小豆内生真菌的筛选鉴定及其产玉米赤霉烯酮的可能性探究

Screening and identification of endophytic fungi of Vigna angularis and investigation of its potential to produce zearalenone

中文关键词:  小豆  玉米赤霉烯酮  镰刀菌  节菱孢霉  内生真菌

英文关键词:adzuki bean  zearalenone  Fusarium  arthrosporium  endophytic fungus

中文摘要:

      目的 筛选暴露玉米赤霉烯酮(zearalenone, ZEN)的小豆内生真菌, 并探索菌株潜在的ZEN产生风险。方法 以暴露ZEN的小豆为样本, 将分离纯化后的内生真菌进行经典形态观察; 同时扩增真菌核糖体保守序列ITS1、ITS4, 镰刀菌特异基因序列FU1、FU2确定小豆中镰刀菌种属, 同时通过ZEN产毒控制基因pks13进行聚合酶链式反应(polymerase chain reaction, PCR)扩增, 分析菌株ZEN合成的潜在风险。结果 共鉴别出3株镰刀菌, 其中2株初步鉴定为砖红镰刀菌(Fusarium lateritium)、1株为花腐镰刀菌(Fusarium napiforme), 未检测出ZEN合成关键基因; 1株玛利节菱孢霉(Arthrinium marii), 分子检测结果显示具有产ZEN毒素的可能性。将以上4株菌分别回接至添加小豆粉的培养基进行培养, 液相色谱-串联质谱法(liquid chromatography-tandem mass spectrometry, LC-MS/MS)未检测出ZEN毒素。结论 暴露ZEN的小豆具有内生镰刀菌, 存在可能产ZEN的内生节菱孢霉; 回接培养基未检测到ZEN, 但不排除小豆产生ZEN的风险。

英文摘要:

      Objective To screen endophytic fungi of adzuki bean exposed to zearalenone (ZEN), and detect the potential ZEN production risks of the screened strains. Methods Taking adzuki bean exposed to ZEN as a sample. The isolated and purified endophytic fungi were subjected to classical morphological observation, and the fungal ribosomal conserved sequences ITS1 and ITS4 and Fusarium-specific gene sequences FU1 and FU2 were amplified to determine the Fusarium species in the beans, while the ZEN production control gene pks13 was amplified by polymerase chain reaction (PCR) to analyze the potential risk of ZEN synthesis in the strains. Results Three Fusarium strains were identified, of which 2 were preliminarily identified as Fusarium lateritium and 1 as Fusarium napiforme, and the key genes for ZEN synthesis were not detected. One strain of Arthrinium marii had the possibility of producing ZEN toxin by molecular detection. The above 4 strains were spliced back into the media supplemented with adzuki beans flour, and no toxin was detected by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Conclusion There is endophytic Fusarium in ZEN-exposed adzuki beans, and there is endophytic Arthrinium marii which might produce ZEN, but ZEN is not detected in culture of backgrafting medium, but the risk of ZEN production by adzuki beans can not be excluded.