Article Sidebar
Keywords:
Helichrysum pedunculatum minimum inhibitory concentration log reduction time-kill bacteriostatic bactericidal antibacterial
Article Details
Issue
Section
Articles
Copyright for articles published in this journal is retained by the journal.
Main Article Content
Studies on the in vitro time kill assessment of crude acetone and aqueous extracts of Helichrysum pedunculatum leaves
Abstract
Helichrysum pedunculatum is used in folklore remedies to dress wound acquired after circumcision rite. This led to the study of in vitro antibacterial activities of this medicinal plant. Using standard
microbiological procedures, six bacteria species made up of four gram positive and two gram negative bacteria were screened for susceptibility to crude acetone and aqueous extracts of this plant. The
minimum inhibitory concentrations (MICs) of the acetone extract against the susceptible bacteria was 5.0 mg/ml while that of the aqueous extract ranged between 0.5 - 35 mg/ml. Average log reduction in viable cell count in time kill assay of the acetone extract ranged between 0.64 Log10 and 5.99 Log10 cfu/ml after 6 h of interaction, and between 5.99 Log10 and 6.06 Log10 cfu/ml after 12 h interaction in 1 × MIC and 2 × MIC, and between 0.10 Log10 to 0.33 Log10 cfu/ml after 6 h of interaction, and 0.23 Log10 and 0.56 Log10 cfu/ml after 12 h interaction in 1 × MIC and 2 × MIC for the aqueous extract. The effect of the aqueous extract was only bacteriostatic on both reference and environmental strains and the clinical isolates were outrightly resistant to this extract (not reported here). This is worrisome and this
could be one reason why, there is an incidence of high death rate resulting from circumcision wounds infection even after treating such wounds with H. pedunculatum leaf. Perhaps the plant could be of
more relevance in combination therapy and a source of resistance modifying principles which is the subject of on going studies in our group.
microbiological procedures, six bacteria species made up of four gram positive and two gram negative bacteria were screened for susceptibility to crude acetone and aqueous extracts of this plant. The
minimum inhibitory concentrations (MICs) of the acetone extract against the susceptible bacteria was 5.0 mg/ml while that of the aqueous extract ranged between 0.5 - 35 mg/ml. Average log reduction in viable cell count in time kill assay of the acetone extract ranged between 0.64 Log10 and 5.99 Log10 cfu/ml after 6 h of interaction, and between 5.99 Log10 and 6.06 Log10 cfu/ml after 12 h interaction in 1 × MIC and 2 × MIC, and between 0.10 Log10 to 0.33 Log10 cfu/ml after 6 h of interaction, and 0.23 Log10 and 0.56 Log10 cfu/ml after 12 h interaction in 1 × MIC and 2 × MIC for the aqueous extract. The effect of the aqueous extract was only bacteriostatic on both reference and environmental strains and the clinical isolates were outrightly resistant to this extract (not reported here). This is worrisome and this
could be one reason why, there is an incidence of high death rate resulting from circumcision wounds infection even after treating such wounds with H. pedunculatum leaf. Perhaps the plant could be of
more relevance in combination therapy and a source of resistance modifying principles which is the subject of on going studies in our group.
