Estrogenic Activity of Glycitein, a Soy Isoflavone

Abstract

Glycitein (4' ,7-dihydroxy-6-methoxyisoflavone) accounts for 5−10% of the total isoflavones in soy food products. The biological activity of this compound has not been reported to date, although numerous studies have been performed with the other soy isoflavones, daidzein and genistein. Glycitein was isolated from soy germ to 99% purity. Weaning female B6D2F1 mice were dosed with glycitein (3 mg/day), genistein (3 mg/ day), and diethylstilbestrol (DES) (0.03 μg/day) in 5% Tween 80 by gavage for 4 days. A control group received an equal volume of 5% Tween 80 solution daily. The uterine weight increased 150% with glycitein (p < 0.001), 50% with genistein (p < 0.001), and 60% with DES (p < 0.001) compared with the control group. DES, 17β-estradiol, and three isoflavones (daidzein, genistein, and glycitein) were examined for their competitive binding abilities with 17β-(3H)estradiol to the estrogen receptor proteins of the B6D2F1 mouse uterine cytosol. The concentrations of each compound required to displace 50% of the (3H)estradiol at 5 nM in the competitive binding assay were 1.15 nM DES, 1.09 nM 17β-estradiol, 0.22 μM genistein, 4.00 μM daidzein, and 3.94 μM glycitein. These data indicated that glycitein has weak estrogenic activity, comparable to that of the other soy isoflavones but much lower than that of DES and 17β-estradiol. Glycitein (4′,7-dihydroxy-6-methoxyisoflavone) accounts for 5-10% of the total isoflavones in soy food products. The biological activity of this compound has not been reported to date, although numerous studies have been performed with the other soy isoflavones, daidzein and genistein. Glycitein was isolated from soy germ to 99% purity. Weaning female B6D2F1 mice were dosed with glycitein (3 mg/day), genistein (3 mg/day), and diethylstilbestrol (DES) (0.03 µg/day) in 5% Tween 80 by gavage for 4 days. A control group received an equal volume of 5% Tween 80 solution daily. The uterine weight increased 150% with glycitein (p < 0.001), 50% with genistein (p < 0.001), and 60% with DES (p < 0.001) compared with the control group. DES, 17 -estradiol, and three isoflavones (daidzein, genistein, and glycitein) were examined for their competitive binding abilities with 17 -( 3 H)estradiol to the estrogen receptor proteins of the B6D2F1 mouse uterine cytosol. The concentrations of each compound required to displace 50% of the ( 3 H)estradiol at 5 nM in the competitive binding assay were 1.15 nM DES, 1.09 nM 17 -estradiol, 0.22 µM genistein, 4.00 µM daidzein, and 3.94 µM glycitein. These data indicated that glycitein has weak estrogenic activity, comparable to that of the other soy isoflavones but much lower than that of DES and 17 -estradiol.

A Simple Synthesis of 7,4‘-Dihydroxy-6-methoxyisoflavone, Glycitein, the Third Soybean Isoflavone

“…The UV spectra, HPLC, mass spectrum, and 1 H NMR conformed to those reported for authentic glycitein , , The melting point for our synthesized glycitein (337−339 °C) compared well with the melting point reported for glycitein synthesized by Nógrádi and Szöllösy 8 (337−339 °C) and for glycitein isolated from soy germ by Song et al (337−339 °C).…”

“…The UV spectra, HPLC, mass spectrum, and 1 H NMR conformed to those reported for authentic glycitein. 3,4,8,11 The melting point for our synthesized glycitein (337-339 °C) compared well with the melting point reported for glycitein synthesized by No ´gra ´di and Szo ¨llo ¨sy 8 (337-339 °C) and for glycitein isolated from soy germ by Song et al 4 (337-339 °C). The yield of glycitein ( 6) by this microwave-mediated method was 26%, which compared well with the 36% yield reported by Chang et al 7 for genistein but lower than the 55% yield of Nogradi and Szollosy.…”

A Simple Synthesis of 7,4‘-Dihydroxy-6-methoxyisoflavone, Glycitein, the Third Soybean Isoflavone

“…The UV spectra, HPLC, mass spectrum, and 1 H NMR conformed to those reported for authentic glycitein , , The melting point for our synthesized glycitein (337−339 °C) compared well with the melting point reported for glycitein synthesized by Nógrádi and Szöllösy 8 (337−339 °C) and for glycitein isolated from soy germ by Song et al (337−339 °C).…”

“…The UV spectra, HPLC, mass spectrum, and 1 H NMR conformed to those reported for authentic glycitein. 3,4,8,11 The melting point for our synthesized glycitein (337-339 °C) compared well with the melting point reported for glycitein synthesized by No ´gra ´di and Szo ¨llo ¨sy 8 (337-339 °C) and for glycitein isolated from soy germ by Song et al 4 (337-339 °C). The yield of glycitein ( 6) by this microwave-mediated method was 26%, which compared well with the 36% yield reported by Chang et al 7 for genistein but lower than the 55% yield of Nogradi and Szollosy.…”

