红树林来源内生真菌杂色曲霉Aspergillus versicolor MA-229次级代谢产物研究

摘要

A new 4-phenyl-3,4-dihydroquinolone derivative,22-epi-aflaquinolone B(1) together with four related known derivatives(2～5) and four known quinazolinone alkaloids(6～9),were isolated and identified from the culture extract of Aspergillus versicolor MA-229,an endophytie fungus obtained from the fresh leaves of the marine mangrove plant Lumnitzera racemosa.The structures of these compounds were established by NMR and MS spectroscopic analysis,and the structure and absolute configuration of 1 were confirmed by the X-ray crystallographic experiment.Each of these compounds was evaluated for brine shrimp lethality and antimicrobial activity.Compound 1 exhibited antifungal activity against Gaeumannomyces graminis with MIC value of 32μtg/mL and also exhibited potent brine shrimp (Artemia salina) lethality with LD50 value of 1.73μ mol/L,which is comparable to that of positive control.Compound 6 exhibited antifungal activity against Fusarium graminearum with MIC values of 16μ g/mL.%从分离自红树林植物榄李新鲜叶片中的内生真菌杂色曲霉Aspergillus versicolor MA-229的发酵产物中分离得到新化合物1(22-epi-aflaquinolone B)和4个4-苯基-3,4-二氢喹啉酮类化合物(2～5)以及4个喹诺唑啉酮类化合物(6～9).通过核磁共振和质谱等技术对化合物的结构进行了鉴定,并且通过X-射线单晶衍射实验确定了化合物1的绝对构型.这些化合物均表现出不同程度的卤虫致死活性和抗菌活性,其中新化合物1有明显的卤虫致死活性(LD50值为1.73 μmol/L),与阳性对照活性相当.化合物1对农业病害菌小麦全蚀病菌(Gaeumannomyces graminis)也具有一定的抑制活性(MIC值为32μg/mL),化合物6对农业病害菌小麦赤霉病菌(Fusarium graminearum)有较好的抑制活性(MIC值为16μg/mL).