Exploring the Antioxidant, Anti-Inflammatory and Skin-Enzyme Inhibitory Activities of Balkan Ethnomedicinal Herbs Through In Vitro and In Vivo Screening

This study aims to evaluate the antioxidant and anti-inflammatory potential of dichloromethanic, methanolic and hydroalcoholic extracts of seventeen different selected Balkan medicinal herbs with ethnopharmacological interest, with the goal of identifying the most bioactive candidates for further investigation of their therapeutic efficacy in human diseases. A total of fifty-four extracts were initially screened; due to the high sample number, only the most active samples were advanced to subsequent assays in order to identify bioactive candidates with potential therapeutic efficacy in human diseases. The methanolic extract of Cotinus coggygria showed the highest radical scavenging activity (DPPH: 96.4% inhibition), the hydroalcoholic extract of Hypericum empetrifolium exhibited the most potent iron chelation (IC₅₀: 5.0 μg/mL) and the methanolic extract of Sedum sediforme presented the best anti-inflammatory activity in in vitro assays (LOX IC₅₀: 39.4 μg/mL, COX-1 inhibition: 93.1% and COX-2 inhibition: 94.0%). Furthermore, significant inhibition of tyrosinase and collagenase was observed for the methanolic extract of Cistus creticus (94.2% tyrosinase inhibition, 86.8% collagenase inhibition) and the methanolic extract of Cotinus coggygria (83.1% tyrosinase inhibition, 96.1% collagenase inhibition). In vivo, five promising plant extracts were selected and investigated in a carrageenan-induced paw edema model to assess their anti-inflammatory activity; the methanolic extract of Cotinus coggygria proved the most active, reducing mouse paw edema by 34% compared to the non-treated control. The results of this study indicate that several selected herbal extracts exhibit notable pharmacological activities. Given their antioxidant, anti-inflammatory, and inhibitory properties against enzymes related to skin function, these extracts warrant further in vivo and (pre)clinical investigation for potential use in cosmetic and pharmaceutical products targeting skin disorders associated with inflammation and oxidative stress.