Carboxymethyl Chitosan Research Paper

2058 Words9 Pages

Effect of γ-rays on carboxymethyl chitosan for use as antioxidant and preservative coating for peach fruit
Ahmed M. Elbarbarya* and Tahia B. Mostafab a Polymer Chemistry department, National Center for Radiation Research and Technology, Nasr City, Cairo, Egypt b College of Women, Ain Shams University, Cairo, Egypt
Abstract
Carboxymethyl chitosan (CMCS) was synthesized by alkylation of chitosan using monochloroacetic acid and characterized by FTIR and 1H-NMR spectroscopy. Different molecular weights (Mw) of CMCS were prepared by radiation degradation of CMCS in the solution form at different irradiation doses. The structural changes and Mw of degraded CMCS were confirmed by UV-Vis, FTIR and GPC. The antioxidant activity of CMCS were evaluated …show more content…

Briefly, 1.5 ml of DPPH solution (0.1 mM, in 95 % ethanol) was incubated with different concentrations of unirradiated and irradiated CMCS solutions. The reaction mixture was shaken well and incubated for 15 min at room temperature and the absorbance of the resulting solution was read at 517 nm against a blank (control). Ascorbic acid was used for comparison as antioxidant materials. The radical scavenging effect was measured as a decrease in the absorbance of DPPH and can be calculated using the following …show more content…

unirradiated CMCS and irradiated CMCS were screened in vitro for their antibactericidal activity (against Gram positive bacteria S. aureus and Gram negative bacteria E. coli) and antifungal activity (against Aspergillas flavus and Candida albicans). In this method, a standard 5 mm diameter sterilized filter paper disc impregnated with samples (1 mg/ml of DMF) was placed on an agar plate seeded with the test organism. The agar plates were then incubated for 24 h at 37 °C for bacteria and 28 °C for fungi. After incubation, the interrupted growth zone (zone of inhibition) around the test material was measured (mm/mg) and used as quantitative indicator of antibacterial and antifungal effectiveness of CMCS. The values obtained were the average of 5 measurements on the same plate at different zones.
2.8. Data analysis
All statistical analysis was performed with SPSS (SPSS Inc., Chicago, IL, USA). Differences at ρ Society, 70, 383-386.
Ying, G.-q, Xiong, W.-y, Wang, H., Sun, Y., & Liu H.-Z. (2011). Preparation, water solubility and antioxidant activity of branched chain chitosan derivatives. Carbohydrate Polymers, 83, 1787–1796.
Zhou, T., Schneider, K. E., & Li, X. Z. (2008). Development of biocontrol agents from food microbial isolates for controlling post-harvest peach brown rot caused by Monilinia fructicola. International Journal of Food Microbiology, 126,

More about Carboxymethyl Chitosan Research Paper

Open Document