Synthesis of curcumin quantum dots and their antimicrobial activity on necrotizing fasciitis causing bacteria

Necrotizing fasciitis is defined as an infection of soft tissue such as dermis, subcutaneous tissue, or muscle that linked with necrotizing changes. Curcumin is well known for its excellent antioxidant, anti carcinogenic and anti-inflammatory activities. In this study, we aimed to synthesize curcumin quantum dots by using a combination of mechanical and ultrasonic milling techniques. Besides, the antimicrobial efficacy of the quantum dots was also tested on necrotizing fasciitis causing bacteria. Electron micrograph of curcumin quantum dots showed that the particles were irregular in shape, with an average size of 13.7 nm. Curcumin quantum dots possess a zeta potential of -13.3 mV based on zeta potential analysis. The antimicrobial activity was tested on 7 test bacteria. Curcumin quantum dots exhibited wide spectrum antibacterial activity, as the particles inhibit both Gram-positive and Gram-negative bacteria. The minimal inhibitory concentration (MIC) of curcumin quantum dots ranged from 7.8 to 62.5 mu g/ml, which indicates different susceptibility of test bacteria to curcumin quantum dots. The lowest MIC was recorded on Streptococcus sp. and Klebsiella pneumoniae. The antibacterial activity of curcumin quantum dots was bacteriostatic as high minimal bactericidal concentrations (MBC) were reported. On growth profile analysis, curcumin quantum dots displayed concentration-dependent killing capacity on Streptococcus sp. and K. pneumoniae. At the concentration of MBC, 99.9% killing of bacterial cells was observed throughout the experimental period. A significantly lower bacterial growth was observed relative to control. The synthesized quantum dots exhibited broad-spectrum antibacterial activity, particularly on Streptococcus sp. and K. pneumoniae. The antibacterial activity was bacteriostatic. Further investigations should be conducted to evaluate the antibacterial efficiency of curcumin quantum dots by using in vivo animal models. (c) 2019 Elsevier Ltd. All rights reserved. Selection and Peer-review under responsibility of the scientific committee of the 4th International Conference on Green Chemical Engineering and Technology: Materials Science.