Looking for new antifungal drugs from flavonoids: impact of the genetic diversity of Candida albicans on the in-vitro response

In an era in which antimicrobial resistance is increasing at an alarming pace, it's very important to find new antimicrobial agents effective against pathogenic microrganisms resistant to traditional treatments. Among the notable breakthroughs in the past years of research in natural-drug discovery there is the identification and testing of flavonoids, a group of plant-derived substances capable of promoting many beneficial effects on humans. These compounds show different biological activities such as inhibition of neuroinflammation and tumor growth as well as antidepressant, antiarthritic, anti-hypercholesterolemic, antidiabetic, antiulcer and antiasthmatic activities. However, one of the most important effects of these phytochemicals is, undoubtedly, their antimicrobial activity against many microbial pathogens. In recent years, hundreds of scientific papers reported the inhibitory effects of flavonoids against pathogenic fungi but none of these has ever considered the inexorable genetic changes occurring within the populations of these microrganisms. Today, we have enough information to estimate genetic diversity within microbial species and recent data revealed that most of fungal pathogens shows a complex population structure in which no a single isolate can be designate as representative of the entire taxon. This is especially true for the highly divergent fungal pathogen Candida albicans, in which the assumption that one or few "standard strains" can represent the whole species is overly unrealistic and should be laid to rest. The goal of this article is to shed light on the extent of genetic variation in C. albicans and how this phenomenon can largely influence the activity of flavonoids against this species.