Improving the quality of Vernonia amygdalina extract by ultrasound‐assisted extraction coupled with gas bubble flotation

Abstract

V. amygdalina (V.A) is an herb commonly used in folk medicine; it possesses various compounds with therapeutic capabilities. Traditional extraction approaches applied to this plant may destroy its bioactive compounds and inherently contaminate them with toxic organic solvents. In this study, ultrasound-assisted extraction combined with gas-bubble flotation was applied to increase V.A extraction yield. The efficiency of water maceration was increased by 200%, without the drawbacks of the conventional extraction methods. The total phenolic content yield was 189 ± 12.7 (mg GAE/g dry weight) with a condensation efficiency of 115 ± 5.7%; and the total flavonoid content was 6.44 ± 1.68 (mg QE/g dry weight). Additionally, the antioxidant activity of the condensed foam was enhanced up to 120%. Analysis of the extract by FTIR revealed the presence of extractable chemical families: sesquiterpene lactones, saponins and flavonoids, and that the chemical characteristics of the extract were also preserved This article is protected by copyright. All rights reserved. This is the author manuscript accepted for publication and has undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as