蒲公英内生真菌的分离、鉴定及抑菌活性研究

蒲公英为药食同源的一种传统植物,具有较好的抗菌消炎的功能,蒲公英提取物中含有多种具有抗菌活性的化合物,而植物内生真菌可产生与宿主植物相同或相似的代谢产物,可为抗菌化合物的开发利用开辟新途径。从蒲公英中分离获得蒲公英内生真菌,并选取金黄色葡萄球菌(Staphylococcus aureus)、大肠杆菌(Escherichia coli)、枯草芽孢杆菌(Bacillus subtilis)、肠炎沙门氏菌(Salmonella enteritidis)、铜绿假担孢菌(Pseudomonas aeruginosa)、白色念珠球菌(Candida sporogenes)等病原菌进行抑菌试验,对蒲公英内生真菌发酵产物进行了抑菌活性筛选,其中菌株PGY5具有较好的抑菌活性,对金黄色葡萄球菌的最小抑菌浓度(MIC)值为0.16 mg/m L,最小杀菌浓度(MBC)值为0.31 mg/m L。对大肠杆菌、枯草芽孢杆菌、肠炎沙门氏菌、铜绿假单孢菌和白色念珠菌也具有明显的抑菌效果,最小抑菌浓度(MIC)值分别为0.31 mg/m L,最小杀菌浓度(MBC)值为0.63 mg/m L。通过对菌株PGY5的ITS r-DNA序列进行比对分析,菌株PGY5为烟曲霉菌(Aspergillus fumigatus),与Aspergillus fumigatus JQ356539具有100%的相似性。通过LC-MS/MS检测在内生真菌PGY5乙酸乙酯层中发现了一种活性成分木犀草苷,其常存在于蒲公英叶中。

Isolation and Identification of Endophytic Fungi from Taraxacum mongolicum Hand-Mazz and Antibacterial Activity Study

Dandelion is a traditional plant homology of medicine and food. It has good antibacterial and anti-inflammatory function. The dandelion extracts contains compounds with multiple antibacterial activity, while the endophytic fungi can produce the same or similar metabolites with the host plant. It can open up a new way for the development and utilization of antibacterial compounds. This study isolated endophytic fungi from dandelion and screened Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Salmonella enteritidis, Pseudomonas aeruginosa and Candida sporogenes, etc. pathogenic bacteria to conduct anti-bacteria test and screen the bacteriostatistic activity of endophytic fungi tunning. Among them PGY5 had better bacteriostatic activity. The MIC and MBC values of Staphylococcus aureus were 0.16 mg/mL and 0.31 mg/mL, respctively. The MIC and MBC value of Escherichia coli, Bacillus subtilis, Salmonella enteritidis, Pseudomonas aeruginosa and Candida sporogenes were 0.31 mg/mL and 0.63 mg/mL, respectively. Endophyte PGY5 ITS r-DNA sequence was comparatively analyzed. PGY5 was identified as Aspergillus fumigatus and had 100% similarity with Aspergillus fumigatus JQ356539. An active ingredient galuteolin, which usually existed in Dandelion leaves, was found in ethyl acetate layer of endophytic fungi PGY5 by LC-MS/MS detection.