Antibacterial and antioxidant activities of three endemic plants from Algerian Sahara

Saharan plants are known by their high content of antioxidant products like phenolic compounds due to the extreme climatic conditions. They constitute the basis of treatments used by local population for various diseases. The purposes of this study were to measure the total phenolic compounds and total fl avonoid compounds, to determine antioxidant capacity, and to evaluate the antibacterial activity of three wild Saharan medicinal plants.

Hexane and ethyl acetate fractions of ethanol:water extract and the residu of the extracted aqueous layer of Ferula vesceritensis fruits, Genista saharae aerial parts and Zilla macropterae fruits were assayed to determine their antibacterial activity using the disc diffusion method against: Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 25923) and Pseudomonas aeruginosa (ATCC 27853). In addition, the total phenolic compounds and total flavonoids and antioxydant activity using DPPH test of ethyl acetate fractions (EAF) of plant parts studied were investigated. Gallic acid, quercetin and vitamin C were used for these parameters.

Among the extracts tested, ethyl acetate fractions of all plants and hexane fraction of F. vesceritensis showed activity against S. aureus. Good activity was shown by EAF of G. saharae. According to the results, it is observed that Z. macropterae fruits possess a good antioxidant activity.

The results indicate that the ethyl acetate fraction of G. sahara Aerial parts possesses a good antibacterial activity against S. aureus, which justifies its use in traditional medicine for treating respiratory diseases. Furthermore, evaluation of in vitro antioxidant capacity of Ethyl acetate fractions of these plants, particular Z. macroptera fruits, has also provided interesting results. Zilla macroptera fruits may therefore be a good source of antioxidants.