北极海洋细菌Pseudoalteromonas sp.2018抑菌活性及其代谢产物研究

摘要

从2014年第六次中国北极科学考察采集的海洋沉积物中,分离获得了具有抑制农作物病原真菌活性的菌株Pseudoalteromonas sp.2018.测定了该菌株对病原真菌的抑制范围和对黄瓜白粉病的大棚防治效果,并对该菌株代谢产物通过硅胶色谱、凝胶色谱及半制备 HPLC 等进行分离纯化,通过质谱(MS)、氢谱(1 H NMR)和碳谱(13 C NMR)等进行结构鉴定.研究结果表明,Pseudoalteromonas sp.2018 菌株对辣椒疫霉(Phytophthora capsici)、褐孢霉(Fulvia fulva)、链格孢(Alternaria alternata)、黄瓜专化型尖孢镰孢(Fusarium oxysporum f.sp. cucumerinum)、番茄专化型尖孢镰孢(Fusarium oxysporum f.sp.lycopersici)和细极链格孢(Alternaria tenuissima)等具有抑制作用,对大棚黄瓜白粉病的防治效果达 66.7%;研究分离获得了环(脯-酪)二肽、环(脯-异亮)二肽、环(脯-亮)二肽和环(脯-苯丙)二肽,其中环(脯-酪)二肽和环(脯-亮)二肽对测试病原真菌的最小抑制浓度为125~500 μg/mL.该研究为极地微生物农用资源的开发利用提供理论参考.%Bacterium strain P seudoalteromonas sp.2018 was isolated from marine sediment collected during the sixth Chinese Arctic Research Expedition in the year of 2014,and this strain could inhibit the growth of several plant pathogenic fungi.Its antifungal spectrum and control effect on cucumber powdery mildew in a greenhouse were determined.Crude metabolites were extracted from the fermentation broth of the strain and were further separated, and purified copmpounds were obtained using silica gel chromatography,gel chromatography and semi-preparative HPLC chromatography.The structures of these compounds were determined via MS,1H NMR and 13C NMR.The results demonstrated that P seud-oalteromonas sp.2018 could inhibit Phytophthora capsici,Fulvia fulva,Alternaria alternata,Fusarium oxysporum f.sp.cucumerinum,Fusarium oxysporum f.sp.lycopersici,Botryosphaeria dothidea,Fu-sarium sporotrichioides,and Alternaria tenuissima.Its control effect on cucumber powdery mildew in greenhouse reached 66.7%.The structures of the metabolites were identified as cyclo(Pro-Tyr),cyclo (Pro-Ile),cyclo(Pro-Leu),and cyclo(Pro-Phe).The MIC values of cyclo(Pro-Tyr)and cyclo(Pro-Leu)a-gainst seven pathogenic fungi were determined as 125~500 μg/mL.Our study provides theoretical knowl-edge for development and utilization of agricultural resources from the polar environment.