An innovative approach for the recovery of nobiletin, hesperidin, and other phytochemicals from tangerine leaves (Citrus reticulata) by-products using a solvent mixture based on natural compounds

Author(s)

Sorita, Guilherme Dallarmi ; Rodriguez-Garcia, Camilo ; Strieder, Monique Martins ; Dominguez-Rodriguez, Gloria ; Montero, Lidia ; Bragagnolo, Felipe Sanchez ; Palomeque, Liliam ; Parada-Alfonso, Fabian ; Ibanez, Elena

• Document type: Journal article
• Source: Food Chemistry; v. 486, p. 14-pg., 2025-05-09.

Abstract

Citrus reticulata leaves, rich in phytochemicals, are underutilized by-products with sustainable valorization potential under Green Chemistry principles. This study developed an eco-friendly solvent combining thymol (Thy), oxalic acid (OA), and ethanol (EtOH) to extract nobiletin and hesperidin guided by COSMO-RS and high-intensity ultrasound (HIUS). The optimum solvent composition (0.9 % oxalic acid, 24.1 % thymol and 75 % EtOH) achieved higher yields of nobiletin (0.38 mg mL(- 1)), hesperidin (0.74 mg mL(- 1)) than pure EtOH (0.30 mg mL(- 1) of nobiletin and 0.64 mg mL- 1 of hesperidin). HPLC-DAD-MS/MS and GC-MS analyses revealed that the optimized extract had a more complex phytochemical profile with a richer composition than the EtOH extract. Furthermore, optimized Thy-OA-EtOH extract exhibited superior bioactivity, with enhanced antioxidant capacity and neuroprotective effects (IC50: 334.40 mg mL(- 1)) compared to HIUS-EtOH (IC50: 1482.20 mg mL- 1). This study highlights the potential of natural compound mixtures with HIUS for extracting phytochemicals from citrus leaves for food and pharmaceutical applications. (AU)

• FAPESP's process: 23/05722-6 - Biorefinery of the vegetable almond and peanut-based milk processes: study of technologies and alternative solvents to obtain bioactive compounds from their solid residues
• Grantee: Monique Martins Strieder
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• FAPESP's process: 23/12621-1 - Enhanced recovery of high-value compounds from agricultural by-products: green methods using predictive computational models and intensified extraction techniques
• Grantee: Felipe Sanchez Bragagnolo
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• FAPESP's process: 22/10469-5 - Application of in silico tools for the extraction of bioactive compounds from agro by-products by gas-expanded liquids and green switchable solvents
• Grantee: Felipe Sanchez Bragagnolo
• Support Opportunities: Scholarships in Brazil - Post-Doctoral