| Popis: |
The metabolism of spoilage organism in the seafood is a major cause of fish spoilage. Lipid oxidation leads to production of intermediate peroxides causing bad odor and offflavour producing compounds. Hence, based on the hurdle technology method and applications of nanotechnology, the inhibitory effects of copper oxide nanoparticles coupled with vitamin-E (CuONPs+VE) was investigated with the aim of controlling the oxidative cell damage in seafood by estimating Reacting Oxygen Species (ROS) using 2’,7’- dichlorodihydrofluorescein diacetate (DCF) and preventing microbial spoilage by studying the cell viability using MTT assay in the present study. The MTT assay reveals that the CuONPs+VE inhibited the metabolic activity of spoilage bacteria which was confirmed from the inhibition percentage values against the test organisms. The CuONPs+VE exposed Escherichia coli reduced upto 86 ± 0.57% after enumerating the CFU in a Plate Count Agar media. Salmonella sp and Shigella sp exhibited 89 ± 1.04% and 85 ± 0.25% respectively. The qualitative inhibitory effect of Nanometal vitamin complex against three test bacteria, were evaluated by agar diffusion method. Among the four different concentrations of Nanometal vitamin complex, the higher concentration (4X – 40μg/ml) exhibited maximum inhibitory effects in terms of zone of clearance. Against Escherichia coli, 12.3 ± 1.25mm of inhibitory zones were found evident. Salmonella sp showed 15.6 ± 0.57mm of inhibitory zones and Shigella sp revealed the inhibition zone of about 16.6 ± 1.04mm. The anti-oxidative defence mechanisms operating in the cells for scavenging of ROS was performed using DCF. The cells which are pre-incubated with CuONPs+VE and then exposed to H2O2 show insignificant green emission indicating a clear advantage of the nanoparticle form of vitamin-E (CuONPs+VE) in preventing oxidative cell death. |
