Enzyme inhibitory activity of Dioscorea nipponica Makito hydroethanolic extracts of leaves and tubers in relation to their major secondary metabolites  

作　　者：Aušra Adomėnienė Petras Rimantas Venskutonis 

机构地区：[1]Kaunas University of Technology,Department of Food Science and Technology,Radvilėnų pl.19,Kaunas,LT-50254,Lithuania

出　　处：《Food Bioscience》2022年第6期623-635,共13页食品生物科学（英文）

摘　　要：Different anatomical parts of Dioscorea nipponica Makito have been used in foods and folk medicines for their nutritional and pharmacological properties;however,the scientific data on enzyme inhibitory activities and phytochemicals in plant extracts remain rather scarce.Such information is important for expanding possible uses of plant origin preparations in nutrition.This study,using commonly applied assays,evaluated inhibitory activity of 70%ethanol extract of D.nipponica leaves and tubers against such physiologically important enzymes asα-amylase,α-glucosidase,acethylcholinesterase,and angiotensin-converting enzyme(ACE).Inhibition ofα-glucosidase and acethylcholinesterase required lower leaf extract concentrations as compared with other two enzymes.The IC50 values ofα-glucosidase andα-amylase inhibition were 66.08 and 438μg/mL,respectively,while the inhibition of ACE at 250–1250μg/mL was from 28.02±1.17%to 77.13±0.78%.The mode of inhibition ofα-glucosidase and acethylcholinesterase was evaluated by the kinetic studies.Leaf and tuber extracts displayed a mixed-type non-competitive mode ofα-glucosidase inhibition.Phytochemical composition of extracts was determined by UPLC-QTOF/MS and HPLC-UV methods.Leaf extract was remarkably stronger enzyme inhibitor than tuber extract and it may be explained by the differences in the secondary metabolite composition.Quinic,chlorogenic acids and quercetin glycosides,which are well-known enzyme inhibitors,were the main phytochemicals in the leaf extract,while steroidal glycosides,peptides and oligomeric sugars were the major constituents in the tuber extract.It is expected that new knowledge on D.nipponica will serve for its valorisation in developing new health beneficial ingredients for functional foods and nutraceuticals.

关 键 词：YAM Α-AMYLASE Α-GLUCOSIDASE Acethylcholinesterase Angiotensin-converting enzyme PHYTOCHEMICALS 

分 类 号：O62[理学—有机化学]