Abstract

IN VITRO ANTIBACTERIAL AND ANTIBIOFILM ACTIVITIES OF ASCORBIC ACID AGAINST CLINICAL ISOLATES

*Anuya Aparna Rege, Dipti Bhushan Kolte and Disha Thakur

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Abstract

Infections with MDR and XDR gram negative bacteria pose a significant challenge to clinicians due to severely limited therapeutic options. Besides, health-related concerns are increasing due to the potential of biofilms to cause disorders by both device-related and nondevice related bacterial infections. Ascorbic acid could be a possible source of effective, cheap and safe candidate for eradication of biofilms. Hence, in the present in vitro study, Antibacterial and Antibiofilm potential of Ascorbic acid was evaluated against 6 Clinical Isolates, namely, Klebsiella aerogenes, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus mirabilis, Proteus vulgaris and Shigella flexneri as well as their Mixed Culture using various assays such as MIC, MBC, Agar Well Diffusion, Time Course study and Antibiofilm assay. The lowest MIC with Ascorbic Acid was noted against P. aeruginosa. The Antibiofilm activity was noted in the order of P. aeruginosa > P. mirabilis > Mixed Culture > K. pneumoniae > K. aerogenes > S. flexneri. Moreover, combination of Ascorbic acid + Ciprofloxacin revealed synergistic effect against Biofilms of K. aerogenes, K. pneumoniae and S. flexneri. Furthermore, in Time Course Study, Ascorbic Acid inhibited all Clinical Isolates and their Mixed Culture within 3 hours. Our previous study has revealed broad spectrum Antibacterial and Antibiofilm effects of Ascorbic acid against Standard Strains inhibiting gram positive as well as gram negative bacteria and their mixed cultures, whereas as, current in vitro study has exhibited Antibacterial and Antibiofilm activities against Clinical Isolates and their mixed culture. Hence, Ascorbic Acid could be a good candidate for further investigations.

Keywords: Ascorbic Acid, Antibacterial, Antibiofilm, Natural Products, Biofilm Assay, Mixed Culture.