First phytochemical study of six tree and shrub species with high health-promoting potential from Madagascar: Innovative uses for food and medicinal applications

Traditional food and medicine play an important role in the daily lives of the local people of Madagascar for various reasons, including poor nutrition and access to health care, limited markets, and traditional values. This research aimed to investigate the potential properties of leaf infusions of six plant species used as traditional beverages by the local population of the Maromizaha protected forest through a phytochemical characterization of the composition of these plants and a preliminary assessment of their antioxidant capacity. Infusion of Euphorbia tetraptera presented the highest content of total polyphenols (9893.3 ± 401.6 mgGAE/100 gDW) and the highest antioxidant capacity (831.46 ± 44.08 mmol Fe2+/Kg DW), together with important values of benzoic acids, catechins, flavonols, cinnamic acids and organic acids. The Tina striata species also showed interesting levels of bioactive compounds in infusions, with high levels of polyphenols (420.17 ± 22.32 mgGAE/100 gDW), and antioxidant capacity (534.96 ± 5.78 mmol Fe2+/Kg DW), and organic acids (444.96 ± 43.43 mg/100 g DW). The comparison between leaf extracts and infusions confirmed that the intake of infusions by the local population may be, in general, a source of nutrients and bioactive molecules with antioxidant and anti-inflammatory activity. Finally, this study may help to improve the health of the local population, proposing these plants also for food purposes and adding new information on the Malagasy flora.