Antituberculosis, antioxidant and cytotoxicity profiles of quercetin: a systematic and cost-effective in silico and in vitro approach

Abstract

The ineffectiveness and the slowdown of newer anti-TB drug approval rates directly indicate searching for potential alternative agents. However, validation of isolated phytochemicals through hit-and-trial experiments is more expensive and time-consuming. Simultaneously, cost-effective computational tools can recognize most potential candidates at an initial stage. The present study selected seven plant-derived polyphenols, then verified anti-TB and drug-ability profiles using advanced computational tools before the experimental study. Among all, the quercetin showed a potential docking-score within -8 to -11 kcal/mol than the standard isoniazid and ofloxacin, -5 to -10 kcal/mol. Additionally, quercetin exhibited a higher drug-ability score of 0.53 than isoniazid 0.19. Further, quercetin exhibited the minimum inhibitory concentration at 6 and 8 μg/mL, while ofloxacin showed at 2 μg/mL against InhA, and katG mutated Mtb-strains, respectively. Parallelly, quercetin showed promising free-radical-scavenging activity from nitric-oxide assay at IC₅₀ = 14.92 µg/mL, and lesser-cytotoxicity from cultured HepG2 cell lines at IC₅₀ = 159 µg/mL, respectively.

Keywords: Mycobacterium tuberculosis; anti-TB polyphenols; antioxidant potency; cytotoxicity profile; isoniazid-resistant-Mtb.