酸汤中高产酸细菌的分离筛选及其特性研究

Isolation and screening of high acid-producing bacteria in sour soup and its characterization

中文关键词:  酸汤  产酸细菌  分离筛选  抑菌特性

英文关键词:sour soup  acid-producing bacteria  isolation and screening  bacteriostatic properties

中文摘要:

      目的 分离筛选出酸汤中高产酸细菌对其进行鉴定，并研究其生物学特性。方法 从白酸汤和红酸汤中分离出的细菌，通过16S rDNA基因序列分析进行分子生物学鉴定，并研究其产酸特性、生理生化特性、耐酸碱和耐盐能力，同时用牛津杯法以抑菌圈为指标，探究其抑制致病菌性能。结果 筛选出4株高产酸乳酸菌和1株产酸醋杆菌，其中RS-5为甘草乳杆菌（Liquorilactobacillus nagelii），ST15-2和RS-8为布氏乳杆菌（Lentilactobacillus buchneri），ST20为发酵粘液乳杆菌（Limosilactobacillus fermentum），ST19为产液葡糖酸醋杆菌（Gluconacetobacter liquefaciens）；RS-8、ST15-2、ST20和RS-5具有较高的产酸能力，产总酸均超过(103.54±6.19) g/L，RS-8产总酸量达到(129.74±8.50) g/L，经高效液相色谱测定ST20、RS-5和ST15-2产乳酸较高，分别是10.21、9.76和7.11 mg/mL，RS-8和RS-5产柠檬酸较高，分别为4.87 mg/mL和3.93 mg/mL；RS-8、ST15-2和ST20具有较好的耐酸性、耐碱性和耐盐性；RS-5和ST20对大肠杆菌有显著抑制作用，ST15-2对金黄色葡萄球菌有显著抑制作用。结论 RS-8、ST15-2、ST20和RS-5高产酸且具有较好的耐酸碱和耐盐性能，有抑致病菌作用，具有一定工业化应用前景。

英文摘要:

      Objective Isolation and screening of high acid-producing bacteria in sour soup for their identification and study of their biological properties. Methods Bacteria isolated from white sour soup and red sour soup were identified molecularly by 16S rDNA gene sequence analysis, and their acid-producing characteristics, physiological and biochemical properties, acid and alkali resistance, and salt tolerance were investigated, while their inhibition of pathogenic bacteria performance was explored by using the Oxford cup method with the circle of inhibition as an indicator. Results Four strains of high acid-producing Lactobacillus and one acid-producing Acetobacter were screened, of which RS-5 was Liquorilactobacillus nagelii, ST15-2 and RS-8 were Lentilactobacillus buchneri, ST20 was Limosilactobacillus fermentum, and ST19 was Gluconacetobacter liquefaciens. RS-8, ST15-2, ST20, and RS-5 had high acid-producing capacity, and all of them produced more than (103.54±6.19) g/L of total acid. The total acid production of RS-8 reached (129.74±8.50) g/L. The lactic acid production of ST20, RS-5 and ST15-2 was higher as determined by high performance liquid chromatography (HPLC), which was 10.21, 9.76 and 7.11 mg/mL, respectively, and the citric acid production of RS-8 and RS-5 was higher, which was 4.87 mg/mL and 3.93 mg/mL, respectively; RS-8, ST15 -2 and ST20 had better acid, alkali and salt resistance; RS-5 and ST20 showed significant inhibition of E. coli, and ST15-2 showed significant inhibition of S. aureus. Conclusion RS-8, ST15-2, ST20 and RS-5 have high acid production and good acid and alkali resistance and salt resistance, and have the effect of inhibiting pathogenic bacteria, and have certain prospects for industrial application.