Bioavailability of cranberry bean hydroalcoholic extract and its inhibitory effect against starch hydrolysis following in vitro gastrointestinal digestion

Yi Chen Chiang; Chung Li Chen; Toong Long Jeng; Tzu Che Lin; Jih Min Sung

doi:10.1016/j.foodres.2014.08.049

Bioavailability of cranberry bean hydroalcoholic extract and its inhibitory effect against starch hydrolysis following in vitro gastrointestinal digestion

Food Res Int. 2014 Oct:64:939-945. doi: 10.1016/j.foodres.2014.08.049. Epub 2014 Sep 6.

Authors

Yi Chen Chiang¹, Chung Li Chen¹, Toong Long Jeng², Tzu Che Lin³, Jih Min Sung⁴

Affiliations

¹ Department of Agronomy, National Chung Hsing University, Taichung, Taiwan.
² Agricultural Research Institute, Wufong, Taichung, Taiwan.
³ Department of Food Science & Technology, Hungkuang University, Shalu, Taichung, Taiwan.
⁴ Department of Food Science & Technology, Hungkuang University, Shalu, Taichung, Taiwan. Electronic address: sungjm@sunrise.hk.edu.tw.

PMID: 30011737
DOI: 10.1016/j.foodres.2014.08.049

Abstract

This study used a simulated in vitro gastrointestinal digestion procedure to assess the bioavailability of a freeze-dried cranberry bean hydroalcoholic extract (polyphenol content of 28.73mgg^-1). The amount of polyphenols in 200mg of cranberry bean extract increased from 5.73 (non-digested original) to 11.39mg following gastric digestion, but decreased to 6.05mg during intestinal digestion. When cranberry bean extract was accompanied with starch for the digestion tests, the added cranberry bean extract exhibited a potent inhibitory effect against glucose release during simulated intestinal digestion, with IC₅₀ values of 472mg cranberry bean extract or 13mg polyphenols. A significant decrease in polyphenols was observed for the sample collected from dialysis phase, with only 11% of non-digested original polyphenols permeating through the dialysis membrane (0.63mg) and preserving an inhibitory effect against α-glucosidase to some extent. Therefore, polyphenol-rich cranberry bean extract may be used to manage postprandial hyperglycemia.

Keywords: Cranberry bean extract; Polyphenols; Simulated in vitro digestion; Starch digestion; α-Glucosidase.