CAJ | 학술논문

为筛选能降解黄曲霉毒素 B1(AFB1)的细菌,对 AFB1污染的饲粮进行生物脱毒。以 AFB1结构类似物香豆素为唯一碳源和能源进行初筛,将含有标品 AFB1(500μg / L)的发酵液进行复筛,通过菌落形态观察、生理生化试验及16S rRNA 序列分析进行菌种鉴定,根据波长600 nm 处测定的菌液的吸光值大小进行培养基成分优化。结果表明,分离到1株稳定的 AFB1降解菌,通过形态、生理生化特征和16S rRNA 序列同源性分析鉴定,该菌株为甲基营养型芽孢杆菌 Bacillus methylotro-philus,命名为 WZ -4,该菌株16S rRNA 基因序列 GenBank 登录号为 KJ855772。在温度36℃、pH值7.0、接种量5%条件下,在含有500μg / L 的 AFB1发酵培养基中培养72 h,WZ -4菌的降解率为75.25%。该菌生长的最佳碳源为麦芽糖,最佳氮源为蛋白胨。0.05%的 Mg2+、Ca2+、Cu2+以及Fe3+对该菌株的生长均有抑制作用,其中 Mg2+的抑制作用最小,Cu2+的抑制作用最大。
위사선능강해황곡매독소 B1(AFB1)적세균,대 AFB1오염적사량진행생물탈독。이 AFB1결구유사물향두소위유일탄원화능원진행초사,장함유표품 AFB1(500μg / L)적발효액진행복사,통과균락형태관찰、생리생화시험급16S rRNA 서렬분석진행균충감정,근거파장600 nm 처측정적균액적흡광치대소진행배양기성분우화。결과표명,분리도1주은정적 AFB1강해균,통과형태、생리생화특정화16S rRNA 서렬동원성분석감정,해균주위갑기영양형아포간균 Bacillus methylotro-philus,명명위 WZ -4,해균주16S rRNA 기인서렬 GenBank 등록호위 KJ855772。재온도36℃、pH치7.0、접충량5%조건하,재함유500μg / L 적 AFB1발효배양기중배양72 h,WZ -4균적강해솔위75.25%。해균생장적최가탄원위맥아당,최가담원위단백동。0.05%적 Mg2+、Ca2+、Cu2+이급Fe3+대해균주적생장균유억제작용,기중 Mg2+적억제작용최소,Cu2+적억제작용최대。
To screen an aflatoxin B1(AFB1) degradation bacteria,the AFB1 pollutted feedwas detoxificated by biological way. At the first screening,AFB1 structural analogues coumarin was the sole carbon source and energy. The growing bacteria was selected in the nutrient solution with 500 μg / L AFB1 for the second screening. The species was identified according to the colony morphology observation, physiological and biochemical test and 16S rRNA sequence analysis. The medium components were optimized according to absorbance value at wavelength of 600 nm. The results showed that a stable AFB1 degradation bacteria was isolated and was identified as Bacillus methylotrophilus. The bacteria was named WZ-4 and its 16S rRNA gene sequence registration number in GenBank was KJ855772. The degradation rate of WZ-4 was 75. 25% when the temperature was 36 ℃,pH value was 7. 0,inoculation quantity was 5% ,AFB1 content was 500 μg / L and the fermentation time was 72 h. The best carbon source was maltose, and the best nitrogen source was peptone. 0. 05% Mg2 + ,Ca2 + ,Cu2 + and Fe3 + could inhibit the growth of the strain, Mg2 + had the minimal inhibitory effect,Cu2 + had the largest.