Recovery of bioactive compounds from red onion skins using conventional solvent extraction and microwave assisted extraction

  • Florina Stoica Faculty of Food Science and Engineering, Dunarea de Jos University of Galati
  • Gabriela Râpeanu Faculty of Food Science and Engineering, Dunarea de Jos University of Galati
  • Oana Viorela Nistor Faculty of Food Science and Engineering, Dunarea de Jos University of Galati
  • Elena Enachi Faculty of Food Science and Engineering, Dunarea de Jos University of Galati
  • Nicoleta Stănciuc Faculty of Food Science and Engineering, Dunarea de Jos University of Galati
  • Claudia Mureșan Faculty of Food Engineering, Tourism and Environmental Protection, Aurel Vlaicu University of Arad
  • Gabriela Elena Bahrim Faculty of Food Science and Engineering, Dunarea de Jos University of Galati
DOI: https://doi.org/10.35219/foodtechnology.2020.2.07
Keywords: extraction, red onion skins, antioxidant, anthocyanins, total phenolic content

Abstract

In this study two extraction methods, such as conventional solvent extraction (CSE) and microwave assisted extraction (MAE) were used for bioactive compounds extraction from red onion skins. The effects of several extraction parameters on the phytochemical content were investigated to discover which combination of parameters led to the highest concentration of phytochemicals. The results revealed that the optimal conditions for anthocyanin extraction (1.75±0.04 mg C3G/g DW) by CSE was achieved at 70% ethanol acidified with 0.1 N hydrochloric acid after 120 minutes of extraction at 25 °C. Also, the highest antioxidant activity (32.18±1.75 mM of Trolox/g DW) was obtained with 96% ethanol acidified with glacial acetic acid, after 3 hours of extraction at 25 °C. Meanwhile, for MAE the highest anthocyanin content of 1.60±0.05 mg C3G/g DW was found when using 50% ethanol acidified with 99.5% citric acid, at 735 W microwave power for 15 seconds of extraction. MAE with 96% ethanol and glacial acetic acid had the highest yield of antioxidant activity (33.41±0.59 mM of Trolox/g DW) at 315 W microwave power after 10 seconds of extraction. Therefore, the bioactive compounds from red onion skins might be available as a source of functional compounds useful in the pharmaceutical and food industry.

Published
2020-11-18
How to Cite
Stoica, Florina, Gabriela Râpeanu, Oana Viorela Nistor, Elena Enachi, Nicoleta Stănciuc, Claudia Mureșan, and Gabriela Elena Bahrim. 2020. “Recovery of Bioactive Compounds from Red Onion Skins Using Conventional Solvent Extraction and Microwave Assisted Extraction”. The Annals of the University Dunarea De Jos of Galati. Fascicle VI - Food Technology 44 (2), 104-26. https://doi.org/https://doi.org/10.35219/foodtechnology.2020.2.07.
Issue
Vol 44 No 2 (2020)
Section
ORIGINAL ARTICLES

Most read articles by the same author(s)

Obs.: This plugin requires at least one statistics/report plugin to be enabled. If your statistics plugins provide more than one metric then please also select a main metric on the admin's site settings page and/or on the journal manager's settings pages.