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1.
为了改进辣根过氧化物酶的提纯方法,在双水相萃取的基础上使用聚乙二醇(PEG6000)在高饱和度(NH4)2SO4中沉淀辣根提取液中的过氧化物酶,利用磷酸盐溶液复溶解共沉淀物形成的双水相萃取体系能高效回收高纯度酶蛋白。研究了pH、PEG浓度和(NH4)2SO4饱和度对酶活性的影响,并考察不同液固比、pH和NaCl浓度对目标酶在双水相体系中的分配行为,并通过响应面法优化出最优萃取条件。结果表明:在液固比0.3 m L/g、pH7.02和NaCl 42 g/L的优化萃取条件下,辣根过氧化物酶回收率达88.1%,酶纯度较优化前提高了21.7倍。该方法的建立对于微量蛋白质的高效率提纯具有重量的参考价值。  相似文献   

2.
采用乙醇-磷酸氢二钾(K2HPO4)双水相体系萃取L-精氨酸。实验考察了乙醇浓度、K2HPO4浓度、pH、萃取温度对萃取分离L-精氨酸的影响。结果表明,L-精氨酸在该双水相体系的分配系数K随体系乙醇浓度、K2HPO4浓度的增大、萃取温度的升高而增大,随着体系pH的增大而减小;L-精氨酸在该双水相体系的萃取率随体系乙醇浓度和pH的增大而减小,随着体系K2HPO4浓度增大、萃取温度的升高而增大。  相似文献   

3.
离子液体双水相体系及其在生物分离中的应用   总被引:5,自引:0,他引:5  
作为一种高效而温和的新型绿色分离体系,离子液体双水相体系结合了离子液体和双水相体系的优点。因此倍受国内外研究者的青睐。介绍了双水相萃取技术的原理和离子液体双水相体系;综述了离子液体双水相体系在生物分离中的研究进展,主要包括抗生素、蛋白质、和食用色素等的萃取分离;并展望了离子液体双水相体系在生物分离中的应用前景。  相似文献   

4.
用聚乙二醇(PEG)/羟丙基淀粉(ReppalPES)双水相体系两步法从黄豆中分离磷酸甘油酸激酶(PGK)和磷酸甘油醛脱氢酶(GAPDH)。PGK在上相收率及GAPDH在下相收率均在80%以上。放大采用离心倾析机(decanter)连续处理匀浆液,用离心萃取器(separator)完成双水相体系的萃取两相分离。整个工艺具有处理量大、接触时间短、酶收率高的优点  相似文献   

5.
微生物胞内产物分离的新方法—双水相萃取技术   总被引:1,自引:0,他引:1  
本文简要地介绍了双水相萃取技术的概念,综述了双水相取技术的特点及其在内产物分离中的应用,讨论了影响细胞碎片的去除和双水相萃取效果的参数,以及成相材料的回收利用等问题,展示了双水相萃取技术的新发展。  相似文献   

6.
双水相萃取分离技术的评价和展望   总被引:9,自引:0,他引:9  
谭天伟  沈忠耀   《微生物学通报》1996,23(6):368-370,363
双水相萃取分离技术的评价和展望谭天伟(北京化工大学化工系,北京100029)沈忠耀(清华大学化工系,北京100084)自1956年瑞典伦德大学的Albertsson发现双水相体系[1]到1979年德国GBF的Kula等人将双水相萃取分离技术应用于生物...  相似文献   

7.
建立了由亲水性离子液体1-辛基-3-甲基咪唑二氰铵盐([C8mim][N(CN)2])和(NH4)2SO4形成的双水相萃取体系并应用于银杏黄酮的分离纯化研究。研究了盐浓度、体系温度、pH值、NaCl量等因素对银杏黄酮萃取效率的影响;并对下相中无机盐进行回收。体系由18.52%[C8mim][N(CN)2],25.93%(NH4)2SO4构成,加入1.5 mmol NaCl,在室温下进行萃取时萃取效率最佳,在最佳的条件下[C8mim][N(CN)2]/(NH4)2SO4体系对银杏黄酮的萃取效率达96.73%。与传统的双水相体系相比,该体系的萃取效率高,粘度低,同时(NH4)2SO4的回收率达90.54%。[C8mim][N(CN)2]/(NH4)2SO4双水相体系是一种很好的分离纯化银杏黄酮的方法。  相似文献   

