直投式纳豆芽孢杆菌发酵剂的制备及应用效果

目的]优选出发酵制备纳豆激酶制品质量稳定、价格低廉的直投式纳豆发酵剂。方法]采用稀释平板分离法,从市售纳豆及纳豆菌剂中筛选出3株纳豆芽孢杆菌优势菌株。通过比较这3个分离菌株与实验室保存的纳豆芽孢杆菌菌株的产酶能力,优选出其中1株作为制备直投式纳豆发酵剂的菌种并研究其发酵工艺。结果]试验得出,实验室保存的纳豆芽孢杆菌产纳豆激酶酶活力最高。作为接种剂,直投式发酵剂在产酶活力上均优于液体种子液。试验优化了冻干粉菌悬液的浓度为107CFU/ml,发酵豆粕获得了498.8 U/g纳豆激酶酶活力。结论]研究可为利用直投式发酵剂发酵产纳豆激酶制品提供参考依据,为实际生产奠定基础。

Preparing Process of Bacillus natto Fermentation Agent for Direct Vat Starter and Its Application

Objective] To develop direct vat starter for producing nattokinase with stable quality and price moderate properties.Method] Three predominant strains were isolated from Japanese Natto and Bacillus natto agent for preparation of direct vat starter Bacillus natto starter with dilution plate method.One Bacillus natto strain,which has the capability of enzymes producing and suited for preparation of direct vat starter was obtained by comparison study of the three isolated strains and preserved in our laboratory.Result]From the result,as a inoculation,direct vat starter has the advantage of producing nattokinase than liquid seed.According to the optimized process,the nattokinase production of the fermented soybean meal was 498.8 U / g.Conclusion]The study will provide reference basis for using direct vat starter to produce nattokinase.