两株海洋微生物抗肿瘤代谢产物的筛选及其菌种鉴定

Screening of Antitumor Metabolites From Two Marine Microorganisms and Their Strain Identification

中文关键词: 海洋微生物  菌种鉴定  代谢产物  抗肿瘤活性

英文关键词: Marine microorganism  Strain identification  Fermented product  Antitumor activity

中文摘要:

      对5株海洋微生物进行发酵培养，发酵液离心后，收集上清液，采用饱和正丁醇萃取制备海洋微生物的代谢产物，采用MTT活性跟踪法，以BEL-7402、RKO、A549、U251和MCF-7等细胞系为模型，对代谢产物进行抗肿瘤活性的筛选。结果显示，菌株S-1和N16代谢产物的活性组分具有较好的抗肿瘤活性：菌株S-1对MCF-7、U251和BEL-7402三种肿瘤细胞的IC50值分别为44、102和82 μg/ml；菌株N16对MCF-7和BEL-7402两种肿瘤细胞的IC50值分别为84、133 μg/ml。对菌株S-1和N16进行了16S rRNA序列分析、生理生化特征鉴定，结果显示，菌株S-1为短芽孢杆菌属(Brevibacillus sp.)，N16为芽孢杆菌属(Bacillus sp.)。通过显微镜观察了菌株Brevibacillus sp. S-1和Bacillus sp. N16代谢产物的活性组分对BEL-7402细胞形态的影响，表明两株菌的活性组分可以改变肝癌细胞BEL-7402的细胞形态，抑制细胞增殖。该研究为新型抗肿瘤先导化合物的发现提供了新的海洋微生物种质资源。

英文摘要:

      Marine microorganisms are the important resources in the natural products with biological activity. Finding antitumor drugs and compounds from germplasm resources has become a hot topic. The current study investigated the biological role of the fermented products of marine bacteria isolated from marine strains in several cancer cell lines. Five marine strains were fermented, and the supernatant was collected after centrifugation as total products that were fractionated with n-butyl alcohol. The pooled organic layer was evaporated using a rotary evaporator under reduced pressure, and the peptide pellet was dissolved in phosphate buffer for further usages. Antitumor metabolites of five marine microorganisms were screened by MTT method in several cancer cell lines. The result showed that the fermented products of strain S-1 and N16 inhibited cancer cell proliferation. Specifically, fermented product from strain S-1 attenuated MCF-7, U251 and BEL-7402 cell proliferation and the IC50 were 44 μg/ml, 82 μg/ml and 102 μg/ml, respectively. Moreover, fermented product from strain N16 inhibited MCF-7 and BEL-7402 cell proliferation and their IC50 was 84 μg/ml and 133 μg/ml, respectively. The fermented products of S-1 and N16 induced the morphological change of the BEL-7402 cells. According to their 16S rRNA sequences and physiological biochemical properties，strains S-1 and N16 were identified as Brevibacillus sp. and Bacillus sp., respectively. The further research is to find new antitumor compounds from the fermented products of marine bacteria Brevibacillus sp. S-1 and Bacillus sp. N16. This study supports that the germplasm resources of marine microorganisms may be a novel resource for the discovery of novel anti-tumor compounds.