non-pollutant pesticides like pyrethrin and cinerin.** - **3. Growing pest resistant varieties of plants, like Bt cotton** - **4.Practise crop rotation , Mixed cropping etc to reduce pests.** - **5.A target crop preferred by the pest is planted away from the main crop so as to keep the pests away.** - **6. Improve soil condition, sanitation practises to reduce pests**