8.
建立稳定的聚乙二醇(PEG)与(NH4)2SO4双水相体系以分离人参根中人参皂苷。通过上下相体积比(R)、分配系数(K)和回收率(Y)分析双水相体系对人参皂苷的萃取效果,研究了PEG分子量、PEG/(NH4)2SO4质量分数、pH值和温度等因素对双水相成相及人参皂苷萃取的影响。结果表明:PEG分子量为3350、PEG3350的质量分数为12%、(NH4)2SO4质量分数为16%、溶液pH为7.0、温度为60℃时,双水相体系对人参皂苷有较高的萃取率,回收率可到达88.94%。  相似文献   

9.
为得到红梅消中总皂苷的最佳提取工艺参数,首次采用硫酸铵-乙醇双水相体系对其进行提取;以双水相中两相的质量百分比为自变量,以红梅消总皂苷得率为因变量,通过确定中心点及缩小变量取值范围,用星点设计-效应面分析法进行优化,得到双水相最佳提取条件:硫酸铵12.14%,乙醇40.00%,总皂苷得率为2.95%。结果表明用星点设计-效应面分析法筛选双水相各相的质量百分比方法可行性高,结果可靠;双水相体系对红梅消总皂苷有较好的提取作用,工艺简单、节能、易放大于工业生产。  相似文献   

10.
双水相体系萃取分离杜仲叶中桃叶珊瑚甙的研究   总被引:5,自引:2,他引:3  
建立了由高分子化合物聚乙二醇(PEG4000)与葡聚糖40000(D40)形成的双水相体系萃取分离杜仲叶中桃叶珊瑚甙的新方法.考察了萃取体系相图,研究了PEG4000/D40质量分数、样品溶液加入量、pH值和温度等因素对双水相成相及桃叶珊瑚甙萃取率的影响.结果表明:PEG4000的质量分数为11%,D40质量分数为8%、样品溶液加入量为8 g,温度为60℃,溶液pH为7时,双水相体系对桃叶珊瑚甙有较高的萃取率,重复三次可达到66.32%,而且萃取得到的桃叶珊瑚甙产品的纯度达到48.67%,远远高于粗提物中的8.750%.  相似文献   

11.
Wang H  Dong Y  Xiu ZL 《Biotechnology letters》2008,30(12):2079-2084
Microwave-assisted, aqueous two-phase extraction was investigated to obtain effective constituents, including piceid, resveratrol and emodin in Polygonum cuspidatum. An aqueous two-phase system consisting of 25% (w/w) ethanol 21% (w/w) (NH4)2SO4 gave equal yields of piceid, and 1.1- and 1.9-times higher yields of resveratrol and emodin, respectively, than that achieved by microwave-assisted extraction and heat reflux extraction. Three-separate operations, extraction, clarification and concentration, are hereby integrated into a single step to get higher yields at lower cost. This is therefore a potentially useful method for the extraction and purification of target products.  相似文献   

12.
采用无水乙醇C2H5OH/硫酸铵(NH4)2SO4双水相体系分离白头翁中的黄酮。确定双水相体系组成为21%C2H5OH/22%(NH4)2SO4,通过单因素试验和Box-Benhnken实验设计探讨黄酮粗提液质量分数、NaCl质量分数和pH值对萃取效果的影响。确定最佳萃取条件为:黄酮粗提液质量分数12.5%,NaCl质量分数1.5%,pH 5.99,在此条件下,白头翁总黄酮主要分布在上相,萃取率可达73.6%。  相似文献   

