Extraction method of nisin

Abstract

The invention relates to the technical field of biochemical separation engineering, in particular to an extraction method of nisin. The method includes the following steps: (1) carrying out pH pretreatment on a fermented nisin fermentation liquid to obtain a pretreatment liquid; (2) filtering the pretreatment liquid by using a ceramic membrane to obtain a ceramic membrane clear liquid; (3) concentrating the ceramic membrane clear liquid by using a multi-effect evaporator to obtain a concentrated solution; (4) putting the concentrated solution into a solventing-out tank, and adding sodium chloride into the concentrated solution to obtain a salting-out solution; (5) adding n-butyl alcohol into the salting-out liquid for solventing-out, standing for more than 24 hours, and sequentially separating out a solvent layer, an emulsion layer and a water layer of the solventing-out liquid respectively; and (6) carrying out centrifugal treatment on the emulsion layer separated in the step (5) by using a tubular centrifuge to obtain a wet nisin product. According to the invention, the usage amount of the organic solvent and the usage amount of sodium chloride are effectively reduced, and the purity, the yield and the labor production efficiency of the product are improved.

Description

technical field [0001] The invention relates to the technical field of biochemical separation engineering, in particular to a method for extracting nisin. Background technique [0002] Nisin is a polypeptide antibacterial substance extracted from the fermentation product of Lactococcus lactis. It is a world-recognized safe and natural biological food preservative and antibacterial agent. In view of its high safety and excellent antibacterial performance, this antibacterial substance has been recognized by many national food regulatory agencies, and it has been included in the list of food additives. As the types of foods that nisin can be applied to continue to expand, it is favored by more and more food manufacturers. [0003] Since the discovery of nisin, researchers have successively developed extraction methods such as foam extraction, resin extraction, solvent extraction, bacterial cell adsorption and salting out. The foam extraction method requires simple equipment a...

AI Technical Summary

Problems solved by technology

The foam extraction method requires simple equipment and relatively low investment, but it has the disadvantages of low extraction efficiency and low product titer; although the resin extraction method can obtain products with high purity, its operation process control precision is high, resulting in More solid waste and other disadvantages; although the simple solvent extraction method can obtain higher titer products, it requires a large amount of solvent, which brings great environmental pollution and safety risks; the bacterial cell adsorption method requires continuous separation of bacterial cells , and the product is not completely separated from the thalline, which affects the extraction efficiency and yield, and the product purity obtained is not high; the salting-out method causes serious environmental pollution due to the use of a large amount of salts (such as ammonium sulfate, sodium chloride, etc.) , the purity of the obtained product is not high