Inhibitory Activities of Caffeoylquinic Acid Derivatives from Ilex kudingcha C.J. Tseng on α-Glucosidase from Saccharomyces cerevisiae

Abstract

Polyphenols and caffeoylquinic acid (CQA) derivatives (3-CQA, 4-CQA, 5-CQA, 3,4-diCQA, 3,5-diCQA, and 4,5-diCQA) were prepared from Ilex kudingcha C.J. Tseng, and their effects and mechanisms on the activities of α-glucosidase from Saccharomyces cerevisiae were investigated in the present study. As results, the IC50 values for CQA derivatives were 0.16-0.39 mg/mL, and the inhibition mode of CQA derivatives was noncompetitive. On the basis of fluorescence spectroscopy and circular dichroism spectroscopy data, the binding constants and number of binding sites were calculated to be 10(6)-10(8) M(-1) and 1.42-1.87, respectively. CQA derivatives could bind to the enzyme mainly through hydrophobic interaction, altering the microenvironment and molecular conformation of the enzyme, thus decreasing the catalytic activity. To the authors' knowledge, this is the first report on α-glucosidase inhibitory mechanism by CQA derivatives from I. kudingcha, and the findings suggest a potential use of kudingcha as functional foods for the prevention and treatment of diabetes and related symptoms.

Inhibitory effects of Ligustrum robustum (Rxob.) Blume extract on α-amylase and α-glucosidase

“…One way is that they can prevent the postprandial hyperglycaemia through inhibiting the activities of carbohydrate hydrolyzing enzymes, such as α-amylase and α-glucosidase. The triterpenoids may show their inhibitory effects by inducing the variation of enzyme configuration or acting as non-competitive inhibitors (Kumar, Ghosh, & Pal, 2013;Liu et al, 2014;Xu et al, 2015). Thereby, the four compounds confirmed in this work could be largely responsible for the α-amylase and α-glucosidase inhibitory activities of LRE.…”

Simultaneous Qualitation and Quantitation of Chlorogenic Acids in Kuding Tea Using Ultra-High-Performance Liquid Chromatography–Diode Array Detection Coupled with Linear Ion Trap–Orbitrap Mass Spectrometer

“…The major CGAs in Kuding tea were well detected, and exhibited [M − H] − ions and product ions with abundant structural information ( Figure 1C,D). antidiabetic [5,6], anti-inflammatory [7], anti-atherosclerotic [8] and anticancer activities [9] in vitro or in vivo. CGAs are a large family of esters formed between quinic acid and one to four residues of certain cinnamic acids, most commonly caffeic, p-coumaric and ferulic [10,11].…”

“…It is traditionally applied for treating obesity, hypertension, cardiovascular disease, hyperlipidemia and various other diseases [1]. Meanwhile, the different extracts and active components from Kuding tea, including triterpenes, triterpenoid saponins and chlorogenic acids (CGAs), have been reported to possess significant antioxidative [2,3], antiobesity [4], antidiabetic [5,6], anti-inflammatory [7], anti-atherosclerotic [8] and anticancer activities [9] in vitro or in vivo. CGAs are a large family of esters formed between quinic acid and one to four residues of certain cinnamic acids, most commonly caffeic, p-coumaric and ferulic [10,11].…”

Three common caffeoylquinic acids as potential hypoglycemic nutraceuticals: Evaluation of α‐glucosidase inhibitory activity and glucose consumption in HepG2 cells

“…In the previous report, Xu et al. (2015) measured the α‐glucosidase inhibitory activities of CQAs from Ilex kudingcha C.J. Tseng using the traditional colorimetric assay.…”