Antimicrobial activities of essential oils of plants species from Morocco against some microbial strains

Essential oils have important antibacterial activities and can successfully replace antibiotics, which show their inefficiency, especially against fungi and multi-resistant bacteria.

The main purpose of our research was to investigate the antibacterial and antifungal activity of essential oils from fifteen plants harvested in the Taroudant region.

In this work, the essential oils were extracted by hydrodistillation using a Clevenger-type apparatus. The method of disc diffusion in agar medium (aromatogram) is the one used to evaluate the activity of these essential oils against four pathogenic bacteria (Staphylococcus aureus, Escherichia coli, Bacillus sp., and Enterococcus cloacae) and two yeasts (Candida albicans and Cryptococcus neoformans).

Our findings, show that all of the plants' leaves yielded extremely aromatic essential oils that differed in look and color. Furthermore, the 93.33% of the fifteen essential oils that were evaluated proved to be effective against at least one kind of bacteria or fungus. This suggests that the proportion of essential oils with no antibacterial action was rather low, at around 7%. Our data also showed that the freshness or dryness of the plant at the time of harvest could affect the extraction rate of essential oils. This screening showed us that these essential oils present inhibitory activities towards the studied Gram+ bacteria, as well as a resistance against Gram-, in particular Enterococcus cloacae.

These essential oils can therefore be used in the prevention and treatment of certain infectious diseases and to fight against bacteria that are multi-resistant to the usual antibiotics.