共查询到20条相似文献,搜索用时 421 毫秒
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为了从头孢氨苄结晶废母液中回收产品,采用大孔树脂吸附法对回收工艺进行了研究,比较了HZ818,HZ832,HZ801,HZ816,D4020,X-5等6种大孔吸附树脂对头孢氨苄的吸附性能,筛选出了高吸附性能的树脂,同时对头孢氨苄在HZ816吸附柱上的动态吸附-解吸过程进行了研究.其结果是:大孔吸附树脂HZ816能更好地分离回收头孢氨苄,其吸附量在45.4mg/mL左右,40%的乙醇(pH 2.0)可以将吸附在树脂柱上的头孢氨苄有效解吸,解吸率达94.5%,解吸液经结晶、干燥等后续处理可得到符合中国药典要求的产品.大孔吸附树脂HZ816是回收头孢氨苄的一种理想的吸附剂,该工艺简捷,具有很好的工业化前景. 相似文献
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用大孔吸附树脂分离利血平 总被引:1,自引:0,他引:1
以利血平的吸附量和解吸率为指标,筛选大孔吸附树脂.研究吸附和解吸的优化条件,并考察选定树脂的吸附等温线、吸附动力学、吸附和解吸性能.结果表明,将催吐萝芙木根粉浸提液蒸去乙醇且不调pH(pH 1)进行吸附,HZ-818型大孔吸附树脂对利血平的吸附量可达到9.34mg/mL.使用工业乙醇-水(80:20,pH 1.0)为解吸剂,解吸率可达99.3%.该树脂的吸附符合Langmuir吸附等温方程.吸附前期,吸附速度较快,以后速度减慢.HZ-818型树脂对利血平的吸附量大,解吸率高,通过大孔树脂吸附和解吸,利血平浓度提高50倍以上,适宜于工业化生产. 相似文献
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大孔吸附树脂提取喜树碱的研究 总被引:29,自引:0,他引:29
本文研究了大孔吸附树脂提取喜树碱的方法,包括树脂的筛选,喜树碱溶液的浓度、温度、PH值和盐离子浓度对吸附的影响,解吸剂的选择,解吸剂的PH值、流速对解吸的影响。确定了适宜的吸附和解吸条件。 相似文献
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Ultrasound-Assisted Extraction of Soyasaponins from Hypocotyls, and Analysis by LC-ESI-MS 总被引:1,自引:0,他引:1
A rapid high-performance liquid chromatographic method with electrospray mass spectrometric detection has been developed for determination of soyasaponins in hypocotyls. Ultrasound-assisted extraction (UAE) was used to prepare the sample, because it was simpler and more effective than conventional extraction methods for extraction of soyasaponins from soybean hypocotyls using methanol, ethanol, or acetonitrile as solvents. Maximum yields of total or individual soyasaponins extracted by UAE were highly dependent on the extraction solvent and on the operating conditions. The maximum amount of total soyasaponins was extracted by use of 40% ethanol in water. The effects of extraction temperature and time were also investigated, and the stability of soyasaponins during UAE was examined. Soyasaponins could be extracted without decomposition from soybean hypocotyls by three-fold UAE with 40% ethanol at 25 °C for 20 min. The calibration plot was linear (r 2 > 0.991) in the concentration range 0.01–1.0 mg L?1 for each soyasaponin, with a lower limit of quantification less than 4.0 ng m L?1. Intra-day and inter-day relative standard deviations (RSD) were less than 9.2 and 13.1%, respectively. The method was applied to routine analysis of soyasaponins in hypocotyls. 相似文献
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Rapid quantification and characterization of soyasaponins by high-performance liquid chromatography coupled with electrospray mass spectrometry 总被引:1,自引:0,他引:1
A method using high-performance liquid chromatography (HPLC) with electrospray ionization mass spectrometry (ESI-MS) in the negative mode is presented for the quantification and characterization of different soyasaponins using six authentic soyasaponin standards. This method was successfully applied to the rapid separation of diverse soyasaponins, more than 50, including soyasaponins A in different degrees of acetylation, and soyasaponins B in both their 2,3-dihydro-2,5-dihydroxy-6-methyl-4H-pyran-4-one (DDMP)-conjugated and non-conjugated forms in different samples in one single run for only 30 min. Standard calibration curve was linear over the concentration range of 0.010-1.0 mg/L for each soyasaponin. Within-day and day-to-day relative standard deviations were less than 9.2 and 13.1%, respectively. 相似文献
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Decroos K Vincken JP Heng L Bakker R Gruppen H Verstraete W 《Journal of chromatography. A》2005,1072(2):185-193
A novel method utilizing high-performance liquid chromatography (HPLC) with evaporative light scattering detection (ELSD) and electrospray ionisation mass spectrometry (ESI-MS) was developed for the analysis of soyasaponins, a divers group of triterpenic compounds with one or two sugar side chains, occurring in soy. Group A soyasaponins in different degrees of acetylation, as well as group B soyasaponins in both their 2,3-dihydro-2,5-dihydroxy-6-methyl-4H-pyran-4-one (DDMP)-conjugated and non-conjugated forms could be separated and quantified using authentic soyasaponin standards, in one single run. The method was tested by the determination of the soyasaponin content and composition of eight soygerm samples of different origin. Differences in the composition and the degree of acetylation of the group A soyasaponins were observed among these samples. The group B soyasaponins showed much less variability and they were mainly present in their DDMP-conjugated form. 相似文献
