title: [Comparison of soyasaponin and isoflavone contents between genetically modified (GM) and non-GM soybeans].
abstract: Soyasaponins and isoflavones are main secondary metabolites in soybeans. In this report we compared the content of secondary metabolites between genetically modified (GM) and non-GM soybeans. Six cultivars/lines of GM and six cultivars/lines of non-GM soybeans were extracted with methanol. Each extract was partitioned with aqueous methanol and hexane and the aqueous methanol fraction was partially purified by HP-20 and LH-20 column chromatography to afford crude soyasaponin and isoflavone fractions. The main A-type soyasaponin, acetylsoyasaponin A1 (AcA1), and the main B-type soyasaponins, soyasaponins I and II (I and II), in the crude fractions were identified by LC/MS analyses with authentic samples. The main isoflavones, daidzin, genistin, daidzein and genistein (DI, GI, DE and GE), in the crude fractions were identified by LC photo-diode array analyses with authentic samples. The contents of AcA1, I and II in the crude soyasaponin fractions and those of DI, GI, DE and GE in the crude isoflavone fractions were analyzed by reversed-phase HPLC. The average contents (mg/100 g) of AcA1, I, II and total of B-type soyasaponins in GM soybeans were 36.4 +/- 24.2, 51.2 +/- 11.8, 26.4 +/- 7.6 and 77.7 +/- 18.5, respectively, and those in non-GM ones were 22.3 +/- 14.7, 46.3 +/- 17.8, 19.8 +/- 9.1 and 65.9 +/- 26.9, respectively. The average contents (mg/100 g) of DI, GI, DE, GE and total isoflavones in GM soybeans were 93.1 +/- 15.5, 121.8 +/- 19.4, 0.073 +/- 0.178, 0.320 +/- 0.082 and 215.3 +/- 33.3, respectively, and those in non-GM ones were 78.8 +/- 34.6, 106.7 +/- 28.3, 2.206 +/- 4.468, 0.822 +/- 0.754 and 188.5 +/- 26.7, respectively. There were no statistically significant differences in soyasaponin and isoflavone contents between GM and non-GM soybeans. Therefore, it was estimated that the GM soybeans are equivalent to the non-GM ones in terms of the composition of the main secondary metabolites.
authors.affiliation: National Institute of Health Sciences: 1-18-1, Kamiyoga, Setagaya-ku, Tokyo 158-8501, Japan.
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Goda
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Akiyama
authors.forename: Emiko
authors.initials: E
authors.lastname: Suyama
authors.forename: Satoshi
authors.initials: S
authors.lastname: Takahashi
authors.forename: Junei
authors.initials: J
authors.lastname: Kinjo
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Nohara
authors.forename: Masatake
authors.initials: M
authors.lastname: Toyoda
mesh_terms: D030841:Food, Genetically Modified; D007529:Isoflavones / Q000032:analysis*; D009828:Oleanolic Acid / Q000031:analogs & derivatives* / Q000032:analysis; D012503:Saponins / Q000032:analysis*; D013025:Glycine max / Q000737:chemistry*
chemical_list: D007529:Isoflavones; D012503:Saponins; C056684:soyasaponin I; C106126:soyasaponin II; D009828:Oleanolic Acid