一株中度嗜盐细菌whb45的鉴定及其抗菌与抗肿瘤活性筛选

Identification of a Moderately Halophilic Bacterium whb45 and Screening of Its Antimicrobial and Antitumor Activity

摘要:

从盐场中分离鉴定中度嗜盐细菌并对其潜在的抗菌和抗肿瘤活性进行评价。从山东威海的鹿道口盐场分离嗜盐细菌, 对菌株whb45进行形态学和生理生化特性研究, 测定其16S rRNA序列并通过同源性比对进行系统发育分析, 采用抗菌和细胞毒模型进行活性筛选。试验结果表明, 菌株whb45为中度嗜盐细菌, whb45与Halobacillus trueperi在形态和生理生化特征方面最接近, 16S rRNA序列相似性为99%。whb45的粗提物对多种细菌、真菌和肿瘤细胞的生长都具有较强的抑制作用, 可以作为发现生物活性物质的潜在的新来源。

关键词:中度嗜盐细菌, 鉴定, 喜盐芽孢杆菌属, 抗菌活性, 抗肿瘤活性

Abstract:

The aim of this study was to isolate and identify moderately halophilic bacteria from solar saltern and to investigate their potential antimicrobial and antitumor activities. Halophilic bacteria were isolated from Ludaokou Solar Saltern in Weihai of Shandong Province. The identification of the strain whb45 was determined by their morphological characteristics, physiological and biochemical tests and phylogenetic analysis based on 16S rRNA sequence comparison. The antimicrobial activity and cytotoxic activity were screened. Our results showed that the strain whb45 was belonged to moderately halophilic bacterium. Phy-logenetic analysis showed the strain whb45 had a 99% homology with Halobacillus trueperi. The crude ex-tract from whb45 showed stronger antimicrobial activities which could inhibit the growth of several bacteria and fungi. MTT analysis revealed that the strain possessed potent anticancer activity with the stronger in-hibitory effect on several human cancer cells. Our results suggested that the moderately halophilic bacterium whb45 may be developed as a potential new source for the discovery of novel bioactive substances.

Key words:Moderately halophilic bacteria, Identification, Halobacillus, Antimicrobial activity, Antitumor activity