The total phenolic content and antioxidant activities of the acetone extract and derived fractions from the walnut (Juglans regia) pellicle were estimated. The BuOH fraction exhibited the strongest antioxidant activity with the highest phenolic content. A phytochemical investigation of this fraction led to the isolation of three tannins, 2,3-hexahydroxydiphenoylglucose (1), pedunculagin (2) and 2,3,4,6-tetragalloylglucose (3). Pedunculagin showed high content and powerful activity, which implied that this compound plays an important role in the antioxidant activity of the walnut pellicle.
Xiaosan Zhang,Guangrong Huang,Hua Liu,Wenwei Chen,Jing Zhao,Zhenbao Jia,Fei Tao
Inhibiting α-amylase can lower postprandial blood glucose levels and delay glucose absorption, offering an effective approach for the development of antidiabetic diets. In this study, an active constituent with inhibitory activity against α-amylase was isolated and purified by bioassay-guided fractionation fromCarya cathayensisSarg. peel (CCSP). The active constituent was identified by NMR and Q-Exactive Orbitrap Mass Spectrometry as 5-O-p-coumaroylquinic acid (5-CQA). 5-CQA possessed strong inhibitory activity against α-amylase, with an IC50 value of 69.39 µM. In addition, the results of the kinetic study indicated that 5-CQA was a potent, reversible, noncompetitive inhibitor against α-amylase. The findings indicate that 5-CQA derived from CCSP has potential as a novel inhibitor against α-amylase, which can help mitigate postprandial blood sugar spikes, making it suitable for inclusion in antidiabetic diets.Keywords:Carya cathayensisSarg. Peel;postprandial hyperglycemia;5-O-p-coumaroylquinic acid;α-amylase inhibitor
Xizhe Fu,Tarun Belwal,Yihan He,Yanqun Xu,Li Li,Zisheng Luo
Natural deep eutectic solvent (NADES) has received increasing interest as a green alternative to traditional organic solvents for efficient extraction of bioactive compounds from natural sources. In this study, phytochemicals in Carya cathayensis Sarg. peels extracted with Choline chloride-Malic acid (ChCl-MA) were identified using UPLC-Triple-TOF/MS. Effect of NADES on phenolic composition, antioxidant properties and inhibition of α-glucosidase and α-amylase were evaluated. Furthermore, extraction mechanism caused by different solvents were investigated by quantum chemical calculation combined with molecular dynamic simulation. A total of 29 phytochemicals were identified, and catechin, procyanidin B1, 2,3-dihydroxybenzoic acid, pinocembrin, procyanidin B3, myricetrin were the most abundant compounds. The extract using ChCl-MA exhibited the highest phenolic compounds content, antioxidant capacity, and α-glucosidase and α-amylase inhibition activities. Larger solvent accessible surface area, more hydrogen bonds between ChCl-MA and extract, longer lifetime of the hydrogen bonds, and lower intermolecular interaction energy account for higher extraction efficiency of ChCl-MA.
危险品化学品经营许可证（带存储）