MP Board · Class 12 · Biology · Microbes in Human WelfareDiscuss the applications of microbes in the production of household and industrial products. Provide specific examples of products derived from microbial fermentation and their respective microbial sources.

Introduction\nMicrobes are not only pathogenic agents causing diseases but are also immensely beneficial to human beings in various ways. Microbes and their products are utilized extensively in household preparations as well as large-scale industrial processes to benefit human welfare.

Microbes in Household Products

1. Curd Production: Lactic Acid Bacteria (LAB) such as Lactobacillus grow in milk and convert it into curd. LAB produce acids that coagulate and partially digest the milk protein casein. Curd also improves nutritional quality by increasing vitamin B12.
2. Dough Fermentation: The puffed-up appearance of dough used to make foods such as dosa and idli is due to the production of carbon dioxide gas by the activity of yeasts during fermentation.
3. Bread Making: Baker's yeast (Saccharomyces cerevisiae) is used for fermenting bread dough, releasing carbon dioxide which makes the bread porous and soft.
4. Cheese Production: Different varieties of cheese are known by their characteristic texture, taste, and flavor, the specificity coming from specific microbes. For example, Swiss cheese has large holes due to production of a large amount of carbon dioxide by Propionibacterium sharmanii, and Roquefort cheese is ripened by fungi.

Microbes in Industrial Products

1. Fermented Beverages: Beverages like wine, beer, whisky, brandy, or rum are produced on an industrial scale by fermenting malted cereals and fruit juices using brewer's yeast (Saccharomyces cerevisiae).
2. Antibiotics: Antibiotics are chemical substances produced by some microbes that can kill or retard the growth of other disease-causing microbes. Alexander Fleming discovered penicillin from Penicillium notatum.
3. Chemicals, Enzymes, and Bioactive Molecules:
   • Organic acids such as citric acid (Aspergillus niger), acetic acid (Acetobacter aceti), and butyric acid (Clostridium butylicum).
   • Enzymes like lipases used in detergent formulations and streptokinase produced by Streptococcus used as a 'clot buster'.
   • Bioactive molecules like Cyclosporin A (immunosuppressive agent) produced by Trichoderma polysporum and statins (blood-cholesterol lowering agents) produced by Monascus purpureus.