Introduction: The species we have chosen is Prosopis africana (Guill. & Perr.) of the Fabaceae family is a medium-sized shrub that can reach about 30 m in height and is widespread in tropical Africa, locally known in the Central African pharmacopoeia. It is a species widely used in traditional medicine for its therapeutic properties. Objectives: As part of the valorization of medicinal plants used in the Central African pharmacopoeia, the interest of this work is focused on ethnobotanical investigations, chemical screening and antioxidant activity of Prosopis africana. Methods: Four solvents of different polarities were used (cyclohexane, dichloromethane, acetone and methanol) for extraction. Qualitative analyses were based on staining reactions, followed by quantification by the 96-well plate reader to determine polyphenols, tannins, flavonoids and anthocyanins. Results: The extraction results showed that the methanol extract has the best yield of 14.45%. Qualitative analyzes revealed the presence of tannins, flavonoids, sterols, triterpenes and saponosides. The polyphenol content was better than the other families of compounds quantified (Table 2). It varies between 42,90 and 247.89 mg of gallic acid equivalent (EqAG) /g. The methanol and acetone extracts have strong antioxidant activity. They have respectively the percentages of inhibition of DPPH the values ​​98.47±00.70 and 98.55±00.10% (Figure 5). Principal component analysis (PCA) was performed using the «FactoMineR» and «factoextra» packages of the R software circle of variable correlation. The best Person (r) correlation coefficient obtained was 0.95 between polyphenols and DPPH inhibition. Conclusion: The phytochemical study revealed the presence of certain molecules such as polyphenols and alkaloids, which can give Prosopis africana (Guill. & Perr.) its therapeutic properties.

Introduction: Cola urceolata K. Schum is a plant of the Sterculiaceae family of the genus Cola. It is a species widely used in traditional medicine for its therapeutic properties and in food as a nutrient. Objectives: As part of the valuation of medicinal plants from the Central African Republic, the interest of this study is focused on ethnobotanical surveys, phytochemical analyzes and the antioxidant activity (DPPH) of Cola urceolata K. Schum. Methods: For the extraction, four solvents of different polarities (Cyclohexane: CYHA; Dichloromethane: DCM; Ethyl Acetate: EtOAc; Methanol: MeOH) were performed. Phytochemical tests were based on color reactions and chromatographic analyzes. The 96-well plate reader was used for quantitative analyzes of polyphenols, tannins, flavonoids and anthocyanins. Results: The results of the extraction showed that the methanol extract has the best yield of 8.21% followed by the cyclohexane extract 3.88%. The polyphenol content was better than the other quantified compounds. It varies between 8.90 ± 1.06 and 15.09 ± 1.58mg of gallic acid equivalent (EqAG). Qualitative screening showed the presence of alkaloids, anthocyanins, sterols and triterpenes. The inhibition of DPPH by the different extracts gave mean values ​​which varied between 4.65±2.85 and 15.17±4.60%. The results of principal component analysis (PCA) carried out using the «FactoMineR» and «factoextra» packages of the R software circle of correlation of variables. Conclusion: The phytochemical screening confirms the presence of certain molecules which can confer on Cola urceolata K. Schum its therapeutic virtues.