In-Vitro Antimycobacterial Activities of Thymus serrulatus (“Tosigne”) and Trigonella foenum gracium (“Abish”) Against Mycobacterium tuberculosis and Mycobacterium bovis

Author(s): Fikir Gete and Temesgen Kassa

Background: Tuberculosis (TB) is a serious infectious disease affecting many people across the world, particularly sub-Saharan Africans. Ethiopia is ranked 7th among the 22 high-TB burden countries in the world. Conventional chemotherapeutic control approaches have faced serious, flourishing drug resistance strains. Traditional herbal remedies have endeavored to supplement or replace ineffective drugs.

Methods: This study was conducted using an experimental study design to determine the antimycobacterial activity of leaves of Thymus serrulatus ("Tosign") and seeds of Trigonella foenum gracium ("Abish"). The ethanol and methanol crude extracts of the plants were tested against the Mycobacterium tuberculosis H37Rv reference strain, SIT149, and M. bovis (BCG and SB1176).

Results: Methanol and ethanol crude extracts of Thymus serrulatus and Trigonella foenum gracium have demonstrated promising activity against all the isolates of Mycobacterium species tested. Antimycobacterial activity was documented within an inclusive minimum inhibitory concentration (MIC) range of 0.78–50μg/ml for the extracts of two plant species. The highest antimycobacterial effect with a MIC of 0.78μg/ml was obtained in methanol extracts of Thymus serrulatus against most strains of M. tuberculosis and M. bovis isolates except M. tuberculosis H37RV which showed a MIC of 12.5μg/m. For Trigonella foenum gracium, the antimycobacterial effect with MIC was observed in the range of 0.78-12.5μg/ml against M. tuberculosis and M. bovis isolates with ethanol extraction.

Conclusions: This finding could serve as baseline information for further antimycobacterial agent study of these plants, and future studies ought to identify the exact bioactive chemicals involved in the antimycobacterial effect.