13.
以竹叶黄酮水提溶液为原料,采用PEG(聚乙二醇)/(NH4)2SO4双水相体系对竹叶黄酮进行萃取,考察了PEG平均相对分子质量、PEG质量分数、(NH4)2SO4质量分数、pH值、NaCl质量分数、原液质量分数、萃取温度等对双水相及竹叶黄酮萃取效果的影响。双水相萃取法提取竹叶黄酮的最优条件为:PEG 400 31%,(NH4)2SO411%,pH 3.9,NaCl 0.7%,原液51.5%,萃取温度20℃,在此条件下得到的竹叶黄酮萃取率为97.8%。结果说明,双水相萃取法操作简单方便,成本低,不会引起生物质失活或变性,适合于黄酮类化合物的萃取分离。  相似文献   

14.
本研究利用黑曲霉发酵花生根产生的纤维素酶来酶解花生根中的纤维,破坏其细胞壁,有利于自藜芦醇的提取。同时对发酵后的花生根白藜芦醇的提取进行优化。根据中心组合实验设计原理,采用四因素五水平的响应面分析法优化发酵后花生根中自藜芦醇的提取,响应面分析表明乙醇浓度、提取温度、提取时间和液固比对花生根白藜芦醇提取率有显著影响,且不是简单的线性关系。得到最佳的提取条件为乙醇浓度64%,提取温度55℃,提取时间60min,液固比8:1,在此条件下,自藜芦醇得率为0.191%。  相似文献   

15.
The metabolites of arachidonic acid known as the leukotrienes are a class of lipid mediators which have potent and diverse biological effects in pulmonary tissue. Leukotrienes C, D, and E (LTC4, LTD4, and LTE4) are known to be principal mediators of immunoglobulin E (IgE)-mediated hypersensitivity reactions in lung tissue. It is therefore important to develop reliable and quantitative isolation techniques for estimating levels of these mediators in tissue. In this study, LTC4, LTD4, and LTE4 were separated from other arachidonate metabolites by organic extraction procedures. 5-Hydroxyeicosatetraeonic acid and leukotriene B4 extract efficiently into the organic layer of aqueous:ether or aqueous:chloroform extractions, whereas arachidonate metabolites containing conjugated peptides (e.g., LTC4, LTD4, and LTE4) failed to extract into these organic solvents. An extraction step was therefore developed that affords quantitative extraction of LTC4, LTD4, and LTE4 into the organic phase of an isopropanol:ether:H2O mixture. This step is the key for a two-step extraction method that isolates histamine, LTC4, LTD4, and LTE4 with a recovery of 100, 85, 75, and 57%, respectively. One advantage of this separation procedure for obtaining these mediators by organic extraction is an ability to expediently process many samples. Furthermore, the leukotriene content of extracted samples can be analyzed using the guinea pig ileum bioassay without interference from vasoamines or platelet-activating factor. These later substances are eliminated from leukotriene-enriched fractions by this extraction process. When histamine and LTC4 were added to supernatant fluids recovered from isolated lung tissue, they were quantitatively recovered using this extraction method.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

