Tuberculo
si
s (TB) cau
sed by
Mycobacterium tuberculosis remain
s an ongoing threat to human health. Several medicinal plant
s are u
sed traditionally to treat tuberculo
si
s in Ghana. The current
study wa
s de
signed to inve
stigate the antimycobacterial activity and cytotoxicity of crude extract
s from five
selected medicinal plant
s.
sSec_2">Material and methods
sp0040">The microplate alamar blue assay (MABA) was used for antimycobacterial studies while the CellTiter 96® AQ<sub>ueoussub> Assay, which is composed of solutions of a novel tetrazolium compound [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt; MTS] and an electron coupling reagent (phenazine methosulfate) PMS, was used for cytotoxic studies. Correlation coefficients were used to compare the activity of crude extracts against nonpathogenic strains and the pathogenic Mycobacterium tuberculosis subsp.tuberculosis.
sSec_3">Results
sp0045">Results of the MIC determinations indicated that all the crude extracts were active on all the three tested mycobacterial strains. Minimum inhibitory concentration values as low as 156.3 µg/mL against M. tuberculosis; Strain H37Ra (ATCC® 25,177™) were recorded from the leaves of Solanum torvum Sw. (Solanaceae). Cytotoxicity of the extracts varied, and the leaves from S. torvum had the most promising selectivity index. Activity against M. tuberculosis; Strain H37Ra was the best predictor of activity against pathogenic Mycobacterium tuberculosis subsp.tuberculosis (correlation coefficient=0.8).
sSec_4">Conclusion
sp0050">The overall results of the present study provide supportive data on the use of some medicinal plants for tuberculosis treatment. The leaves of Solanum torvum are a potential source of anti-TB natural products and deserve further investigations to develop novel anti-TB agents against sensitive and drug resistant strains of M. tuberculosis.
