2026-10-23T11:25:32Zhttps://riubu.ubu.es/oai/request

oai:riubu.ubu.es:10259/87782024-03-09T01:05:26Zcom_10259_4244com_10259_5086com_10259_2604col_10259_4245

Trigueros Andrés, Ester Benito Román, Oscar Oliveira, Andreia P. Videira, Romeu A. Andrade, Paula B. Sanz Díez, Mª Teresa Beltrán Calvo, Sagrario Hydrothermal treatment Onion waste Polyphenols Quercetin Antioxidant activity Antidiabetic potential Onion skin waste (OSW), the primary non-edible byproduct from onion processing, offers a renewable source of bioactive compounds. This study aims to valorize OSW through subcritical water extraction (SWE), aligning with a circular economy and biorefinery principles. SWE was carried out at 145 °C and 50 bar for 50 min in a discontinuous reactor, producing a phenolic-rich extract (32.3 ± 2.6 mg/g) dominated by protocatechuic acid (20.3 ± 2.5 mg/g), quercetin-4′-O-glucoside (7.5 ± 0.2 mg/g), and quercetin (3.2 ± 0.6 mg/g). Additionally, the extract contains sugars (207.1 ± 20.3 mg sucrose-Eq/g), proteins (22.8 ± 1.6 mg BSA-Eq/g), and free amino acids (20.4 ± 1.2 mg arginine-Eq/g). Its phenolic richness determines its scavenging activity against ●NO and O2●− radicals and its α-glucosidase and aldose-reductase inhibition without affecting α-amylase. Notably, the extract demonstrates significant α-glucosidase inhibition (IC50 = 75.6 ± 43.5 µg/mL), surpassing acarbose (IC50 = 129.5 ± 1.0 µg/mL) in both pure enzyme and cell culture tests without showing cytotoxicity to AGS, HepG2, and Caco-2 human cell lines. The extract’s bioactivity and nutritional content make it suitable for developing antioxidant and antidiabetic nutraceutical/food components, highlighting SWE’s potential for OSW valorization without using organic solvents. 2024-03-08 2024-03-08 2024-02 info:eu-repo/semantics/article 2076-3921 http://hdl.handle.net/10259/8778 10.3390/antiox13020205 2076-3921 eng Antioxidants. 2024, V. 13, n. 2, 205 https://doi.org/10.3390/antiox13020205 info:eu-repo/grantAgreement/AEI/Plan Estatal de Investigación Científica y Técnica y de Innovación 2017-2020/PID2020-116716RJ-I00/ES/TECNOLOGIAS DE FLUIDOS PRESURIZADOS PARA LA VALORIZACION DE SUBPRODUCTOS DE LA INDUSTRIA AGROALIMENTARIA: RECUPERACION DE PECTINA Y OTROS COMPUESTOS BIOACTIVOS DE ALTO VALOR/ http://creativecommons.org/licenses/by/4.0/ info:eu-repo/semantics/openAccess Atribución 4.0 Internacional MDPI