The battle against biofilm infections: juglone loaded nanoparticles as an anticandidal agent.

In this study, juglone nanoparticles were prepared by single emulsion solvent evaporation method and their effect against Candida albicans biofilm was investigated in comparison with the free juglone and Fluconazole by performing XTT, crystal violet, standard plate count, confocal microscopy and membrane depolarization analyses. Juglone nanoparticles and free juglone were found to inhibit biofilm formation and pre-established biofilms (98-100%) at all doses tested, whereas Fluconazole did not cause a significant inhibition, even at the highest dose applied, especially against pre-established biofilms. Membrane depolarization analysis showed that free juglone and juglone loaded nanoparticles were effective on C. albicans membrane structure and have fluorescence quenching effect on DiSC3(5). It is extremely important that the antibiofilm activity of the juglone nanoparticles is similar to that of the juglone used at the same concentration, since similar effect is provided by using less active substance due to controlled release. Accordingly, it can easily be said that juglone loaded nanoparticles are much more effective in the formation and elimination of C. albicans biofilm than the free juglone and Fluconazole.

Enhancement of Antifungal Activity of Juglone (5-Hydroxy-1,4-naphthoquinone) Using a Poly(d,l-lactic-co-glycolic acid) (PLGA) Nanoparticle System.

This study aimed to synthesize and characterize juglone-entrapped poly(d,l-lactic-co-glycolic acid) (PLGA) nanoparticles and compare the antifungal properties of free juglone with its PLGA nanoparticle formulation for the first time. The juglone-loaded nanoparticles prepared using the oil-in-water (o/w) single-emulsion solvent evaporation method were characterized by the reaction yield (RY), encapsulation efficiency (EE), polydispersity index (PDI), particle size, zeta potential (ZP), FT-IR, and in vitro release properties and evaluated for their morphological features using SEM. The nanoparticle formulation had size, RY, ZP, EE, and PDI values of 212 nm, 66.91 ± 2.4%, -16.3 ± 0.7 mV, 70.66 ± 3.1%, and 0.083 ± 0.024, respectively. In vitro release showed a triphasic pattern with initial burst followed by sustained release and dormant phase over the study period, releasing about 72.8% in total after 42 days. The antifungal studies against Aspergillus flavus, Candida albicans, and Fusarium spp. using agar dilution and top agar dilution methods indicated that the juglone-encapsulated nanoparticle was more effective than free juglone. This study showed that the top agar method, which was applied for the first time on antifungal activity, is more suitable for the nanoparticular system based on sustained release. Therefore, PLGA nanoparticle formulations may be an important tool for application in many areas for the effective and beneficial use of hydrophobic compounds such as juglone.