In-vitro Anti-Tuberculosis, Anti-Efflux Pumps and Anti-Biofilm Effects of Crinum Asiaticum Bulbs

Abstract

Drug resistant tuberculosis remains one of the major challenges associated with treatment and management of tuberculosis (TB) in the public health system and in clinical settings. In 2020, the World Health Organization (WHO) estimated that about 186,772 people died from drug-resistant tuberculosis out of the 500000 reported cases and this is alarming. There is a pressing need from every angle in drug discovery to develop novel compounds that could possess diverse mechanisms of action to tackle drug-resistant tuberculosis. The Crinum asiaticum bulbs extract are used ethno medicinally to treat upper respiratory tract infections and as well as wound healing agent. The aim of this work is to investigate the in-vitro anti-tuberculosis effect of Crinum asiaticum bulbs extracts and to assess the inhibitory properties against bacteria efflux pumps expression and biofilm formation. The results obtained showed that the Crinum asiaticum bulbs extracts (CAE) were effective in inhibiting Mycobacterium smegmatis (NCTC 8159) and Mycobacterium aurum (NCTC 10437) with minimum inhibitory concentration (MIC) of 125 μg/ml and 250 μg/ml against M. smegmatis and M. aurum respectively. The CAE markedly inhibited the efflux pumps of both M. smegmatis and M. aurum from expressing with the chloroform extract producing the greatest inhibition. The CAE (ethanol, methanol, chloroform and hexane) significantly (***ρ˂0.005) inhibited M. smegmatis’ and M. aurum’s biofilm formation in-vitro. Among the various extracts of Crinum asiaticum, the chloroform extract exhibited the greatest inhibition against M. smegmatis and M. aurum biofilm formation with significance levels of ***ρ˂0.005 and ***ρ˂0.005. In conclusion the CAE has anti-tuberculosis effect and could tackle drug resistant TB as exhibited through the anti-efflux and anti-biofilm forming properties of the extract against the selected Mycobacterium species.