Chemical Assessment and Antimicrobial Activity of Solvent Extracts from Kalanchoe densiflora

Abstract

Kalanchoe densiflora leaves were sequentially extracted using hexane, ethyl acetate, chloroform, acetone and methanol. The solvents were evaporated through rotor evaporation under vacuum to yield five extracts. The extracts were then subjected to chemical and photochemical analyses to identify the components present and their functional groups. In addition the extracts were tested for antimicrobial activities against eight micro-organisms; Bacillus subtilis, Candida albicans, Escherichia coli, Klebsiella pneumoniae, Salmonella typhi, Staphylococcus aureus, Proteus mirabilis and Pseudomonas aeruginosa. The extracts were found to posses’ tannins, saponins, terpenoids, flavonoids and cardiac glycosides. It was also found that unsaturated bonds, carboxyl groups and aldehydes were present in the extracts. In addition, the extracts showed antimicrobial activity against Bacillus spp, E. coli and P. aeruginosa as indicated by presence of zones of inhibition. Acetonic and methanolic extracts were sensitive to P. aeruginosa, Bacillus spp. and S. aureus while hexane extract was highly sensitive to E.coli. K. densiflora extracts was found to have broad antimicrobial effect since it was active against gram positive and gram negative bacteria. Crude extracts from K. densiflora can be used in control of diseases such as; acute enteritis, pneumonias and opportunistic diseases amongst other diseases caused by these microorganisms.