Microbes In Human Welfare

The correct answer is option (D): (i-R); (ii-P); (iii-Q); (iv-S)
1. Propionibacterium Shermanni is a gram-positive bacteria. It is highly used in the production of Swiss cheese. This bacteria produces, acetate, propionic acid, and carbon dioxide as a by-product. 2. Saccharomyces Cerevisiae is widely used to produce ethanol through fermenting fruit juices. They have a probiotic activity and thus inhibit pathogenic bacterial growth. 3. Aspergillus niger is a workhouse for the production of citric acid. Microbial acid is an organic acid widely used in pharmaceutical food and beverages. 4. Trichoderma polypore produces cyclosporin A that acts as an immunosuppressor during organ transplant

The correct answer is option (B): Staphylococci
While working with Staphylococcus aureus, Fleming noticed that there was a contamination of fungus. The mold that was later known as Penicillium notatum stopped the growth of the bacteria. Penicillium works by inhibiting the production of peptidoglycan that is used in the cell wall. Earlier Fleming thought it was an enzyme but later discovered that it is an antibiotic.