一株高效降解玉米赤霉烯酮的耐酸耐高温枯草芽孢杆菌的研究

为寻求更高效、实用的生物脱毒制剂,提高其应用范围,通过采集酸性、高温的温泉环境样品,筛选获得1株高效降解玉米赤霉烯酮(ZEN)的细菌菌株Y-33,并对该菌株生长和降解特性进行分析。结果表明,菌株Y-33在50℃、pH值5.0条件下孵育36 h,菌液对2 μg·mL^-1 ZEN的降解率高达93.79%,对20 μg·mL^-1 ZEN的降解率也达82.40%。从形态、生理生化特性及16S rDNA序列对菌株Y-33进行分析,初步鉴定为枯草芽孢杆菌(Bacillus subtilis)。该菌株发酵上清液在28℃条件下对ZEN降解率为62.02%。金属离子Mn²⁺能明显增强菌株Y-33发酵上清液对ZEN的降解能力,降解率达81.17%,而Zn²⁺严重抑制了Y-33发酵上清液对ZEN的降解能力,降解率仅为5.42%。本研究结果为ZEN解毒菌剂的开发与应用奠定了理论基础。

Study on Heat Resistant Bacillus subtilis With High Degradation Efficiency of Zearalenone

To seek more efficient and practical biological detoxification strain to improve the application scope, we collected samples from acid and high temperature environment. One strain of bacteria named Y-33, was isolated for efficient detoxification zearalenone (ZEN),. Y-33 strain was incubated at 50℃ and pH value 5.0 for 36 hours, after which the degradation rate of bacterial solution to 2 μg·mL^-1 ZEN was as high as 93.79%, and up to 82.40% to 20 μg·mL^-1 ZEN. The strain Y-33 was initially identified as Bacillus subtilis with the analysis of its morphological, physiological and biochemical characteristics and 16S rDNA sequences. The degradation rate in fermentation supernatant of the strain's was 62.02% at 28℃. Metal ion Mn²⁺ could significanty enhance the degradation ability of strain Y-33 culture supernatant to ZEN with the degradation rate being 81.17%, while Zn²⁺ severely inhibited the degradation capability of ZEN by Y-33 culture supernatant to only 5.42%. The results of this study lay the theoretical foundation for the development and application of ZEN detoxifying microbes.