Read the following passage carefully and answer the given questions.
During anaerobic sludge digestion, bacteria produce a mixture of gases such as methane, hydrogen sulphide and carbon dioxide. These gases form biogas and can be used as source of energy as it is inflammable. The bioactive molecule, cyclosporin A, that is used as an immunosuppressive agent in organ-transplant patients, is produced by the fungus Trichoderma polysporum. You must have noticed that bottled fruit juices bought from the market are clearer as compared to those made at home. This is because the bottled juices are clarified by the use of pectinases and proteases. Statins produced by the yeast Monascus purpureus have been commercialised as blood-cholesterol lowering agents. It acts by competitively inhibiting the enzyme responsible for synthesis of cholesterol. The BOD test measures the rate of uptake of oxygen by micro-organisms in a sample of water and thus, indirectly, BOD is a measure of the organic matter present in the water.
Statins, used as blood-cholesterol lowering agents are produced by -
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Monascus purpureus
Statins are drugs that lower the level of cholesterol in the blood. They act by competitively inhibiting the enzyme that makes cholesterol in the body.
Option (1) Saccharomyces cerevisiae — Incorrect. This is baker’s or brewer’s yeast. It is used to make bread and for the commercial production of ethanol. It does not make statins.
Option (2) Trichoderma polysporum — Incorrect. This fungus produces cyclosporin A, a drug used as an immunosuppressant after organ transplants.
Option (3) Monascus purpureus — Correct. This yeast is the source of statins, which have been sold as blood-cholesterol lowering agents.
Option (4) Staphylococci — Incorrect. Staphylococci are bacteria. Alexander Fleming was growing them when he saw that the mould Penicillium stopped their growth; this led to penicillin. They make no statins.
Note 1: The passage is taken from NCERT. NTA has put lines of the NCERT text together to make it. Most CUET (UG) questions come straight from NCERT, so study the book line by line, including figures and their titles.
Note 2: A similar question was also asked in CUET (UG) 2026 on 26-05-2026 (Slot 2), and in CUET (UG) 2025 on 20-05-2025 (Slot 1).