Method for preparing nattokinase by solid state fermentation method

Abstract

The invention discloses a method for preparing nattokinase by a solid state fermentation method. The method comprises unit operations such as soybean pretreatment, culture medium preparation, seed preparation, inoculation, temperature-variable fermentation, drying and smashing. The method is characterized in that the techniques such as raw material pretreatment, culture medium and seed preparation, inoculation, fermentation, drying and smashing are integrated; the whole process is performed in clean or bacteria-free environment; poor phenomena such as flowing, overflowing, dripping and leaking cannot be generated; the GMP (good manufacturing practice) requirements can be easily met. Compared with a traditional method, the method has the following characteristics that the ingenious raw material pretreatment and multicomponent culture medium composition design provides a good material base for the growth of nattokinase producing bacteria; a surfactant is used, so that the generation and the secretion of the nattokinase are obviously improved; through the application of a temperature-variable fermentation method and process, the nattokinase yield is improved by 10 to 45 percent; the method is scientific; the process is reasonable and advanced; the environment protection is facilitated. The method can be widely applied to development and production of nattokinase and other relative products.

Description

technical field [0001] The invention belongs to the field of bioengineering and technology, and in particular relates to a method for preparing nattokinase by a solid-state fermentation method. Background technique [0002] Natto is the traditional fermented soybean food that Japanese people love most. Nattokinase (NK) is a kind of protease with various biological activities prepared by fermenting soybean. It has been studied extensively and deeply. Modern scientific research has shown that its structure is a linear amino acid chain without space folding, and its characteristic substrate is fibrin. The fibrinolytic activity is greater than that of plasmin, and the molecular weight is much smaller than that of urokinase and lumbrokinase, and can be absorbed by the intestine. According to reports, nattokinase can effectively dissolve thrombus, and also has various physiological functions such as reducing blood viscosity, inhibiting platelet coagulation, lowering blood fat and...

AI Technical Summary

Problems solved by technology

The classic method used to produce natto and nattokinase is to use soybeans as raw materials, soak, cook, and cool down to inoculate and ferment. However, the internal bacteria of soybeans are not easy to grow, and the yield will naturally not be too high; CN102586141B discloses A liquid fermentation method using soybean cooking water as the main raw material and supplemented with two kinds of inorganic salts as the medium. In this case, the utilization rate of raw materials is inevitably too low; CN103205409B discloses a kind of high-activity natto prepared from black soybeans Kinase method; CN106085991A discloses a method for preparing nattokinase by solid-state fermentation, which provides a method for preparing nattokinase with peanut meal as the main raw material; although the above-mentioned patent provides a variety of raw material options for the production of nattokinase And made a certain contribution to the improvement of enzyme production, but the pretreatment of raw materials is generally insufficient, the nutrient components of the medium used are not balanced or insufficient, the utilization rate of raw materials is low, the fermentation process optimization is insufficient or needs to be improved, and microbial growth It is not very vigorous, it is difficult to give full play to the enzyme production characteristics of natto bacteria, and the enzyme production efficiency is not high, etc.