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61.
用超滤法将蛹虫草(Cordyceps militaris)子实体水提物分为<10 kDa(PW1)、10~100 kDa(PW2)、100~300 kDa(PW3)、300~750 kDa(PW4)和>750 kDa(PW5)5个部分,并测定了这5部分的总糖含量、单糖组成及其对巨噬细胞释放NO产量的影响.结果表明,蛹虫草粗提物总得率(PW1~PW5之和)为38.35%,其中PW1得率最高(36.482%),其次是PW2(1.822%),PW3~PW5的得率都很低;各部分的总糖含量都较高(45.70%~60.48%).单糖组成分析表明,各部分的多糖分别由3~6种单糖组成,其中甘露糖、葡萄糖、半乳糖为主要单糖.PW2~PW5均具有刺激巨噬细胞释放NO的活性,且随着浓度的增加活性增强.  相似文献   
62.
本文阐述了中空纤维超滤膜澄清果汁时浓差极化现象的产生原理,并从正反向进料,加压及反冲等方面分析了对策 。  相似文献   
63.
On account of the characteristics of water in Taihu during high algal period, the pilot investigation was conducted with the combination of ultrafiltration membrane with coagulation, pre oxidation technology or adsorption technology. The results show that the quality of influent water from the three combination processes: coagulation precipitation ultrafiltration membrane, potassium permanganate coagulation precipitation ultrafiltration membrane, potassium permanganate coagulation precipitation power activated carbon ultrafiltration membrane are preferred, with turbidity lower than 0.1 NTU, algae control in the number of 2.5 × 104/L, and other measured targets meet the drinking water standards (GB 5749—2006). The organic matter of high algal water mainly includes hydrophobic organic compounds which are major factors leading to membrane fouling. The effective pre treatment before ultrafiltration membrane can prevent hydrophobic organic compounding into the membrane pore, which will effectively ease the membrane fouling during the high algal period.  相似文献   
64.
Apple Pectin Behavior Separated by Ultrafiltration   总被引:1,自引:0,他引:1  
Separation conditions of ultrafiltration for apple pectin, weights and their structures and properties are studied and relations between apple pectin with different relative molecular Five kinds of ultrafiltration membranes with different molecular weight cut-offs are used to separate apple pectin. FT-IR and HPGC are used individually to determine the structures and monosaccharide composition of apple pectin with different relative molecular weights. In the case of transmembrane pressure difference of 0.08 MPa, material concentration of 1 g·L^-1, and temperature of 50℃, 6 kinds of apple pectins with different molecular weights have been obtained. Molecular weight of apple pectin is correspondingly related to its physicochemical properties. The galacturonic acid contents and esterification and gelatination degrees increase relatively with an increase in molecular weight, and the monosaccharide composition relatively increase much more. And at the same time, the ultrafiltration has a better role to play in decoloring apple pectin solution. Accordingly, this research can be used as a new method for in-depth exploration of apple pectin.  相似文献   
65.
[目的]研究荨麻中3,4-二香草基四氢呋喃的提取以及纯化,为进一步研究荨麻中3,4-二香草基四氢呋喃的作用机制奠定基础。[方法]采用醇水溶液回流提取,研究大孔吸附树脂吸附和分离狭叶荨麻提取液中3,4-二香草基四氢呋喃的方法和条件,并采用超滤膜纯化技术对其进行纯化。[结果]X-5大孔吸附树脂对3,4-二香草基四氢呋喃有较好的吸附能力;乙醇浓度为60%时解吸效果最好,解析液浓缩,超滤膜纯化重结晶后,荨麻中3,4-二香草基四氢呋喃纯度可达85.3%。[结论]采用X-5大孔吸附树脂以及超滤膜纯化技术可有效地提取荨麻中3,4-二香草基四氢呋喃,为今后荨麻中有效成分的研究与开发应用提供理论依据。  相似文献   
66.
用溶剂抽提法分离出含钠盐及低相对分子质量(Mr)物质的麦草常温碱提取水溶性木质素-碳水化合物复合体(LCC)级分,采用中空纤维管式超滤技术定量去除LCC中钠盐及低Mr(<1000)物质等杂质.研究结果表明,在超滤压力为0.10 MPa、超滤浓度为0.5%(以质量分数计)的条件下,水溶性LCC经10次循环超滤后,其中钠盐及低Mr物质得到了有效去除,分离得到高得率、高纯度、富含碳水化合物的水溶性LCC级分.  相似文献   
67.
To further utilize bioactive substance such as bovine colostrum sIgA and IgG, sIgA and IgG were isolated and purified simultaneously by salting out, ultrafiltration and gel chromatography, etc. The analysis of results were showed quantitatively by nonhydrogenized SDS-PAGE, and quanlities of sIgA and IgG were respectively detected by Western Blot. The results showed that the purity and yield of bovine colostrum sIgA were 85.3% and 42.8%, respectively, while the purity and yield of bovine colostrum IgG were respectively 97.2% and 64.4%. This preparative method provides theoretical and experimental foundation for sIgA industrial production.  相似文献   
68.
确定C型产气英膜梭菌合成培养基使用参数及建立配套的毒素浓缩工艺。比较不同pH值、灭菌温度、配制用水的合成培养基及其不同培养时间和温度下培养产气荚膜梭菌CVCC60102株的毒力;按毒素的分子量及超滤膜的截留分子量设计并比较2种不同浓缩工艺的毒素收获率及透出液的毒力。结果表明,pH值为8.0~8.4、灭菌方式为116℃30min、配制用水为去离子水时产毒最佳,毒力达到500—1000MLD/mL;合成培养基培养产气英膜梭菌CVCC60102株18h后毒力达500—1000MLD/mL,随着时间的延长,毒力不再增强;培养温度为36℃或37℃时,产毒效果最佳;不同截留分子量的超滤膜浓缩,10ku截留分子量的收获率为68%,其透出液静脉接种0.2mL,小鼠2/2死亡;而8ku收获率达80%,其透出液静脉接种0.2mL,小鼠0/2死亡。因此8ku截留分子量膜包适宜对C型菌培养毒素的浓缩。上述结果为C型产气荚膜梭菌合成培养基的应用提供了数据支撑。  相似文献   
69.
通过中空纤维超滤法及亲和凝胶层析法对鸡蛋清中溶菌酶进行提取精制,结果表明蛋清溶菌酶的最佳超滤提取工艺为:连续稀释4倍、超滤温度35℃,料液pH值8.5,进样压力0.08 MPa,再经超滤浓缩处理,酶活得率为131.93%,溶菌酶透过率为73.57%,样品液的酶活约为4 700 U/mL。经过亲和凝胶层析的进一步纯化及真空冷冻干燥,最终蛋清溶菌酶冻干粉的酶活为18 500 U/mg,蛋清溶菌酶的酶活得率为180.83%。  相似文献   
70.
Peptones were obtained from cod stomachs as a by-product during enzyme production. Minced cod stomachs were autolyzed after acidification with either formic or phosphoric acid, and low molecular weight (< 10 kDa) peptones were recovered. When formic acid was used, an acid peptone was obtained, whereas phosphoric acid was removed from the peptone after calcium precipitation. The peptones were compared with Proteose Peptone (Difco, Detroit, MI, USA) as nitrogen sources in growth media for three marine bacteria. Two fish pathogens—Vibrio anguillarum and Aeromonas salmonicida—grew equally well or better on the cod stomach peptones, whereas a probiotic lactic acid bacteria (Carnobacterium divergens), isolated from salmon intestines, grew much better on the cod stomach peptones than on Proteose Peptone.  相似文献   
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