Research progress on conjugated linoleic acid bio-conversion in Bifidobacterium.

Conjugated linoleic acid (CLA), a group of 18 carbon conjugated dienoic acids, has been considered a promising food supplement owing to its various physiological benefits to human health. Owing to a high isomer selectivity of the product and a simple isolation and purification process, microbial CLA has become a research hotspot. Many food-grade bacteria such as Lactobacillus and Bifidobacterium have been reported to possess CLA-production ability. Particularly, Bifidobacterium has high bio-conversion rate and enhanced CLA production, and is one of the best and most promising CLA producers among microorganisms. Consequently, this article aimed to review the current knowledge about Bifidobacterium CLA producers, the complex factors regulating CLA production in Bifidobacterium, the role of CLA production in Bifidobacterium, and the potential mechanism underlying Bifidobacterium CLA production. In summary, the above information offers novel insights into the production of food-grade CLA as well as the rational design of health-promoting fermented foods or synbiotics.