Antifungal activity of medicinal plant extracts and phytocompounds: A review

The epidemiological data suggest that the incidence and prevalence of serious mycoses continues to be a public health problem. The increased use of antifungal agents has resulted in the development of resistance to these drugs. The spread of multidrug-resistant strains of fungus and the reduced number of drugs available make it necessary to discover new classes of antifungals from natural products including medicinal plants. Historically, herbs and spices have enjoyed a rich tradition of use for their medicinal properties and provide unlimited opportunities for new drug leads because of the huge chemical diversity. Assays of bioactive compounds have been reported with good antifungal properties in vitro or in vivo. It is almost impossible to discuss the various characteristics of these plants such as mode of action and extraction of active compounds in a single review. Therefore, we have focussed here mainly on the antifungal plant extracts, their use against pathogeinc and drug resistant fungi. The various classes of compounds such as phenolics, terpenoids, saponins, and alkaloids, etc., are discussed in detail. The new emerging classes of antifungal proteins and peptides are also reviewed briefly. In this chapter, we also describe the technical aspects related to the methodology for screening and identification of antifungal compounds. The technical aspects regarding the use of reliable methodology of extraction, screening, bioautography, and identification of pure compounds from crude extracts and fractions are also discussed here.