Antifungal Activity of the essential oils of Plectranthus neochilus (Lamiaceae) and Tagetes erecta (Asteraceae) cultivated in Brazil

In recent years, the occurrence of clinical infections has increased dramatically. The considerable use of antifungal agents, there has been a remarkable increase in drug resistance among infections species [1]. The diseases most common caused by fungi are dermatomycoses and aspergillosis, where the dermatomycoses result from superficial fungal infections of the skin, hair, or nails, which could affect the human health and quality of life [2,3] not only in underdeveloped countries but also in elderly and immunocompromised patients worldwide [4]. Over the years, the dermatomycosis has had a considerable increase, being that their treatment is still based on the use of triazoles (fluconazole, itraconazole, voriconazole), imidazoles (ketoconazole), allylamines (terbinafine), and griseofulvin [5]. However, due to the increase in the number of individuals immunocompromised by HIV, transplanted individuals and individuals undergoing cancer treatment, there was a reduction in the number of effective drugs against many dermatopathogens [6]. In Brazil, human fungal infections are prevalent, but these diseases caused by fungi are not officially reportable [7]. About 80% of the cases of infectious pneumonic mortality in immunocompromised patients are caused by invasive aspergillosis (IA), where the health problems caused by Aspergillus include allergic reactions, lung infections, and infections in other organs [8]. Amphotericin is most frequently employed in conventional therapy, but its limited efficacy and poor patient tolerance to side effects culminates in response rates of only about 35% and high mortality [9]. Although the synthetic fungicides are effective, the development of fungal resistance, toxicity to non-target organisms and environmental problems is due to its continuous or repeated application [10]. The search for antifungal compounds from natural sources has increased over the last decade, and plants continue to be a major source of biologically active compounds that may provide lead structures for the development of new drugs [11]. In this scenario, essential oils constitute a rich source of bioactive chemicals and have been recently pointed out as a promising alternative against the pathogenic fungi [12-15].