Questions
During downstream process of penicillin fermentation, phosphoric acid or sulphuric acid is added to the medium to _________.
- kill all fungi
- lower the pH and convert penicillin to anionic form
- produce phosphate or sulphate salt of penicillin
- precipitate penicillin
Genetically engineered microorganisms are exploited now days for human advantage. “Superbug” is a term coined for genetically engineered microorganism which produces _________.
- hydrocarbon
- enzyme
- insulin
- antibiotic
A scientist produced an enzyme by microbial fermentation. He wanted to test it and thus, disintegrated it into its constituent parts: apoenzyme and cofactor. Each of the parts is heated for 3 minutes at 100°C. Subsequently, various combinations are tested for their ability to perform the enzymatic function. Which of the following combinations will retain its functionality?
- Unheated apoenzyme and unheated cofactor.
- Heated apoenzyme and unheated cofactor.
- Heated apoenzyme and heated cofactor.
- More than one of the above combinations is possible.
During fermentation, continuous feed is used to maintain __________.
- temperature
- cell number
- substrate concentration
- product concentration
A researcher observed zone of inhibition of a fungus among bacterial colonies. He presumed it to be due to antibiotic production, which is a _______.
- primary metabolite
- secondary metabolite
- tertiary metabolite
- quaternary metabolite
Torulopris utilis is a microorganism used _________.
- for production of third generation antibiotics
- for synthesis of citric acid
- as a flavouring yeast
- none of the above
Aeration and agitation is an important parameter in fermentation technology. In a stirring vessel, the power consumption by an agitator can be evaluated by __________.
- strain gauge attached to the shaft of agitator
- meter attached to the agitator motor
- dynamometer
- all of the above
During wine production, if aeration is done, which of the following organisms is likely to grow?
- Acetobacter
- Lactobacillus
- Yeast
- Penicillium
Food additives as amino acids are added in food because of its ______ nature.
- antibiotic
- antioxidant
- food preservative
- nutritive
Which of the following is produced by microbial fermentation and is used as a gelling agent?
- Biopolymer
- Fatty acid
- Amino acid
- Lipid
During brewing, hops are added during fermentation to provide a bitter flavour to the product. Which of the following in hops is responsible for providing the bitter taste?
- Tannins
- Flavonoids
- Phytosterols
- Beta resins
A researcher inoculated a bottle of fruit juice with yeast and left it open for few days. He observed that first C2H5OH + CO2 are produced and next CO2 + H2O are produced. Which of the following is correct inference of the process?
- The yeast uses alcohol for C and energy.
- The yeast utilizes glycolysis and then changes to fermentation.
- The yeast utilizes fermentation and then changes to respiration.
- None of the above is correct
Generation of foam is a serious problem during fermentation. Presence of which type of bacteria is likely to cause foam in a batch fed fermentation?
- Proteolytic bacteria<o:p></o:p>
- Lignin degrading bacteria<o:p></o:p>
- Fat degrading bacteria<o:p></o:p>
- Cellulolytic bacteria<o:p></o:p>
During fermentation by yeast in a fermenter, the alcohol produced is detrimental to yeast and eventually kills yeast. What can you do to reduce the alcohol production?
- Add buffer
- Add sugar
- Increase the pH
- Add oxygen
While making CO2 transfer from the bulk liquid to an air bubble inside a fermentor, which of the following step has the maximum resistance?
- While moving across the cell membrane of microorganisms<o:p></o:p><o:p></o:p>
- While moving through the bubble boundary layer<o:p></o:p>
- While moving through bulk fermentation medium<o:p></o:p>
- While moving through the liquid gas interface<o:p></o:p>
During antibiotic as erythromycin production by Streptomyces erythreus the following data was collected. 1 hour (100 cells, 0 erythromycin); 5 hours (1500 cells, 15 units erythromycin); 10 hours (25,000 cells, 35 units erythromycin); 15 hours (65,000 cells, 45 units erythromycin); 20 hours (64,000 cells, 60 units erythromycin); 25 hours (50,000 cells, 50 units erythromycin).
How many cells were present in the log phase of Streptomyces erythreus?
- 65,000
- 64,000
- 50,000
- 25,000
A flask containing 100 ml and a bioreactor containing 1 liter of nutrient, both were inoculated with 500 cells of a certain bacteria sp. The flask was incubated on mechanical shaker and aeration was introduced in bioreactor at 37°C for 2 hrs. The final pH in flask was found to be 5 with 105 cells/ml and that in bioreactor was 7 with 1012 cell/ml.
Which of the following is most apparent from the above statement?
- Bioreactors are better vessels for maintaining bacterial growth for a longer time.
- Bacteria does not like flasks.
- Flasks are better for acid production by fermentation.
- Flasks are bactericidal.
A flask containing 100 ml and a bioreactor containing 1 liter of nutrient broth were inoculated with 500 cells of a certain bacteria sp. The flask was incubated on mechanical shaker and aeration was introduced in bioreactor at 37°C for 2 hrs. The final pH in flask was found to be 5 with 105 cells/ml and that in bioreactor was 7 with 1012 cell/ml.
Calculate the generation time of that bacteria sp. In flask.
- 158 min
- 15.80 min
- 3.90 min
- 39 min
During antibiotic as erythromycin production by Streptomyces erythreus the following data was collected. 1 hour (100 cells, 0 erythromycin); 5 hours (1500 cells, 15 units erythromycin); 10 hours (25,000 cells, 35 units erythromycin); 15 hours (65,000 cells, 45 units erythromycin); 20 hours (64,000 cells, 60 units erythromycin); 25 hours (50,000 cells, 50 units erythromycin).
Which is the most suitable time for harvesting erythromycin?
- 10 hours
- 15 hours
- 20 hours
- 25 hours
Match the following organisms with their products produced by fermentation commercially
| Column I | Column II |
| A. Clostridium | 1. Acetone-Butanol |
| B. Bacillus licheniformis | 2. Amylase |
| C. Bacillus subtilis | 3. Bacitracin |
| D. Propinobacterium | 4. Vitamin B12 |
- A - 1, B - 2, C - 3, D - 4
- A - 1, B - 3, C - 2, D - 4
- A - 4, B - 3, C - 1, D - 2
- A - 2, B - 1, C - 4, D - 3