ANTIFUNGAL ACTIVITY OF BIPHENYL-2,6-DIETHANONE DERIVATIVES
Keywords:
Cryptococcus neoformans, Antifungal, Biphenyl-2, 6-diethanone, Laccase, MelaninAbstract
Objective: The objective of the study was to evaluate the antifungal activity of biphenyl-2,6-diethanone derivatives against Cryptococcus neoformans.
Methods: Antifungal activity of biphenyl derivatives were evaluated against C. neoformans. Zone of inhibition by disc diffusion method and minimum inhibitory concentration (MIC) using micro-broth dilution method was performed as per clinical and laboratory standard institute (CLSI). Melanin was extracted using 1M KOH, purified using 6M HCL and its reduction was assayed spectrophotometrically at 530 nm. Laccase activity was measured using L-DOPA as substrate and was assayed spectrophotometrically at 480 nm. Time kill assay was also performed to compare the antifungal potency of the test compound against azole drug.
Results: Zone of inhibition of 12 mm diameter was estimated against C. neoformans. MIC80 of compound 1e was calculated as 50µg/ml. 63.67% decrease in melanization and 57.44% laccase activity reduction was determined. The Time-kill assay illustrated that the compound 1e inhibited the growth of C. neoformans cells in almost the same duration as observed in fluconazole.
Conclusion: The outcome of in vitro antifungal studies indicated that compound 1e demonstrated maximum reduction of melanin and laccase activity in C. neoformans. In conclusion, biphenyl-2,6-diethanone derivatives possess significant antifungal property which can be explored further for lead generation.Â
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