Biocatalysis Nitration Reaction Of Unsaturated Fatty Acid

Biocatalysis has become ideal catalyst of green chemical synthesis for its advantages of high efficiency, high specificity and less environmental pollution. However, the application of natural enzyme is limited because of its low catalytic activity and stability in conditions of industrial. Nanotechnology provides new possibilities for constructing efficient enzyme catalyst. How to produce nanoenzyme catalyst that has high catalytic activity and high stability through a simple, efficient, low cost method, and make its application in chemical synthesis are the key of issues.This paper studied a novel method to synthesis a soybean peroxidase-inorganic hybrid nanoflower by using soybean peroxidase(SBP). We also explored the influence of nanoflower immobilized enzyme catalysis on the generation of nitro oleic acid and compared with the synthesis of nitro oleic acid using chemical method. The conclusions are as follows :(1) Taking soybean hulls as raw materials, and the extraction and preliminary purification of soybean peroxidase were studied. We also studied the single factor experiment, the orthogonal experiment of enzyme extraction, then obtained the optimum extraction conditions of enzyme. By using the method of ammonium sulfate precipitation and acetone fractional precipitation, Soybean peroxidase was purified. The results showed that the enzyme optimum extraction condition: the material liquid ratio was 1:8, extraction temperature was 35 C, extration time was 18 h; ammonium sulfate precipitation lower saturation was 30 %, upper limit of saturation was 80 %; acetone precipitation lower volume multiple was 0.4, upper volume was 1.2.(2) We studied a novel method to synthesis a hierarchical flowerlike spherical structure with hundreds of nanopetals by using SBP as the organic component and Cu3(PO4)2·3H2O as the inorganic component. SEM and TEM image showed the morphology of the nanoflower, the effect of time and initial enzyme concentration on the structure were also studied. The structure of the hybrid nanoflowers was confirmed by FT-IR, XRD and EDS. Compared with the free SBP in solution, the enzymatic activity of SBP embedded in hybrid naonflowers exhibited an enhanced enzymatic activity(446 %). In cycle analysis, the hybrid nanoflowers also exhibited excellent reusability and reproducibility, it still maintain 80 % activity after 5 cycles.(3) The oleic acid was treated as the main object of the research. We have synthesized nitro oleic acid by chemical and biological methods in this part. After separation and purification, the products were characterized by IR, NMR and LC-MS techniques. We studied the effects of nanoflower immobilized enzyme to the synthesis of nitro oleic acid. The results showed that: the method of biological to synthesis nitro oleic acid inhibited the formation of by-product. Biological method was a new attempt to synthesis the nitro oleic acids, it laid the foundation of future research for the combination of immobilized enzyme and chemical synthesis.