Phytocomplexes produced by Hypericum perforatum and Gentiana lutea, native plants from Pollino National Park, a protected area in the middle of the Mediterranean sea

Among the goals promoted by the 2030 Agenda for Sustainable Development adopted by the United Nations Member States stands out the protection and the valorization of biodiversity and the importance of the ecosystem well-being (1). Within the ONFOODS project, two native plants from the Mediterranean basin, belonging to the area of Pollino National Park, Hypericum perforatum and Gentiana lutea, respectively, were investigated in the frame of non-structured nature-based solutions (NBS) for a sustainable environment. H. perforatum and G. lutea leaves, fruits and flowers were collected at different altitudes from both wild and cultivated species. Fresh plant material was allowed to dry under controlled conditions (40°C), then pulverized and extracted through hydroalcoholic maceration (EtOH 80%, 24h). The extracts phytochemical profile was assessed by means of HPLC analyses and through the determination of total phenolic content by Folin-Ciocalteau method. The antioxidant potential was investigated through ABTS assay, while the anti-adipogenic properties were evaluated thanks to Red Oil O assay in 3T3-L1 cellular model. The HPLC analyses revealed qualitative differences between H. perforatum extracts obtained by plants collected at different altitudes while a very similar, almost overlapping, pattern as regards different G. lutea extracts was determined. This trend was consistent with what emerged from the evaluation of both the total polyphenol content and the potential antioxidant activity of the investigated plants. In fact, while H. perforatum adapts to different altitudes by producing different amounts of secondary metabolites and by exerting antioxidant potential, with a trend that could be defined as altitude-dependent, G. lutea showed a stable trend at all collection sites. Moreover, H. perforatum leaf extracts, at the highest sub-cytotoxic dose of 40 μg/mL, previously selected through MTT assay, showed also interesting antiadipogenic properties at cellular staining with Red Oil O test, by reducing about 25% of cellular lipid droplets. This work highlighted the different adaptation and growth strategies applied by the investigated species. Thanks to the ability to respond to environmental changes, H. perforatum could be considered a potential candidate as ecological bioindicator, a useful tool for the assessment of health ecosystem.