斜阳岛珊瑚礁区海泥可培养细菌分离鉴定及活性研究

【目的】研究广西斜阳岛珊瑚礁区海泥可培养细菌多样性及其代谢产物的生物活性。【方法】采用纯培养法和基于16SrRNA基因序列的系统发育分析细菌多样性,利用滤纸片琼脂扩散法和卤虫致死法研究其生物活性。【结果】从海泥中分离获得相关可培养细菌53株,这些菌株代表27个物种,其中20株菌属于厚壁菌门(74%),7株菌为变形菌门(26%)。活性研究发现,X-15(Erythrobacter citreus)的抑菌活性和生物毒活性都较强,具有开发新型食品防腐剂和抗肿瘤药物的潜力。【结论】广西斜阳岛海泥中的细菌多样性较为丰富。

Diversity and Bioactive of Cultivated Marine Bacteria Isolated from the Sea Bed Mud at Coral Reef Nearby the Xieyang Island

Objective] To investigate the diversity and bioactive of culturable bacteria isolated from the sea bed mud at coral reef nearby the Xieyang island.Methods] Cultivated marine bacteria were isolated from the sea bed mud at coral reef nearby the Xieyang island by using conventional culture-dependent method and their diversity was investigated by using phylogenetic analysis based on 16S rRNA gene sequence comparisons. Activities of the crude extract of isolated strains were tested through filter paper method and Brine shrimp lethality.Results] We isolated 53 bacterial strains from the sample on media (2216E, NA and ISP2) supplement with seawater. On the basis of morphological and biochemical characteristics, we selected 27 strains to perform a phyloenetic analysis based on 16S rRNA gene sequences. Results showed that 27 isolated strains represented 2 phyla. Activity results showed that the crude extract of 21 isolated strains, using four indicator bacteria as control, showed effective antibacterial activity, and 10 strains showed significant brine shrimp lethality. The antibacterial activity and toxicology activity of X-15 is better than that of the other strains, which shows it is great potential to be a new natural food preservatives and anti-cancer drug.Conclusion] Bacterial resources in coral reef nearby the Xieyang island was rich.