Study On Enzyme-mimic Peptide Assembly To Degrade Phthalate Ester Di(2-ethylhexyl)-phthalate

Plasticizer,in nature it is a kind of polymer additives,mainly used in plastic processing,its role is reinforced plastic flexible and patience.But at present many manufacturers in order to packaging material durability,add to the plasticizer in food packaging materials.This leads that the plasticizer enter into human body through food,long time use of packaged food will make the plasticizer concentrates in the human body,thus seriously affect human health.So the study of a substance capable of degrading such plasticizers is very necessary and meaningful.The purpose of this study is to explore a material that can degrade plasticizers,which is a protein that simulates natural esterase-cutinase.First of all,the design of small peptide sequence was the most critical part in the whole experiment process,in the process of simulating natural amino acid sequence of esterase,with the active site,and combined with the vector of amino acids for the formation of a simulated natural esterase degradation of small peptide sequence,mainly by gas chromatography-mass spectrometry(GC-MS)for qualitative analysis,to determine the degradation product.Based on the design of small peptides,also were characterized by transmission electron microscopy,round two color spectrum,the main morphological changes of small peptides.Next,we need explore the optimum conditions of various kinds of small peptide degradation of plasticizer DEHP.The main factors including temperature,reaction time,pH,concentration of zinc ions and small peptide concentration.The experiment showed that the optimum conditions was 40-50 ?,the reaction time was 48 h,pH 8.0-9.0,zinc ion concentration was 10 mM,the concentration of small peptides was 2.5 mM.After the small peptide degradation reaction,we also made the small peptide reacted by transmission electron microscope and round two color spectrum were characterized on the amino acid properties change.The research results showed that the degradation reaction did not destroy the properties of small peptide itself,it also showed the stability of the design of small peptides.At the same time,the detection pack up boxes used in the real life of the actual sample experiments showed that the amounts of raw materials in the box under the action of small peptides,the plasticizer content decreased,and the product of adjacent benzene two formic acid(PA).According to the simulation of natural esterase,design of small peptide sequence detection,the optimum conditions of research and actual samples,including the characterization of TEM and circular dichroism spectra,it can be found that the small peptide sequence designed in this study could degrade the plasticizer very stable,and the product was non-toxic,did not cause harm to the environment,this for the future study on degradation of plasticizer,provided a new way to reduce the harm to the environment of the plasticizer.