Which of the following participates in the manufacturing of dextrans?

Neomycin is extracted from:

The antibiotic chloromycetin is prepared from . . . . . . .

Vitamin-$C$ was the first vitamin to be produced by a fermentation process using

The bottled fruit juices bought from the market are clearer as compared to those made at home. This is because the bottled juices are cleared by the use of . . . . . . .

An immunosuppressive agent used in organ-transplant patients is