豨莶草内生抗感染细菌的分离鉴定及生长特性  

Species Identification and Growth Characteristics of Endophytic Anti-infective Bacteria from Herba siegesbeckiae

作　　者：陈少红[1] 赵朋超[1] 陈明钊[1] 李洛宜[1] 李悦[1] 贾靖靖 

机构地区：[1]河南科技大学医学技术与工程学院,洛阳471023

出　　处：《生物技术通报》2017年第2期137-142,共6页Biotechnology Bulletin

基　　金：河南省高等学校重点科研项目(15A180038);河南科技大学博士科研启动基金项目(4022/13480021);河南科技大学大学生科研训练计划项目(2015125);国家级大学生创新创业训练计划项目(201510464048)

摘　　要：豨莶草有多种药用价值,旨在从豨莶草果实中分离和筛选出高拮抗活性的内生细菌。采用了形态学观察、生理生化试验、16S r RNA序列比对、系统发育树分析以及OD600值、药敏试验和超滤等方法对该抗感染细菌C-5-1进行了相关生物学特性评价。结果显示,C-5-1为侧孢短芽孢杆菌(Brevibacillus laterosporus),对多种病原细菌均敏感,尤其是对铜绿假单胞菌;低p H和高Na Cl盐度环境中耐受性有限,在p H≤5.0或盐度≥15%时其生长受到了完全的抑制甚至是死亡,但在p H范围7.0-11.0和盐度范围0-5%下均能生长良好,说明该菌株为耐碱,但不耐酸和盐;筛选出了对菌株C-5-1高度敏感而对5种指示病原菌耐药的抗生素,即氨苄西林;C-5-1发酵上清液中存在着两种抗菌物质,且它们的相对分子质量均小于2 000。因此豨莶草有着优良微生物资源,可以成为开发抗感染细菌药物的重要资源。Herba siegesbeckiae has many healing values, and our aim is to isolate and screen highly active antagonistic endophytes from its fruits. The biological characteristics of anti-infective bacterium C-5-1 were determined by antagonistic experiment, morphological observation, physiological and biochemical tests, sequence alignment of 16S rRNA gene, analysis of phylogenetic tree, measuring OD600, drug sensitive tests, and ultra-filtration centrifugation. The results showed that the C-5-1 was identified as Bt＇evibacillus laterosporus and was sensitive to various pathogenic bacteria, especially Pseudomonas aeruginosa. The strain C-5-1 had limited tolerance to low pH and highly saline environments, i.e., inhibited completely or even died in pH ≤ 5 or more than 15% NaCl, but it grew well in pH ≥ 7 and 0-5% NaCl, suggesting that C-5-1 had good alkali resistance, but not resistant to acid and salt. Screening experiment revealed that the antibiotic ampicillin was highly sensitive to C-5-1, but resistant to 5 pathogenic bacteria. Fermentation supernatant of C-5-1 contained two antibacterial substances and relative molecular mass of both was less than 2 000. Conclusively, H. siegesbeckiae having excellent microbial resources will be a key resource for the development of anti-bacteria drugs.

关 键 词：豨莶草 侧孢短芽孢杆菌 氨苄西林 耐碱 超滤 

分 类 号：Q93[生物学—微生物学]