Aims: The purpose of this study was to evaluate the in vitro antioxidant activities of Datura innoxia Mill. leaves and seeds harvested in Mali. Place and Duration of Study: Collection of plant materials were done at Kolondieba (Mali) in june 2016. Evaluation of polyphenols and flavonoids contents, determination of antioxidant activities were done at Laboratory of Plant and Food Biochemistry and Biotechnology of University of Sciences, Techniques and Technologies of Bamako (Mali) between august 2016 and March 2017. Methodology: The leaves and seeds were collected in Kolondieba, Mali. The phytochemical screening based on the standard methods of tube reactions has been performed with ethanol extracts. The quantitative estimation of total polyphenols was made by the Folin-Ciocalteu method and that of flavonoids by the use of aluminum trichloride. The in vitro antioxidant activities of the ethanol extracts was determined by three methods: the 1,1- diphenyl - 2- picrylhydrazyl (DPPH) test, the ferric reducing ability power (FRAP) test and the Phosphomolybdate test (PPM). Results: The phytochemical screening revealed that leaves and seeds of this plant contains alkaloids, polyphenols, flavonoids, coumarins, tannins, triterpenes and saponin. Phenolic contents of ethanol extracts are 30.97 ± 0.33 mg equivalent gallic acid / g in leaves and 14.02 ± 0.15 mg equivalent gallic acid / g in seeds; those of flavonoids are 15.13 ± 0.2 mg equivalent of quercetin / g in the leaves and 4.93 ± 0.41 mg equivalent of quercetin / g in the seeds. The three tests showed that the leaves have a higher level of antiradical activity in vitro than seeds. Conclusion: The results of this work showed that Datura innoxia Mill. has a good antioxidant activity which would justify its use as a potential source of natural antioxidants.

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Introduction: The objectives of this work consisted of a phytochemical study of the leaves and pulp of Ziziphus mauritiana Lam collected from the flooded and dried sites of Niono and Sévaré in Mali and to evaluate the biological activities of the extracts, i.e. the antiradical activity and hemolytic activity. Methods: Phytochemical analysis and biological activities were performed at the plant biochemistry and biotechnology laboratory of the FST / USTTB. The tannins and flavonoids were extracted by maceration, dosed by spectrophotometry then analyzed by HPLC and their antiradical activity was evaluated by the DPPH method. The saponosides were extracted by decoction and their hemolytic activity was evaluated on beef blood. Results: Tannins and flavonoids were abundant in the leaves and the pulp but saponosides were absent in the pulp. Calcium ions, carbonate ions and chloride ions were abundant in the leaves and pulp of Zizyphus mauritiana Lam from the dried site of Niono and the flooded site of Sévaré. HPLC chromatograms showed two peaks of gallic acid in the tannins extracts. Catechical tannins and flavonoids of the flooded sites have a greater antiradical activity than those of the dried sites. However, their antiradical activity remains lower than that of ascorbic acid whose IC50 was measured at 30 μg. Leaf saponosides from the flooded site of Niono and the dried site of Sévaré showed hemolytic activity on red blood cells of beef. Conclusion: The leaves and pulps of Zizyphus mauritiana Lam were rich in phenolic compounds and have interesting antiradical activity. The saponosides extracted from the leaves showed hemolytic activity.

Leaves and barks of Ficus platiphylla are used in traditional medicine in western Africa for treating bacterial infections. The aim of this work was to screen the biological activities of extracts of the plant. Three common bacterial strains were used in this study. The antiradical and antibacterial activities were assessed respectively by spectrophotometric and agar diffusion methods. The bark and leaves are very rich in dry matter, ash and as well as proteins and carbohydrates. Ethyl acetate was the best solvent to extract polyphenols (4.77-5.01 g/100 g) and flavonoids (1.97-3.32 g/100 g). Similarly, ethyl acetate extracts showed the best anti-free radical activity with IC 50 = 5.10 and 5.22 µg/ml for bark and leaves respectively. The aqueous and methanolic leaf extracts displayed the highest antibacterial activity on the Escherichia coli, with an inhibition diameter (ID) of 11.50 ± 0.50 mm. On Salmonella typhi, the most active antibacterial agents were found in leaf ethyl acetate extracts with ID = 15.33 ± 0.58 mm. These extracts have the same efficacy as the commercial antibiotic ciprofloxacin (positive control) which displayed an ID of 15.33 ± 0.76 mm. Finally, S. aureus was highly sensitive to ethyl acetate extracts of the barks: ID = 15.50 ± 1.32 mm (p-value = 4.10E-6 < 0.05). The richness in secondary metabolites associated with the antiradical and antibacterial activities justify use of F. platiphylla in traditional medicine. This study shows that F. platiphylla could be a valuable medicinal plant for the management of common bacterial infections.

Aims: This study aimed to assess the in vitro antibacterial effects of extracts from four wild food fruits: Balanites aegyptiaca, Saba senegalensis, Ziziphus mauritiana, and Raphia sudanica. Place and Duration of Study: The samples of plant material were collected at Banamba and Sikasso, Mali between January and May 2018. The bacterial strains were collected at Research Centre for Biological Food and Nutritional Sciences (CRSBAN), University Professor Joseph Ki-Zerbo; Ouagadougou, Burkina Faso. The experimental parts were also carried out at CRSBAN from October 2019 to January 2020. Methodology: The fruit extracts were screened for antibacterial activity against Escherichia coli, Salmonella typhi, S. aureus, B. cereus, and L. monocytogenes strains. The diameters of the inhibition zones (ID), the minimum inhibitory concentrations (MIC) as well as the minimum bactericidal concentrations (MBC) were evaluated using agar diffusion method. Results: The findings revealed that these parameters have varied as a function of fruit species and/or their zones of provenances. All fruit extracts showed significant growth reducing effect against all the tested bacteria. The extracts from R. sudanica have exhibited the strongest growth-inhibiting activity specifically against E. coli (ID = 15.33±0.58 mm) and Salmonella typhi (ID = 18.00±1.00 mm) with lower MIC (from 2.08±1.44 to 5.83±1.44 mg/mL). Moreover, the MBC/MIC ratios revealed that the extracts from the studied fruits possess mainly bacteriostatic effects towards the tested strains. Conclusion: These findings support local therapeutics properties attributed to these fruits. They also demonstrate that, in addition to their nutritional values, these edible fruits could be used for developing antibiotics to treat infectious diseases and food poisoning.