邓 丽^*，孙 冉，姚蒋庞，谢毓丹

（贵州大学生命科学学院/农业生物工程研究院，山地植物资源保护与保护种质创新教育部重点实验室，山地生态与农业生物工程协同创新中心，贵州贵阳 550025）

摘要：本研究旨在探究贝莱斯芽孢杆菌（Bacillus velezensis）粗提物对食源性病原菌－金黄色葡萄球菌（Staphylococcus aureus，PJ-1）的抑菌机制。以贝莱斯芽孢杆菌为原材料，用不同极性的有机溶剂萃取得到不同组分，采用牛津杯法筛选对PJ-1有良好抑菌活性的组分，运用气相色谱-质谱（GC-MS）对其进行成分分析；并通过半抑制浓度（EC₅₀）、生长曲线、细胞存活率、菌液的电导率、核酸蛋白的泄漏程度、β-半乳糖苷酶的变化、胞外可溶性多糖含量和三羧酸循环关键酶琥珀酸脱氢酶（SDH）和苹果酸脱氢酶（NAD-MDH）的活性对其进行抑菌机制研究。贝莱斯芽孢杆菌乙酸乙酯粗提物（AE）对PJ-1有良好的抑制作用，GC-MS检测出24种化合物，鉴定出17种，其中主要物质为10-羟基-2-癸烯酸（41.993%）、1，4-二氮杂2，5-二氧杂-3-异丁基双环［4.3.0］壬烷（8.798%）、3-甲基二氧哌嗪（8.257%）、L-亮氨酸（5.829%）等；AE对PJ-1的EC₅₀为21.310 2 μg/mL；AE可破坏细胞膜外膜和内膜的完整性，抑制多糖的合成，降低细胞存活率、SDH和NAD-MDH的活性。本研究为AE用于抑制食源性金黄色葡萄球提供了一定的理论基础。

关键词：贝莱斯芽孢杆菌；金黄色葡萄球菌；抑菌机制

中图分类号：TS201.3   文献标识码：A   文章编号：1674-506X（2021）03-0001-0009

Antibacterial Mechanism of Crude Extract of Bacillus velezensis Against Staphylococcus aureus

DENG Li^*, SUN Ran, YAO Jiang-pang, XIE Yu-dan

（Key Laboratory of Plant Resource Conservation and Germplasm Innovation in Mountainous Region （Ministry of Education）,

Collaborative Innovation Center for Mountain Ecology & Agro-Bioengineering, College of Life Sciences/Institute

of Agro-bioengineering, Guizhou University, Guiyang Guizhou 550025, China）

Abstract：The purpose of this experiment is to explore the antibacterial mechanism of the fermentation product of Bacillus velezensis on the food-borne pathogen-Staphylococcu saureus PJ-1. Methods: Using B.velezensis as raw material, different components were extracted with organic solvents of different polarities. The Oxford cup method was used to screen the components with good antibacterial activity against PJ-1, which performed by Gas chromatography-mass spectrometry (GC-MS). And through the semi-inhibitory concentration (EC₅₀), growth curve, the conductivity of the bacterial solution, the degree of leakage of nucleic acid protein，the change of β-galactosidase, cell survival rate, extracellular soluble polysaccharide content and the activity of the key enzymes of the tricarboxylic acid cycle, succinate dehydrogenase (SDH) and malate dehydrogenase (NAD-MDH) were studied. It showed that the crude extract of the ethyl acetate extract (AE) of B.velezensis had a good inhibitory effect on PJ-1, GC-MS detected 24 compounds and identified 17 compounds, among which the main substances were 10-hydroxy-2-decenoic acid (41.993%), 1, 4-diaza 2, 5-dioxa-3-iso Butylbicyclo [4.3.0] nonane (8.798%), 3-methyldioxypiperazine (8.257%), L-leucine (5.829%), etc.; The EC₅₀ of AE against PJ-1 is 21.310 2 μg/mL; AE can destroy the integrity of the outer and inner membranes of the cell membrane, inhibit the synthesis of polysaccharides, and reduce cell survival rate, SDH and NAD-MDH activities. Therefore, This study provides a theoretical basis for the use of AE to inhibit food-borne pathogen S.saureus.

Keywords：Bacillus velezensis; Staphylococcus aureus; bacteriostatic mechanism

doi：10.3969/j.issn.1674-506X.2021.03-001

收稿日期：2021-03-11

作者简介：邓丽（1994-），女，硕士研究生。研究方向：食品微生物学。

*通信作者

引用格式:邓丽,孙冉,姚蒋庞,等.贝莱斯芽孢杆菌粗提物对金黄色葡萄球菌的抑菌机制[J].食品与发酵科技,2021,57(3):1-9.