摘要
以枯草芽孢杆菌为试验菌株,研究不同Ca^2+源、Mg^2+源对固态发酵产纳豆激酶的影响。通过添加不同Ca^2+源、Mg^2+源的方式发酵制备纳豆,采用纤维蛋白平板法测定纳豆激酶活力,稀释涂布平板计数法测定纳豆中的活菌数,通过纳豆的颜色、香气、滋味和组织形态4个指标进行感官评价,分析不同的离子源对固态发酵产纳豆激酶的影响,筛选最佳的Ca^2+源、Mg^2+源制备纳豆。结果表明:在3种不同Ca^2+源中,CaCl 2为最佳Ca^2+源,添加量为0.04%(质量分数),制备的纳豆激酶活力最高,达到7786 IU/g,比空白组酶活力提高了57%,菌体量为5.4×107 CFU/g;3种不同Mg^2+中,MgSO4为Mg 2+源、添加量为0.72%(质量分数),制备的纳豆激酶活力最高,达到10591 IU/g,相比空白组提高了71%,菌体量达到7.8×10^7 CFU/g。
Effects of different Ca^2+sources and Mg^2+sources on nattokinase production by solid-state fermentation were studied with Bacillus subtilis as experimental strain.The fermentation of Natto was made by adding different Ca^2+and Mg^2+into the culture material,nattokinase activity was determined by fibrin plate method and the number of living bacteria in Natto was detected by dilution coating plated counting method.Sensory evaluation was carried out through 4 indicators of color,aroma,taste and tissue morphology.The effects of different ion sources on the production of nattokinase by solid-state fermentation were analyzed,and the best Ca^2+source and Mg^2+source were screened to prepare Natto.Among 3 different Ca^2+sources,CaCl2 was the best with a dosage of 0.04%.Nattokinase activity was the highest,reaching 7786 IU/g,57%higher than that of the control,and the biomass is 5.4×10^7 CFU/g;Among 3 different Mg^2+sources,MgSO 4 was the best with a dosageof 0.72%.Nattokinase activity reached 10591 IU/g,71%higher than that of the control,and the biomass was 7.8×10^7 CFU/g.
作者
孟健
陆丽霞
熊晓辉
MENG Jian;LU Lixia;XIONG Xiaohui(College of Food Science and Light Industry,Nanjing Tech University,Nanjing 211800,China)
出处
《生物加工过程》
CAS
2019年第6期651-656,共6页
Chinese Journal of Bioprocess Engineering
