Fermentation Technology Multiple Choice Questions on “Fermentation Products Recovery and Purification – Chromatography”.
1. Which of the following is not a criterion for the choice of the recovery process?
A. Location of the product
B. Price of the product
C. Use of the product
D. Source of organismid5fdb57bb9f60c”
Answer: D
Clarification: The choice of the recovery process is based on criteria: The intracellular or extracellular location of the product, the concentration of the product, use of the product, properties of the product, quality of the product, bio-hazard of the product, impurities in the broth, price of the product.
2. Which of the following is not a stage of product recovery?
A. Removal of solids
B. Isolation of organism
C. Purification and concentration
D. Cell disruptionid5fdb57bb9f62d”
Answer: B
Clarification: The stages in product recovery include removal of solids from the fermentation broth, followed by cell disruption, followed by primary isolation, purification, and concentration of the product, and finally isolation of the product.
3. Which of the following is used in the precipitation of dextrans?
A. Methanol
B. PEG
C. Ammonium sulphate
D. Sodium sulphateid5fdb57bb9f63c”
Answer: A
Clarification: Organic solvents like methanol, ethanol can be used in the precipitation of proteins. This is due to the change in dielectric properties of the solution. Dextrans can be precipitated out of a broth by the addition of methanol.
4. Who employed the term ‘Chromatography’?
A. Tsvet
B. Archer
C. Richard
D. Erikaid5fdb57bb9f647″
Answer: A
Clarification: Mikhail Tsvet introduced the term ‘chromatography’. It is useful for the isolation and recovery of desired products. Tsvet in 1906 used chromatography to separate the pigments of the plants.
5. Which of the following is used to pack columns in adsorption chromatography?
A. Carbon
B. Silica gel
C. Potassium hydroxide
D. Aluminium oxideid5fdb57bb9f651″
Answer: C
Clarification: The materials used in the pack columns in the adsorption chromatography include inorganic adsorbents like aluminium oxide, aluminium hydroxide, silica gel, magnesium oxide, active carbon, etc.
6. The charged molecules can be separated by __________
A. Column chromatography
B. Ion exchange chromatography
C. Thin layer chromatography
D. Affinity chromatographyid5fdb57bb9f667″
Answer: B
Clarification: The charged molecules are separated by Ion exchange chromatography. It uses a charged stationary phase to separate the oppositely charged compounds. The oppositely charged particles will be attracted while the particles with the same charge will be eluted first.
7. Which of the following is not a gel filtration chromatography?
A. Molecular sieve
B. Gel permeation
C. Size exclusion
D. Gel residueid5fdb57bb9f671″
Answer: D
Clarification: The gel filtration chromatography is also called molecular sieve chromatography, gel permeation chromatography, size exclusion chromatography, gel filtration chromatography, or gel chromatography. Gel residue is not a gel filtration chromatography.
8. Which of the following stationary phase is not used in gel filtration chromatography?
A. Sephadex
B. Sephacryl
C. Bio-Gel
D. Resin beadsid5fdb57bb9f687″
Answer: D
Clarification: The resin beads are not used as stationary phase in gel filtration chromatography. Sephadex, Sephacryl, Bio-Gel, Sepharose, etc. are commonly used. The gel must be chemically inert and stable.
9. Which of the following is used to separate molecules based on affinity?
A. Column chromatography
B. Ion exchange chromatography
C. Thin layer chromatography
D. Affinity chromatographyid5fdb57bb9f691″
Answer: D
Clarification: The affinity chromatography is used in the separation of biological molecules based on their affinity with a particular substance. The molecules with low affinity with the stationary phase are eluted first and those with high affinity are recovered later.
10. Immunoaffinity chromatography is used for the purification of ____________
A. Lipoproteins
B. Interferons
C. Antibodies
D. Carbohydratesid5fdb57bb9f69b”
Answer: C
Clarification: Immunoaffinity chromatography is used in the purification of antibodies, antigens and the proteins of viral origin. The column contains gel and antigens against which antibodies have the most affinity. Thus, it helps in the purification of antibodies.
11. Which of the following dye is widely used in dye-ligand chromatography?
A. Methyl blue
B. Cibracron blue
C. Methyl orange
D. Malachite greenid5fdb57bb9f6a4″
Answer: B
Clarification: Dye-ligand chromatography uses a number of triazine dyes as ligands. The most widely used dye is Cibracron blue F3G-A. It is used for the purification of lipoproteins, interferons, coagulation factors, etc.
12. The HPLC uses the application of ___________
A. High temperature
B. Low temperature
C. High pressure
D. Low pressureid5fdb57bb9f6ad”
Answer: C
Clarification: The High-Performance Liquid Chromatography uses the application of high pressure, that is why HPLC is also known as High-Pressure Liquid Chromatography. The use of high pressure is to flow the solvent through the column of chromatography.
13. Chromatography is used to separate ____________
A. Complex mixture compounds
B. Simple mixtures
C. Viscous mixtures
D. Halogensid5fdb57bb9f6b6″
Answer: A
Clarification: The chromatography is used to separate a complex mixture of compounds. It is used for isolation and purification of the compound of interest from the mixture of compounds.
14. Thin Layer Chromatography is similar to Paper Chromatography.
A. True
B. Falseid5fdb57bb9f6bf”
Answer: A
Clarification: Thin Layer Chromatography or TLC is similar to Paper Chromatography. However, instead of using paper as a stationary phase the thin layer of adsorbents like silica gel, alumina, cellulose, etc. It has better separations than paper chromatography.
15. The Rf value is the ratio of distance travelled by solvent to the distance travelled by the solute.
A. True
B. Falseid5fdb57bb9f6c8″
Answer: B
Clarification: The Rf value or retention factor is the ratio of distance travelled by the solute to the distance travelled by the solvent. It indicates the relative rate of movement of a solute and the solvent.