Evaluation of Soyasaponin, Isoflavone, Protein, Lipid, and Free Sugar Accumulation in Developing Soybean Seeds

Abstract

A combination of analytical techniques was used to examine and quantify seed compositional components such as protein, lipid, free sugars, isoflavones, and soyasaponins during soybean development and maturation in two Korean soybean cultivars. Protein accumulation was rapid during reproductive stages, while lipid content was only relatively moderately increased. The major carbohydrate saccarides sucrose and stachyose constantly increased during the reproductive stage. Previously published results suggest that the free sugar and lipid content reached their maximal concentrations at a relatively early stage of seed development and remain constant in comparison to other chemical components. The malonylglucosides were the predominant isoflavone form followed by the glucosides, acetyl glucosides, and aglycone forms. As soybean seed matures, total soyasaponin concentration was constantly decreased until the R8 stage. Soyasaponin beta(g) was the major soyasaponin in DDMP-conjugated group B soyasaponins, followed by the non-DDMP counterpart soyasaponin I and soyasaponin A1. The ratio of total isoflavone to total soyasaponin in the developing soybean increased from 0.06 to 1.31. Protein, lipid, and free sugar contents in the developing soybean seeds showed significant positive correlations with conjugated isoflavones and total isoflavone concentration, while the lipid contents showed a negative correlation with the isoflavone aglycone. Protein, lipid, and free sugar contents showed a negative correlation with total group A and B soyasaponins and total soyasaponins; however, only the soyasaponin A content was significantly negatively correlated with free sugar content. Total soyasaponin content was negatively correlated with isoflavone content (r = -0.828 at p < 0.01).

Metabolism of Soyasaponin I by Human Intestinal Microflora and Its Estrogenic and Cytotoxic Effects

“…Soy contains numerous phytochemicals including isoflavones, phytic acid, phytosterols, and saponins Kim et al, 2006). Saponins are a family of steroid or triterpenoid glycosides found in a wide variety of plants (Oakenfull, 1981;Price et al, 1987).…”

Peran Fisiologis Sari Kedelai Hitam Diperkaya Mikroenkapsulan Minyak Sawit Mentah Pada Penderita Diabetes Melitus Tipe-2

“…Sejumlah penelitian telah mengungkapkan kelebihan kedelai hitam yaitu dari kulitnya yang mengandung antosianin dan tidak dimiliki oleh kedelai kuning pada umumnya. Selain itu kandungan biji kedelai hitam sendiri memiliki senyawa fitokimianya seperti antosianin, isoflavon, dan saponin (Kim et al, 2006;Slavin et al, 2013). Hasil penelitian Powell et al (2002), menyatakan nilai IG sari kedelai adalah 31, termasuk dalam kategori bahan pangan dengan nilai IG rendah sehingga baik untuk penderita DM-2.…”

Antioxidant Activity and Sensory Properties Carrot (Daucus carrota) Soyghurt

“…It has little saturated fat and no cholesterol, hence it is known to reduce the risk of heart disease (Kim et al, 2006, Jinapong et al, 2008. It is safe for people with lactose intolerance or milk allergy and for children with galactosemia.…”