Antimicrobial activity of fruits extracts of the wild jujube "Ziziphus Lotus (L.) Desf.

(2) Abstract— In Morocco, Wild jujube "Ziziphus Lotus (L.) Desf." is a very common fruit shrub in arid and semi-arid region. Fruits of this species are traditionally used for treatment of many diseases. The objective of this study is to evaluate in vitro the biological activity of the extracts of the fruits of this shrub, extracted successively by maceration with different organic solvents of increasing polarity (ether, dichloromethane and methanol), on four Gram negative and four Gram positive bacteria species and four species of filamentous fungi. All extracts showed an activity on different studied bac- terial species. At the concentration of 4000 µg/disk, the etheric and methanolic extracts were the most active by inducing growth inhibition diameters between 11 and 20 mm of Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, Klebsiella pneumoniae, Salmonella Typhi, Escherichia coli, Enter- ococcus faecalis and Pseudomonas aeruginosa. At the concentration of 20 mg/ml, these extracts showed an interesting activity on the four fungi spe- cies: Fusarium culmorum, Aspegillus ochraceus, Penicillium italicum, Rhizomucor sp. The inhibition rates ranged from 31 to 85% and 17 to 76% at the second and the fifth day of incubation, respectively. Based on chemical analyses, the fruits of wild jujube contain phenols, flavonoids and tannins, which explain their high antimicrobial activity. Indeed, a strong correlation was noted between the concentrations of these components in the fruits ex- tracts and their antimicrobial activity. These results confirm some uses of wild jujube in traditional medicine.