2026-04-28T17:55:36Zhttps://riubu.ubu.es/oai/request

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

00925njm 22002777a 4500 dc Trigueros Andrés, Ester author Benito Román, Oscar author Oliveira, Andreia P. author Videira, Romeu A. author Andrade, Paula B. author Sanz Díez, Mª Teresa author Beltrán Calvo, Sagrario author 2024-02 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. 2076-3921 http://hdl.handle.net/10259/8778 10.3390/antiox13020205 2076-3921 Hydrothermal treatment Onion waste Polyphenols Quercetin Antioxidant activity Antidiabetic potential Onion (Allium cepa L.) Skin Waste Valorization: Unveiling the Phenolic Profile and Biological Potential for the Creation of Bioactive Agents through Subcritical Water Extraction