类开菲尔粒的发酵特性及强产酸乳酸菌的分离鉴定  

Characteristics of Kefir-like Grains and Isolation of Lactobacilli with High Yield of Acid

作　　者：张晓琳[1,2,3] 王炜[2,4] 张广敏[1,2] 常玮[2] 孔健[3] 

机构地区：[1]石河子大学农业技术重点实验室,新疆石河子832003 [2]新疆农科院微生物所,乌鲁木齐830091 [3]山东大学微生物技术国家重点实验室,济南250100 [4]新疆特殊环境微生物工程技术研究中心,乌鲁木齐830091

出　　处：《新疆农业科学》2009年第4期856-860,共5页Xinjiang Agricultural Sciences

基　　金：国家科技基础条件平台建设项目“农业微生物菌种资源标准化整理整合及共享试点”子课题“极端环境微生物菌种资源整理、整合”(2005DKA21201-12)

摘　　要：研究了1株来自青藏高原的类开菲尔粒的发酵特性。结果表明,以3%(W/V)接种量将类开菲尔粒接种到灭菌的牛奶中,在37℃下培养24 h可使发酵乳的pH值降低至4,游离氨基酸含量在发酵初期略有下降,随着培养时间的延长,游离氨基酸逐渐增加。利用MRS和GM17培养基平板,从类开菲尔粒中分离到23株乳酸菌,其中,菌株ZX1-3、ZX2-2和ZX5-5产酸性能较强,使发酵乳的pH值分别降低到3.97、4.11和4.04。经生理生化检测及16 S rDNA序列比对,上述3株菌均被鉴定为植物乳杆菌。测定其耐酸性,菌株ZX1-3和ZX5-5具有一定的耐酸性,预示着菌株在乳制品发酵及饲料青贮中有潜在的开发前景。The fermentation characteristics of a kefir - like grain from Qing - Tibet Plateau were studied in this paper. The results showed that the pH value of fermented milk was dropped to about 4 after incubation for 24 h. The concentration of free amino acids in the fermented milk was decreased in the initial stage of fermentation, and then was increased with the prolonging of the cultural time. Twenty three strains were isolated from the kefir-like grain on the MRS or GM17 plates and production of organic acid was assessed during 12 h incubation at 37 ℃. Three isolates of them were obtained with high level of organic acid. The pH value of their milk cultures were dropped to 3.97,4.11 and 4.04 , respectively. They were identified as Lactobacillus phmtarum by physiological and biochemical tests combining with the 16S rDNA sequence analysis. Determination of the acid - resistance showed that the strains ZX1 - 3 and ZX5 - 5 were able to survive in the pH 2 condition, suggesting their potential application in dairy fermentation and silage fermentation.

关 键 词：类开菲尔粒 游离氨基酸 乳酸菌 植物乳杆菌 

分 类 号：S188[农业科学—农业基础科学]