abstract
Valorisation of discarded kiwifruits is proposed by extracting bioactive compounds using sustainable solvents namely deep eutectic solvents (DES). A screening of fifteen DES and several hydrogen bonding donor solvents was carried out. Extraction efficiency was measured in terms of antioxidant activity using DPPH and FRAP tests. The influence of solvents characteristics in particular DES structure, presence of ethanol or water, and pH of DES/water mixture on the antioxidant properties of the extracts was studied. Results show that kiwi peels ex-tracts obtained with DES based on carboxylic acids exhibit enhanced antioxidant activity compared to con-ventional solvents and alcohol-based DES with a maximum DPPH scavenging activity of 42.0 mg TE/g DW. Glycerol or ethylene glycol are also efficient at extracting antioxidant compounds with DPPH scavenging activity of 33.1 and 36.7 mg TE/g DW. Finally, a chemical analysis of extracts using HPTLC revealed that most active compounds extracted are polyphenolic compounds, presumably tannins.
keywords
DEEP EUTECTIC SOLVENTS; CHOLINE CHLORIDE; BIOACTIVE COMPOUNDS; WATER; CHROMATOGRAPHY; POLYPHENOLS; SOLUBILITY; PRODUCTS; WASTE; HPTLC
subject category
Chemistry; Food Science & Technology; Nutrition & Dietetics
authors
Chagnoleau, JB; Ferreira, AM; Coutinho, JAP; Fernandez, X; Azoulay, S; Papaiconomou, N
our authors
Ana Maria da Conceição Ferreira Takahashi
Junior Researcher
Projects
Collaboratory for Emerging Technologies, CoLab (EMERGING TECHNOLOGIES)
CICECO - Aveiro Institute of Materials (UIDB/50011/2020)
CICECO - Aveiro Institute of Materials (UIDP/50011/2020)
Associated Laboratory CICECO-Aveiro Institute of Materials (LA/P/0006/2020)
acknowledgements
The authors are grateful to the company OUI!GREENS for providing them out -of -caliber kiwifruits for this study. J -B C. is grateful to the EUR Spectrum - Graduate school of Formal, Physical and Engineering Sciences- for his Ph.D. financing. This work was partly developed within the scope of the project CICECO Aveiro Institute of Materials, UIDB/50011/2020, UIDP/50011/2020, and LA/P/0006/2020, financed by national funds through the Foundation for Science and Technology/MCTES.