The Antimycobacterial MICs, SARs and QSARs of Some Ethnobotanically Selected Phytocompounds Benson Muriuki

Abstract

The rise in cases of tuberculosis worldwide fuelled by the HIV/Aids pandemic highlights the need for new drugs that can shorten the duration of treatment, effectively treat MDR and XDR TB and be non interactive with available HIV/Aids treatment drugs. Fourty ethnobotanically selected phytocompounds and four conventional TB treatment drugs were screened for their in vitro inhibitory activity against two strains of Mycobacterium tuberculosis at the Central Reference Laboratory for TB (CRL) in Nairobi using the absolute concentration method at concentrations ranging from 0.05 to 120μg/ml. Compounds with better minimum inhibitory concentrations (MIC), than that of any of the four conventional TB treatment drugs, were identified as promising Leads. The study identified six promising Leads; three benzoquinones (114, 121 and 116), a flavone (141) an isoflavone (145) and an alkaloid (151). Structure activity relationships (SARs) and Quantitative structure activity relationships (QSARs) were generated for the flavonoid and the benzoquinone series members. QSARs were used in the prediction of structural modifications necessary for activity improvement and in the prediction of activity of untested compounds.