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1.
为了寻找一种高效的奥利司他结晶工艺,对溶剂种类、晶种、反溶剂加入量、待结晶溶液浓度、搅拌转速和降温速度等因素进行了研究。通过静态结晶实验,确立了甲醇/水为最佳的结晶体系及其比例,加入晶种能明显提高奥利司他的析晶温度,提高产品含量和纯度。在此基础上,经正交试验设计L9(34),通过50 L结晶罐动态考察了各因素对奥利司他结晶产品含量和收率的影响,并进一步优化了加水方式。结果表明:按照2℃/h速率降温,初始奥利司他质量浓度为30 g/L,反溶剂水的加量为25%(体积分数),分2次加入,析晶前加入产品质量0.1%的晶种,搅拌转速250 r/min条件下,所得奥利司他晶体含量和收率最高。经高效液相色谱(HPLC)检测,奥利司他含量可达98.6%,收率可达85.3%。  相似文献   

2.
成熟欧李果肉中单宁提取条件的优化   总被引:3,自引:0,他引:3  
以成熟欧李为试验材料,乙醇、丙酮、二甲基甲酰胺为提取剂,采用L25(5^6)正交试验设计,从溶剂浓度、固液比、浸提时间、浸提温度等因素的不同水平对欧李果肉中单宁的提取条件进行了研究,结果表明:从欧李果肉中提取单宁的最佳条件为:以丙酮作提取剂,浓度60%,浸提时间4h,浸提温度30℃,固液比1:20;以乙醇作提取剂,浓度30%,浸提时间4h,浸提温度60℃,固液比1:30。  相似文献   

3.
采用大孔吸附树脂层析结合硅胶柱层析,对环孢菌素A的分离纯化进行研究,确定了最佳层析条件,建立了工业化制备环孢菌素A的工艺。大孔吸附树脂层析选用D101树脂作为吸附介质,提取液丙酮含量控制在50%,最大吸附量为35 mg/g湿树脂,洗脱剂选用丙酮;硅胶柱层析选用42~64μm硅胶作为层析介质,最优层析条件为柱床高径比10∶1,流动相配比V(石油醚)∶V(丙酮)=70∶30,流速80 mL/m in,环孢菌素A上样质量浓度100 g/L,硅胶层析平均收率为84.2%,环孢菌素A纯度可达到97%以上,整个工艺总收率为65%~70%。  相似文献   

4.
研究了提取溶剂、温度、时间、料液比4个因素对山葡萄籽中原花青素得率的影响。确定最佳提取工艺:以70%丙酮为提取荆,在60℃条件下,提取120min,料液比为1:7,原花青素的得率为2.31%  相似文献   

5.
本文通过超临界CO2提取芝麻油的均匀设计实验和微波和超声波诱导提取芝麻油的正交实验比较,考察影响提取的主要因素,寻求最佳萃取工艺。超临界CO2萃取最佳工艺条件为:压力32MPa,温度60℃,CO2流量31kg/h,萃取时问80min,得率46.39%;微波萃取最佳工艺条件为:溶剂为丙酮,物料与溶剂比例1:7,辐射时间7min,辐射功率810W,得率23.01%。超声波萃取最佳工艺条件为:物料与溶剂比例1:7,溶剂为石油醚,浸泡时间30h,得率23.99%。结果表明超临界CO2萃取芝麻油品质最好,而且萃取也最高,质量最稳定。  相似文献   

6.
探索利用超声波微波协同盐提湘莲蛋白质最佳提取条件。最佳工艺条件为超声波功率50w,微波功率600W,料液比1:12(g/mE)、38℃、0.15mol/LNaCl盐溶液提取15min,最佳提取率可达88.9%。以CO2为沉淀剂,乙醇为助溶剂,研究加压CO2和乙醇对蛋白质的协同沉淀作用。在常温、5MPa加压CO2酸沉8%(质量分数)的湘莲蛋白质乙醇液(体积分数20%乙醇)0.5h时,莲子蛋白沉淀率可达81.2%。结果表明,用文中方法提取湘莲蛋白,湘莲蛋白收率为72.2%,纯度达93%.  相似文献   

7.
超临界CO2萃取鱼腥草的挥发油成分   总被引:12,自引:2,他引:10  
从萃取的压力、温度、流量和时间等条件探讨超临界CO2萃取对鱼腥草(Houttuynia cordata Thunb.)挥发油萃取率的影响,确定最佳萃取条件为萃取压力20mPa、温度35℃、CO2流量40kg/h和萃取时间80min,鱼腥草挥发油得率为1.76%。而水蒸气蒸馏提取和石油醚提取的得率分别为0.05%和0.08%。超临界CO2法萃取的鱼腥草挥发油收率高,萃取时间短。  相似文献   

