Papers by Keyword: L-Lysine

Abstract: In this paper, spherical nanohydroxyapatite was synthesized by hydrothermal method. During the synthesizing process, different amount of L-lysine template was added with the hydrothermal temperature 185 °C and the time 25 h. The products were characterized by using FTIR, XRD and TEM. Results showed that the rod-like nanohydroxyapatite changed its granule morphology into spherical obviously after adding L-lysine. Spherical nanohydroxyapatite was synthesized with mean particle size about 25 nm.

Abstract: Methanol-water as solvent, transition metal Y-type zeolite as catalyst, L-lysine was synthesized laminin. Explores the methylation process factors, and the structure of the compound by IR, NMR and elemental analysis were characterized.

Abstract: Highly dispersed supported gold catalysts have been prepared by solution reduction method using L-lysine as protection agents, and their catalytic activity was evaluated by the liquid phase catalytic oxidation reaction of glucose to gluconic acid. The results suggested that the Au/ZrO₂ catalyst, exhibited high activity for the selective oxidation of glucose. At the reaction temperature of 323K, reaction time of 1h, with the NaCO₃-NaHCO₃ as buffer solution, the yield of gluconic acid was 100%.

Abstract: Glucose oxidase (GOD) and catalase (CAT) were co-immobilized on the cross-linked chitosan microsphere containing L-Lysine (CCL) by the method of absorption-crosslink, with cross-linking agent of glutaraldehyde. The optimized conditions of the co-immobilization are as follows: activity ratio of GOD and CAT is 0.78:1, concentration of glutaraldehyde is 0.17mmol/L, and the immobilizing process last for 3 hours. The enzyme activity of co-immobilized enzyme is 15.3U/mg and activity recovery is 50.1%. The half life is 231 days, 2.4 times of immobilized GOD.

Abstract: A L-lysine modified semi-crosslinked chitosan (LMCCT) beads was synthesized and demonstrated to be an excellent enzyme support by studying the enzymatic properties of glucose oxidases (GODs) immobilized on it. The prepared LMCCT beads have very larger BET specific surface ( 403 m²/g) and excellent chemical stability due to the semi-crosslinking of chitosan backbones. The insertion of the flexible L-lysine spacers between chitosan backbone and the active amino groups increases the activity of immobilized GODs (I-GODs) and improves the affinity of I-GODs towards the substrate, which was testified by the smaller Michaealis constant, K_m and larger reactive rate, V_m of I-GODs on LMCCT than that on crosslinked chitosan. Further studies of I-GOD activity at varied temperature and pH also indicated that I-GOD on LMCCT has an excellent stability.