Exploring the Antimicrobial Properties Against Human Pathogens and Mode of Action of Various Extracts from Fredolia aretioides, an Endemic Medicinal Plant of Morocco and Algeria

Abstract

Background: Developing new antimicrobial medicines is one of the strategic objectives of the global action plan adopted by the World Health Organization to tackle antimicrobial resistance. Objective: Considering the fact that natural products derived from medicinal plants are an important source for discovering new antimicrobial compounds, we investigated here the antimicrobial properties and the mode of action of various extracts from Fredolia aretioides, an endemic medicinal plant of Morocco and Algeria, and belonging to the Chenopodiaceae family. Methods: Various extracts from F. aretioides were prepared and evaluated for their antibacterial activity against six bacterial species, and their antifungal activity against five fungi species. Chemicalgenetic screens were performed using a collection of Saccharomyces cerevisiae viable haploid deletion mutants spanning diverse biological processes. Results: The diethyl ether extract of roots was found to be active against Citobacter freundii, with a MIC of 400 µg/ml. Hydro-methanol, methanol and residual extracts from aerial parts and roots were active against all five fungi species tested. Our results showed that residual extracts were the most effective against the fungi tested. Residual extract from aerial parts was more potent than the residual root extract, with IC50’s of 60 µg/ml and 440 µg/ml, respectively. Chemical-genetic analysis in S. cerevisiae revealed that residual extracts might affect fatty acid and sphingolipid biosynthesis. Conclusion: All these findings suggest that F. aretioides is a promising source for the isolation of novel antimicrobial agents with novel mechanisms of action against human pathogens.