Bowman-Birk and Kunitz Protease Inhibitors among Antinutrients and Bioactives Modified by Germination and Hydrolysis in Brazilian Soybean Cultivar BRS 133

Abstract

Soybean contains constituents that have antinutritional and bioactive properties. Enzymatic hydrolysis and germination can enhance the biological activity of these compounds in soybean. The objective of this study was to investigate the effect of germination, Alcalase (protease) hydrolysis, and their combination on the concentrations of antinutritional and bioactive compounds in Brazilian soybean cultivar BRS 133. A combination of germination and Alcalase hydrolysis resulted in the degradation of Bowman-Birk inhibitor (BBI), Kunitz trypsin inhibitor (KTI), and lunasin by 96.9, 97.8, and 38.4%. Lectin was not affected by any of the processing treatments when compared to nongerminated and nonhydrolyzed soy protein extract. Total isoflavones (ISF) and total saponins (SAP) increased by 16.2 and 28.7%, respectively, after 18 h of germination, while Alcalase hydrolysis led to the reduction of these compounds. A significant correlation was found between concentrations of BBI and KTI, BBI and lunasin, BBI and ISF, KTI and lunasin, KTI and ISF, KTI and SAP, lunasin and ISF, and ISF and SAP. Germination and Alcalase hydrolysis interacted in reducing BBI, ISF, and SAP. This study presents a process of preparing soy flour ingredients with lower concentrations of antinutritional factors and with biologically active constituents, important for the promotion of health associated with soybean consumption. In conclusion, 18 h of germination and 3 h of Alcalase hydrolysis is recommended for elimination of protease inhibitors, while bioactives are maintained by at least 50% of their original concentrations.

Kunitz trypsin inhibitor in addition to Bowman-Birk inhibitor influence stability of lunasin against pepsin-pancreatin hydrolysis

“…Previous studies have shown that processing could lead to reduction in the concentrations of BBI and KTI. Heat-induced protein aggregation led to reduction in KTI and BBI in soymilk (Chen, Xu, Zhang, Kong & Hua, 2014) while germination and hydrolysis led to modification of these protease inhibitors (Dia, Gomez, Vernaza, Berhow, Chang & de Mejia, 2012). As expected, pepsin and pepsin-pancreatin hydrolysis led to reduction in the concentration of these bioactive peptides (Fig.…”

Identification and characterization of transcript polymorphisms in soybean lines varying in oil composition and content

“…However, a number of genes whose protein products are not agronomically desirable due to their anti-nutritional effect are expressed in high quantities as well. Among those are genes encoding for protease inhibitors including Bowman-Birk serine protease inhibitors and Kunitz trypsin inhibitors that hamper the digestion of soybean proteins in animals and humans [52-54], and the lipoxygenases involved in oxidation of polyunsaturated fatty acids, which add unpleasant flavors to soybean products [33]. Many of the above mentioned genes show expression variation among the nine lines.…”

Germination of Phaseolus vulgaris and alcalase hydrolysis of its proteins produced bioactive peptides capable of improving markers related to type-2 diabetes in vitro

“…Bowman Birk and Kunitz inhibitors are trypsin/chymotrypsin inhibitors, which reduce the breakdown of proteins during digestion; α-amylase inhibitor reduces the breakdown of carbohydrates during digestion. Several studies demonstrated that legume germination is able to decrease the concentration of these anti-nutritional compounds (Aguilera et al, 2013;Dia, Gomez, Vernaza, Berhow, Chang, & de Mejia, 2012;Paucar-Menacho, Berhow, Gontijo-Mandarino, Chang, & de Mejia, 2010;Vidal-Valverde, Frias, Sierra, Blazquez, Lambein, & Kuo, 2002). The concentration of Bowman-Birk inhibitor in the non-germinated and non-hydrolyzed sample (G0-0h) was 6.6 mg/g of SP.…”