Improvements in the aqueous extraction of polyphenols from borage (Borago officinalis L.) leaves by pulsed electric fields: Pulsed electric fields (PEF) applications
Highlights
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- Antioxidants from borage leaves were extracted by pulsed electric fields treatment (PEF).
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- The phenolic release was performed with aqueous extraction.
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- Antioxidant capacity of borage leaves extracts was determined using ORAC assays.
Abstract
The aim of this work is to evaluate the effect of pulsed electric fields (PEF) (0–5 kV/cm) on the improvement of the aqueous extraction of polyphenols and antioxidant compounds from borage leaves. The extracts were assessed by using total polyphenols content (TPC) and antioxidant capacity through the assays of Folin–Ciocalteu and Oxygen Radical Absorption Capacity (ORAC), respectively. Extractions along the time were conducted at different temperatures (10, 25 and 30 °C). The PEF treatments incremented the TPC and ORAC values of the extracts between 1.3 and 6.6 times for TPC and between 2.0 and 13.7 times for ORAC, compared with the control. The TPC values were plotted and fitted to the kinetic model with an adjustment of 0.96 < R2 < 0.99. Significant differences between the treated and control samples were found as well in this study. This procedure enhances the antioxidant capacity of the extracts and reduces extraction times.
Graphical abstract
Keywords
- Borage;
- Pulsed electric fields;
- Antioxidant activity;
- Phenolic compounds;
- Aqueous extraction
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