番茄发酵液中乳酸杆菌的分离鉴定及对模拟胃肠液耐受性研究

Isolation and Identification of Lactobacillus in Tomato Fermentation Broth and Investigation of Its Tolerance to Simulated Gastrointestinal Environment

摘要:

为获得具有较好生长能力及胃肠耐受性的果蔬发酵剂，作者以自然发酵60 d的番茄液为对象，利用形态学及16S rDNA基因序列分析等方法，从中分离鉴定出3株乳酸杆菌（分别命名为L1、L2、L3），并研究其生长特性及对模拟胃肠环境的耐受能力。其中，L1和L3属于植物乳杆菌属（Lactiplantibacillus plantarum）；L2为乳杆菌属（Lactobacillus brevis），3株菌的最适生长pH值均为6.6，最适生长温度为30~38 ℃。耐受性研究发现，L1和L3具有更强的高温及高盐耐受性，L2具有更好的胆盐耐受性；3株乳酸杆菌尤其是L3对人工胃液环境具有良好的耐受能力，存活率均高于96%。在人工肠液环境下3株菌的存活率超过90%，尤其L1表现出更好的稳定性。结果表明，作者分离得到的3株乳杆菌均具有良好的生长特性和胃、肠耐受特性，本研究结果可为果蔬发酵剂的研制及其发酵制品的开发提供参考。

Abstract:

To obtain fruit and vegetable starters with good growth ability and gastrointestinal tolerance, 3 strains of Lactobacillus were isolated and identified (named L1, L2 and L3) from tomato fermentation broth that was naturally fermented for 60 days by morphology and 16S rDNA gene sequence analysis, and the growth characteristics and the tolerance to simulated gastrointestinal environment were studied. L1 and L3 belong to Lactobacillus plantarum, while L2 is Lactobacillus brevis. The optimum pH value for growth of the three strains was 6.6, and the optimum growth temperature was 30~38 ℃. The tolerance study results showed that L1 and L3 had stronger high temperature and high salt tolerance, while L2 has better bile salt tolerance. The 3 Lactobacillus had good tolerance to the artificial gastric fluid environment, especially L3, and the survival rates were over 96%. In the artificial intestinal fluid environment, the survival rates of the 3 Lactobacillus strains were over 90%, especially L1 showed better stability. The results showed that the 3 Lactobacillus strains had good growth characteristics and gastrointestinal tolerance, which can provide reference for the development of starter culture and fermented products of fruit and vegetable.