A green alternative approach to citrus peel bio-waste disposal: characterisation and bioactive potential

Currently, there is a great interest in promoting circular economy perspectives for the recovery of value-added bioactive compounds, potentially exploitable as bioactive natural ingredients, from agri-food bioresidues that causes serious environmental problems. The citrus juice industry is a powerful manufacturing industry that generates huge amounts of waste, mainly peels [1-2]. Material & Methods: A hydrodistillation system was used for the extraction of essential oils, polyphenols and organic acids from lemon, clementine and orange peels, subsequently analysed by GC-MS, UPLC-DAD-ESIMSn and UFLC-PDA respectively. Antioxidant, antimicrobial and/or cytotoxic activities were assessed. Results: The aqueous extract was rich in polyphenols such as hesperidin and sinapoil-O-glucosido. It showed antioxidant (IC50 TBARS = 0.98–1.4 mg/mL), antimicrobial (Staphylococcus aureus MIC = 2.5 mg/mL), and cytotoxic (AGS GI50 = 83 ± 4 mg/mL) activities, especially lemon peels. The essential oils recovered from lemon and clementine peels were rich in limonene (63.6-33,7%), nerol (10,9%) and linalool (5,3%), showing the most antioxidant (IC50 DPPH = 2.0 mg/mL) and antimicrobial (Campylobacter jejuni inhibition halo = 2.8 cm) potential.

Keywords

Bio-waste disposal Research Subject Categories::FORESTRY, AGRICULTURAL SCIENCES and LANDSCAPE PLANNING::Product science::Food science

URI

http://hdl.handle.net/10198/26348

Citation

Gómez-Mejía, Esther; Palá-Paúl, Jesús; Lobo Roiz, Custódio; Heleno, Sandrina A.; Calhelha, Ricardo C.; Dias, Maria Inês; Rosales-Conrado, Noelia; León-González, María Eugenia; Barros, Lillian; Madrid, Yolanda (2022). A green alternative approach to citrus peel bio-waste disposal: characterisation and bioactive potential. In 15th World Congress on Polyphenols Applications. Valencia