title: Antitubercular and antibacterial activity of quinonoid natural products against multi-drug resistant clinical isolates.
abstract: Multi-drug resistant Mycobacterium tuberculosis and other bacterial pathogens represent a major threat to human health. In view of the critical need to augment the current drug regime, we have investigated therapeutic potential of five quinonoids, viz. emodin, diospyrin, plumbagin, menadione and thymoquinone, derived from natural products. The antimicrobial activity of quinonoids was evaluated against a broad panel of multi-drug and extensively drug-resistant tuberculosis (M/XDR-TB) strains, rapid growing mycobacteria and other bacterial isolates, some of which were producers of β-lactamase, Extended-spectrum β-lactamase (ESBL), AmpC β-lactamase, metallo-beta-lactamase (MBL) enzymes, as well as their drug-sensitive ATCC counterparts. All the tested quinones exhibited antimycobacterial and broad spectrum antibacterial activity, particularly against M. tuberculosis (lowest MIC 0.25 µg/mL) and Gram-positive bacteria (lowest MIC <4 µg/mL) of clinical origin. The order of antitubercular activity of the tested quinonoids was plumbagin > emodin ~ menadione ~ thymoquinone > diospyrin, whereas their antibacterial efficacy was plumbagin > menadione ~ thymoquinone > diospyrin > emodin. Furthermore, this is the first evaluation performed on these quinonoids against a broad panel of drug-resistant and drug-sensitive clinical isolates, to the best of our knowledge.
authors: Department of Pharmaceutical Technology, Jadavpur University, Kolkata, 700032, India; Department of Microbiology, Ashok Laboratory Clinical Testing Centre Private Limited, Kolkata, 700068, India.
authors: Diganta
authors: D
authors: Dey
authors: Ratnamala
authors: R
authors: Ray
authors: Banasri
authors: B
authors: Hazra
mesh_terms: D000995:Antitubercular Agents / Q000494:pharmacology*; D029788:Diospyros / Q000737:chemistry; D024901:Drug Resistance, Multiple, Bacterial; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D009169:Mycobacterium tuberculosis / Q000187:drug effects*; D010936:Plant Extracts / Q000494:pharmacology*; D029606:Plumbaginaceae / Q000737:chemistry; D011809:Quinones / Q000494:pharmacology*; D027823:Rhamnaceae / Q000737:chemistry
chemical_list: D000995:Antitubercular Agents; D010936:Plant Extracts; D011809:Quinones
keywords: Mycobacterium tuberculosis; clinical isolates; multi-drug resistance; natural products; quinonoids