Q. In a chemostat, the feed flow rate and culture volume are 100 ml/h and 1.0 L, respectively. With glucose as substrate, the values of µmax and Ks are 0.2 h-1 and 1 g/L, respectively. For a glucose concentration of 10 g/L in the feed, the effluent substrate concentration (in g/L) is          Ans: 1 […]

Q. A microbial strain is cultured in a 100 L stirred fermenter for secondary metabolite production. If the specific rate of oxygen uptake is 0.4 h-1 and the oxygen solubility in the broth is 8 mg/L, then the volumetric mass transfer coefficient (KLa) (in s-1) of oxygen required to achieve a maximum cell concentration of

Q. An aqueous solution containing 6.8 mg/L of an antibiotic is extracted with amyl acetate. If the partition coefficient of the antibiotic is 170 and the ratio of water to solvent is 85, then the extraction factor is        Ans: 2 to 2

Q. 5′ capping of mRNA transcripts in eukaryotes involves the following events: P. Addition of GMP on the 5¢ end Q. Removal of g-phosphate of the triphosphate on first base at the 5¢ end C. 5′-5′ linkage between GMP and the first base at 5¢ end S. Addition of methyl group to N7 position of

Q. Match the industrial products mentioned in Group I with their producer organisms in Group II Group I                    Group II P. Citric acid            1. Trichoderma viride Q. Cellulase               2. Clostridium acetobutylicum R. Vitamin B12             3. Aspergillus niger S. Butanol           4. Propionibacterium freudenreichii   (A) P-4, Q-3, R-1, S-2 (B) P-3, Q-1, R-2, S-4   (C)