title: Conjugated linoleic acid conversion by six Lactobacillus plantarum strains cultured in MRS broth supplemented with sunflower oil and soymilk.
abstract: Six strains of Lactobacillus plantarum, isolated from traditional dairy products of minority nationalities, were evaluated for their ability to produce conjugated linoleic acid (CLA) from free linoleic acid in vitro. All the 6 strains were found to be capable of converting linoleic acid to CLA when using sunflower oil as substrate or during soymilk fermentation. The inhibitory effect of linoleic acid on the growth of the L. plantarum was also discussed. The production of CLA was increased with adding high concentration of substrate in sunflower oil and IMAU60042 produced the highest CLA both in sunflower oil and soymilk. The CLA was composted by 2 isomers: cis9, trans11-CLA and tran10, cis12-CLA, and cis9, tran s11-CLA covered the most part of the total CLA formed except for L. plantarum P8. The production of CLA was decreased during the storage of fermented soymilk. The CLA contents decreased significantly in the first week, also more quickly in 2 wk. Especially, tran10, cis12-CLA decreased more rapidly than cis9, tran11-CLA. No dramatic change was observed among other 8 fatty acids in soymilk. The proportion of unsaturated fatty acids varied after fermentation with different L. plantrum strains, but all decreased the during storage. The research on the ability of converting CLA of L. plantrum strains could be basis for the future research and development of fermented soymilk products.
  
  
  CONCLUSIONS
  Desirable probiotic traits, such as acid and bile tolerance, aggregation activity, and antibacterial activity, have been proved for the 6 Lactobacillus plantarum strains. The 6 L. plantarum strains might be used in the fermentation of soymilk to produce multifunctional probiotic soymilk products, especially the rich CLA contents.
authors.affiliation: The Key Laboratory of Dairy Biotechnology and Bioengineering, Education Ministry of PR China, Dept of Food Science and Engineering, Inner Mongolia Agricultural Univ, Huhhot 010018, PR China.
authors.forename: Haiping
authors.initials: H
authors.lastname: Li
authors.forename: Yong
authors.initials: Y
authors.lastname: Liu
authors.forename: Yan
authors.initials: Y
authors.lastname: Bao
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Liu
authors.forename: Heping
authors.initials: H
authors.lastname: Zhang
mesh_terms: D001628:Beverages / Q000032:analysis / Q000382:microbiology*; D002681:China; D003611:Dairy Products / Q000382:microbiology; D004032:Diet / Q000208:ethnology; D005285:Fermentation; D061353:Food Storage; D055951:Functional Food / Q000032:analysis / Q000382:microbiology; D048191:Lactiplantibacillus plantarum / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism*; D044243:Linoleic Acids, Conjugated / Q000737:chemistry / Q000378:metabolism*; D010938:Plant Oils / Q000378:metabolism*; D019936:Probiotics / Q000008:administration & dosage / Q000302:isolation & purification / Q000378:metabolism; D045730:Soy Foods / Q000032:analysis / Q000382:microbiology*; D013045:Species Specificity; D013237:Stereoisomerism; D000074242:Sunflower Oil; D013997:Time Factors
chemical_list: D044243:Linoleic Acids, Conjugated; D010938:Plant Oils; D000074242:Sunflower Oil; C503589:cis-9, trans-11-conjugated linoleic acid; C496197:trans-10,cis-12-conjugated linoleic acid