Molecular Understanding of Solvents and Glycitein Interaction during Extraction

“…Moreover, the experimental UV–vis spectral data for glycitein were λ max 257 nm (in the MeOH solvent). 1 Our calculated λ max is slightly larger than the experimental value, and this may be due to the DFT method used which overestimates the UV–vis spectra. Moreover, our calculations show that the max absorption is mainly formed by three excitations: +0.66(HOMO → LUMO + 1), +0.14(HOMO – 1 → LUMO + 1), and 0.15(HOMO – 1 → LUMO).…”

Antimicrobial Compounds Profile During Cheonggukjang Fermentation Against Xanthomonas oryzae pv. oryzae (Xoo)

“…The antioxidant activity of genistein was demonstrated by Record et al [16]. A high concentration of glycitein and daidzein served as good antimicrobial compounds produced during soy fermentation [17,19,20]. Our result revealed that the amount of isoflavonoid aglycone production was high at 72 h of fermentation, but the surfactin A and B content was high after 24 and 36 h of fermentation.…”

A Simple Synthesis of 7,4‘-Dihydroxy-6-methoxyisoflavone, Glycitein, the Third Soybean Isoflavone

“…The UV spectra, HPLC, mass spectrum, and 1 H NMR conformed to those reported for authentic glycitein , , The melting point for our synthesized glycitein (337−339 °C) compared well with the melting point reported for glycitein synthesized by Nógrádi and Szöllösy 8 (337−339 °C) and for glycitein isolated from soy germ by Song et al (337−339 °C).…”

“…The UV spectra, HPLC, mass spectrum, and 1 H NMR conformed to those reported for authentic glycitein. 3,4,8,11 The melting point for our synthesized glycitein (337-339 °C) compared well with the melting point reported for glycitein synthesized by No ´gra ´di and Szo ¨llo ¨sy 8 (337-339 °C) and for glycitein isolated from soy germ by Song et al 4 (337-339 °C). The yield of glycitein ( 6) by this microwave-mediated method was 26%, which compared well with the 36% yield reported by Chang et al 7 for genistein but lower than the 55% yield of Nogradi and Szollosy.…”

Molecular Understanding of Solvents and Glycitein Interaction during Extraction

“…Moreover, the experimental UV–vis spectral data for glycitein were λ max 257 nm (in the MeOH solvent). 1 Our calculated λ max is slightly larger than the experimental value, and this may be due to the DFT method used which overestimates the UV–vis spectra. Moreover, our calculations show that the max absorption is mainly formed by three excitations: +0.66(HOMO → LUMO + 1), +0.14(HOMO – 1 → LUMO + 1), and 0.15(HOMO – 1 → LUMO).…”

Antimicrobial Compounds Profile During Cheonggukjang Fermentation Against Xanthomonas oryzae pv. oryzae (Xoo)

“…The antioxidant activity of genistein was demonstrated by Record et al [16]. A high concentration of glycitein and daidzein served as good antimicrobial compounds produced during soy fermentation [17,19,20]. Our result revealed that the amount of isoflavonoid aglycone production was high at 72 h of fermentation, but the surfactin A and B content was high after 24 and 36 h of fermentation.…”

A Simple Synthesis of 7,4‘-Dihydroxy-6-methoxyisoflavone, Glycitein, the Third Soybean Isoflavone

“…The UV spectra, HPLC, mass spectrum, and 1 H NMR conformed to those reported for authentic glycitein , , The melting point for our synthesized glycitein (337−339 °C) compared well with the melting point reported for glycitein synthesized by Nógrádi and Szöllösy 8 (337−339 °C) and for glycitein isolated from soy germ by Song et al (337−339 °C).…”

“…The UV spectra, HPLC, mass spectrum, and 1 H NMR conformed to those reported for authentic glycitein. 3,4,8,11 The melting point for our synthesized glycitein (337-339 °C) compared well with the melting point reported for glycitein synthesized by No ´gra ´di and Szo ¨llo ¨sy 8 (337-339 °C) and for glycitein isolated from soy germ by Song et al 4 (337-339 °C). The yield of glycitein ( 6) by this microwave-mediated method was 26%, which compared well with the 36% yield reported by Chang et al 7 for genistein but lower than the 55% yield of Nogradi and Szollosy.…”

Molecular Understanding of Solvents and Glycitein Interaction during Extraction

“…Moreover, the experimental UV–vis spectral data for glycitein were λ max 257 nm (in the MeOH solvent). 1 Our calculated λ max is slightly larger than the experimental value, and this may be due to the DFT method used which overestimates the UV–vis spectra. Moreover, our calculations show that the max absorption is mainly formed by three excitations: +0.66(HOMO → LUMO + 1), +0.14(HOMO – 1 → LUMO + 1), and 0.15(HOMO – 1 → LUMO).…”

Antimicrobial Compounds Profile During Cheonggukjang Fermentation Against Xanthomonas oryzae pv. oryzae (Xoo)

“…The antioxidant activity of genistein was demonstrated by Record et al [16]. A high concentration of glycitein and daidzein served as good antimicrobial compounds produced during soy fermentation [17,19,20]. Our result revealed that the amount of isoflavonoid aglycone production was high at 72 h of fermentation, but the surfactin A and B content was high after 24 and 36 h of fermentation.…”