8.
以海稻米为研究对象,研究提取温度、提取溶剂、料液比、提取时间、提取次数等5个因素对海稻米中γ 氨基丁酸(GABA)提取率的影响,采用正交试验分析方法确定海稻米中GABA最优工艺条件。结果表明:海稻米中GABA的最佳提取工艺为:提取溶剂为水、提取时间为1 h、提取次数3次、提取温度60 ℃、提取物料比1 g∶15 mL,在此提取条件下的提取率为6.2μg/g。  相似文献   

9.
采用紫外照射法对原始菌株进行诱变和筛选,得到一株降解饼粕中粗蛋白能力较强的变异菌株UV—A,能使饼粕中粗蛋白的含量降到15.46%,是原始菌株的1.4倍。把该变异菌株接入到装有12.5kg菜籽饼粕的40L塑料箱内进行固体发酵,发现饼粕中粗蛋白的含量降解到8.9%。并通过正交设计试验确定变异菌株UV—A的培养条件为:NaCl5%,温度30℃,pH7.0,培养时间48h,其中温度对其影响最大。  相似文献   

10.
采用响应面法研究温度、乙醇浓度、质量空速对锌、锰、钴改性的HZSM-5催化乙醇脱水制备乙烯过程中乙烯收率的影响。结果表明反应温度对乙烯收率影响最大,并且各因素之间存在交互作用。用响应面方法确定乙醇脱水制备乙烯的最佳工艺条件是:温度261.3 ℃,乙醇浓度34.4%,质量空速1.18 h?1,在该条件下乙烯收率达到98.69%。  相似文献   

11.
本文研究了以猪毛为原料,经过水解、赶酸、中和、结晶、精制提取出胱氨酸纯品;并从分离胱氨酸后的母液中,经过脱色、离子交换、浓缩、结晶、精制,制备出复合氨基酸.在本工艺条件下,胱氨酸产品的收率为4.8%,纯度在99%以上;复合氨基酸产品的收率为41%,纯度在83%以上.本文为扩大试验打下了基础.  相似文献   

12.
This work demonstrates a significant advance in bioprocessing for a high‐melting lipid polymer. A novel and environmental friendly solvent mixture, acetone/ethanol/propylene carbonate (A/E/P, 1:1:1 v/v/v) was identified for extracting poly‐hydroxybutyrate (PHB), a high‐value biopolymer, from Cupriavidus necator. A set of solubility curves of PHB in various solvents was established. PHB recovery of 85% and purity of 92% were obtained from defatted dry biomass (DDB) using A/E/P. This solvent mixture is compatible with water, and from non‐defatted wet biomass, PHB recovery of 83% and purity of 90% were achieved. Water and hexane were evaluated as anti‐solvents to assist PHB precipitation, and hexane improved recovery of PHB from biomass to 92% and the purity to 93%. A scale‐up extraction and separation reactor was designed, built and successfully tested. Properties of PHB recovered were not significantly affected by the extraction solvent and conditions, as shown by average molecular weight (1.4 × 106) and melting point (175.2°C) not being different from PHB extracted using chloroform. Therefore, this biorenewable solvent system was effective and versatile for extracting PHB biopolymers. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:678–685, 2016  相似文献   

13.
酸解法制取甘草次酸及其纯化工艺   总被引:1,自引:0,他引:1  
以甘草酸单铵盐为原料,酸解制取甘草次酸并利用低温冷析法对其进行精制纯化.通过L9(34)正交试验,确定了酸解甘草次酸的最佳条件:H2SO4体积分数8%、料液比(g/mL)1:100、温度100℃、12 h,在此条件下,转化率可达80.24%:通过对比实验,获得了低温冷析法精制甘草次酸的纯化工艺:酸解产物经水洗、氯仿溶提后,在体积分数30%乙醇溶液中80℃热溶15 min,再在冰水中冷析10 min,最终得到甘草次酸的质量分数为95.79%,得率40.87%.  相似文献   

14.
The optical resolution of (R,S)‐propranolol by the diastereomeric crystallization method was successfully performed using dehydroabietic acid (DHAA) as the resolving agent in methanol. The three important parameters: DHAA amount, solvent (methanol) amount, and crystallization temperature of diastereomeric salts were optimized employing the response surface methodology (RSM). When maintaining a lower limit of 95% for the purity of (S)‐propranolol, the optimal resolution conditions were a DHAA/(R,S)‐propranolol molar ratio of 1.1, solvent/(R,S)‐propranolol ratio of 16.2 mL.g‐1, and crystallization temperature of –5 °C. The desired (S)‐propranolol was prepared with 94.8% optical purity and 72.2% yield under the optimal conditions. Chirality 27:131–136, 2015. © 2014 Wiley Periodicals, Inc.  相似文献   

