Academic literature on the topic 'Fructose Separation'

Fructose and glucose are commonly present together in mixtures and may need to be separated. Current separation methods for these isomers are complex and costly. Nanofiltration is a cost-effective method that has been widely used for separating carbohydrates of different sizes; however, it is not commonly used for such similar molecules. Here, we report the separation of fructose and glucose in a nanofiltration system in the presence of fructooligosaccharides (FOS). Experiments were performed using a pilot-scale filtration setup using a spiral wound nanofiltration membrane with molecular weight cutoff of 1 kDa. We observed three important factors that affected the separation: (1) separation of monosaccharides only occurred in the presence of FOS and became more effective when FOS dominated the solution; (2) better separation was achieved when the monosaccharides were mainly fructose; and (3) the presence of salt improved the separation only moderately. The rejection ratio (Rf/Rg) in a fructose/glucose mixture is 0.92. We reported a rejection ratio of 0.69, which was observed in a mixture of 50 g/L FOS with a fructose to glucose ratio of 4.43. The separation is hypothesized to occur due to selective transport in the FOS layer, resulting in a preferential binding towards fructose.

Fructosyl oligosaccharides, including fructo-oligosaccharide (FOS), are gaining popularity as functional oligosaccharides and have been found in various natural products. Our previous study suggested that maple syrup contains an unidentified fructosyl oligosaccharide. Because these saccharides cannot be detected with high sensitivity using derivatization methods, they must be detected directly. As a result, an analytical method based on charged aerosol detection (CAD) that can detect saccharides directly was optimized in order to avoid relying on these structures and physical properties to clarify the profile of fructosyl oligosaccharides in maple syrup. This analytical method is simple and can analyze up to hepta-saccharides in 30 min. This analytical method was also reliable and reproducible with high validation values. It was used to determine the content of saccharides in maple syrup, which revealed that it contained not only fructose, glucose, and sucrose but also FOS such as 1-kestose and nystose. Furthermore, we discovered a fructosyl oligosaccharide called neokestose in maple syrup, which has only been found in a few natural foods. These findings help to shed light on the saccharides profile of maple syrup.

Liquid sugar available today is usually the result of dissolving granulated sugar using hot water. Sorghum syrup can be obtained from the concentrate without involving crystallization, centrifugation, sieving and drying and dissolving processes. However, the sorghum syrup produced from the concentrate still containing complex sugar components such as sucrose, sugar, fructose and others. This review was examined the separation of fructose from sorghum syrup using the HPLC approach. Compared with artificial sweeteners or sugar derivative products such as dextrose, maltodextrin, sorbitol, saccharin, sucralose, and xylitol, sorghum syrup still has lower economic value. The manufacture of these sugar derivatives generally uses chemical processes such as chlorination of sucralose, hydrogenation of xylitol or enzymatic processes and fermentation of fructose. Chemical processes in general can pose a danger to consumer health, while enzymatic and biological processes require high operational costs and complex processes of enzyme and cell separation such corn fructose production. Chromatography is a technology for separating complex mixtures such as sorghum concentrates to obtain separate components, such as fructose syrup and byproducts. On a laboratory scale, sugar fractionation or fructose purification is generally carried out using High Performance Liquid Chromatography (HPLC) with the Carbopac ion exchange column as the stationary phase and ultrapure water as the mobile phase. The industrial scale fractionation in the food sector is still applied to palm oil processing. This is a great opportunity to conduct research related to the components of sorghum concentrates using chromatography column fractionation technology to obtain pure fructose with greater process efficiency and economics.

AbstractA kairomone from white mustard, Sinapis alba , that attracts infective juveniles (J2) of the beet cyst nematode, Heterodera schachtii, was extracted from root exudates and enriched by rotary evaporation. The kairomone-containing root exudate fractions were then repeatedly enriched and separated on a combination of octyl and octadecyl columns, leaving a single UV-absorbing HPLC peak. Glucose and fructose were identified by a subsequent HPLC separation in the ion moderated partition chromatography mode. The kairomone appeared in the fructose-containing fraction. As fructose did not cause nematode attraction, the fructose fraction contained at least one further substance. HPLC separations showed that the kairomone shares several properties with fructose and that it is relatively more polar than those compounds giving an UV signal. The repeated reversed-phase and ion moderated partition chromatography separations of single kairomone-containing fractions indicate that the kairomone is composed of one single substance which could not be identified with the methods applied. Gas chromatographic and mass spectrometric analyses revealed the presence of glucose, fructose, myo-inositol, sucrose and xylofuranose/ribofuranose in S. alba root exudates.

