枯草芽孢杆菌Natto3的筛选及其降解黄曲霉毒素B_1的初步研究  

Study on isolation and degradation of aflatoxin B_1 of Bacillus Natto3

作　　者：张盼[1] 李培武[1,2,3] 万霞[1] 江木兰[1,3] 龚阳敏[1] 胡传炯[1,3] 丁小霞[1,2] 张银波[1] 

机构地区：[1]中国农业科学院油料作物研究所,湖北武汉430062 [2]农业部油料及制品监督检验测试中心,湖北武汉430062 [3]农业部油料作物生物学与遗传育种重点实验室,湖北武汉430062

出　　处：《中国油料作物学报》2015年第2期234-239,245,共7页Chinese Journal of Oil Crop Sciences

基　　金：国家自然科学基金面上项目(31270346)

摘　　要：从可食用的纳豆中筛选出一株能够高效降解黄曲霉毒素B1(aflatoxin B1,简称AFB1)的细菌,该细菌的发酵上清液经浓缩后制成的粗酶液对AFB1降解率达到91.4%。对该菌进行了分类地位鉴定并初步研究了粗酶液的酶学性质。结果表明,该菌经生理生化和16S r DNA序列比对鉴定为枯草芽孢杆菌,并命名为Natto3。Natto3的粗酶液降解AFB1的最适培养时间为72h,最适反应温度为37℃,最适p H值是8.5,Zn2+、Mn2+、Mg2+、Cu2+、Li+五种金属离子均会不同程度地抑制降解活性。此外,将该粗酶液添加在被黄曲霉毒素高度污染的花生样品中进行脱毒实验,可使花生中AFB1的浓度从192μg/kg降至43μg/kg。An unknown bacterial strain was isolated from the edible natto and this strain could effectively degrade aflatoxins B1（AFB1）. The degradation rate of AFB1 could reach 91. 4% with the concentrated crude enzyme solution prepared from the fermented supernatant. The strain was then taxonomic status identified and enzymatic properties of crude enzyme were investigated. Results were listed as follows： this strain was identified as Bacillus subtilis based on physiological,biochemical and 16S rDNA sequence analyses,thus named as B. subtilis sp. Natto3.The optimal growth time,reaction temperature,and pH value for the degradation of AFB1 by crude enzyme solution were 72 h,37℃ and 8. 5 respectively; the degradation activity could be inhibited to different extents by five metal ions including Zn^2 ＋,Mn^2 ＋,Mg^2 ＋,Cu^2 ＋and Li^＋. Furthermore,we added the crude enzyme solution into the peanut sample highly contaminated by AFB1,and examined whether AFB1 could be degraded. Detoxification experiment showed that AFB1 content in the contaminated peanut samples was decreased from 192μg / kg to 43μg / kg by the crude enzyme solution prepared from the culture of B. subtilis sp. Natto3.

关 键 词：纳豆 枯草芽孢杆菌 降解 AFB1 

分 类 号：Q939.9[生物学—微生物学]