Question

Which of the following statements is correct?
A. Aspergillus niger is used for producing Cyclosporine A
B. Activated sludge is digested by anaerobic bacteria to produce carbon gas
C. Fleming, Chain, and Florey were awarded the Nobel prize for discovering penicillin
D. BOD is the amount of oxygen produced by bacteria on decomposition

Answer 1

Many products extracted from the microorganisms such as various species of fungi and bacteria are found to be used for producing different materials beneficial for human beings. These products can be used as medicines, as chemicals in fermentation, or in the production of various bioactive products.

Complete answer: Penicillin was the first-ever antibiotic to be discovered. The discovery of the drug was accidental, and it was extracted from the fungus Penicillium notatum. And was found to have killed the bacteria. While Fleming proved the antibacterial property of penicillin, Chain, and Florey purified and extracted the drug, thus making it possible to be produced in large amounts, thereby used to treat many bacterial infections. They were awarded the Nobel Prize in 1945 for its discovery and extraction.
Considering the other options-
-The fungus Aspergillus niger is commercially used in the production of citric acid by the process of fermentation. While Cyclosporin A which is used as an immunosuppressant drug is produced by the fungi Trichoderma polysporum by the process of fermentation.
-During the process of treatment of wastewater, especially in sewage treatment plants, the water is treated with bacterial flocs which convert the organic materials to produce sludge. The activated sludge by the action of anaerobic bacteria produces marsh gas or methane and not carbon gas.
-BOD or Biological Oxygen Demand is the amount of dissolved oxygen in a water body that gets used up by the microorganisms present in it. It is an indicator of the pollution level of the water body. The higher the BOD higher will be the pollution level.
Thus the most appropriate statement and the correct one is C, i.e., Fleming, Chain, and Florey were awarded Nobel Prize for the discovery of penicillin.

Note: Streptokinase which is a drug used for breaking down blood clots is also produced by a microorganism. It is produced by Streptococcus bacteria. The enzyme produced by the bacteria is responsible for the digestion of blood clots.