番茄自然发酵液中酵母菌的分离鉴定及其特性研究

为研究番茄自然发酵液中的酵母菌及其特性，对发酵30 d番茄发酵液中的酵母菌分离纯化，通过菌落形态、镜检特征和26S rDNA序列对分离的菌株进行鉴定，并对该菌的生长特性和耐受性进行评价。结果表明，从番茄发酵液中分离出TY-1、TY-2和TY-3 3株酵母菌均为毕赤酵母属（Pichia）中的库德毕赤酵母种（P.kudriavzevii）；其中TY-1和TY-2亲缘关系较近，且与P.kudriavzevii strain SLDY-035菌株的同源性为99%，故选取TY-1进行后续实验；TY-3与P.kudriavzevii small subunit ribosomal菌株的同源性为100%。TY-1和TY-3的最佳生长温度为29℃、pH5.5，对10%~30%葡萄糖和6%~9%酒精具有一定的耐受能力。结果表明，从番茄发酵液中分离得到的酵母菌株具有良好的生长性能，可为果蔬发酵剂的开发奠定基础。

Isolation and Identification of Yeasts from Tomato Natural Fermentation Broth and Its Characteristics Analysis

To study the yeast and its characteristics in tomato fermentation broth,the gradient dilution method was used to isolate and purify the yeast in the tomato fermentation broth for 30 days of natural fermentation.The strain was identified by colony morphology,microscopic characteristics and 26S rDNA sequence analysis,the growth characteristics and tolerance of the identified strain were analyzed.The results showed that three strains of yeast TY-1,TY-2 and TY-3 from tomato fermentation broth were all Pichia kudriavzevii.Among which TY-1 and TY-2 were identified as the same strain as P.kudriavzevii strain SLDY-035,their homology was 99%.The homology between TY-3 and P.kudriavzevii small subunit ribosomal was 100%.The optimum growth temperature and pH of TY-1 and TY-3 was 29℃and 5.5,respectively,they were tolerant to 10%~30%glucose and 6%~9%alcohol.The yeast strains isolated from tomato fermentation broth had good growth performance,which could lay a foundation for the development of fruit and vegetable fermentation agents.