Evaluation of green synthesized silver nanoparticles utilizing freeze dried curcumin nanocrystals against multidrug resistant bacteria, in-vitro and in-vivo study

Development of multidrug-resistant (MDR) organisms is becoming a critical clinical problem for the management of numerous bacterial infections. Investigating other antibacterial drugs is urgently needed that are nontoxic and effective by different mechanisms. This study was aimed to develop silver nanoparticles (AgNPs) utilizing a green synthetic approach involving highly solubilized curcumin in freeze dried nanocrystals (CrNC) as a natural flavonoid reducing agent. The fabricated silver nanoparticles were typically found to be spherical in shape with particle size distribution in the range of 10–50 nm and zeta potential of -18.3 ± 2.69mV. UV-Vis spectroscopy presented a characteristic plasmon peak of silver at 410 nm. The minimal inhibitory concentrations (MICs) of the prepared AgNPs against Staphylococcus aureus ATCC® 43300™*, Escherichia coli ATCC® 8739™*, Pseudomonas aeruginosa ATCC® 27853™* and Klebsiella pneumoniae ATCC® 33495™* were 7.8, 1.9, 3.9 and 1.9 µg/ml, respectively. The in-vitro cytotoxicity on human lung fibroblast cells demonstrated that green synthesized silver nanoparticles were nontoxic at the MIC. The in-vivo study revealed that AgNPs loaded hydrogel presented an improved antibacterial efficacy and wound healing effect, with normal skin appearance when compared with silver sulfadiazine cream (Dermazin®). The present investigation suggests that green synthesized AgNPs silver are going to be a promising therapeutic nontoxic antibacterial agent against MDR bacteria with improved wound healing efficacy.