title: Formation of 6,13-dihydroxyoctadecatrienoic acid isomers from gamma-linolenic acid.
abstract: Incubation of gamma-linolenic acid with soybean lipoxygenase initially at pH 9.3 and subsequently at pH 7.9 gave rise to the conjugated triene dioxygenation product (lambda max = 267 nm, greater than 50% yield), which was reduced to form 9-cis isomer of 6,13-dihydroxyoctadecatrienoic acid (6,13-diHOT) accompanied by minor isomers. Meanwhile, hemoglobin converted 13-hydroperoxyoctadecatrienoic acid into two major 9-trans isomers of 6,13-diHOT and two 9-cis isomers as minor products. The four isomers of 6,13-diHOT methyl ester were separated from each other on SP-HPLC, and characterized by chromatographic, spectrometric and cis----trans isomerization analyses.
authors.affiliation: Department of Food & Nutrition, Chungnam National University, Daejeon, Korea.
authors.forename: M R
authors.initials: MR
authors.lastname: Kim
authors.forename: D E
authors.initials: DE
authors.lastname: Sok
mesh_terms: D002851:Chromatography, High Pressure Liquid; D007536:Isomerism; D008042:Linolenic Acids / Q000096:biosynthesis* / Q000302:isolation & purification / Q000378:metabolism*; D008084:Lipoxygenase / Q000378:metabolism*; D013058:Mass Spectrometry; D010944:Plants / Q000201:enzymology*; D013025:Glycine max / Q000201:enzymology; D013056:Spectrophotometry, Ultraviolet; D017965:gamma-Linolenic Acid
chemical_list: D008042:Linolenic Acids; C059044:6,13-dihydroxyoctadecatrienoic acid; D017965:gamma-Linolenic Acid; D008084:Lipoxygenase