title: Antioxidant activity and inhibition of lipid peroxidation in germinating seeds of transgenic soybean expressing OsHGGT.
abstract: Tocochromanols are potent lipid-soluble antioxidants and essential nutrients for human health. Genetic engineering techniques were used to develop soybeans with enhanced vitamin E levels, including tocotrienols, which are not found in soybean. The gene encoding rice homogentisate geranylgeranyl transferase (HGGT) was overexpressed in soybeans using seed-specific and constitutive promoters. The association between abundance of vitamin E isomers and antioxidant activity was investigated during seed germination. With the exception of β-tocotrienol, all vitamin E isomers were detected in germinating seeds expressing OsHGGT. The antioxidant properties of germinating seed extracts were determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radicals and lipid peroxidation (TBARS). Compared with intact wild-type seeds, transgenic seeds showed increases in radical scavenging of 5.4-17 and 23.2-35.3% in the DPPH and ABTS assays, respectively. Furthermore, the lipid peroxidation levels were 2.0-4.5-fold lower in germinating seeds from transgenic lines than in wild-type seeds. Therefore, it appears that the antioxidant potential of transgenic oil-producing plants such as soybean, sunflower, and corn may be enhanced by overexpressing OsHGGT during seed germination.
authors.affiliation: National Institute of Crop Science, RDA, Suwon 441-857, Republic of Korea.
authors.forename: Yul Ho
authors.initials: YH
authors.lastname: Kim
authors.forename: Yu Young
authors.initials: YY
authors.lastname: Lee
authors.forename: Yong Ho
authors.initials: YH
authors.lastname: Kim
authors.forename: Man Soo
authors.initials: MS
authors.lastname: Choi
authors.forename: Kwang Ho
authors.initials: KH
authors.lastname: Jeong
authors.forename: Seuk Ki
authors.initials: SK
authors.lastname: Lee
authors.forename: Min Jung
authors.initials: MJ
authors.lastname: Seo
authors.forename: Hong Tai
authors.initials: HT
authors.lastname: Yun
authors.forename: Choon Ki
authors.initials: CK
authors.lastname: Lee
authors.forename: Wook Han
authors.initials: WH
authors.lastname: Kim
authors.forename: Sang Chul
authors.initials: SC
authors.lastname: Lee
authors.forename: Soon Ki
authors.initials: SK
authors.lastname: Park
authors.forename: Hyang Mi
authors.initials: HM
authors.lastname: Park
mesh_terms: D019883:Alkyl and Aryl Transferases / Q000235:genetics* / Q000378:metabolism; D000975:Antioxidants / Q000032:analysis* / Q000494:pharmacology; D015870:Gene Expression; D018525:Germination; D015227:Lipid Peroxidation / Q000187:drug effects*; D012275:Oryza / Q000201:enzymology*; D010936:Plant Extracts / Q000032:analysis* / Q000494:pharmacology; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000737:chemistry* / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D012639:Seeds / Q000737:chemistry / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D013025:Glycine max / Q000737:chemistry* / Q000235:genetics / Q000254:growth & development / Q000378:metabolism
chemical_list: D000975:Antioxidants; D010936:Plant Extracts; D010940:Plant Proteins; D019883:Alkyl and Aryl Transferases