P016 Selected trans-Himalayan medicinal plants and their nano-particles express potent antifungal and antibiofilm activity against Candida auris and Candida glabarata

Abstract

Poster session 1, September 21, 2022, 12:30 PM - 1:30 PMNormal microbiota turned opportunistic pathogen Candida glabrata and pathogenic Candida auris are becoming major health concerns globally. Antimicrobial resistance is growing gradually now, even the newer antibiotics alone are not able to completely irradicate the resistant microorganisms. This dire situation reflects the need to have an alternative regime, especially with a diverse range of applicability. Nanoparticles synthesized from medicinal plants are emerging as potent antifungal agents to battle against fungal pathogens with unique antimicrobial properties. Secondary metabolites obtained from the herbs like alkaloids, carbohydrates, esters, flavonoids, glycosides, lignin, phenol, steroids, tannin, etc are robust therapeutic and immune-modulator compounds. The selected herbs (Aconitum heterophyllum, Allium ursinum, Paris polyphylla, Podophyllum hexandrum, Rheum austral, and Selenium vaginatum) in this study have a diversity of activity expression and had multiple medicinal usages traditionally. Extract of medicinal plants was produced and used as a reducing and stabilizing agent for silver nanoparticles preparation. After the synthesis of nano-particles antimicrobial activity was determined qualitatively and quantitatively. Biofilm activity and metabolic activity of the fungal cells after treatment with extracts and their nanoparticles were determined by crystal violet and XTT assay. Nanoparticles were characterized using UV-Vis, FTIR, and TEM. Extracts from the medicinal plants show potent antimicrobial activity, MIC ranging from 56 μg/ml to 625 μg/ml while their nanoparticles show activity in the range of 9.75 μg/ml to 80 μg/ml. The nanoparticles prepared were in the size range of 5-70 nm. Nanoparticles inhibited biofilm formation till MIC/64 with P <.001 and significantly (P <.01) eradiated the 24 h established biofilm at 64*MIC till 16*MIC. Uses of nanoparticles in the microbiological application are widely reported and have shown robust activity against almost all the organisms of the microbial world. Antifungal use in developing countries is uncontrolled and unregulated hence resistance to antimicrobial agents is increasing. These factors along with many others elevate the chances of nosocomial infections and globally C. glabrata accounts for 8%-10% of nosocomial candidiasis. Nanoparticles are more effective agents to fill the void created by the chemical-based drugs that are getting least effective in the treatment procedure as the drug resistance pattern in Candida is increasing dramatically. Plant-based reductants are good stabilizing agents also; they are environment friendly, non-hazardous, and less toxic. Less energy consumption and moderate condition preparation make green synthesis of nanoparticles most desirable process to proceed. Adding to this, if reductant has antimicrobial activity, it can enhance the potency of prepared nanoparticles.