Phenolic profile and antioxidant activity of hemp co-products following green chemical extraction and ex vivo digestion

The valorisation of biomass generated along the agri-food chain into co-products represents a valid approach to produce alternative and sustainable feed ingredients. Although to date, some co-products have already been included in the diets of livestock animals, the characterisation of hemp co-products (Cannabis sativa L.) is still at an early stage. For this, the aim of this this work was to investigate the nutritional and functional profile [total phenolic content (TPC) and antioxidant activity (ABTS, FRAP)] of hemp co-products [mix flowers and leaves (MFL), hulls (HLs) and hempseeds cake], after green chemical extraction (0% EtOH; 50% EtOH; 100% EtOH) and ex vivo digestion process. High-Performance Thin Layer Chromatography was performed on 50% EtOH chemical extracts to identify the main phenolic compounds. The results reported an interesting nutritional profile, although dependent on the processing to obtain the co-product. The functional aspect of the chemical extracts showed a higher TPC for MFL, especially after 50% EtOH extraction (3551.12 ± 98.54 mg TAE/100 g) identifying Quercetin, Kaempferol, Rutin, Chlorogenic acid, Ferulic acid, Cannabigerol and α-tocopherol as the main compounds present, a profile similar to that of HLs. This was also observed for ABTS (6950.10 ± 546.82 mg TE/100 g) and FRAP (130.05 ± 4.67 mg FeSO4/100 g). Ex vivo digestion confirmed the high functional profile of the two matrices. Despite this, it is important to emphasise that processing co-products are characterised by a high variability that may lead to different results and effects on the health and performance of monogastric animals.