1. Which of the following cannot be sterilized by steam?
a) Air
b) Water
c) Fermenter vessels
d) Fermentation media
Explanation: Air cannot be sterilized by steam. It can be sterilized by heat, filtration, UV radiation, gas scrubbing. The sterilization by heat and filtration the most common method used for air sterilization.
2. Which of the following is a typical aeration rate for aerobic fermentation?
a) 0.5 – 2 vvm
b) 1 – 2 vvm
c) 0.1 – 0.5 vvm
d) 3 – 4 vvm
Explanation: The typical aeration rate for aerobic fermentation is 0.5 – 2.0 vvm. Here, the first v stands for volume of air in liter. The second v stands for per unit of medium and m stands for per unit time in minutes.
3. 1% of phenol acts as ___________
a) Antiseptic
b) Disinfectant
c) Antibiotics
d) Antigen
Explanation: 1% of phenol acts as a disinfectant. Disinfectants are commonly used for killing or inhibiting bacterial growth. That is why phenolic compounds are used for chemical sterilization. 0.5% of phenol acts antiseptics.
4. What is the basic function of the fermenter?
a) To sterilize the medium
b) To recover the product
c) To provide optimum growth conditions to organisms and obtain the desired product
d) To purify the product
Explanation: The main function of the fermenter is to provide the optimum growth conditions for the growth of microorganisms and obtain the desired product. The recovery and purification of the product are the parts of downstream processing
5. While constructing the fermenter, which of the following is not required?
a) High-speed Agitation and Aeration system
b) Temperature control system
c) pH control system
d) Sample facilities
Explanation: In designing and constructing the fermenter, the fermenter must be provided with adequate aeration and agitation system. The agitation speed should not be higher and must not cause damage to the microorganisms.
6. The largest diameter for glass fermenter is ____________
a) 50 cm
b) 70 cm
c) 60 cm
d) 80 cm
Explanation: The largest practical diameter for the glass fermenter is 60 cm. This was discovered by Cowan and Thomas in 1988. The glass containers were made up of borosilicate battery jars. The glass vessels must be sterilized before using them.
7. Which of the following is not the property of Chromium film?
a) Non-porous
b) Soluble
c) Self-healing
d) Continuous
Explanation: The Chromium film is non-porous, insoluble, self-healing, and continuous. If the film gets damaged then it gets healed by itself when exposed to air or an oxidizing agent.
8. Which of the following element does not enhances the property of stainless steel?
a) Nickel
b) Molybdenum
c) Silicone
d) Manganese
Explanation: Nickel, Molybdenum, Silicone, Tungsten are the elements used to enhance the property of stainless steel. Nickel enhances resistance and improves engineering properties. Molybdenum improves the resistance against halogen salts. Corrosion resistance is improved by tungsten and silicone and a few other elements.
9. The hazard group criteria were given by ___________
a) Collins
b) Winkler
c) Park
d) Frommer
Explanation: Collins in 1992 gave the criteria for placing non-genetically engineered organisms into a hazard group (1 to 4) to access risks. A detailed assessment of risk and ways to reduce it was given by Winkler and Park.
10. Collins hazard group criteria did not include _______________
a) The ease of prophylaxis and treatment
b) The routes of infection
c) The pathogenicity of a microorganism
d) The reproductive cycle of a microorganism
Explanation: Collins hazard group criteria did not mention about the reproductive cycle of microorganism. It included the routes of infection, the pathogenicity of the organism, ease of treatment, number of organisms required to initiate an infection, amount of organism used in the fermentation process, etc.