MATERIALS AND METHODS: The effect of TH on both bacteria was investigated using MIC, MBC, growth curve, time-kill curve, scanning electron microscopy (SEM) and RT-qPCR.
RESULTS: The MIC of TH against P. aeruginosa and S. pyogenes was 18.5% (w/v) and 13% (w/v) respectively and MBC was 25% (w/v) for both bacteria. Spectrophotometric readings of at least 90% inhibition yielded MIC90 values of TH, 18.5% (w/v) and 15% (w/v) for P. aeruginosa and S. pyogenes respectively. A time-kill curve demonstrated a bactericidal with a 4-log reduction estimated within 8 hours. Using SEM, loss of structural integrity and marked changes in cell shape were observed. RT-qPCR analysis showed that TH reduced the pattern of gene expression in both bacteria, with a trend toward reduced expression of the virulence genes of interest.
CONCLUSION: This study suggests that TH could potentially be used as an alternative therapeutic agent for microbial infection particularly against these two organisms.