Microbes in human welfare

Silage production, Biofuel production,
Biodegradation of agro-waste and Industrial production

1. Microbes in human welfare: Silage production, Biofuel production, Biodegradation of agro-waste and Industrial production Dr. S. PARTHASARATHY, M.Sc. ( Agri )., Ph.D. Assistant Professor (Plant Pathology )

2. Microbes in silage production Silage is high-moisture stored fodder produced by controlled fermentation which can be fed ruminants or used as a biofuel feedstock for anaerobic digesters . The crops most often used for ensilage are the ordinary grasses, oats, maize, sorghum, pearl millet, napier , and alfalfa etc . These crops are characteristically rich in soluble carbohydrates and have 50% to 60% moisture content. Undesirable microorganism Desirable microorganism

3. Undesirable microorganism Total aerobic bacteria Lactic acid bacteria Enterobacteria Yeasts and yeast like fungi Molds Penicillium ,  Fusarium ,  Aspergillus ,  Mucor ,  Byssochlamys ,  Absidia ,  Arthrinium , Geotrichum ,  Monascus ,  Scopulariopsis   and  Trichoderma Clostridia - Clostridium butyricum , Clostridium tyrobutyricum   Bacilli - Bacillus cereus Acetic acid bacteria Propionic acid bacteria

4. Desirable microorganism Commercial silage inoculants contain one or more strains of lactic acid bacteria ( LAB ), and the most common is Lactobacillus plantarum . Other bacteria used include Lactobacillus buchneri , Enterococcus faecium and Pediococcus species. Based on their sugar metabolism LAB can be classified as obligate homofermenters , facultative heterofermenters or obligate heterofermenters . Obligate homofermenters produce more than 85% lactic acid from hexoses (C 6  sugars) such as glucose, but cannot degrade pentoses (C 5  sugars) such as xylose. Obligate homofermenters are species such as  Pediococcus damnosus  and  Lactobacillus ruminis . Facultative heterofermenters also produce mainly lactic acid from hexoses, but in addition they also at least degrade some pentoses to lactic acid, and acetic acid and/or ethanol. Facultative heterofermenters include  Lactobacillus plantarum ,  L. pentosus ,  Pediococcus acidilactici ,  P. pentosaceus  and  Enterococcus faecium .

5. Microbes in Biofuel Production Biofuel includes solid biomass, liquid fuels and various biogases derived from plant or microorganisms or animal waste. Biofuels  are made from living things or the waste that they produce. One of the most common biofuels, ethanol, is produced from plants. The sugar can then be fermented (broken down) to ethanol by microbes such as the yeast Saccharomyces cerevisiae . Algae : Algae are the most commonly and recently used feedstock for biofuel production and present a positive hope for algae-derived fuel for the future. Eg . Pichia stapis Fungi : Saccharomyces cerevisiae , Zymomonas mobilis , Penicillum capsulatum  and  Talaromyces emersonii Bacteria : Clostridium acetobutylicum

6. Microbes in Agricultural Waste Management The principle of reducing waste, reusing and recycling resources and products (3Rs) aims at achieving efficient minimization of waste Bacteria involves in degradation of wastes: Bacillus pumilus and Mesorhizobium sp. Fungi involves in degradation of wastes: Pleurotus sajor-caju

7. Microbes in Household Production Microbes in food preparation: Lactobacillus Microbes as the source of food: SCP and Mushroom Microbes in Industrial Production Production of Alcoholic Beverages : The use of microbes in making fermented beverages is known since about 700 B.C. to Egyptians, Romans and Greeks. Saccharomyces cerevisiae var. ellipsoideus used in production of wine. Saccharomyces cerevisiae are used for fermentation of Beer. Organic Acid Fermentation : Organic acid Microbes used i) Citric acid Aspergillus niger ii) Gluconic acid Aspergillus niger iii) Fumaric acid Rhizopus arrhizus iv) Acetic acid Acetobacter aceti (Vinegar)

8. Vitamin Production : Vitamins are manufactured by fermentation technology using different microbial sources as given below. Name of the vitamin Microbial source i. Vitamin B2 Neurospora gossypii , Eremothecium ashbyi ii. Vitamin B12 Pseudomonas denificans iii. Vitamin C Aspergillus niger Antibiotic Production The first antibiotic was discovered accidentally by the British physician Alexander Fleming in 1929 when he was working with the pathogenic bacterium Staphylococcus aureus . Since then a number of antibiotics have been produced and used therapeutically. Some common antibiotics are listed below. Antibiotic produced Microbial source 1) Chloromycetin Streptomyces venezuelae ii) Erythromycin Streptomyces erythreus iii) Penicillin Penicillium chrysogenum iv) Streptomycin Streptomyces griseus

9. Gibberellin Production : Gibberellins are a group of growth hormones mainly produced by higher plants and fungi to promote growth by stem elongation. The first isolated by two Japanese scientists Yabuta and Sumiki in 1938 from rice seedlings infected with the fungus Gibberella fujikuroi .   Enzyme Production : Enzymes are biocatalysts, which either initiate or accelerate all biochemical processes in living organisms. Name of the enzyme Microbial source i) Invertase Saccharomyces cerevisiae ii) Pectinase Sclerotinia libertiana iii ) Lipase Rhizopus spp iv) Cellulase Trichoderma koningii   Dairy industry : The cheese , yoghurt, buttermilk, paneer etc required species of Streptomyces , Penicillium and Lactobacillus for fermentation.

10. Microbes can influence evolution of their hosts Microbes decides day to day activities of their hosts