15.
以啤酒花超临界CO2萃取物剩余残渣为原料,利用响应面法对热回流提取黄腐酚的工艺条件进行了优化。以单因素实验为基础,根据中心组合设计原理,采用响应面分析法,对提取时间、提取温度、提取溶剂、料液比各因子间显著性和交互作用进行分析,得到黄腐酚提取的最佳工艺条件为:乙醇体积分数96%,提取温度为60℃,提取时间为88min,提取料液比为1g∶26mL,在该条件下,黄腐酚得率可达4.05%,纯度为12.31%。  相似文献   

16.
1,3-Oleoyl-2-palmitoylglycerol (OPO), an important structured triglyceride in infant nutrition, was synthesized by a two-step process in high yields and purity using sn1,3-regiospecific lipases. In the first step, tripalmitin (TP) was subjected to an alcoholysis reaction in an organic solvent catalyzed by sn1,3-regiospecific lipases yielding the corresponding 2-monopalmitin (2-MP). The 2-MP was isolated in up to 85% yield and >95% purity by crystallization and esterified in the second step with oleic acid using the same lipases to form the structured triglyceride OPO in up to 78% yield containing 96% palmitic acid in the sn2-position. Water activity, solvent, as well as carrier for lipase immobilization strongly influenced the yield and purity of products in both steps. The best results were achieved with lipases from Rhizomucor miehei and Rhizopus delemar immobilized on EP 100 and equilibrated to a water activity of 0.43. Special emphasis was given to develop this process in solvents that are allowed to be used in foodstuffs and to perform the second step in a solvent-free system.  相似文献   

17.
Through the use of pilot plant equipment, transaldolase types I, II, and III (from Candida utilis) have been separated and purified. The procedure includes a time sensitive solvent fractionation below 0°C, ion exchange chromatography, and crystalization. The enzyme yield represents a 41% recovery of crystalline type III and partially purified types I and II.  相似文献   

18.
在278.2~308.2 K温度范围内,测定阿奇霉素在水/乙醇混合溶剂中的溶解度,根据固液平衡理论建立了该体系的溶解度修正模型。采用X线粉末衍射法和差示扫描量热法,对阿奇霉素在不同温度、不同体积比的水/乙醇混合溶剂中得到的晶体进行鉴别。同时利用溶解度数据估算了阿奇霉素在水/乙醇体系中的溶解热(-25.26~-16.11 k J/mol)、混合热(-9.94~-3.25 k J/mol)。通过溶液化学理论推导了阿奇霉素溶剂化平衡常数K与活度系数γ2的方程:γ2=1/(1+K),建立了溶剂化焓与温度、水/乙醇两者体积比(φ)之间的关系式,为ΔH=RTln(17.86exp(3.4φ)-1)。采用溶析结晶方法得到的6种阿奇霉素晶体,均属单斜晶系,但具有不同的晶胞参数且其密度和熔点也不同。同时发现温度越高,水/乙醇体积比越大,得到的晶体稳定性越差(晶体的熔点和密度降低)。在水/乙醇混合溶剂的溶析结晶体系中,产生阿齐霉素多晶型的现象与溶剂化作用的强弱有关。  相似文献   

19.
微生物发酵产辅酶Q10的高速逆流色谱法分离纯化   总被引:1,自引:0,他引:1  
本文首次将高速逆流色谱法应用于微生物发酵液提取物中辅酶Q10的分离纯化,建立了一套可用于其制备分离的逆流色谱溶剂体系正庚烷-乙睛-二氯甲烷(12:7:3.5, v/v/v)。500mg发酵液粗提物经一步制备分离,可得到绝对纯度在98%以上辅酶Q10130mg。比较表明,该方法较传统的硅胶柱层析和结晶相结合的纯化方法在产物纯度、回收率及产率等方面都有一定的优势。  相似文献   

20.
Lipase catalyzed esterification of glycidol in organic solvents   总被引:1,自引:0,他引:1  
We studied the resolution of racemic glycidol through esterification with butyric acid catalyzed by porcine pancreatic lipase in organic media. A screening of seven solvents (log P values between 0.49 and 3.0, P being the n-octanol-water partition coefficient of the solvent) showed that neither log P nor the logarithm of the molar solubility of water in the solvent provides good correlations between enantioselectivity and the properties of the organic media. Chloroform was one of the best solvents as regards the enantiomeric purity (e. p.) of the ester produced. In this solvent, the optimum temperature for the reaction was determined to be 35 degrees C. The enzyme exhibited maximum activity at a water content of 13 +/- 2% (w/w). The enantiomeric purity obtained was 83 +/- 2% of (S)-glycidyl butyrate and did not depend on the alcohol concentration or the enzyme water content for values of these parameters up to 200 mM and 25% (w/w), respectively. The reaction was found to follow a BiBi mechanism. (c) 1993 John Wiley & Sons, Inc.  相似文献   

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