Preparation of nitrite reductase and method for preparing nitrite reductase preparation

Abstract

The invention discloses a preparation method of preparing nitrite reductase and preparing the preparation of the nitrite reductase, which belongs to the preparing technology field of biologic enzyme and enzyme preparation. Bacillus megatherium which can produce nitrite reductase is activated and prepared into seed, the obtained seed culture fluid is inoculate into a liquid ferment substrate by 1-10 percent of inoculation dosage; the initial pH value is 5.0-7.5, at 25-40 DEG C and 100-240r / min of rotation speed, after 20-36 hours of constant temperature cultivation, bacterial suspension is produced. Re-suspending the bacterial suspension by phosphate buffer can produce thalli. After the thalli is smashed by ultrasonic, the supernatant fluid is frozen and centrifugated, and then the rough enzyme solution is obtained. Nitrite reductases of different consistences and purities can be obtained after the rough enzyme solution is separated and purified. Liquid enzyme preparation can be prepared after enzyme protecting solute is added in the nitrite reductase. The enzyme activity of nitrite reductase preparation produced by using the invention is 4000-8000U / mL. The preparing method is simple, the production period is short, and public food safety can be maintained.

Description

technical field

[0001] The invention belongs to the technical field of preparation of biological enzymes and enzyme preparations, and more specifically, adopts fermentation technology to prepare a nitrite reductase capable of reducing nitrite and a preparation method of a nitrite reductase preparation. Background technique

[0002] Nitrite, as a food additive allowed by the National Food Sanitation Law, is widely used in meat processing. It reacts with myoglobin to produce nitrosomyoglobin, which is pink, giving meat an attractive color, that is, color development; at the same time, it can inhibit the reproduction of microorganisms, especially the inhibition of Clostridium botulinum Propagation, this bacterium can produce botulinum toxin, cause food poisoning, that is, antiseptic effect; it can also make meat products elastic, taste good, eliminate the peculiar smell of raw meat, and improve product quality. However, nitrite is also recognized as a carcinogen, which has gre...