Green approach to valorize a side stream product: the rapeseed meal case

Rapeseed meal (RSM) is a byproduct of rapeseed processing for oil production. It is known to be rich in proteins, 1 phenolics, and flavonoids, 2 compounds exhibiting antioxidant and anti-inflammatory properties which make them attractive for use in functional foods, nutraceuticals, and cosmetics products. Various valorization strategies have been developed to fully utilize RSM, with a lot of extraction techniques 3 aimed at the extraction of bioactives.\r\nIn this study, we compared a classic ethanol Soxhlet extraction with a supercritical CO2-based approach, in the presence of ethanol as the modifier. This technique uses carbon dioxide in a supercritical state as a solvent to extract target compounds from a feedstock and is generally recognized as green and efficient. It offers several advantages over traditional extraction methods, such as low toxicity, high selectivity, and high purity of the extracted compounds. 4\r\nThe present work aims to valorize the RSM by developing "green" extraction processes of bioactive compounds based on the use of alcoholic solvents and/or supercritical CO2.\r\nAn emphasis was placed on improving the recovery of polyphenolic components, which were subsequently evaluated by means of NMR and HPLC-DAD analyses. In addition, the extraction residues were studied for their antioxidant properties through specific assays. On the basis of our results, a quantitative recovery hypothesis for bioactive-rich extracts reused in cosmetics 5 and nutraceuticals has been proposed.\r\nReferences\r\n1. Z. Zhang, S. He, H. Liu, X. Sun, Y. Ye, X. Cao, Z. Wu, H. Sun, Food Chem. 2020, 327, 126998.\r\n2. M. Zhang, C. Zheng, M. Yang, Q. Zhou, W. Li, C. Liu, F. Huang, J. Am. Oil Chem. Soc. 2019, 96, 303-317.\r\n3. S. Vuorela, A. S. Meyer, M. Heinonen, J. Agric. Food Chem. 2004, 52, 8202–8207.\r\n4. M. Zoccali, P. Donato, L. Mondello, Trends Analyt. Chem. 2019, 116, 158-165.\r\n5. D. Rivera, K. Rommi, M. M. Fernandes, R. Lantto, T. Tzanov, Int. J. Cosmet. Sci. 2005, 37, 496–505.