Research On The Antimicrobe Property Of LDHs-lysozyme Complex

Microbes play an important function in our life and have a positive role in food fermentation,energy and chemical industry.However some pathogenic bacteria are responsible for many infectious diseases,food safety and ecological pollution.Layered double hydroxide(LDH)is a kind of natural two-dimension material which has been widely used in biology,medicine,catalysis and chemical industry.Hydrotalcite and object drugs are used to prepare supramolecular composite materials,which improves the stability and efficiency of the drug.Lysozyme is a green natural antibacterial agent,which has the function of antibacterial,anti-virus and promoting the repair of the body.It is also not easy to develop resistance.However,the application of lysozyme has been restricted,because the activity of enzyme protein is easily influenced by environmental factors,such as temperature and pH.As a good carrier,hydrotalcite can effectively guarantee the activity of lysozyme and obtain compound antibacterial materials with antibacterial properties.The research content of this thesis mainly includes the following contents:1.The preparation and antimicrobe performance of binary and ternary hydrotalcite-lysozyme complex.We adjust the metal cations of LDH to tune the surface morphology of hydrotalcite.We find that binary and ternary hydrotalcite show different adhensive ability to microbes,because of the difference surface mophology.The ternary hydrotalcite,which has bloom flower surface,can load more lysozyme,and has better antibacterial property than the other binary LDHs.In this work,lysozyme is loaded on MgAl-LDH?ZnAl-LDH and ZnMgAl-LDH,Their structure and morphology are characterized.Their antimicrobial properties are tested in the culture medium of bacteria.And the biological toxicity in vitro and in vivo is evaluated.Flower-like surface structure of ZnMgAl-LDH can increase the payload of lysozyme.lysozyme@ZnMgAl-LDH has good antibacterial properties for gram-negative bacteria(E.coli)and gram-positive bacteria(S.aureus).And it also can promote wound healing.The rough surface of ZnMgAl-LDH can adsorb more bacteria,so the antibacterial activity of lyso@ ZnMgAl-LDH is better than binary hydrotalcite-Iysozyme complex.In the experiment of wound healing in mice,hydrotalcite-lysozyme complex has a significant effect on inhibiting bacterial growth and promoting wound healing.lyso @LDHs is doped into the polymer film by the way of light curing.The polymer film with lyso@LDHs has obvious antibacterial property,which provided more possibilities for subsequent applications.2.The research on inhibiting multi-resistant bacteria activity of ternary hydrotalcite-lysozyme complex.We researched the antimicrobial activity of ternary hydrotalcite-lysozyme complex for multi-resistant bacteria.We synthesize lyso@ZnMgAl-LDH,lyso@NiZnAl-LDH,lyso@CuZnAl-LDH and lyso@CoZnAl-LDH,then characterize the structure of the four materials.We compare the antibacterial activity of these ternary LDHs complex for the standard bacteria.We find that lyso@NiZnAl-LDH shows prominent antibacterials activity for multidrug resistant bacteria.NiZnAl-LDH can carry a large amount of lysozyme on its bract structure which has good inhibiting property for CR E.coli and MR S.aureus(resistant to penicillin,chloramphenicol,cephalosporin,methoxylin,etc.).