An innovative green extraction and re-use strategy to valorize food supplement by-products: Castanea sativa bud preparations as case study

This research takes place in the context of an Alcotra Italy-France trans-frontier project called FINNOVER, which includes among its objectives the “green” innovation of agro-industrial chains. Bud-derivatives are a category of natural products produced macerating meristematic tissues of trees and plants. They are quite expensive compared to other botanicals, since the collection period of their raw materials is extremely limited over the time. Pulsed Ultrasound-Assisted Extraction has been employed to extract further valuable material from the buds by-products remaining after the production of Castanea sativa Glyceric Macerates. UV–Visible spectra coupled with chemometrics were employed, as untargeted phytochemical fingerprints, to quickly screen the best experimental conditions of extraction: a duty cycle of 80%, an extraction time of 15 min and a solvent/ratio of 1/ 10. Targeted phytochemical fingerprints by HPLC have been used to identify and quantify the main bioactive compounds of the most promising marcs extract comparing it with the corresponding commercial Castanea sativa Glyceric Macerate. An innovative extraction and re-use strategy to obtain value-added products from botanicals by-products was developed in alternative to incineration or composting. It was applied to Castanea sativa buds production as case study, but it could be analogously applied for other herbal preparations.