ABSTRACT

With the rising concern of antibiotic resistance, natural remedies such as plant extracts are being explored for their therapeutic potential. Kalanchoe pinnata, a widely used medicinal plant, has been traditionally known for its antimicrobial properties.This study investigates the antimicrobial properties of aqueous and ethanol extracts derived from Kalanchoe pinnata against various clinical isolates of Staphylococcus aureus,Pseudomonas aeruginosa,Escherichia coli, Bascillus subtilis,Candida albicans and Aspergillus niger.Aqueous and ethanol extracts of the powered form of the leaves of Kalanchoe pinnata were obtained through cold maceration.Antimicrobial susceptibility was carried out using agar well diffusion method.The minimum inhibitory concentration (MIC), minimum bactericidal/fungicidal concentration (MBC/MFC) were determined using agar dilution method.

Four concentrations of the aqueous and ethanol extracts were tested against the clinical isolates (50mg,100mg,200mg,400mg) except for Escherichia coli which 25mg was included.The result using aqueous extract revealed positive insignificant relationship (p>0.5) between sensitivity and concentration in Staphylococcus aureus, Pseudomonas aeroginosa and Candida albicans whereas that of E.scherichia Coli, Bascillus subtilis and Aspergillus  niger were concentration dependent.In aqueous extract,E. coli gave 12mm zone of inhibition at 25mg concentration.At 400mg, the zone of inhibition(33mm) was higher than the standard(15mm).At 400mg Escherichia coli, Bascillus subtilis, Candida albicans and Aspergillus niger displayed a more inhibitory effect compared to the standard.Escherichia coli was the most affected by the aqueous extract.Ethanol extract revealed positive significant regression in Staphylococcus aureus,Pseudomonas aeruginosa,Escherichia coli and Candida albicans but insignificant variation in Bascillus subtilis while Aspergillus niger showed no zone of inhibition.At 400mg concentration, there was no significant difference between the zone of inhibition compared to the standard except Pseudomonas aeruginosa which varied significantly.Staphylococcus aureus,Escherichia coli and Bascillus subtilis were the most sensitive pathogens in all concentrations of ethanol extract.There was no significant difference in the inhibitory effect amongst all pathogens except in Escherichia Coli and Aspergillus niger where the aqueous extract was more effective than the ethanol extract.