From Field to Lab: Exploring the Phytochemical Potential of Calabrian Saffron (Crocus sativus L.) Biowaste

Saffron (Crocus sativus L.) is widely cultivated for the spice obtained from the stigmas, while the remaining floral biomass is discarded as biowaste. Accessing the phytochemical composition of these residues could enable their valorization as a low-cost and sustainable resource for nutraceutical applications. In this context, a quantitative 1H NMR-based metabolite profiling approach, complemented by HPLC-DAD and LC-MS, was employed to comprehensively characterize saffron biowaste. A total of 40 metabolites were identified and quantified by NMR, including amino acids (611.1 ± 36.5 mg/100 g FW), carbohydrates (2801.4 ± 33.7 mg/100 g FW), lipids (702.7 ± 28.2 mg/100 g FW), and saffron-specific compounds such as crocin (596.6 ± 21.5 mg/100 g FW), picrocrocin (1126.3 ± 18.9 mg/100 g FW), safranal (398.4 ± 14.8 mg/100 g FW), and crocetin (13.4 ± 0.4 mg/100 g FW). Targeted fractionation further allowed the identification of kaempferol 3-O-sophoroside (15.44 ± 0.61% w/w in dry ethanolic extract) and 3-hydroxy-γ-butyrolactone. Overall, the results highlight the rich metabolite composition of saffron production waste and support its potential reuse as a valuable source of functional ingredients within a circular economy framework.