米曲霉奶酪发酵剂培养条件优化  

Optimization of Culture Conditions for Aspergillus oryzae Cheese Starter

作　　者：吴琛 陈旭[1] 李馨宁 史海粟 李彦博 王儒红 樊浩 陶冬冰[1] 武俊瑞[1] 乌日娜[1] 岳喜庆[1] WU Chen;CHEN Xu;LI Xin-ning;SHI Hai-su;LI Yan-bo;WANG Ru-hong;FAN Hao;TAO Dong-bing;WU Jun-rui;WU Ri-na;YUE Xi-qing(College of Food Science,Shenyang Agricultural University,Shenyang 110161,China;Liaoning Institute for Food Control,Shenyang 110031,China)

机构地区：[1]沈阳农业大学食品学院,沈阳110161 [2]辽宁省食品检验检测院,沈阳110015

出　　处：《沈阳农业大学学报》2020年第6期696-704,共9页Journal of Shenyang Agricultural University

基　　金：国家青年科学基金项目(31801567);辽宁省教育厅一般项目(LSNQN20124);沈阳农业大学博士引进人才项目(880417040)。

摘　　要：为研究可用作新型霉菌奶酪发酵剂的米曲霉最佳培养条件及其产中性蛋白酶和碱性蛋白酶最适条件,以前期筛选鉴定的豆酱优势米曲霉分别进行碳源、氮源、温度、p H值单因素试验,初步确定对米曲霉生长影响的显著因素。选取碳源、氮源和温度为优化因子,利用Box-Behnken响应面法优化米曲霉培养条件,确定米曲霉最佳生长的碳源含量、氮源含量和培养温度。在不同培养基组成、培养基pH值和培养温度条件下,通过荧光标记法测定米曲霉产中性蛋白酶和碱性蛋白酶活力,探究不同生长条件对米曲霉产蛋白酶活性影响,最终获得新型霉菌奶酪发酵剂的最佳培养条件和高产蛋白酶条件。结果表明:不同碳源和氮源中麦芽糖和酵母粉对米曲霉生物量影响最显著,对应生物量分别为(2.20±0.06)g·L^-1和(2.00±0.13)g·L^-1,与对照组相比分别提高22.20%和11.10%。优化因子对米曲霉生物量影响程度为:酵母粉>温度>麦芽糖。米曲霉在麦芽糖15.30g·L^-1、酵母粉11.60g·L^-1、温度30.80℃,p H值7.0培养条件下,生物量为(2.21±0.03)g·L^-1,较优化前提高57.86%。米曲霉在培养基组成C∶N=4∶1、pH值6.5、温度30℃条件下,中性蛋白酶活力为(508.2±0.4)U·g-1,较优化前提高69.49%;在培养基组成C∶N=4∶1、pH值7.5、温度为30℃条件下,碱性蛋白酶活力为(392.4±0.3)U·g-1,较优化前提高53.59%。此结论为米曲霉应用于霉菌奶酪制作奠定基础。In order to study the optimal culture conditions of Aspergillus oryzae,which can be used as a new mold-ripened cheese starter,and the optimal conditions for neutral protease and alkaline protease production.The soybean paste dominant A.oryzae,which was screened and identified in the previous stage,was used as the single factor test of carbon,nitrogen,temperature and pH value preliminarily determined the significant factors affecting the growth of A.oryzae.The carbon source,nitrogen source,and temperature were selected as optimization factors.The Box-Behnken response surface method was used to optimize the A.oryzae culture conditions to determine the optimal growth carbon content,nitrogen source content,and culture temperature of A.oryzae.Under different medium composition,medium pH and culture temperature conditions,the activity of neutral protease and alkaline protease produced by A.oryzae was measured by afluorescein isothiocyanate(FITC)-labeled casein assay,and the effect of different growth conditions on the activity of protease was explored.Therefore,the optimal culture conditions and high-protease conditions for the new mold-ripened cheese starter were obtained.The results indicated that maltose and yeast powder had the most significant effect on the biomass of A.oryzae in different carbon and nitrogen sources,and the corresponding biomass was(2.20±0.06)g·L^-1 and(2.00±0.13)g·L^-1.Compared with the control group,it increased by 22.20%and11.10%,respectively.The degree of influence of optimization factors on A.oryzae biomass was yeast powder>temperature>maltose.A.oryzae in the culture conditions of maltose 15.30 g·L^-1,yeast powder 11.60 g·L^-1,temperature 30.80℃,pH 7.0,the biomass is(2.21±0.03)g·L^-1,which is improved 57.86%.A.oryzae culture medium composition C∶N=4∶1,pH 6.5,temperature 30℃,neutral protease activity is(508.2±0.4)U·g-1,which is 69.49%higher than before optimization.Under the conditions of medium composition C∶N=4∶1,pH 7.5 and temperature 30℃,the activity of alkaline pr

关 键 词：响应面法 米曲霉 霉菌奶酪 优化 蛋白酶 

分 类 号：TS252.5[轻工技术与工程—农产品加工及贮藏工程]