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Lijie Zhu Minghan Zhang Xiuying Liu He Liu Yutang He Bo Wang Tao Ma 《Chemical Papers》2017,71(3):653-660
Soyasaponins were shown to have a wide range of biological activities in previous studies; however, the activities of their monomeric compounds are unclear. The aim of this study was to evaluate the in vitro antioxidant activities of soyasaponins in HepG2 cells. Four soyasaponins were isolated from soy hypocotyls and identified as soyasaponin Aa, Ab, Ba, and Bb. The protective effects of these soyasaponins against production of hydrogen peroxide-induced reactive oxygen species in cells were investigated. The cellular antioxidant activity of soyasaponins was found to be in a dose-dependent manner at concentrations ranging between 25 and 400 μg/mL in 24 h. Finally, based on cell morphology observations, group A soyasaponins showed better cellular antioxidant activity and anti-oxidative enzyme activity than group B ones, with an optimal concentration of 100 μg/mL. 相似文献
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Efficient protocol for isolation and purification of different soyasaponins from soy hypocotyls 总被引:1,自引:0,他引:1
Soyasaponins are naturally occurring triterpenoid glycosides associated with many biological activities. The aim of the present study was to develop an effective method for isolation and purification of differently glycosylated, acetylated, and 2,3‐dihydro‐2,5‐dihydroxy‐6‐methyl‐4H‐pyran‐4‐one (DDMP)‐conjugated soyasaponins from soy hypocotyls. Both gel filtration using Sephadex LH‐20 chromatography (Amersham Pharmacia Biotech AB; elution phase: methanol, flow rate: 3.0 mL/min, sample loading: 60 mg) and high‐speed countercurrent chromatography (stationary phase: n‐butanol–acetic acid (5.0%, v/v), mobile phase: water flow rate: 3.0 mL/min, sample loading: 100 mg) could effectively fractionate isoflavones and soyasaponins from the crude extract with yield of soyasaponin complexes 20.5 mg and 22.3 mg, respectively. After fractionation, the soyasaponin complexes could be purified further using preparative HPLC to separate individuals. A total of nine soyasaponins, triacetyl soyasaponin Ab (yield 1.55%, HPLC purity >98%), Aa (2.68%, >99%), Ab (18.53%, >98%), Ae (0.85%, >98%), Ba (0.63%, >91%), Af (1.12%, >85%), Bb (3.45%, >98%) and Be (0.59%, >76.8%) were obtained. DDMP‐conjugated groups, αg (2.06%, >85%), βg (7.59%, >85%), and γg (0.29%, >85%) that were very labile even in mild conditions, were also collected. The method described here can be used as an effective protocol to separate different soyasaponins occurring in the original sample. 相似文献
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G. Pfrepper 《Journal of chromatography. A》1976,120(2):399-409
Ion exchange at high concentrations of the mobile phase. VI. The influence of the degree of crosslinking on the sorption of anionic complexes of Tl(III) and Fe(III) by sulphonic cation exchangers The sorption of TI(III) and Fe(III) on sulphonic cation exchangers with 2-16% divinylbenzene has been investigated. In the range of concentration 4-8 mol/1 HBr and 4-10 mol/l HC1 the distribution coefficients decrease with the degree of crosslinking of the matrix. The same dependence has been observed for the selectivity of sorption, i.e. the quotient of the volume distribution coefficient of the trace component and the Donnan coefficient of the electrolyte. 相似文献
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The sorption of 1,8-dihydroxy-2-(pyrazol-5-ylazo)-naphthalene-3,6-disulfonic acid onto the anion exchange resins Dowex 1-X8 and Dowex 2-X8 from aqueous solutions of between pH 1 and 10 was studied spectrophotometrically. Conditions for obtaining modified sorbents with a given capacity for the azo compound were investigated. The absorption and reflectance spectra of the sorbed dye were traced. The immobilized reagent retained chromic characteristics similar to those it had in solution. The mechanism of sorption was investigated under static conditions in the temperature range of 0 to 25°C by following the amount of sorbed dye as a function of contact time. The sorption was a first-order process in all cases. Pore diffusion was found to be the rate-limiting step in the sorption process. Diffusion coefficient values of from 6.0 × 10–7 to 7.4 × 10–7 cm2/s were calculated from the experimental results. The values of the activation energy of PACA sorption were found to be –8.56 and –8.05 kJ/mol for Dowex 1-X8 and Dowex 2-X8, respectively. 相似文献
