Читать книгу Whole Grains and Health - Группа авторов - Страница 71

Phytochemicals mostly reside at the outer layers of cereal grains, particularly in the pericarp seed coat and aleurone layers, and can affect carbohydrate digestion and absorption in the gastrointestinal tract. Polyphenols such as phenolic acids found in whole grains have affinity to proteins like enzymes (Bandyopadhyay et al. 2012), and their inhibiting function on the activity of the α‐amylases and α‐glucosidases (maltase‐glucoamylase and sucrase‐isomaltase) have been documented (Shihabudeen et al. 2011; Forester et al. 2012; Mkandawire et al. 2013; Tu et al. 2013; et al. 2013; Simsek et al. 2015). In addition to their inhibition effect on hydrolytic enzymes, they also have been shown to interrupt the uptake of glucose by binding to the sodium‐glucose linked transporter, SGLT1 (Kobayashi et al. 2000) and glucose transporter 2, GLUT2 (Kwon et al. 2007; Stelmanska 2009; Manzano and Williamson 2010), or by reducing the expression of glucose transporters (Alzaid et al. 2013). Thus, both starch digestion and glucose absorption may be interfered by whole grain polyphenols, which could result in a reduction of postprandial glycemic response.