Chemical Profile and Health-Promoting Activities of Crataegus laciniata (Rosaceae) Flowers

: In the present study, we focused our attention on Crataegus laciniata Ucria (Rosaceae), which is wild growing in western Sicily (Italy). The chemical profile of the C. laciniata flower's (CLF) ethanolic (70%) extract showed the presence of both C-flavonoid and O-flavonoid derivatives. Beyond the main metabolites, like hyperoside and vitexin, there are several luteolin derivates, in addition to catechin and epicatechin dimers or trimers. Regarding the antioxidant activities, CLF showed a strong ability to scavenge DPPH and ABTS radicals and a good Fe3+-reducing antioxidant power. The investigation into the key enzymes in diabetes showed strong inhibition on α-amylase and α-glucosidase, whereas the skin-whitening properties are linked to inhibitory effects on tyrosinase. Moreover, we employed Danio rerio (zebrafish) for toxicity assessment, as it represents an ideal in vivo model due to its high correlation with humans in response to pharmaceutical and cosmetic testing. Zebrafish embryos exposed to CLF (25-100 µg/mL) showed marked depigmentation compared to phenylthiourea (PTU), in addition to a high survival percentage and the absence of malformations. In conclusion, this experimental study outlines that C. laciniata flowers could be a potential source of bioactive compounds for application in the pharmaceutical and cosmeceutical industries.