Inhibitory properties of polyphenols in Malus “Winter Red” crabapple fruit on α‐glucosidase and α‐amylase using improved methods

• Published in: Journal of food biochemistry 2021-10, Vol.45 (10), p.e13942-n/a
• Main Authors: Xiao, Zhengcao, Yang, Ruijia, Wang, Haojie, Cui, Xiaohui, Zhang, Yunyuan, Yuan, Yahong, Yue, Tianli, Li, Pengmin
• Format: Article
• Language: English
• Subjects: diabetes; inhibition; Malus; polyphenol compound; α‐amylase; α‐glucosidase
• ISSN: 0145-8884; 1745-4514
• DOI: 10.1111/jfbc.13942

To explore the inhibitory activity of polyphenols on α‐glucosidase and α‐amylase, 16 polyphenols were isolated, identified, and quantified in an edible Malus “Winter Red” crabapple fruit. The limitations of two traditional methods for α‐glucosidase and α‐amylase activity assay in vitro were assayed. An improved method based on an HPLC assay for α‐glucosidase and a colorimetric method coupled with a custom‐made mini‐column for α‐amylase were established. Compared with positive controls, acarbose and miglito, most polyphenols, especially the four aglycones (cyanidin, quercetin, phloretin, and 3‐hydroxyphloretin) showed higher inhibition rates on α‐glucosidase. None of the polyphenols showed higher inhibition rates on α‐amylase than acarbose, but most, especially the four aglycones, showed higher inhibition rates on α‐amylase than miglito. The Malus Winter Red fruit has great potential for postprandial blood glucose management as a potential diet therapy for diabetic patients. Sixteen kinds of polyphenol compounds were isolated, identified, and quantified in an editable crabapple fruit. Improved methods to avoid the interference of polyphenols on the analysis of the enzyme activity of α‐glucosidase and α‐amylase were established, respectively, and were used to analyze the inhibitory effects of the polyphenol compounds on the two enzymes. Most polyphenol compounds exhibited good inhibition on the enzymes activity, indicating that the crabapple fruit has great potential for postprandial blood glucose management.