Preparation of a t,t Conjugated Linoleic Acid Methylester (CLA-Me) Isomers Mixture from Synthetic CLA by Methylation with BF₃/Methanol

Abstract

Mixtures of t,t conjugated linoleic acid methylester (t,t CLA-Me) isomers were prepared from synthetic CLA, consisting of 47.8% t10,c12 CLA; 45.5% c9,t11 CLA; 2.0% t,t CLA; and 4.7% others, by methylation with BF(3)/methanol (designated TT-TC/CT) in conjunction with purification at -68 degrees C for 24 h. The amount or composition of the TT-TC/CT was greatly affected by the concentration of BF(3) in methanol and the duration of methylation. The methylation of 50 mg of synthetic CLA for 30 min with 1 mL of 7.0% BF(3)/methanol produced a TT-TC/CT (21.54 mg) with the composition of 1.3% t12,t14; 5.9% t11,t13; 42.7% t10,t12; 44.0% t9,t11; 5.0% t8,t10; and 1.1% t 7,t9 CLA, whereas the methylation for 60 min with 14.0% BF(3)/methanol produced a TT-TC/CT (28.62 mg) with the composition of t,t CLA isomers different from that of TT-TC/CT by methylation for 30 min with 7.0% BF(3)/methanol. A large quantity of TT-TC/CT (14.15 g) with the composition similar to that of TT-TC/CT prepared from 50 mg of synthetic CLA was also prepared from 25 g of synthetic CLA. The purity of TT-TC/CT samples was greater than 98%. These results suggest that TT-TC/CT with a purity greater than 98% was easily prepared from synthetic CLA by BF(3)-catalyzed methylation, and the amount and composition of t,t CLA isomers of TT-TC/CT samples could be controlled by methylation conditions.

Growth Inhibition of Osteosarcoma Cell MG‐63 by a Mixture of trans,trans Conjugated Linoleic Acid Isomers: Possible Mechanistic Actions

“…The c 9, t 11 and t 10, c 12 CLA were prepared from synthetic CLA methyl ester (Kim and others 2000), and the t,t CLA was prepared from synthetic CLA (Kim and others 2003). The purity of CLA isomers was 99% t 10, c 12 CLA, 90.3% c 9, t 11 CLA, and 96% t,t CLA when analyzed by GC described subsequently.…”

“…The Ag + ‐HPLC analysis of the t,t CLA‐Me was carried out using a Young‐Lin M930 solvent delivery system (Anyang, Korea) with a UV detector (M720) operated at 233 nm and an operating system (Autochro‐win version 2.0) (Kim and others 2003). Two ChromSpher 5 Lipids analytical silver‐impregnated columns (4.6 mm i.d.…”

“…However, scientists have not paid attention to the biological effects of t,t CLA isomers ( t,t CLA) because of its availability. Previously, we synthesized a substantial amount of highly purified t,t CLA with a conjugated double bond at the following positions: 7,9; 8,10; 9,11; 10,12; 11,13; and 12,14 (Kim and others 2003). This will further clarify the underlying mechanistic action of t,t CLA.…”

High trans,trans Conjugated Linoleic Acid‐Rich Triacylglyceride Production by Photo‐Irradiation

“…Ju and Jung [15] showed that soy oil hydrogenation could be manipulated to produce 12 % trans,trans-CLA by adding sulfur with nickel as a catalyst; however, this process was accompanied with the formation of 19 % elaidic acid which is undesirable in food-grade oil [15]. trans,trans-CLA FAME were produced from synthetic CLA free fatty acids using BF 3methanol catalyzed methylation [16]; however, this method was unable to directly produce trans,trans-CLA TAG and the process is laborious and time consuming taking over 24 h to complete.…”

Preventive Effect of t,t-Conjugated Linoleic Acid on 12-O-Tetradecanoylphorbol-13-acetate-Induced Inhibition of Gap Junctional Intercellular Communication in Human Mammary Epithelial MCF-10A Cells

“…Since its discovery in fried ground beef, CLA has gained attention because of its important biofunctional activities, especially for its anti-carcinogenic and body fat reduction properties. In synthetic CLA, c 9, t 11-CLA and t 10, c 12-CLA isomers predominate and t 9, t 11-CLA and t 10, t 12-CLA are present as minor components . The anti-carcinogenic effects of different CLA isomers have been evaluated in many human cancer cell lines and animal models.…”