Oligomeric Proanthocyanidin Complex from Avocado Seed as A Promising α-glucosidase Inhibitor: Characteristics and Mechanisms

• Published in: Planta medica Vol. 89; no. 3; p. 316
• Main Authors: Nguyen, Thien Huu, Amen, Yhiya, Wang, Dongmei, Othman, Ahmed, Matsumoto, Masako, Nagata, Maki, Shimizu, Kuniyoshi
• Format: Journal Article
• Language: English
• Published: Germany 01.03.2023
• Subjects: Antioxidants; Glycoside Hydrolase Inhibitors - pharmacology; Persea; Proanthocyanidins - pharmacology; Seeds
• ISSN: 1439-0221
• DOI: 10.1055/a-1878-3916

Although considered an abundant source of agricultural by-products, avocado ( Mill.) seed, with several biological activities and bioactive components, might become a promising resource for phytopharmaceutical development. In this study, through bioassay-guided isolation of the main -glucosidase inhibitors in avocado seed, we discovered the major -glucosidase inhibitor to be avocado seed oligomeric proanthocyanidin complex (ASOPC). Thiolysis and UPLC-DAD-HRESIMS showed the presence of A- and B-type procyanidins, and B-type propelargonidin with (epi)afzelechin as extension unit. Mean degree of polymerization (mDP) of ASOPC was calculated as 7.3 ± 1. Furthermore, ASOPC appeared to be a strong, reversible, competitive inhibitor of -glucosidase, with IC value of 0.1 µg/mL, which was significantly lower than Acarbose (IC  = 75.6 µg/mL), indicated that ASOPC is a potential natural -glucosidase inhibitor. These findings would contribute to the direction of utilizing avocado seed bioactive components with the possibility to be used as natural anti-diabetic agents.