Solvent extraction of polyphenolics from the indigenous African fruit ximenia caffra and characterization by LC-HRMS
Date
2018
Journal Title
Journal ISSN
Volume Title
Publisher
MDPI
Abstract
Indigenous and non-commercial fruits can be an important source of antioxidant
polyphenols; however, the identity and content of polyphenols from non-commercial fruits are
often poorly described. The study aimed to extract, identify, and quantify polyphenols from the skin
of the indigenous Africa fruit Ximenia caffra, using solvent extraction. Three solvents (hexane, acetone,
and 70% v/v ethanol) over three extraction times (30, 60 and 120 min) were used in a 3² full factorial
experimental design to determine effects on polyphenol recovery, and individual polyphenolics were
characterised using liquid chromatography high-resolution mass spectrometry (LC-HRMS). Ethanol
was the most effective extraction solvent, and extracts had high levels of total phenolics and flavonoids
(65 mg gallic and 40 mg catechin equivalents per gram dry sample respectively), and high antioxidant
activity (18.2 mg mL-1 ascorbic acid equivalents). LC-HRMS positively identified 16 compounds,
of which 14 were flavonoids including flavonoid glycosides, and indicated that concentrations of
some flavonoids decreased for extraction times beyond 60 min. It was concluded that the fruit of
Ximenia caffra is rich in natural polyphenolic antioxidants; the present work identified and quantified
a number of these, while also establishing suitable solvent extraction conditions for the recovery of
these potentially high-value compounds.
Description
CITATION: Oosthuizen, D., et al. 2018. Solvent extraction of polyphenolics from the indigenous African fruit ximenia caffra and characterization by LC-HRMS. Antioxidants, 7(8):103, doi:10.3390/antiox7080103.
The original publication is available at http://www.mdpi.com
Publication of this article was funded by the Stellenbosch University Open Access Fund.
The original publication is available at http://www.mdpi.com
Publication of this article was funded by the Stellenbosch University Open Access Fund.
Keywords
Plant polyphenols, Flavonoids, Solvent extraction
Citation
Oosthuizen, D., et al. 2018. Solvent extraction of polyphenolics from the indigenous African fruit ximenia caffra and characterization by LC-HRMS. Antioxidants, 7(8):103, doi:10.3390/antiox7080103