Optimization of Lipase‐Catalyzed Fractionation of Two Conjugated Linoleic Acid (CLA) Isomers

Abstract

The separation of two isomers of conjugated linoleic acid is highly significant since each exhibits different biochemical properties. The aim of this study was to investigate and optimize several factors affecting the esterification of L-menthol with the c9,t11-CLA isomer in an organic solvent-free system using lipase from Candida rugosa (Lipase AY-30). D-optimal design with 5 factors and 3 levels were employed to evaluate the effects of synthesis parameters; reaction time (8-24 h), temperature (30-50°C), enzyme content (2-20 U/ml), substrate molar ratio of conjugated linoleic acid oil to L-menthol (2:1-1:2) and pH (6-8) on esterification of c9,t11-CLA with L-menthol. Based on the analysis of the residual amount of c9,t11-CLA in the free fatty acid fraction after just one-step esterification, the optimum synthesis conditions were as follows: reaction time 23.12 h, temperature 32.65°C, enzyme amount 135.40 U, molar ratio of CLA oil to L-menthol at 1:1.7 and pH at 7.7; the lowest purity of c9,t11-CLA in free fatty acid fraction based on the total content of c9,t11 and t10,c12-CLA isomers was 8.6 %.

Optimization of solvent-free enzymatic esterification in eutectic substrate reaction mixture

“…The reaction optimization by a statistical design of experiments is a powerful method and has also been applied to CRL catalyzed esterification of (-)menthol [ 22 , 23 ]. For the optimization of the CRL catalyzed esterification in the (-)menthol:LA DES, experimental data from 20 runs was collected according to a CCD plan with coded and actual factor levels shown by Table 2 .…”

Linoleic Acid Triggered a Metabolomic Stress Condition in Three Species of Bifidobacteria Characterized by Different Conjugated Linoleic Acid-Producing Abilities

“…Assessment of Bifidobacterial Growth and CLA Production over Time. Seed cultures were inoculated at 1.5% in the mMRS or mMRS + LA broth and incubated for 0, 3,5,8,10,15,20,24,36,48, and 72 h under anaerobic conditions at 37 °C. Growth curves of all strains were constructed by measuring the optical density of the cultures at 600 nm (OD 600 ) (deducting the OD 600 value of the corresponding medium) at the end of each incubation time; these bacterial cultures were collected for FA or metabolite extraction.…”

“…4 Physiologically, c9, t11-CLA and t10, c12-CLA have been intensively reported as the two most active isomers of CLA. 5 Although CLA, a polyunsaturated fatty acid (PUFA), is naturally present in the fat and milk of ruminants, it is difficult for humans to consume enough quantities of this compound through natural foods for health promotion purposes. 6 As an important food-grade microorganism with an outstanding ability to convert LA into different CLA isomers, Bifidobacterium has long attracted the attention of food scientists.…”

“…Conjugated linoleic acid (CLA) is a collective group of 18-carbon conjugated dienoic acids with multiple physiological benefits for human health such as anti-inflammatory, anticarcinogenic, antioxidant, and antiobesity effects. − According to the latest expert consensus, CLA has been included in the category of prebiotics by the International Scientific Association for Probiotics and Prebiotics . Physiologically, c 9, t 11-CLA and t 10, c 12-CLA have been intensively reported as the two most active isomers of CLA . Although CLA, a polyunsaturated fatty acid (PUFA), is naturally present in the fat and milk of ruminants, it is difficult for humans to consume enough quantities of this compound through natural foods for health promotion purposes …”

Comparison and optimization of conjugated linoleic acid production by Lactobacillus plantarum and Lactobacillus plantarum subsp. plantarum

“…Lactobacillus plantarum is one of the strains of Lactic acid bacteria capable to produce nutritious and valuable products such as Conjugated Linoleic Acid (CLA). CLA is a natural derivative of the essential fatty acid (linoleic acid) and has received increasing attention in recent years due to its health e ects potential [1], such as having anticarcinogenic activity [2][3][4], enhancing the immune system, or decreasing body fat content [5]. CLA is not a single substance but actually a mixed group of positional and geometrical isomers of linoleic The use of biological reactions to produce CLA is recommended.…”