Antimicrobial activities of Tephrosia vogelii against selected pathogenic fungi and bacteria strains

Area of Science:

• Phytochemistry
• Microbiology
• Pharmacology

Background:

• Pathogenic fungi (Candida albicans, Cryptococcus neoformans) and bacteria (Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Salmonella typhi) are developing resistance to conventional antifungal and antibiotic treatments.
• This resistance highlights the urgent need for novel antimicrobial agents.
• Tephrosia vogelii is a plant traditionally used to manage fungal and bacterial infections, suggesting its potential as a source of new antimicrobials.

Purpose of the Study:

• To evaluate the antimicrobial activities of leaf and root extracts of Tephrosia vogelii against specific fungal and bacterial pathogens.
• To determine the minimum inhibitory concentrations (MICs) of various Tephrosia vogelii extracts.

Main Methods:

• Leaf and root extracts of Tephrosia vogelii were prepared using different solvents (hexane, dichloromethane, methanol).
• Antimicrobial activity was assessed against Candida albicans, Cryptococcus neoformans, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, and Salmonella typhi.
• Minimum Inhibitory Concentrations (MICs) were determined using a two-fold serial dilution method in 96-well polystyrene microlitre plates.

Main Results:

• Hexane and dichloromethane extracts showed limited antifungal activity (MICs >10 mg/mL).
• Methanolic extracts from both roots and leaves demonstrated significant antifungal activity, with MICs of 5 mg/mL and 1.25 mg/mL, respectively.
• Dichloromethane and methanolic extracts exhibited antibacterial activity, with MICs ranging from 2.5-10 mg/mL and 0.625-5 mg/mL, respectively.

Conclusions:

• Tephrosia vogelii extracts possess significant antimicrobial properties against tested fungal and bacterial strains.
• The methanolic extracts, in particular, show promising activity, suggesting the presence of bioactive compounds effective against drug-resistant pathogens.
• Tephrosia vogelii represents a potential source for the development of new antimicrobial therapies to combat resistant infections.