16.
We have recently demonstrated the cardioprotective effects of a non-alcoholic extract of Argentinian red wine (RWE) on ischemia-reperfusion injury. The aim of the present study was to assess the relative contribution of four phenolic fractions separated from RWE by liquid/liquid extraction with solvents of decreasing hydrophobicity, to the myocardial protection achieved by the original extract. Isovolumic perfused rat hearts treated with each fraction 10 min before ischemia and the first 10 min of reperfusion were submitted to a 20-min global ischemic period followed by 30 min of reperfusion. The treatment with the fraction rich in polymeric proanthocyanidins (fraction IV = aqueous residue) significantly improved the postischemic recovery of left ventricular developed pressure (LVDP) and +dP/dt (max) (111 +/- 5% and 117 +/- 6% vs 61 +/- 4%, 62 +/- 5% , respectively, detected in control hearts) and abolished the increase of left ventricular end diastolic pressure (LVEDP) (8 +/- 2 mmHg vs 42 +/- 4 mmHg in untreated hearts). However, the fraction rich in anthocyanins (III: butanol) elicited a cardioprotective action weaker than the original extract. On the other hand, the representative of either resveratrol or flavan-3-ols and flavonols (fractions I and II) failed to induce this type of response. LDH release and TBARS concentration were significantly lowered after treatment with fraction IV alone. These data show that the fraction rich in polymeric proanthocyanidins exerts a protective effect against myocardial alterations derived from ischemia and reperfusion comparable to the original RWE. This beneficial effect can be correlated to the ability of that fraction to attenuate the degree of lipid peroxidation.  相似文献   

17.
To identify the major metabolites of resveratrol in rat, rat urine samples were pretreated by using solid-phase extraction technique (SPE) with polyamide cartridges. And a LC-MS/MS method with electrospray ionisation (ESI), negative ion mode and collision induced dissociation (CID), was used to elucidate the structures of the major metabolites of resveratrol. According to the results of our experiment, we found that the main metabolites of resveratrol were resveratrol monoglucuronide (M1), dihydroresveratrol monosulfate (M2), resveratrol monosulfate (M3) and dihydroresveratrol (M4).  相似文献   

18.
石慧  陈媛梅 《生物磁学》2008,(5):854-857
目的:寻找加杨叶粗提液中的总黄酮的有效方法。方法:利用双水相体系萃取分离、紫外分光光度法直接测定。结果:萃取分离加杨叶总黄酮的最佳双水相体系是25%PEG400与12%(NH4)2SO4,最佳萃取条件为:pH=9,NaCl的添加量为3%,粗提液3mL,温度25℃。结论:该方法的相对标准偏差(RSD)≤0.28%(n=5),具有良好的精密度和选择性,为黄酮类化合物萃取分离的一种有效方法。  相似文献   

19.
大孔吸附树脂分离虎杖中白藜芦醇的研究   总被引:7,自引:0,他引:7  
目的:采用大孔吸附树脂对虎杖粗提物中白藜芦醇进行初步富集、分离和纯化.方法:考察18种树脂对白藜芦醇的吸附量和解吸率,选择吸附量大、解吸率高的数种树脂进行吸附动力学研究,确定最佳的脱附工艺.结论:HPD-500树脂对白藜芦醇的吸附量可达58.67mg/g,解吸率为92.6%,经大孔吸附树脂的吸附与解吸,白藜芦醇的含量由粗提物中9.25%提高至39.5%.  相似文献   

20.
《Harmful algae》2002,1(2):127-135
Domoic acid (DA) is a marine neurotoxin that is somewhat unstable, particularly in acidic media. Several protocols were used to extract DA from naturally contaminated tissues of shellfish harvested in Portugal. A modified version of AOAC method no. 991.26, with a simplified 10 g extraction, was used and compared with an aqueous 50% methanol extraction. Mean recoveries were between 81 and 85% when extracts were analysed by LC on the same day of extraction. When acid extracts were frozen for 1 or 2 days recoveries lowered to 72%, and if injection was repeated on the following 3rd or 4th days only 57–65% was recovered. Relative standard deviation of recovery for these miscellaneous samples, which was between 10 and 13% on the day of extraction, increased approximately 10% each day the extract was reanalysed. On our regulatory monitoring work, we employ an aqueous 80% methanol extraction that is common with the lipid-soluble DSP toxins. We report here a mean recovery of 90±6% for this methodology. Our long-term stability studies of domoic acid in shellfish extracts showed that slow decomposition of this compound occur in filtered aqueous methanol extracts. Additionally, we also found that in frozen tissues slow decomposition is clearly observable over a time span of 1 month.  相似文献   

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