Antimycobacterial Activity of Allium Cepa and Allium sativum Hydroethanolic Crude Extracts against Pathogenic and...

Tuberculosis (TB) caused by Mycobacterium tuberculosis complex remains a leading cause of morbidity and mortality worldwide. The zoonotic infectious condition represents a never-ending challenge toward which drug discovery efforts are needed. The current study was designed to evaluate the in vitro antimycobacterial activity of hydroethanolic extracts from Allium sativum and Allium cepa bulbs and leaves, traditionally used against respiratory tract illnesses, including TB.

The phenotypic colorimetric microplate Alamar blue assay was used to study the antimycobacterial activity of the ethanolic extracts against six mycobacterial strains. Each experiment was run in triplicate. Data generated were analyzed using descriptive statistics to obtain mean minimum inhibitory concentration (MIC) values.

The A. sativum bulbs, A. sativum leaves, A. cepa bulbs, and A. cepa leaves exhibited MIC values of 19.5 µg/mL, 78.1 µg/mL, 78.1 µg/mL, and 19.5 µg/mL against the pathogenic mycobacterial strain, M. tuberculosis H37Rv (ATCC 27294), respectively.

In conclusion, the tested A. sativum and A. cepa bulbs and leaves have demonstrated significant activity against the pathogenic M. tuberculosis strain. This observation validates the ethnopharmacological use of the Allium species against TB. Further studies are required to isolate, elucidate the structure, and characterize the antimycobacterial compounds responsible for the observed activity. These will potentially contribute toward bioprospecting for a new class of ligands with activity against sensitive and drug-resistant strains of M. tuberculosis.