一株产蓝色素放线菌的筛选及发酵研究

从土壤中筛选到1株蓝色素产量较高的放线菌,命名为Cya-5.对蓝色素发酵条件进行研究,结果显示发酵培养基的配方为甘油20 g/L、KNO31 g/L,K2HPO40.5 g/L,MgSO4.7H2O 0.5 g/L,FeSO4.7H2O 0.01 g/L,NaCl 0.5 g/L,pH=8.5,装液量为100 mL/250 mL三角瓶、30℃发酵96 h,发酵液的A590总值达到12.02.利用碱沉法提取发酵液中的色素物质,粗提物色价可达到45.8.

Lipase Immobilization onto the Surface of PGMA-b-PDMAEMA-grafted Magnetic Nanoparticles Prepared via Atom Transfer Radical Polymerization

A block copolymer of 2-dimethylaminoethyl methacrylate(DMAEMA) and glycidyl methacrylate(GMA)was grafted onto the surface of magnetic nanoparticles(Fe3O4) via atom transfer radical polymerization.The resultant PGMA-b-PDMAEMA-grafted-Fe3O4 magnetic nanoparticles with amino and epoxy groups were characterized by Fourier transform infrared spectroscopy, powder X-ray diffraction, thermo-gravimetric analysis, and scanning electron microscopy. Lipase from Burkholderia cepacia was successfully immobilized onto the magnetic nanoparticles by physical adsorption and covalent bonding. The immobilization capacity of the magnetic particles is 0.5 mg lipase per mg support, with an activity recovery of up to 43.1% under the optimum immobilization condition. Biochemical characterization shows that the immobilized lipase exhibits improved thermal stability, good tolerance to organic solvents with high lg P, and higher p H stability than the free lipase at p H 9.0. After six consecutive cycles, the residual activity of the immobilized lipase is still over55% of its initial activity.

多发性骨髓瘤患者国际分期体系分期的影响因素

目的 探讨多发性骨髓瘤(MM)患者国际分期体系(ISS)分期的影响因素。方法 选择2018年7月至2020年12月信阳市妇幼保健院收治的80例MM患者,根据ISS分期标准将MM患者分为:Ⅰ期14例,Ⅱ期30例,Ⅲ期36例。比较不同分期患者的一般资料、血清维生素D、生长分化因子15(GDF-15)、白细胞介素-6(IL-6)水平,并对影响ISS分期的因素进行logistic回归分析。结果 不同病情程度患者居住地、体能情况、收入状况、婚姻状况、高血压史、糖尿病史及受教育情况比较,差异无统计学意义(P>0.05),不同分期MM患者性别、年龄比较,差异有统计学意义(P<0.05),Ⅲ期男性、>50岁患者占比高于Ⅰ、Ⅱ期(P<0.05);与Ⅰ期MM患者比较,Ⅱ期和Ⅲ期MM患者血清维生素D水平降低,GDF-1及IL-6水平升高(P<0.05),与Ⅱ期MM患者比较,Ⅲ期MM患者血清维生素D水平降低,GDF-15、IL-6水平升高(P<0.05);将性别、年龄、血清维生素D、GDF-15、IL-6纳入多因素logistic回归分析,结果显示性别、年龄、血清维生素D、GDF-15、IL-6是MM患者ISS分期的独立危险因素(OR=3.540,95%CI:1.556~8.052;OR=4.100,95%CI:1.802~9.327;OR=3.658,95%CI:1.608~8.322;OR=3.274,95%CI:1.439~7.448;OR=3.850,95%CI:1.692~8.757,P<0.05)。结论 性别、年龄、血清维生素D、GDF-15及IL-6水平是MM患者ISS分期的独立危险因素,血清维生素D、GDF-15、IL-6能够作为MM疾病分期的观察指标。