高糖化力米根霉的筛选和鉴定  

Screening and Identification of High Saccharifying Rhizopus oryzae

作　　者：和晶晶 伍时华[1] 伍保龙[1] 王琨[1] 应玲云 夏杰[1] 黄翠姬[1] 易弋[1] 

机构地区：[1]广西科技大学生物与化学工程学院,广西柳州545006

出　　处：《中国调味品》2014年第10期1-6,14,共7页China Condiment

基　　金：广西科技厅项目(桂科攻0782003-2);柳州市科技局项目(2007021102)

摘　　要：为了筛选一株适用于糯米酒纯菌种酿造的高糖化力根霉,以不同酒曲为筛选源分离出19株根霉,经高糖化力测试从中筛选出一株28℃糖化3天产还原糖[(64.4±0.6)g/100g米、产葡萄糖(48.1±1.4)g/100g米]最高的根霉8-3M。通过对形态学和26SrDNA D1/D2区、ITS区序列进行分析鉴定,8-3M为米根霉(Rhizopus oryzae)。酶活力测试和酒精发酵测试表明:R.oryzae 8-3M在YPS液体培养基中28℃培养4天的粗酶液淀粉酶活力最高为(69.6±1.7)U/mL,在糯米饭中28℃培养96h的糖化酶活力最高为(36.8±2.0)U/mL、酒精度为(1.0±0.1)%(V/V)。因而R.oryzae 8-3M既能分泌淀粉酶,将绝大部分淀粉转化为可发酵性糖,又能将可发酵性糖转化为少量酒精,具有适用于糯米酒纯菌种酿造的潜力。In order to screen a high saccharifying strain of rhizopus that is suitable for pure culture of glutinous rice wine,19 Rhizopus spp.strains isolated from different solid starters are examined for their high ability to saccharify starch.Rhizopus 8-3M is selected as the functional Rhizopus strain with the highest reducing sugar [（64.4±0.6）g/100 g rice]and glucose production [（48.1±1.4）g/100 g rice]after cultured for 3 days at 28 ℃.Based on morphological test and phylogenetic analysis of 26S rDNA D1/D2 region and internal transcribed spacer （ITS）sequences,8-3M is identified as Rhizopus oryzae.Then the enzyme activity testing and alcoholic fermentation testing produced by R. oryzae 8-3M are studied.The highest amylase activity of crude enzyme solution from R.oryzae 8-3M in YPS broth for 4 days at 28 ℃ is （69.6±1.7）U/mL.R.oryzae 8-3M cultured in cooked glutinous rice for 96 h at 28 ℃ gives （36.8±2.0）U/mL of the highest glucosidase activity and （1.0±0.1）%（V/V）of ethanol content.Because of its ability of starch-degrading and small amount of ethanol fermentation, R.oryzae 8-3M may have a potential application in making defined fungal starter for glutinous rice wine.

关 键 词：米根霉 糖化酶 26SrDNA D1/D2 区 ITS区 

分 类 号：TS201.54[轻工技术与工程—食品科学]