RESEARCH ARTICLE
Optimization of Process on Extracting Flavonoids from Dry Onion Skins by Alkaline Method
Shi Guoqing1, 2, 3, Xiang Qisen1, 3, Fan Yichao1, Zhao Wenen2, Liu Yanqi*, 1, 3
Article Information
Identifiers and Pagination:
Year: 2015Volume: 9
First Page: 39
Last Page: 46
Publisher ID: TOCENGJ-9-39
DOI: 10.2174/1874123101509010039
Article History:
Received Date: 08/01/2015Revision Received Date: 29/03/2015
Acceptance Date: 07/04/2015
Electronic publication date: 26/6/2015
Collection year: 2015
open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: https://creativecommons.org/licenses/by/4.0/legalcode. This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Abstract
The flavonoids in dry onion skins were extracted by alkaline solution method. On the basis of single factor combined with ternary quadratic regression general rotary unitized design, the effects of several extraction parameters on the extraction efficiency of total flavonoids were investigated, including extraction times, pH of the extraction solution, material / extraction solution ratio, extraction time, and temperature. NaNO2-Al(NO3)3-NaOH method was used for the determination of total flavonoids. The optimal extraction conditions were as follows: two times of extraction; pH, 11; material / extraction solution ratio, 30 : 1; extraction temperature, 83.0 ~ 84.0 °C; extraction duration, 1.9 ~ 2.0 h. Under the above optimal conditions, the flavonoids extracted from dry onion skins yielded 2.82%.