a State Key Laboratory of Food Science and Technology, School of Food Science and Technology , Jiangnan University , Wuxi , Jiangsu , P. R China.
b International Joint Research Laboratory for Probiotics at Jiangnan University , Wuxi , Jiangsu , P. R China.
Bioengineered. 2017 May 4;8(3):232-238. doi: 10.1080/21655979.2016.1222996. Epub 2016 Sep 22.
Conjugated linolenic acid (CLNA) is a family of isomers of linolenic acid with a number of health-associated benefits, which has been attracting great interest. Microbial CLNA producers are potentially an alternative source of CLNA for human nutrition. In present study, 16 neonate feces were collected and used for Bifidobacteria isolation, from which 25 bifidobacteria isolates were obtained. The bifidobacteria isolates were identified using 16s rDNA sequencing as Bifidobacterium adolescentis, B. breve, B. longum and B. pseudocatenulatum. These isolates were further investigated for their ability to produce CLNA using linolenic acid as substrate via GC-MS. The results showed most of the isolates could convert free linolenic acid into c9,t11,c15-CLNA and t9,t11,c15-CLNA at different levels. B. pseudocatenulatum was the most effective CLNA producer, which converted 86.91% of linolenic acid to c9,t11,c15-CLNA and 3.59% of to t9,t11,c15-CLNA isomer and the isolate exhibited to accumulate CLNA during 72 h culturing in which most CLNA isomers were in the supernatant fluid. The results indicated that utilization of this isolate for CLNA production will eliminate the purification process.
共轭亚油酸（CLNA）是亚油酸的一组异构体，具有多种与健康相关的益处，因此引起了极大的关注。微生物 CLNA 生产者是人类营养中 CLNA 的潜在替代来源。在本研究中，收集了 16 份新生儿粪便用于双歧杆菌的分离，从中获得了 25 株双歧杆菌分离株。通过 16s rDNA 测序将双歧杆菌分离株鉴定为青春双歧杆菌、短双歧杆菌、长双歧杆菌和假链状双歧杆菌。进一步通过 GC-MS 研究了这些分离株利用亚油酸作为底物生产 CLNA 的能力。结果表明，大多数分离株能够将游离亚油酸转化为不同水平的 c9,t11,c15-CLNA 和 t9,t11,c15-CLNA。假链状双歧杆菌是最有效的 CLNA 产生菌，能够将 86.91%的亚油酸转化为 c9,t11,c15-CLNA，3.59%的 t9,t11,c15-CLNA 异构体，并且该分离株在 72 h 的培养过程中积累 CLNA，其中大多数 CLNA 异构体存在于上清液中。结果表明，利用该分离株生产 CLNA 将消除纯化过程。