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The water sorption of several starch samples and resistant starch (RS) samples were analyzed using an equilibrium solution-gel structure model and the results were compared to various sorption theories. It is found that the water sorption relations to water activity in starch in the high water content region could be properly described by the equilibrium two-phase structural model. The results suggested that favorable starch-starch interaction determined the formation of starch gel in water. The gel structure had a high molecular modulus of 108 Pa and thus had limited water sorption capability. Part of the starch also exhibited the solution properties with water due to chain ends and defects of the gel structure. Despite the unfavorable starch-water interaction, starch-water solution might be formed due to the predominant contributions from the entropy of mixing. The solution phase was responsible for the rapid increase of water sorption at high water activity. It was also demonstrated that the starch could maintain a maximum dynamic unfreezable water up to ≈ 36%, which was consistent with the DSC measurements. © 1996 John Wiley & Sons, Inc. 相似文献
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El-Safty SA 《Journal of colloid and interface science》2003,260(1):184-194
The sorption of phenol, and o-, m-, and p-aminophenol (o-, m-, and p-AP) onto highly ordered mesoporous silicas (HOM) with cubic Im3m (HOM-1), hexagonal H(I) (HOM-2), 3-D hexagonal p6(3)/mmc (HOM-3), cubic Ia3d (HOM-5), lamellar L( infinity ) (HOM-6), and solid phase S (HOM-8) materials has been investigated kinetically. Nanostructured silica molecular sieves have been prepared at 25 and 60 degrees C with lyotropic liquid-crystalline phases of the nonionic surfactant (Brij 76) that was used as a structure-directing agent. Such nanostructured silicas have been studied by 29Si nuclear magnetic resonance (29Si NMR), powder X-ray diffraction (XRD), the Brunauer-Emmett-Teller (BET) method for nitrogen adsorption and surface area measurements, and transmission electron microscopy (TEM) techniques after synthesis and sorption. It was found that all materials exhibit well-defined long-range porous architectures without significant loss of the ordered texture during phenol sorption. The kinetics of phenol sorption has been studied spectrophotometrically at different temperatures (25-40 degrees C; +/-0.1 range). The sorption rate is zero order in all phenols sorbed, and increases directly in the pattern P >m-AP > o-AP > p-AP, which reflects the mobility of the phenol compounds on the particle pores. The isothermal sorption and the kinetic parameters were discussed and it was established that a diffusion-controlled process characterizes phenol sorption. Furthermore, the mechanism of phenol sorption was deduced to be predominantly particle diffusion. The diffusion coefficients were determined using Fick's equation. The trend of diffusion of all phenols onto nanoporous silica was HOM-8 > HOM-2 > HOM-6 > HOM-5 > HOM-1 > HOM-3, reflecting the effect of the uniform pore size distribution and the internal surface area of the nanostructured silicas on the diffusion process. 相似文献
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Sorption of europium on zirconium oxide has been studies as a function of shaking time, concentration and nature of electrolyte. The effect of initial europium concentration and the amount of adsorbent has been investigated in the range from 6.6·10–10 to 6.6·10–8 mol·dm–3 and between 10 to 200 mg of the oxide. Maximum sorption (>99.8%) from pH 10 buffer and low sorption (<3%) was observed from 0.01 mol·dm–3 nitric or perchloric acid solution. Citrate, sulfate, EDTA and carbonate reduced the sorption significantly. Under optimal conditions Ag(I), Cs(I), Tc(VII), Sb(V), Cu(II), Nd(III), Fe(III), and especially Nd and Fe showed low distribution coefficients. The data followed both Dubinin-Radushkevich and Langmuir-type isotherms. The mean free energy, of sorption was evaluated to be 10.1 kJ mol–1 and the sorption capacity was found to be 22.2 mmol g–1, using the Dubinin-Radushkevich isotherm. 相似文献