蚌花内生真菌类群分布及抗菌、抗肿瘤活性的初筛

The distribution, antimicrobial and antitumor activities of fungal endophytes from Rhoeo discolor(L. Hér) Hance

目的分析蚌花内生真菌的类群分布,并筛选具有抗菌和抗肿瘤活性的内生真菌菌株。方法通过菌落特佂、显微孢子观察及基于ITS序列分析的分子鉴定方法分析蚌花各部位内生真菌的类群组成,采用酶标仪法和MTT法对35株代表性内生真菌发酵液的抗菌活性和抗肿瘤活性进行筛选。结果从蚌花的叶、花瓣、花蕊共分离到310株内生真菌,叶中以球座菌属(53.1%)、刺盘孢属(29.2%)为主要类群,花瓣的主要类群为刺盘孢属(39.1%)和曲霉属(24.5%),花蕊的主要类群为青霉属(47.1%)和曲霉属(41.4%)。35株代表性内生真菌发酵液的抗菌、抗肿瘤活性分析结果显示,对金黄色葡萄球菌、枯草芽孢杆菌、大肠埃希菌、痢疾杆菌、伤寒沙门菌和白色假丝酵母菌具有抑制作用的活性菌株比例分别为80.0%、57.1%、40.0%、45.71%、28.57%和45.71%,对肝癌细胞BEL-7402和乳腺癌细胞MCF-7具有抑制作用的活性菌株分别占85.71%和68.57%。结论蚌花内生真菌的类群分布具有一定的组织特异性;蚌花内生真菌的代谢产物具有较高比率的抗菌和抗肿瘤活性,有望成为筛选新型抗菌和抗肿瘤药物的重要资源库。

Objective To investigate the distribution of communities,antimicrobial and antitumor activities of the fungal endophytes of Rhoeo discolor（ L. Hér） Hance. Methods The endophytic fungi form Rhoeo discolor（ L. Hér） Hance were identified by morphological traits of the colony and spores,and fungal ITS region sequence analysis. The antimicrobial and antitumor activities tests of fungal endophytes were used by the microplate reader rapid determining method and MTT method, respectively. Results 310 strains endophytic fungi were isolated from the leave,petals and stamens of R. discolor（ L. Hér） Hance. The taxa of preponderant fungal endophyte communities in lamina were Guignardia（ 53. 1%） and Colletotrichum（ 29.2%）,in petals were Colletotrichum（ 39. 1%） and Aspergillus（ 24. 5%）, in stamens were Penicillium（ 47.1%） and Aspergillus（ 41. 4%）. The results of the antimicrobial and antitumor assays for 35 strains representative fungal endophytes showed that the endophytic fungi had inhibitory activity to Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Shigella dysenteriae, Salmonella typhimurium, and Candida albicans,were accounted for 80. 0%, 57. 1%, 40. 0%, 45. 7%, 28. 6%, and 45. 7%, respectively. The antitumor activities to human liver cancer cells BEL-7402 and human breast cancer cells MCF-7 were accounted for 85. 71% and 68. 57%, respectively. Conclusion There were abundant endophytic fungi in R.discolor（ L. Hér） Hance, the taxa distributions of which showed certain organization specificity. The metabolites of endophytic fungi from R. discolor（ L. Hér） Hance showed significant antimicrobial and antitumor activity,which could be expected as the important resource for screening new antibacterial and antitumor drugs.