16. In Corynebacterium glutamicum, tryptophan biosynthesis is regulated by the activity of

A. DAHP synthetase
B. Anthranilate synthase
C. Both (a) and (b)
D. Phosphoenol pyruvate

17. Invertase has its application in confectionaries to prevent crystallization of sugar. It is obtained from

A. A. oryzae
B. A. niger
C. S. cerevisiae
D. B. subtilis

18. The method used for obtaining citric acid as fermentation product are commonly known as

A. submerged aerated fermentation
B. stationary tray fermentation
C. both (a) and (b)
D. none of these

19. The organism used for the production of streptomycin is

A. Streptomyces rimosus
B. Streptomyces griseus
C. Streptomyces aureofaciens
D. Streptomyces erythreus

20. Which of the following is true about β-ionone, non-ionic detergent used in the β carotene fermentation medium?

A. It is a precursor of the β-carotene fermentation process
B. It is regarded as “steering” factor associated with bringing about the presence and activity of the enzymes responsible for the β-carotene formation
C. It is an inducer of β carotene fermentation process
D. None of the above