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bioRxiv · 10.1101/2020.05.05.079897

Towards 'Ancientbiotics' for Biofilms: How can we bring traditional medicinal remedies out of treatise and into contemporary science?

Abstract

IntroductionTraditional medicinal remedies hold vast potential as novel antimicrobial agents, particularly for recalcitrant infection states such as biofilms. To explore their potential, it is important to bring these remedies out of ancient treatise and into present-day scientific evaluation. For traditional medical practices, this development pipeline starts with probing treatise for potential remedies and testing them for anti-biofilm effects, or the treatise to test phase. AimThe aim of this work is to present a primer for developing ancientbiotics against biofilms, that focuses on the treatise to test phase of the pipeline. Based on our approach and results, we provide insights into the considerations and challenges relevant to evaluating traditional remedies as anti-biofilm agents. MethodologyWe identified and reconstituted plant-based medicinal formulations from historical treatises of Indian traditional medicine, and analyzed their efficacy using widely-employed microtiter based assays, that constitute the cornerstone of biofilm studies. Measuring biomass and metabolic activity, we evaluated effects on biofilm formation and eradication of pre-formed biofilms, of Pseudomonas aeruginosa and Staphylococcus aureus. ResultsBased on recipes and preparation practices across several texts, and with modifications to ensure compatibility with modern scientific practices, three plant-based traditional remedies were identified and formulated in sesame oil (Bryophyllum pinnatum, Cynodon dactylon, and Ocimum tenuiflorum). We observed differential effects on biomass and metabolic activity on the biofilm formation and eradication of P. aeruginosa and S. aureus; highlighting the value of the microtiter-based assays as an initial screening tool for traditional remedies. ConclusionThrough this study, we provide insights into considerations relevant to the treatise to test phase of the ancientbiotics pipeline, such as identifying ancient remedies, reconstituting them with present-day modifications, and using in vitro assay formats for evaluation. The learnings in this primer will be relevant to both contemporary scientists and practitioners of ancient medicine, and will serve as a starting point for future studies exploring anti-biofilm approaches at the interface of historical and modern medicine.

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Madhusoodhanan, V., Kadam, S., Bandgar, A., Kaushik, K. S.. 2020-05-06. Towards 'Ancientbiotics' for Biofilms: How can we bring traditional medicinal remedies out of treatise and into contemporary science?. https://doi.org/10.1101/2020.05.05.079897

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