ANTIGLYCATION AND ANTIOXIDANT CAPACITY FROM SOYBEAN PHENOLIC EXTRACT

ANTIGLYCATION AND ANTIOXIDANT CAPACITY FROM SOYBEAN PHENOLIC EXTRACT

Vanize Martins Gênova1*, Annayara Celestina Ferreira Fernandes1, Érika Hiramatsu1, Lívia Dias de Queirós1, Juliana Alves Macedo1, Gabriela Alves Macedo1

1Food and Nutrition Department, School of Food Engineering, University of Campinas (UNICAMP), Campinas, São Paulo 13083-862, Brazil.

*E-mails: [email protected], [email protected], [email protected], [email protected], [email protected], [email protected]

Presentation: Oral ( ) Poster (x )

The glycation reaction occurs by the interaction of the carbonyl group of glucose or other reducing sugars with free amino groups derived from proteins, lipids and nucleic acids. This reaction results in the formation of a Schiff base that rearranges into complex molecules capable to cause a protein cross-linking, called Advanced Glycation End Products (AGEs). These products may contribute to complications of diabetes (Ahmed, 2005) and others chronic diseases. Several studies demonstrated that the consumption of soybean-based products is commonly associated with beneficial properties for health, including antioxidant and anti-inflammatory activities. Among the soybean bioactive compounds, the isoflavones are able to inhibit the formation of AGEs. In this context, the objective of this study was to investigate the antioxidant and antiglycation capacity of soybean phenolic extract. The concentration and distribution of isoflavones were evaluated by high-performance liquid chromatography (HPLC-DAD). The total phenolic content (TPC) was measured by Folin-Ciocalteu assay and the antioxidant activity was evaluated by DPPH and FRAP methods. The glycation models used were Bovine Serum Albumin (BSA)/fructose, BSA/methylglyoxal (MGO) and Arginine/methylglyoxal (MGO). The results showed that the phenolic extract contains 0.883 μg/ml of daidzin, 0.136 μg/ml of glicitin, 0.710 μg/ml of genistin, 0.093 μg/ml of daidzein, 0.640 μg/ml of glicitein, 0.170 μg/ml of genistein. The content of phenolic compounds was 9.74 μg of gallic acid/mg of lyophilized extract. The antioxidant activity was 8.94 μmol Eq.trolox/mg lyophilized extract by DPPH and 17.7 μmol Eq.trolox/mg lyophilized extract by FRAP method. The results of inhibition of glycation with 350 mg of lyophilized extract, in BSA/fructose, BSA/MGO and Arginine/MGO models, were 50.22, 41.56 and 51.40% of inhibition, respectively. According to Matsuda et al. (2003), soybean isoflavones (daidzin, genistin, daidzein, genistein) have effects on the formation of AGEs and capacity to eliminate free radicals. Lv et al (2011), suggest that genistein can efficiently inhibit the formation of AGEs, trapping reactive dicarbonyl species in vitro conditions. In conclusion, this study showed that isoflavones of soybean phenolic extract contain a great antioxidant capacity and they were able to inhibit the formation of AGEs. Therefore, the consumption of soybean phenolic extract could be a potential strategy for the prevention or treatment of glycation-related diseases.

Financial support: Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Key-words: Soybean, isoflavones, antiglycation.

Referências Bibliográficas:
Ahmed, N. (2005). Advanced glycation end products — role in pathology of diabetic complications. Diabetes Research and Clinical Practice, 67(1), 3–21.

H. Matsuda, T. Wang, H. Managi and M. Yoshikawa, Structural requirements of flavonoids for inhibition of protein glycation and radical scavenging activities, Bioorg. Med. Chem., 2003, 11, 5317–5323.

Lv, L.; Shao, X.; Chen, H.; Ho, C.T.; Sang, S. Genistein inhibits advanced glycation end product formation by trapping methylglyoxal. Chem. Res. Toxicol, v. 24, p. 579–586, 2011.