title: Hexanoyl-lysine as a deterioration marker for rice during storage.
abstract: N(ε)-(hexanoyl)lysine (HEL) is known to be an oxidative lipid-decomposition product, and a powerful marker indicating oxidative stress in animal tissue. We investigated whether HEL could be useful as a marker in rice seeds damaged by oxidative stress during storage, as well as animals. We could show an accumulation of HEL in rice stored at high temperature (40 °C). This result significantly corresponded with an accumulation of TBARS. Rice germination deteriorated with non-enzymatic lipid peroxidation during storage at high temperature for a few months. These results suggested that a deterioration of rice germination ability resulted from oxidative damage caused by lipid peroxidation during storage. Moreover, HEL could become a useful marker for oxidative stress induced by lipid peroxidation. In addition, the activities of antioxidant enzymes, catalase and superoxide dismutase, significantly decreased in the rice seeds during storage at 40 °C. The relationship between accumulation of HEL and increases in antioxidant enzymes activities must be further studied. But, these results suggest that HEL might be a useful marker of oxidative stress in rice as well as in animals.
authors.affiliation: Department of Applied Biological Chemistry, Meijo University, 1-501 Shiogamaguchi, Nagoya, 468-8502, Japan, minato@meijo-u.ac.jp.
authors.forename: Ken-ichiro
authors.initials: K
authors.lastname: Minato
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D000441:Hexanols / Q000737:chemistry*; D015227:Lipid Peroxidation; D008077:Lipoproteins, LDL / Q000737:chemistry / Q000378:metabolism; D008239:Lysine / Q000737:chemistry*; D012275:Oryza / Q000254:growth & development / Q000378:metabolism*; D018384:Oxidative Stress; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D000975:Antioxidants; D000441:Hexanols; D008077:Lipoproteins, LDL; C099252:oxidized low density lipoprotein; D002374:Catalase; D013482:Superoxide Dismutase; D008239:Lysine