Question

Which of the following is not a step involved in purification?

(a) Precipitation

(b) Dialysis or ultrafiltration

(c) Chromatographic techniques

(d) Freezing technique

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Origin of the question is Enzymes Purification topic in section Enzymes Purification of Enzyme Technology

Answer 1

Right answer is (d) Freezing technique

The explanation is: Freezing technique is a method wherein the cells are subjected to cold temperatures of about -15°C to -20°C. This is nothing but a cold or psychrophilic shock. It is a physical method for extraction of enzymes. Purification involves the following steps: precipitation, dialysis or ultrafiltration, chromatographic techniques and purity checking by chromatography or spectrophotometry.