41. The precursor used for the production of vitamin B12 by Streptomyces olivaceus is
A. cobalt chloride
B. cobalt sulfate
C. calcium chloride
D. calcium sulfate
42. Most biopolymers produced by micro-organisms are
A. cell wall constituents
B. nucleic acids
C. histones
D. exopolysaccharides
43. Microbial rennet, which is used in cheese manufacture is produced by
A. Mucor spp
B. Aspergillus spp
C. Bacillus spp
D. Saccharomyces spp
44. Production of L-lysine can be carried out by
A. C. glutamicum
B. B. flavum FA 1-30
C. B. flavum
D. All of these
45. The citric acid is recovered from the fermentation broth as
A. calcium citrate
B. magnesium citrate
C. zinc citrate
D. none of these