A simple and reliable method for the simultaneous determination of nine phenolic compounds in barley and malted barley was established, using liquid chromatography-diode array detection-electrospray ionization tandem mass spectrometry (HPLC-DAD-ESI-MS/MS). The phenolic compounds can be easily detected with both systems, despite significant differences in sensitivity. Concentrations approximatel...

In the present investigation, we studied the modulating effects of several tea catechins and bioflavonoids on DNA methylation catalyzed by prokaryotic SssI DNA methyltransferase (DNMT) and human DNMT1. We found that each of the tea polyphenols [catechin, epicatechin, and (-)-epigallocatechin-3-O-gallate (EGCG)] and bioflavonoids (quercetin, fisetin, and myricetin) inhibited SssI DNMT- and DNMT1...

OBJECTIVE The purpose of this study was to investigate the biological effects of epicatechin (ECN), a crosslinking agent, on human dental pulp cells (hDPCs) cultured in collagen scaffolds. MATERIAL AND METHOD To evaluate the effects of ECN on the proliferation of hDPCs, cell counting was performed using optical and fluorescent microscopy. Measurements of alkaline phosphatase (ALP) activity, a...

Tea catechins promote glucose uptake in skeletal muscle cells. In this study, we investigated whether the addition of an acyl group to the C-3 position of catechins to generate 3-O-acyl-catechins promoted glucose uptake in L6 myotubes. 3-O-Myristoyl-(-)-epicatechin (EC-C14) and 3-O-palmitoyl-(-)-epicatechin (EC-C16) promoted glucose uptake and translocation of glucose transporter (GLUT) 4 in th...

Inspired by the potential functional activity of polyphenol compounds contained in raspberry (Rubus idaeus), we previously explored effects cultivation environment and maturity on polyphenolic profiles leaves fruits. Herein, building our previous studies, used high-performance liquid chromatography chromatography–mass spectrometry to profile five parts flowers (receptacles, sepals, pistils, sta...

We report the synthesis, electron paramagnetic resonance and electrochemical properties of a novel stable radical of the TTM series. Its strong electron acceptor ability has been tested with (-)-epicatechin, a natural polyphenolic antioxidant.

Natural medical plant is considered as a good source of tyrosinase inhibitors. Red vine leaf extract (RVLE) can be applied to a wide variety of medical disciplines, such as treatments for chronic venous insufficiency over many decades. This study investigated the tyrosinase inhibitory activity of RVLE containing gallic acid, chlorogenic acid, epicatechin, rutin, and resveratrol which are effect...

The optimization of the extraction of natural antioxidants from white tea has fostered intensive research. This study has investigated the effects of ethanol-water mixtures, temperature and time on the extraction of polyphenols and antioxidant components from white tea. The response surface methodology was applied to identify the best extraction conditions. The best conditions to maximize the e...

Two new compounds, cinnamic aldehyde cyclic d-galactitol 3'R,4'S-acetal (1) and cinnamomumolide (2), along with six known compounds, syringaresinol (3), lyoniresinol (4), 5,7,3'-trimethoxyl-( - )-epicatechin (5), 5,7-dimethoxyl-3',4'-di-O-methylene-( +/- )-epicatechin (6), 2-methoxyl-4-hydroxy cinnamyl aldehyde (7), and glucosyringic acid (8), have been isolated from the dried tender stems of C...

Studies involving the kinetic reaction between vanillin and condensed tannins were developed using a flow injection system with spectrophotometric determination. A solution of the monomeric compound (-)-epicatechin was used as the analytical standard. This compound was chosen due to its structure, which is similar to a polymeric unit of the condensed tannin present in plants. The results indica...