Preparation and fractionation of conjugated trienes from alpha-linolenic acid and their growth-inhibitory effects on human tumor cells and fibroblasts.
Conjugated alpha-linolenic acid (CLnA) was prepared from alpha-linolenic acid (9,12,15-18:3n-3, LnA) by alkaline treatment; we fractionated CLnA into three peaks by reversed-phase column-HPLC as evidenced by monitoring absorbance at 205, 235, and 268 nm. Peak I was a conjugated dienoic FA derived from LnA, whereas Peaks II and III were conjugated trienoic LnA. Proton NMR analysis showed that Peak III consisted of the all-trans isomer. The methylated Peak III was further divided into five peaks (Peaks IV-VIII) by silver ion column-HPLC. Peak V, a major constituent in the Peak III fraction, was identified as conjugated 10t,12t,14t-LnA by GC-EIMS and 1H NMR analysis. Peaks III and V, which consisted of conjugated all-trans trienoic LnA, had stronger growth-inhibitory effects on human tumor cell lines than the other collected peaks and strongly induced lipid peroxidation as compared with Peaks I, II, and LnA. We propose that conjugated all-trans trienoic FA have the strongest growth-inhibitory effect among the conjugated trienoic acids and conjugated dienoic acids produced by alkaline treatment of alpha-LnA, and that this effect is mediated by lipid peroxidation.
Igarashi
Miki
M
Laboratory of Food & Biodynamic Chemistry, Graduate School of Agricultural Science, Tohoku University, Sendai 981-8555, Japan.
Miyazawa
Teruo
T
D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D005231:Fatty Acids, Unsaturated / Q000138:chemical synthesis* / Q000302:isolation & purification / Q000494:pharmacology*; D006801:Humans; D044243:Linoleic Acids, Conjugated / Q000138:chemical synthesis / Q000302:isolation & purification / Q000494:pharmacology; D015227:Lipid Peroxidation; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D013329:Structure-Activity Relationship; D017962:alpha-Linolenic Acid / Q000737:chemistry
D005231:Fatty Acids, Unsaturated; D044243:Linoleic Acids, Conjugated; D017962:alpha-Linolenic Acid