Abstract:Conjugated linoleic acid (CLA) has wide application potential in medicine, food, and health products, because of its anticancer, immune regulatory, anti-atherosclerosis, antiobesity, and antioxidant activities. Currently, commercial CLA is typically produced through alkali isomerisation using sunflower oil as raw material, generating a mixture of CLA with undesirable isomer by-products. Use of CLA for nutraceutical and medicinal purposes requires safe isomer-selective synthesis. Hence, CLA biosynthesis naturally attracted much attention because of its specificity and safety. The aim of the present study was to isolate and identify Lactobacillus strains from the fermented pickle brines, which can convert linoleic acid (LA) into CLA under aerobic conditions. Using serial dilutions and plate streaking in de Man Rogosa Sharpe (MRS) agar medium under aerobic conditions, 16 CLA-producing Lactobacillus strains were isolated, among which PC-3 exhibited the highest production of CLA. Based on analyses using SEM, API-50CHL, and 16S rRNA gene sequencing, PC-3 was identified as Lactobacillus plantarum. The 16S rDNA gene sequence（1460bp）was submitted to GenBank under the accession number JX270774.1.
