In this paper, Lipozyme TLIM-catalyzed synthesis of ethyl cinnamate through esterification of cinnamic acid with ethanol was studied. In order to increase the yield of ethyl cinnamate, several media, including acetone, isooctane, DMSO and solvent-free medium, were investigated in this reaction. The reaction showed a high yield by using isooctane as reaction medium, which was found to be much higher than the yields reported previously. Furthermore, several parameters such as shaking rate, water activity, reaction temperature, substrate molar ratio and enzyme loading had important influences on this reaction. For instance, when temperature increased from 10 to 50 °C, the initial reaction rate increased by 18 times and the yield of ethyl cinnamate increased by 6.2 times. Under the optimum conditions, lipase-catalyzed synthesis of ethyl cinnamate gave a maximum yield of 99%, which was of general interest for developing industrial processes for the preparation of ethyl cinnamate.

In order to obtain a deep insight into the effects of spacer arms on performing CB modification and dye-affinity adsorption, poly(methyl methacrylate) (PMMA) magnetic microspheres were prepared and modified respectively with poly(ethylene glycol) (PEG), poly(vinyl alcohol) (PVA) and ethylenediamine (EDA) as spacer arms. Then, an affinity dye-ligand, Cibacron Blue F3GA (CB), was coupled with these spacer arms to synthesize three kinds of CB-attached magnetic microsphere including CB-PEG-PMMA, CB-PVA-PMMA and CB-EDA-PMMA. CB density of the resulting microspheres was determined to be 138.1μmol/g for CB-PEG-PMMA, 209.7μmol/g for CB-PVA-PMMA, and 266.0μmol/g for CB-EDA-PMMA, respectively. The affinity adsorption performances of the resulting microspheres were evaluated using bovine serum albumin (BSA). The results showed that the adsorption capacity of BSA increased with the increase in CB density, and CB-EDA-PMMA microspheres exhibited the highest adsorption capacity. Furthermore, the effects of pH, BSA concentration and ionic strength on BSA adsorption were investigated and the maximum adsorption capacity was found to be 114.0mg/g CB-EDA-PMMA microspheres. Moreover, the reusability of the microspheres was also studied.

In this study, lipase catalysis was successfully applied in synthesis of benzyl cinnamate through esterification of cinnamic acid with benzyl alcohol. Lipozyme TLIM was found to be more efficient for catalyzing this reaction than Novozym 435. In order to increase the yield of benzyl cinnamate, several media, including acetone, trichloromethane, methylbenzene, and isooctane, were used in this reaction. The reaction showed a high yield using isooctane as medium. Furthermore, the effects of several parameters such as water activity, reaction temperature, etc, on this reaction were analyzed. It was pointed out that too much benzyl alcohol would inhibit lipase activity. Under the optimum conditions, lipase-catalyzed synthesis of benzyl cinnamate gave a maximum yield of 97.3%. Besides, reusable experiment of enzyme demonstrated that Lipozyme TLIM retained 63% of its initial activity after three cycles. These results were of general interest for developing industrial processes for the preparation of benzyl cinnamate.

Objective To analyze the transcription level of new tumor suppressor gene SLC5A8 mRNA in colorectal cancer tissues.Methods Collected specimens of 23 cases with colorectal cancer and cut out carcinoma tissues and Pericarcinomatous tissue respectively,then used real time fluorescent quantitative PCR (RT-qPCR)to detect the transcription level of gene SLC5A8 mRNA,and the results of carcinoma tissues and pericarcinomatous tissues were analyzed by t test.Results The transcription level of new tumor suppressor gene SLC5A8 mRNA in colorectal cancer tissues is significantly lower than pericarcinomatous tissue (P =0.002).Conclusion The expression of gene SLC5A8 in colorectal cancer tissues is declining or missing,suggesting it has a certain relationship with the incidence of colorectal cancer.

Poly(styrene-acrylic acid) magnetic microspheres with an average diameter of 2 μm were successfully prepared and used as carriers to immobilize lipase. Lipase immobilized on microspheres with no spacer arm exhibited low activities, which were attributed to steric hindrance on the lipase conformation. To avoid steric effects, ethylenediamine and poly(ethylene glycol) (PEG) 400/800/4000 were utilized as spacer arms to bind the lipase to the microspheres. The immobilized lipase activities were improved using PEG 800/4000 as a spacer arm. Furthermore, the influence of enzyme loading on lipase activity was investigated, and the results indicated that enzyme overloading could exert steric effect on lipase activity. The degree of PEG modification was demonstrated to affect lipase activity because excess PEG on the surface of microspheres could interact with lipase due to its mobility, consequently reducing lipase activity.

Current research suggests that SLC5A8 is a new candidate tumor-suppressor gene whose expression is reduced or deficient in human thyroid cancer,esophageal cancer,gastric cancer,colon cancer and acute myeloid leukemia.The gene is in human chromosomes 12q13-23,and encoding proteins that belongs to the members of the family of sodium/glucose transporters.It is sodium-coupled carrier that transfer short chain fatty acid,lactic acid,nicotinic acid and iodide.The exon 1 of GPG island methylation and histone acetylation can make SLC5A8 gene express silenced and promote the occurrence of tumor.of all transporter substrates of SLC5A8 expresses,butyrate,propionate and pyruvate function as histone deacetylase inhibitors and can be mediated apoptosis of many kinds of tumor cells,which may be the mechanism of inhibiting tumor.