Contribution of momilactones A and B to diabetes inhibitory potential of rice bran: Evidence from in vitro assays

This study was the first to detect the presence of the two compounds momilactone A (MA) and momilactone B (MB) in rice bran using liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS). By in vitro assays, both MA and MB exhibited potent inhibitory activities on pancreatic alpha-amylase and alpha-glucosidase which were significantly higher than gamma-oryzanol, a well-known diabetes inhibitor. Remarkably, MA and MB indicated an effective inhibition on trypsin with the IC50 values of 921.55 and 884.03 mu g/mL, respectively. By high-performance liquid chromatography (HPLC), quantities of MA (6.65 mu g/g dry weight) and MB (6.24 mu g/g dry weight) in rice bran were determined. Findings of this study revealed the alpha-amylase, alpha-glucosidase and trypsin inhibitors MA and MB contributed an active role to the diabetes inhibitory potential of rice bran. (C) 2019 The Authors. Production and hosting by Elsevier B.V. on behalf of King Saud University.