THE DYNAMIC PROPERTIES FOR THE PROTEIN MOLECULAR SYSTEM

In this paper, a new theory for the dynamic properties of protein molecular system have been proposed by means of the analysis of the characteristics of the collective excitations generated under the localized fluctuation and the deformation of structure of the protein. Some new results obtained from this study show that the Davydov theory is an approximate and disadvantegeous theory.

Low-temperature combined with high-humidity thawing improves the water-holding capacity and biochemical properties of Portunus trituberculatus protein

This study compared the effects of conventional thawing methods(water immersion thawing(WIT,(25±1)℃),natural air thawing(AT,(25±1)℃,relative humidity(RH(65±2)per cent),refrigerator thawing(RT,4℃,RH(80±2)per cent)and low-temperature(LT)combined with high-humidity thawing LT,-1℃to 1℃(LT-1-1),2-4℃(LT2-4),5-7℃(LT5-7)and 8-10℃(LT8-10),RH>95 per cent)on the water-holding capacity,lipid oxidation and biochemical properties of Portunus trituberculatus(P.trituberculatus)myofibrillar protein.The results showed that WIT and AT significantly decreased the water-holding capacity while dramatically increasing lipid oxidation,protein oxidation and degeneration,resulting in serious P.trituberculatus quality deterioration.High humidity was beneficial for P.trituberculatus\.ha\A/\ng.The thawing time of P.trituberculatus under the conditions of LT2-4 was only 39.39 per cent of that of conventional air thawing at 4℃(RT),and the LT2-4 samples not only maintained better water-holding capacity but also had an obviously reduced degree of lipid oxidation,protein oxidation and denaturation.Thawed samples LT2-4 and LT5-7 provided better maintenance of P.trituberculatus quality than the LT-1-1 and LT8-10 samples.The best quality was exhibited after thawing at 2-4℃.The levels of thiobarbituric acid reacting substances,carbonyl content and surface hydrophobicity observably decreased in these samples,while the total sulfhydryl contents dramatically increased compared to those of conventionally thawed samples,indicating lower lipid oxidation and protein oxidation.Moreover,the Ca2+-ATPase activity of the sample thawed at 2-4℃(2.06 μmol Pi/mg prot/h)was markedly higher than that of samples subjected to WIT and AT.The product qualities observed after thawing at-1℃to 1℃,5-7℃and 8-10℃under LT were comparable to that observed by RT.Considering its thawing efficiency and product quality,LT is a suitable method for the thawing of P.trituberculatus,and the ideal thawing conditions were LT at 2-4℃.

The preparation of a novel polydopamine-graft-poly(2-methyl-2-oxazoline) protein-resistant coating and its applications in protein separation

A novel polydopamine-graft-poly（2-methyl-2-oxazoline） （PDA-g-PMOXA） coating was prepared by immobilizing poly（2-methyl-2-oxazoline） （PMOXA） onto material surfaces through polydopamine （PDA） anchored coating for the first time. And then, the chemical composition, hydrophilicity, and protein-resistant properties of the PDA-g-PMOXA coating were studied using X-ray photoelectron spectroscopy （XPS）, contact angel （CA） test, surface plasmon resonance （SPR）, and quartz crystal microbalance with dissipation （QCM-D） measurement. Finally, the coating was applied to the capillary inner surface for protein separation by capillary electrophoresis （CE）.

In situ synthesis of magnetic mesoporous silica via sol-gel process coupled with precipitation and oxidation

A novel method was proposed for the in situ synthesis of magnetite-containing mesoporous silica SBA- 16 via a sol-gel process coupled with precipitation and oxidation. The effect of the added amounts of reactants on the mesostructural and magnetic properties of the magnetic mesoporous silica was inves- tigated, It was determined that the synthesized magnetic mesoporous silica with a total pore volume of 0.64-0.96 cm3/g and an average pore diameter of 4.0-14,9 nm had a relatively high saturation mag- netization value （1.11-5.77 emu/g） and a large surface area （258-747 m2/g）, Lysozyme was chosen as a model protein to test the performance of the magnetic mesoporous silica as a protein adsorbent, The high adsorption capacity （up to 212 mg/g） suggested a promising future as bimolecular hosts for the magnetic mesoporous silica.