从血散薯（Stephania dielsiana Y.C.Wu）中寻找活性内生真菌，为血散薯植物资源的保护及活性天然产物的开发提供依据，对其茎、叶中内生真菌进行分离鉴定，并研究其抗菌活性。结果表明，从血散薯茎、叶中共分离得到38株内生真菌，其中31株经形态学结合分子生物学的方法鉴定表明，其归为14个不同的属，包括链格孢属（Alternaria）、炭团菌属 (Hypoxylon)、枝孢属（Cladosporium）、茎点霉属（Phoma）、镰刀属(Fusarium)、Stagonosporopsis、Ascomycete、毛壳菌属（Chaetomium）、拟盘多毛孢属(Pestalotiopsis）、弯孢霉属（Curvularia）、短梗霉属(Aureobasidium)、Annulohypoxylon、小光壳属(Leptosphaerulina)、刺盘孢属（Colletotrichum）。其中，优势属为链格孢属和茎点霉属。基于前期对峙拮抗预试验结果，选取14株内生真菌进行发酵培养，并测定其对9种植物病原真菌和10种动物病原细菌的抗菌活性。结果表明，内生真菌发酵产物粗提物对供试病原菌具有不同程度的抑制作用。其中，7株内生真菌（叶-8、Y-66、YB-12、J-12、J-34、J-36、J-55）的粗提物对5株或5株以上供试植物病原真菌具有明显抗菌活性。叶-8、J-12分别对玉米大斑病菌、金橘砂皮病菌表现出最佳的抗菌活性，EC₅₀值分别为0.063 1、0.006 2 mg/mL；J-34对甘蓝黑斑病菌、甘蔗凤梨病菌表现出最佳的抗菌活性，EC₅₀值分别为0.018 1、0.004 2 mg/mL。10株内生真菌的粗提物对金黄色葡萄球菌均具有抑制作用，MIC值介于0.500～10.000 mg/mL，4株内生真菌的粗提物对大肠杆菌具有抗菌活性，MIC值介于0.156～4.000 mg/mL。上述结果表明，血散薯茎叶中存在丰富的内生真菌资源，且其次生代谢产物具有广谱抗菌活性。

 In this study，endophytic fungi were isolated and identified from the stems and leaves of Stephania dielsiana Y.C.Wu,and their antimicrobial activities were analyzed to provide a basis for the protection of Stephania dielsiana Y.C.Wu plants and the development of active natural products.The results showed that a total of 38 endophytic fungi were obtained from the stems and leaves of Stephania  dielsiana Y.C.Wu,31 of them were identified and classified into 14 genera based on the morphological and molecular identification,including Alternaria,Hypoxylon,Cladosporium,Phoma,Fusarium,Stagonosporopsis,Ascomycete,Chaetomium，Pestalotiopsis，Curvularia，Aureobasidium,Annulohypoxylon,Leptosphaerulina and Colletotrichum.Among them,Alternaria and Phoma were the dominant genera.14 endophytic fungi were selected based on the antagonism results in pre-experimental test,to determine the antimicrobial activity with their extracts from the fermented culture against 9 plant pathogenic fungi and 10 animal pathogenic bacteria.The results showed that the extracts of the endophytic fungi had inhibitory activity against tested pathogens to some extent.The extracts of 7 endophytic fungi (leaf-8,Y-66，YB-12， J-12，J-34，J-36 and J-55) displayed significant antifungal activity against 5 or more phytopathogenic fungi.Among them，leaf-8 and J-12 showed the best inhibitory activity against Exserohilum turcicum and Diaporthe citri with the EC₅₀ values at 0.063 1 mg/mL and 0.006 2 mg/mL,respectively.J-34 had the best antibacterial activity against Alternaria oleracea and Ceratocystis paradoxa with the EC₅₀ values at 0.018 1 mg/mL and 0.004 2 mg/mL,respectively.In addition,the extracts of 10 endophytic fungi exhibited inhibitory activity against Staphyloccocus aureus with the MIC values ranging at 0.500—10.000 mg/mL,and 4 of them had inhibitory activity against Escherichia coli with the MIC values ranging at 0.156—4.000 mg/mL.The results indicate that there are abundant endophytic fungi distributed in the stems and leaves of Stephania dielsiana Y.C.Wu,and their secondary metabolites possess broad-spectrum antimicrobial activity．