Antibacterial, Antifungal, Cytotoxic and Genotoxic Activities of Different Extracts of Arabic and Myrrh Gums

Background: The Pharmaceutical companies are very interested in the discovery of new natural bioactive molecules with an impoortant effect and less toxicity, in order to replace old drugs, especially antibiotics which had lost their effectiveness following the spread of multi-resistant bacteria. This study was aimed to investigate, in vitro, some extracts (aqueous extracts, oily extracts and essential oils) of arabic and myrrh gums, plant exudates commonly used in folk medicine for treating several diseases. Materials and Methods: The antimicrobial activity against clinical bacterial and fungal strains was carried out using disk diffusion and broth dilution methods. Cytotoxic activity was mesured using the brine shrimp lethality bioassay determining the LC50 and genotoxic activity by the preincubation Ames Test using Salmonella strains TA100, TA98 and TA1535 treated with or without the metabolic activation (S9 fraction). Results: An interesting antimicrobial activity was demonstrated, especilly against Gram negative strains. Inhibition zones vary between 16 and 30 mm and MIC’s values between 15.62 and 250 μg/ml. All the tested extracts exhibited a bactericidal activity The arabic gum extracts showed no cytotoxic effect with LC50 > 100 µg/ml. Myrrh gum extracts showed a significant toxicity to the brine shrimp nauplii with LC50 < 100 µg/ml. Results of the Ames test indicated that all tested extracts did not possess genotoxic potential. Conclusion: Our study highlighted the antimicrobial potential of gums extracts, making them an excellent drug candidates against resistant pathogens.