Antioxidant and antifungal activities of the Cameroonian medicinal plant Annona muricata

Annona muricata L. (Annonaceae), commonly known as Soursop, Guanàbana or Graviola, is a small, upright evergreen tree of 5-6 m, with large, glossy, dark green leaves, which produces an edible fruit well known for its health properties. Although it is native of America, Annona muricata become established in many tropical countries of the world. The plant has been used in traditional medicine for many diseases, especially against infections and cancer. Effectively, it has been used in African herbal medicine systems for its sedative and antispasmodic properties, and also as hypotensive, insecticide, vermifuge, and for coughs, fevers, pain and skin diseases. Several chemical compounds have been isolated from the plant Annona muricata, and phytochemical investigations revealed the presence of alkaloids, tannins, coumarins, flavonoids, terpenoids. Among these compounds, researchers evidenced isoquinoline alkaloid annonaines, and acetogenins as the main active principles from Annona muricata. The aim of this research was to investigate the antioxidant capacity and antifungal activity in vitro of ethanolic extracts obtained from leaf, stem and root of Annona muricata. The antioxidant capacity has been evaluated using assays based on different mechanisms: the Oxygen Radical Absorbance Capacity (ORAC) assay, based on HAT reaction, and DPPH radical scavenging capacity assay, based on SET reaction. We also determined the Total Flavonoid Content (TFC) and the Total Phenolic Content (TPC) for each extract. Furthermore, the antifungal activity was studied by evaluated the MIC (minimum inhibitory concentration) and MFC (minimum fungicidal concentration) in different strains of Candida.