~ 127 ~ Journal of Medicinal Plants Studies 2022; 10(6): 127-132 ISSN (E): 2320-3862 ISSN (P): 2394-0530 https://www.plantsjournal.com JMPS 2022; 10(6): 127-132 © 2022 JMPS Received: 04-09-2022 Accepted: 09-10-2022 Bakarnga Via Issakou University of N'Djamena, Faculty of Human and Health Sciences, Laboratory of Pharmacology and Toxicology, B.P. 1027, N'Djamena, Chad Potaisso Djaryang University of N'Djamena, Faculty of Human and Health Sciences, Laboratory of Pharmacology and Toxicology, B.P. 1027, N'Djamena, Chad Bessimbaye Nadlaou University of N'Djamena, Faculty of Human and Health Sciences, Laboratory of Pharmacology and Toxicology, B.P. 1027, N'Djamena, Chad Issa Ramat Adam University of N'Djamena, Faculty of Human and Health Sciences, Laboratory of Pharmacology and Toxicology, B.P. 1027, N'Djamena, Chad Brahim Boy Otchom University of N'Djamena, Faculty of Human and Health Sciences, Laboratory of Pharmacology and Toxicology, B.P. 1027, N'Djamena, Chad Abdoullahi Hissein Ousman University of N'Djamena, Faculty of Human and Health Sciences, Laboratory of Pharmacology and Toxicology, B.P. 1027, N'Djamena, Chad Mbaigolmem Béral Valéry University of N'Djamena, Faculty of Human and Health Sciences, Laboratory of Pharmacology and Toxicology, B.P. 1027, N'Djamena, Chad Abdelsalam Tidjani University of N'Djamena, Faculty of Human and Health Sciences, Laboratory of Pharmacology and Toxicology, B.P. 1027, N'Djamena, Chad Corresponding Author: Bakarnga Via Issakou University of N'Djamena, Faculty of Human and Health Sciences, Laboratory of Pharmacology and Toxicology, B.P. 1027, N'Djamena, Chad Anti radical and antibacterial activities of the ethanolic extract bark of Anogeissus leiocarpus (Guill. Et Perr) from Chad Bakarnga Via Issakou, Potaisso Djaryang, Bessimbaye Nadlaou, Issa Ramat Adam, Brahim Boy Otchom, Abdoullahi Hissein Ousman, Mbaigolmem Béral Valéry and Abdelsalam Tidjani DOI: https://doi.org/10.22271/plants.2022.v10.i6b.1499 Abstract Introduction: Oxidative stress and bacterial infections are a public health problem in Chad. To reduce these problems, plant-based medicines were used to improve the development of traditionally drugs for infection treatments. The objective of this study was to evaluate the antiradical and antibacterial activities from ethanolic extract of Anogeissus leiocarpus. Material and Methods: In this study we used a stem bark of Anogeissus leiocarpus who used by different traditional practitioners in Chad for urinary infections treatment and diarrheal diseases caused by different types of bacteria (S. aureus, E. coli , S. typhi ). Also the antiradical activity was evaluated by the method of DPPH colorimetric and the antibacterial activity by the method of disk diffusion. A phytochemical study was carried out to link the structure to the activity. Results: Our result showed a rate of 13.2% of ethanolic extract. The phytochemical analysis revealed the presence of flavonoids, tannins, saponosides, alkaloids, sterols, terpenoids and anthocyanins. Also the ethanolic extract of Anogeissus leiocarpus revealed an antiradical activity by the decolorization of DPPH from an initial purple color to yellow. This extracts inhibited the growth of Staphylococcus aureus, Salmonella typhi and Escherichia coli at the minimum inhibitory concentrations (MIC) of 1.25 mg/ml, 2.5 mg/ml and 5 mg/ml respectively. Conclusion: Our result showed that the ethanolic extract bark of Anogeissus leiocarpus could be a potential provider of secondary metabolites with antiradical and antibacterial activities, allowing the development of a new molecules to fight against oxidative stress, cardiovascular diseases, and microbial infections. Keywords: Anogeissus leiocarpus, antiradical, antibacterial and Chad Introduction Many infection diseases contracted by humans are related to bacterial infections [1] . Among this number, gastroenteritis are among the most serious infectious diseases in humans [2] . It is estimated that between 11 and 21 million people infected by Typhoid Fever each year and between 128,000 and 161,000 die from it [3] . Pathologies that vary greatly in location and severity are caused by Staphylococcus aureus, one of the most common microorganisms responsible for nosocomial and community infections [4] . In Chad, the study conducted on the biochemical profile and phenotype resistant of bacteria responsible for nosocomial infections in the Urology and Traumatology departments of the National Reference University Teaching Hospital (NRUTH) of N'Djamena, revealed that Staphylococcus aureus and E. coli. Staphylococcus aureus are responsible for 18% and 19% of patients infections respectively in the Trauma and Urology departments of the same hospital, and the E. coli species was responsible for 60% of nosocomial infections in Urology and 7% in Traumatology [5] . During bacterial infections, the immune system was activated to protect the organism using certain phagocytic cells (macrophages, neutrophils) which produce free radicals by a variety of physiological mechanisms to destroy the bacteria [6] . Free radicals can interact with lipids, carbohydrates, DNA and proteins and their excessive production leads to oxidative stress, which is potentially involved in the development of numerous pathologies such as cancer, inflammation, diabetes, cardiovascular diseases, atherosclerosis, and ageing [7] .