title: 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.
authors: College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
authors: Donglan
authors: D
authors: Xu
authors: College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
authors: Qingchuan
authors: Q
authors: Wang
authors: College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
authors: Wenqin
authors: W
authors: Zhang
authors: College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
authors: Bing
authors: B
authors: Hu
authors: College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
authors: Li
authors: L
authors: Zhou
authors: College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
authors: Xiaoxiong
authors: X
authors: Zeng
authors: College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
authors: Yi
authors: Y
authors: Sun
mesh_terms: D065089:Glycoside Hydrolase Inhibitors / Q000737:chemistry* / Q000302:isolation & purification; D030017:Ilex / Q000737:chemistry*; D007700:Kinetics; D015394:Molecular Structure; D010936:Plant Extracts / Q000737:chemistry* / Q000302:isolation & purification; D011801:Quinic Acid / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification; D012441:Saccharomyces cerevisiae / Q000201:enzymology*; D029701:Saccharomyces cerevisiae Proteins / Q000037:antagonists & inhibitors* / Q000737:chemistry; D000520:alpha-Glucosidases / Q000737:chemistry
chemical_list: D065089:Glycoside Hydrolase Inhibitors; D010936:Plant Extracts; D029701:Saccharomyces cerevisiae Proteins; C472707:caffeoylquinic acid; D011801:Quinic Acid; D000520:alpha-Glucosidases
keywords: caffeoylquinic acid; inhibitory activity; interaction; kudingcha; α-glucosidase