四种植物内生真菌的分离及其抗肿瘤活性的筛选

Endophytic Fungi from Four Plant Species: Their Isolation and Antitumor Activity

从银杏、合欢、臭椿和苦楝的树皮中分离到61株内生真菌。MTT法检测显示在45.9%的菌株发酵液粗提物在200μg/mL时对人食道癌细胞EC109的生长抑制率大于50%。其中6株内生真菌(YX5,YX17,YX36,KL1,CC1,CC5)在50μg/mL时仍具有较高的细胞毒活性,且活性成分主要分布在菌株的发酵液中。合欢内生真菌中的活性菌株比例最小,在50μg/mL时均未显示任何对EC109细胞的抑制作用。银杏中的高活性菌株比例最大,占银杏内生真菌的15.8%。银杏分离菌株YX5的活性最为突出,其发酵液粗提物对3种肿瘤细胞EC109,HONE1和HeLa的抑制率IC50分别是18.3μg/mL、3.6μg/mL和6.5μg/mL。研究结果表明,作为抗肿瘤药物的潜在来源银杏内生真菌值得关注。

We isolated 61 endophyte isolates from the bark of 4 plants, Ginkgo biloba L, Albizzia？julibrissin Durazz, Ailanthus sltissima （Mill） Swingle and Melia azedarach L. At the test concentration of 200 μg/mL, higher than 50% of antitumor activities were demonstrated with crude extracts from 45.9% of fungal culture in MTT assay. Six isolates, YX5, YX17, YX36, KL1, CC1 and CC5, still showed higher cytotoxicity at 50 μg/mL. No isolates from A.？julibrissin had inhibitory effect towards EC109 at the test concentration of 50 μg/mL; while about 15.8% of isolates from G. biloba were active. IC50 of the extract from the most active isolate YX5 against EC109, HONE1 and HeLa were 18.3 μg/mL, 3.6 μg/mL and 6.5 μg/mL, respectively. Our results indicate that endophytes from G. biloba could be regarded as a potent source of antitumor drugs.