广西酸笋微生物多样性分析及其乳酸菌的特性研究

Analysis of Microbial Diversity of Guangxi Sour Bamboo Shoots and Study on Their Lactic Acid Bacteria Characteristics

为开发广西酸笋的纯种发酵工艺,需要筛选出具有较强亚硝酸盐降解能力以及高产GABA(γ-氨基丁酸)能力的乳酸菌。该研究首先对广西柳州不同厂家的酸笋进行微生物多样性分析,结果表明乳杆菌属(Lactobacillus sp.)为广西酸笋中的主要优势菌属。对筛选出的乳酸菌特性进行研究,结果显示菌株R9和R^(2)5降解亚硝酸盐的能力最强,降解率分别可达到(99.92±0.13)%和(99.03±0.66)%;菌株R^(2)2产生的GABA含量最高,为(71.77±3.35)μg/mL。对菌株L29、R9、R19、R^(2)2、R^(2)5进行耐受性研究,结果表明菌株R9、R19、R^(2)5对NaCl浓度≤7%、胆盐浓度≤0.7%、pH 3.5和pH 4有较强的耐受性,因此选择乳酸片球菌(Pediococcus acidilactici)R9、植物乳杆菌(Lactobacillus plantarum)R19和R^(2)5作为后续酸笋纯种发酵试验菌株。

In order to develop the pure breed fermentation process of Guangxi sour bamboo shoots,it is necessary to screen lactic acid bacteria with strong nitrite degradation ability and high GABA(γ-aminobutyric acid)production ability.In this study,the microbial diversity of sour bamboo shoots from different factories in Liuzhou,Guangxi is analyzed firstly,and the results show that Lactobacillus sp.is the main dominant genus of Guangxi sour bamboo shoots.The characteristics of the selected lactic acid bacteria are studied,the results show that strains R9 and R^(2)5 have the strongest ability to degrade nitrite,and the degradation rates could reach(99.92±0.13)%and(99.03±0.66)%respectively.Strain R^(2)2 produces the highest content of GABA,which is(71.77±3.35)μg/mL.The tolerance of strains L29,R9,R19,R^(2)2 and R^(2)5 is studied,and the results show that strains R9,R19 and R^(2)5 have strong torlerance to NaCl concentration≤7%,bile salt concentration≤0.7%,pH 3.5 and pH 4.Therefore,Pediococcus acidilactici R9,Lactobacillus plantarum R19 and R^(2)5 are selected as the subsequent pure breed fermentation experimental strains of sour bamboo shoots.