Antioxidant Activity In Vitro Guided Screening and Identification of Flavonoids Antioxidants in the Extract from Tetrastigma hemsleyanum Diels et Gilg.

Li Ding,Jiajia Zhang,Xiaomin Zhang,Valentina Venuti

doi:10.1155/2021/7195125

Abstract

This study aimed to investigate the extract with high antioxidant activity of Tetrastigma hemsleyanum Diels et Gilg and identify the antioxidant components in vitro. α, α-Diphenyl-β-picrylhydrazyl (DPPH) radical assay, Trolox equivalent antioxidant capacity (TEAC) assay, ferric reducing antioxidant power (FRAP), and hydroxyl radical scavenging method were used to screen the extract with high antioxidant activity. The antioxidant capacity of the extracts was evaluated by the free radical scavenging ability of DPPH. The ability of extracts to scavenge 2, 2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radical was evaluated by TEAC assay. The FRAP method was used to evaluate the ability of extracts to reduce Fe3+. The ability to scavenge hydroxyl radicals produced by the interaction of hydrogen peroxide and Fe2+ was measured by monitoring the change in the absorbance of the reaction mixture at 536 nm. Then, high-performance liquid chromatography-DPPH (HPLC-DPPH) and HPLC-hydroxyl radical scavenging methods were used to screen the antioxidant components in the extract. The molecular weight of the above antioxidant components was investigated using the qualitative analytical method of high-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (HPLC-Q-TOF LC/MS). Based on the concentrations of the samples (0.2–4 mg/mL), the DPPH free radical scavenging ability, ABTS+ free radical scavenging ability, hydroxyl free radical scavenging ability, and Fe3+ reducing ability of the ethyl acetate extract (EAE) were stronger than that of the crude extract (CE), petroleum ether extract (PEE), and n-butanol extract (BE). The EAE has higher antioxidant activity than CE, PEE, and BE. Six antioxidant components, rutin, quercetin, isoquercetin, astragalin, kaempferol, and kaempferol-3-o-rutoside, were identified in the EAE.

Highlights

Introduction e rhizome of Tetrastigma hemsleyanumDiels et Gilg, a Chinese folk herbal medicine, is used for the treatment of children with high fever, pneumonia, hepatitis, viral meningitis, scrofula, carbuncle, and furuncle [1]
The DPPH scavenging activity of ethyl acetate extract (EAE) and crude extract (CE) was similar to the sample concentrations of 0.2 mg/mL (P > 0.05) and 4 mg/mL (P > 0.05), respectively, while DPPH scavenging activity of EAE and all the other extracts is the largest difference at the sample concentration of 1 mg/mL (P < 0.05)
E DPPH scavenging activity of EAE was dose-dependent in the concentration range of 0.2–4 mg/mL and occurred in the following order: EAE > CE > butanol extract (BE) > petroleum ether extract (PEE) (Figure 2)

Summary

Introduction

Introduction e rhizome of Tetrastigma hemsleyanumDiels et Gilg, a Chinese folk herbal medicine, is used for the treatment of children with high fever, pneumonia, hepatitis, viral meningitis, scrofula, carbuncle, and furuncle [1]. Modern pharmacological studies have shown that Tetrastigma hemsleyanum Diels et Gilg has anti-inflammatory, analgesic [2], antiviral [3], antiliver injury [4, 5], antitumor [6, 7], and other pharmacological effects [8, 9]. Taraxerone, ergosterol, oleic acid, palmitic acid, myristic acid, hexadecylic acid, heptadecanoic acid, 9,12-octadecadienoic acid, α-linolenic acid, kaempferol, quercetin, and kaempferol-3o-neohesperidin were found in liposolubility extract of Tetrastigma hemsleyanum Diels et Gilg [11,12,13]. Xu analyzed 80% methanol ultrasonic extract of Tetrastigma hemsleyanum by HPLC-Q-TOF-MS and found that it contained kaempferol-7-o-rhamnose-3-o-glucoside, rutin, isoquercetin, kaempferol rutoside, astragaloside, and quercetin [12]. Flavonoids have various biological activities, such as the cardiovascular system [16, 17], antioxidant [18,19,20], anti-tumor [21,22,23], anti-inflammatory, and analgesic [24], and are one of the most and diverse phenolic groups of natural origin [25]; their antioxidation capability is a significant property

Methods

Results

Conclusion