Golden Key Points – Chapter 8- Microbes In Human Welfare

Golden Key Points

1. Microbes in Household Products:

   • Microorganisms like Lactobacillus are used to convert milk into curd through fermentation.
   • Dough used for making foods like dosa and idli is fermented by bacteria, producing CO2 gas.
   • Baker’s yeast (Saccharomyces cerevisiae) is used for fermenting dough in bread making.
   • Traditional drinks and foods are made by fermenting various substrates using microbes.

2. Microbes in Industrial Products:

   • Microbes are used in industry to synthesize valuable products like beverages and antibiotics.
   • Industrial production often involves large-scale cultivation of microbes in fermentors.

3. Fermented Beverages:

   • Yeasts, like Saccharomyces cerevisiae, are used for fermenting malted cereals and fruit juices to produce ethanol.
   • Different types of alcoholic beverages are produced based on the raw material used and the fermentation process.

4. Antibiotics:

   • Antibiotics are chemical substances produced by microbes that can kill or retard the growth of other microbes.
   • Penicillin, the first antibiotic discovered by Alexander Fleming, revolutionized medicine.
   • Other antibiotics have been purified from various microbes and have greatly improved the treatment of infectious diseases.

5. Chemicals, Enzymes, and Other Bioactive Molecules:

   • Microbes are used in industry to produce various chemicals, enzymes, and bioactive molecules.
   • Examples include organic acids, alcohols, lipases, pectinases, streptokinase, cyclosporin A, and statins.

6. Microbes in Sewage Treatment:

   • Microbes play a vital role in treating sewage in sewage treatment plants (STPs).
   • Treatment involves physical removal of particles and biological treatment to reduce organic matter content.
   • Anaerobic digestion of sludge produces biogas, which can be used as a source of energy.

7. Microbes in Production of Biogas:

   • Methanogenic bacteria like Methanobacterium produce methane from organic material in anaerobic conditions.
   • Biogas plants utilize microbial activity to produce biogas from bio-wastes like cattle dung.

8. Microbes as Biocontrol Agents:

   • Biocontrol involves using natural predation and biological methods to control plant diseases and pests.
   • Ladybirds, dragonflies, Bacillus thuringiensis (Bt), Trichoderma, and baculoviruses are examples of biocontrol agents used to manage pests and diseases.

9. Microbes as Biofertilizers:

   • Biofertilizers, including bacteria, fungi, and cyanobacteria, enrich soil nutrients and promote sustainable agriculture.
   • Examples include nitrogen-fixing bacteria like Rhizobium and Azotobacter, mycorrhizal fungi, and nitrogen-fixing cyanobacteria like Anabaena.