Exploring the synergy between high-performance liquid chromatography (HPLC) and high-performance thin-layer chromatography (HPTLC) for the investigation of wine-making by-products

High-Performance Liquid Chromatography (HPLC) and High-Performance Thin-Layer Chromatography (HPTLC) have been shown to be very highly complementary techniques for both identification and quantification of flavonoid and non-flavonoid compounds extracted from wine-making by-products (white and red grape stalks, seeds and pomace). On the one hand, HPLC-Diode Array Detector (DAD) made possible, at the same injection, to discriminate between these classes of molecules by extrapolation at the right absorption wavelength. So, anthocyanins were exclusively identified (520 nm) followed by quantification with standard molecules. On the other hand, HPTLC paved the way for fingerprint, identification and quantification analysis showing that the matrices analysed contained other type of flavonoids in addition to those revealed by HPLC. At first, fingerprint evaluation served to establish the best conditions for the extraction of the target molecules, at the same time displaying the presence of both flavonoid and non-flavonoid species. Then, different HPTLC systems were developed for their identification leading to detect non-anthocyanic derivatives thanks to HPTLC low limit of detection. The present contribution falls within the scope of the project Valorizzazione sostenibile degli scarti della filiera vitivinicola per l'industria chimica e salutistica - VALSOVIT - funded by Emilia-Romagna Region (POR-FESR 2014-2020), aiming at the valorization of the waste of wine industry for the production of high added-value substances by sustainable technologie