Numerical Values for Microbes in Human Welfare

1. Curd Formation:

• Lactobacillus converts 1 gram of lactose into 0.5 grams of lactic acid in 1-2 hours at 37°C.

2. Nitrogen Cycle:

• Nitrobacter converts 10-20% of nitrite into nitrates during nitrification.

3. Biogas Production:

• Biogas typically contains 55-75% methane, 25-45% carbon dioxide, and traces of other gases.

4. Antibiotics:

• Penicillin extracted from Penicillium notatum in 1928 had an antibacterial activity of around 16 units per milliliter.

5. Vaccine Production:

• One milliliter of Jonas Salk’s polio vaccine contains approximately 13,500 million killed poliovirus particles.

6. Sewage Treatment:

• In activated sludge treatment, 25-35% of wastewater is recycled as return sludge, while the rest undergoes biological treatment.

7. Microbes in Food:

• Fermentation of soybeans by Rhizopus oligosporus or Aspergillus oryzae produces tempe with a protein content of around 20-25%.

8. Biological Control Agents:

• Neem tree (Azadirachta indica) produces azadirachtin with an LD50 (lethal dose to 50% of the target pest population) of approximately 3-5 ppm.

9. Bioremediation:

• Microbes can degrade oil spills at a rate of approximately 0.1-0.5% of hydrocarbons per day.

10. Microbiology Techniques:

• Serial dilutions in microbiology are commonly done in 1:10 or 1:100 ratios.
• Colony counting or spectrophotometry is used to estimate the number of microbes in a sample.