Optimization of Flavonoid Extraction from Xanthoceras sorbifolia Bunge Flowers, and the Antioxidant and Antibacterial Capacity of the Extract.

Henghui Zhang,Xiaoli Wang,Runzhu Zhao,Shuying Li,Dongliang Zou,Buhailiqiemu Abudureheman,Dongliang He,Huifang Wang,Yongping Xu

doi:10.3390/molecules27010113

Abstract

In the present work, the extraction process of total flavonoids (TFs) from X. sorbifolia flowers by ultrasound-assisted extraction was optimized under the response surface methodology (RSM) on the basis of single-factor experiments. The optimal extraction conditions were as follows: ethanol concentration of 80%, solid–liquid ratio of 1:37 (g/mL), temperature of 84 °C, and extraction time of 1 h. Under the optimized conditions, the extraction yield of the TFs was 3.956 ± 0.04%. The radical scavenging capacities of TFs against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) were much greater than that of rutin. The results of antibacterial experiments indicated that the TFs displayed strong inhibitory activities on E. coli, S. aureus and Bacillus subtilis. Therefore, X. sorbifolia flowers can be used as a novel source of natural flavonoids, and the TFs have potential applications as natural antioxidants or antibacterial agents in the food and pharmaceutical industries.

Highlights

Xanthoceras sorbifolia Bunge is a monotype species endemic to China, belonging to the genus Sapindaceae [1]
When the concentration of ethanol exceeded 80%, the extraction yield of the total flavonoids (TFs) began to decline with the increase in concentration, which was probably due to the structural change of flavonoids in the extract caused by the high concentration of ethanol
The results indicated that the regression model was well-fitted and could be used to optimize the extraction process of TFs from X. sorbifolia flowers

Summary

Introduction

Xanthoceras sorbifolia Bunge is a monotype species endemic to China, belonging to the genus Sapindaceae [1]. It is a woody oil crop with a life span of more than 200 years, and it is a homologous medicine and food plant with high economic value [2,3]. In addition to the rich linoleic acid and linolenic acid in the oil of X. sorbifolia seeds, there is a range of flavonoids, polysaccharides, saponins, and other bioactive components in the flowers, leaves, and stem of X. sorbifolia [4]. Besides X. sorbifolia fruits, its flowers, leaves, and stem can all be used as medicine in traditional Chinese medicine, among which flavonoids are one of the main molecular components of its biological function [8]

Objectives

Methods

Results

Conclusion