一株高产胞外多糖乳酸菌的鉴定及其特性研究  

Studies on Identification and Characterization of a High-yield Exopolysaccharides Lactic Acid Bacteria

作　　者：张国华[1] 张纬珍 梁武龙 王伟[1] 涂建[1] Zhang Guohua;Zhang Weizhen;Liang Wulong;Wang Wei;Tu Jian(School of Life Science,Shanxi University,Taiyuan 030006)

机构地区：[1]山西大学生命科学学院,太原030006

出　　处：《中国食品学报》2020年第12期229-238,共10页Journal of Chinese Institute Of Food Science and Technology

基　　金：国家自然科学基金青年科学基金项目(31601461);山西省自然科学基金青年科学基金项目(201701D221151)。

摘　　要：酸面团是一种面粉与水的混合物,包括酵母菌、乳酸菌与霉菌等微生物,由其发酵而成的馒头、包子等面制品深受人们的喜爱。为深入了解分离自传统酸面团中乳酸菌的基本特性,本文采用了一系列试验方法,如DNA提取与构建系统发育树、显微镜观察、红外光谱分析、生长量及生长曲线测定、pH值及产酸曲线测定、生化特性鉴定、抑菌及药敏性试验等。鉴定结果表明:该乳酸菌为旧金山乳杆菌,属革兰氏阳性菌,过氧化氢酶为阴性,细菌呈杆状。采用傅里叶变换红外光谱分析得到细菌的细胞成分包括脂肪酸、蛋白质、多糖等物质。旧金山乳杆菌的生物量为(24±1)g/L,繁殖代数为0.36,生长速率常数0.045,代时22.42 min,最低pH值为4.09±0.01,总酸度最高为(0.70±0.01)g/L。其能利用麦芽糖,蔗糖利用程度具有菌种差异性,对金黄色葡萄球菌、大肠杆菌、白色念珠球菌均有抑制作用,且测试的30种抗生素对旧金山乳杆菌的影响各有不同。一株高产胞外多糖的乳酸菌SXU-1001菌株为旧金山乳杆菌,是传统发酵酸面团中的优势乳酸菌,为开发酸面团中乳酸菌资源提供借鉴。Sourdough is a mixture of flour and water,including microorganisms such as yeast,lactic acid bacteria(LAB)and mold.The pasta products fermented by sourdough have been deeply loved by people in recent years.In order to understand the basic characteristics of LAB isolated from traditional sourdough,a series of test methods were used in this paper,such as DNA extraction and construction of phylogenetic tree,microscope observation,infrared spectroscopic analysis,growth and growth curve determination,pH value and acid production curve determination,biochemical properties identifcation,antibacterial and drug susceptibility test.The identification results indicated that the LAB was Lactobacillus sanfranciscensis,a gram-positive bacteria,catalase was negative,and the bacteria was rod-shaped.Fourier transform infrared spectroscopy was used to analyze the cell components of bacteria including fatty acids,proteins,polysaccharides and other substances.The biomass of L.sanfranciscensis was(24±1)g/L,the reproductive algebra was 0.36,the growth rate constant was 0.045,the generation time was 22.42 min,the lowest pH was 4.09±0.01,and the total acidity was(0.70±0.01)g/L.It can utilize maltose,and the degree of sucrose utilization has differences in bacterial species.It has inhibitory effects on Staphylococcus aureus,Escherichia coli and Candida albicans.And the 30 antibiotics tested have different effects on L.sanfranciscensis.A strain of high-yield exopolysaccharide LAB SXU-1001 was L.sanfranciscensis,which was the dominant LAB in traditional sourdough,and provided a reference for the development of LAB resources in sourdough.

关 键 词：酸面团 乳酸菌 胞外多糖 旧金山乳杆菌 

分 类 号：TS213.2[轻工技术与工程—粮食、油脂及植物蛋白工程]