关键词: 共轭亚油酸, 植物乳酸杆菌, 筛选, 鉴定

Abstract: The aim of this study was to screen Lactobacillus planetarium strains which can produce conjugated linoleic acid (CLA) from naturally fermented Chinese sauerkraut juice by determining the CLA content of fermentation liquild with spectrophotometry,and identify the strain with the highest CLA-producing capacity by determining and analyzing its lactic acid-producing capacity; cell and colony morphology,and biochemistry and physiological characteristics. Eighteen CLA-producing bacterium strains were isolated with the yield varying from 0.094 mg per10 ml medium to 0.6213 mg per10 ml medium. One of the CLA-producing strains,X11,has the highest capacity to produce CLA. X11,and by being cultured in 10ml culture solution with 25μl linoleic acid for 24 h at 30 ℃,can produce 0.6213 mg CLA per 10 ml medium. The yield of X11 converting linoleic acid into CLA is 2.75%. Its configuration,lactic acid-producing,and biochemical and physiological characteristics lead to the identification of X11 as Lactobacillus plantarium.

Key words: conjugated linoleic acid, Lactobacillus plantarium strains, screening, identification