Preparation And Physicochemical Properties Of Chitosan Loaded With Lysozyme

Chitosan is the only basic aminopolysaccharide present in the polysaccharides of the natural world.It has non-toxicity,biodegradability,strong adsorptivity and biocompatibility.It has been widely used in food,biology,materials science and drug release.In the field.In this paper,chitosan was selected as the raw material,and it was degraded.The lysozyme was encapsulated by ion-crosslinking to form microspheres.Then,the microspheres were made by adding nano-cellulose and their properties were studied.Low molecular masschitosan with high degree of deacetylationhas excellent bioactivity including antioxidant,antibacterial and encapsulation properties.In this work,to reduce the MM of chitosan,microwave-assisted heating treatment??????conditions were investigated using three factors at three levels Box-Behnken design?BBD?.Microwave heatingtime,H₂O₂ concentration and solid-toliquid ratio significantly affected the DDA and MM of chitosan.The antibacterial activities of chitosan before and after degradation were investigated based on minimum inhibitory concentration?MIC?and minimum bactericidal concentration?MBC?.The results showed that a second-order polynomial equation fitted the observed values using multiple regression analysis and had a high coefficient of determination?R₂=0.9591and 0.9161 for the DDA and MM of chitosan,respectively?.An optimisation study was performed using Derringer's desirability function methodology,and the optimal conditions were 80-s MH time,1.5%H₂O₂ concentration and 1:40 solid-to-liquid ratio.The MIC and MBC of chitosan before and after degradation against Escherichia coli and Salmonella typhimurium were 0.031 and 0.063 mg mL 1,and 0.25 and 0.125 mg mL 1,respectively.The optimised DDA and MM of chitosan were 90.58 2.04%and124.2514.36 kDa,respectively,which significantly reduces the use of oxidant reagent.Nanotechnology is widely used in many fields,such as food,medicine,biology,material science etc.Its all because nanoparticles has high sensitivity,high encapsulation efficiency,small size effect and other characteristics.Under the optimized conditions,we usedpoly ionic crosslinking the chitosan and sodium phosphate,meanwhile,the lysozyme acted as an antibacterial agent,we prepared four type of nanoparticles,high molecular weight beta molecular chitosan nanoparticles and the same size of low molecular weight,high molecular weight beta chitosan nanoparticles loaded with lysozyme and the same size of low molecular weight size,and its slow-release property can be easily mesured.The CS was depolymerized for obtaining CSNPs at<200 nm.Lysozyme complex loaded small diameter CS NPs were further prepared with a lysozyme complex encapsulation efficacy of 70.90%,average particle size of 186.6 nm,and Zeta-potential of 10.83 mV.The results showed that the low molecular weight chitosan nanoparticles and the high molecular weight chitosan nanoparticles had almost fully overlap with the absorption wavelength,which means the absorption wavelength will not affect by molecular weight.It was found that the encapsulation efficiency of low molecular weight chitosan was higher than that of high molecular weight,and the concentration of lysozyme in 1.5mg/ml was the best.The in vitro release study conducted at pH 7.4 showed that the lysozyme complex loaded small diameter CS NPs sustained the release of the lysozyme complex over 2.5 h.This study suggested that lysozyme complex loaded small diameter CS NPs can be used as an antioxidants delivery system for food and other applications.Now people's lives become better day by day,and accompanied by a significant increase in people's living standards,is now everyone's concern about the safety of food,food antibacterial in this era will have a very big significance.Nano-cellulose film is currently used in fabrics;but it's rarely used in food.Based on some existing research results,this paper su MM arizes the research on the antibacterial effect of CNC nanoparticles.Antibacterial nano-film played an important role on antibacterial of all types of food.The depolymerization of-chitosan and the conditions of nanoparticles were optimized.The chitosan nanoparticles loaded with different molecular weight lysozyme complexes were prepared and then the encapsulation efficiency was determined.Prepare of nano-fiber crystals after the preparation of chitosan nanoparticles of the CNC antibacterial film.The lysozyme was loaded into chitosan CNC nanoparticles with different particle sizes and the growth curve of the measuring instrument was measured.Finally,the inhibition zone of-chitosan CNC nanoparticles with different molecular weight of lysozyme was determined.The results showed that the lysozyme concentration was the best at 1.5mg/ml,and the antimicrobial effect of lysozyme loaded small molecular weight chitosan CNC nanoparticles was significantly better than that of lysozyme loaded with high molecular weight chitosan.particle.