title: Method to produce 9(S)-hydroperoxides of linoleic and linolenic acids by maize lipoxygenase.
abstract: Seed from maize (corn) Zea mays provides a ready source of 9-lipoxygenase that oxidizes linoleic acid and linolenic acid into 9(S)-hydroperoxy-10(E),12(Z)-octadecadienoic acid and 9(S)-hydroperoxy-10(E),12(Z),15(Z)-octadecatrienoic acid, respectively. Corn seed has a very active hydroperoxide-decomposing enzyme, allene oxide synthase (AOS), which must be removed prior to oxidizing the fatty acid. A simple pH 4.5 treatment followed by centrifugation removes most of the AOS activity. Subsequent purification by ammonium sulfate fractional precipitation results in negligible improvement in 9-hydroperoxide formation. This facile alternative method of preparing 9-hydroperoxides has advantages over other commonly used plant lipoxygenases.
authors: Mycotoxin Research, NCAUR, ARS, USDA, Peoria, Illinois 61604, USA. gardnehw@mail.ncaur.usda.gov
authors: H W
authors: HW
authors: Gardner
authors: M J
authors: MJ
authors: Grove
mesh_terms: D002851:Chromatography, High Pressure Liquid; D006863:Hydrogen-Ion Concentration; D019787:Linoleic Acid / Q000737:chemistry / Q000378:metabolism*; D008054:Lipid Peroxides / Q000096:biosynthesis* / Q000737:chemistry; D008084:Lipoxygenase / Q000378:metabolism*; D012639:Seeds / Q000201:enzymology; D013237:Stereoisomerism; D003313:Zea mays / Q000201:enzymology*; D017962:alpha-Linolenic Acid / Q000737:chemistry / Q000378:metabolism*
chemical_list: D008054:Lipid Peroxides; D017962:alpha-Linolenic Acid; D019787:Linoleic Acid; D008084:Lipoxygenase