A literature review of work carried out on batch and continuous chromatographic biochemical reactor-separators has been made. The major part of this work has involved the development of a batch chromatographic reactor-separator for the production of dextran and fructose by the enzymatic action of the enzyme dextransucrase on sucrose. In this reactor, simultaneous reaction and separation occurs thus reducing downstream processing and isolation of products as compared to the existing industrial process. The chromatographic reactor consisted of a glass column packed with a stationary phase consisting of cross linked polysytrene resin in the calcium form. The mobile phase consisted of diluted dextransucrase in deionised water. Initial experiments were carried out on a reactor separtor which had an internal diameter of 0.97cm and length of 1.5m. To study the effect of scale up the reactor diameter was doubled to 1.94cm and length increased to 1.75m. The results have shown that the chromatographic reactor uses more enzyme than a conventional batch reactor for a given conversion of sucrose and that an increase in void volume results in higher conversions of sucrose. A comparison of the molecular weight distribution of dextran produced by the chromatographic reactor was made with that from a conventional batch reactor. The results have shown that the chromatographic reactor produces 30% more dextran of molecular weight greater than 150,000 daltons at 20% w/v sucrose concentration than conventional reactors. This is because some of the fructose molecules are prevented as acting as acceptors in the chromatographic reactor due to their removal from the reaction zone. In the conventional reactor this is not possible and therefore a greater proportion of low molecular weight dextran is produced which does not have much clinical use. A theoretical model was developed to describe the behaviour of the reactor separator and this model was simulated using a computer. The simulation predictions showed good agreement with experimental results at high eluent flowrates and low conversions.

The equilibria of adsorption on calcium and hydrogen forms of zeolite Y by equimolar solutions of 12.5 %, 20%, 25%, 30% and 35% w/v of mixtures of glucose, G and fructose, F
also the non-equimolar mixtures of 20% w/v glucose - 30% w/v fructose, 30% w/v glucose - 20% w/v fructose, 25% w/v glucose &ndash
35% w/v fructose, and 35% w/v glucose-25% w/v fructose solutions, which were prepared 24 hours in advance at the experimental temperature, have been studied batch wise at 50º
C. Glucose adsorption, in solutions that had adsorption differences, was fast on both zeolites, on the contrary of slow adsorption of fructose with the stable dynamics. Both adsorptions had small amounts of adsorption changes after minute 30. The treatments made under the same conditions with the same mixtures showed Ca-Y zeolite had better separation capacity compared to H-Y zeolite. Some trials were repeated with CaCl2 added to the solutions. The slowed down affection of fructose adsorption in spite of the small change of glucose adsorption led to better separation. Samples were analyzed by classical methods, not HPLC. All the data were considered with various models and their convergence numbers were tested for their closeness to reality. The models were analyzed by response surface methodology and some of those models had correlation factors as high as 88% at the equilibrium points at 30th minutes. Besides, time dependent models have been considering the lag times with a time dependent variable included all the data of all treated solutions with correlation as high as 79.5%.

Simulated moving bed chromatography process (SMBCP) is the technical realisation of a countercurrent adsorption process through the cyclic port switching. SMB technology reduces the cost of packing material with high loading capacity and provides high purity and high recovery in a very short time. Major commodity applications have been found in the petroleum, food, biotechnology, pharmaceutical and fine chemical industries. The industrial applications bring an emergent demand to improve the SMBCP operation for higher product quality, productivity, efficiency and robustness. However, for this particular process, we encounter several challenges. Firstly, the interplay of the effects of strong nonlinearities, competition of solutes, mass transfer resistance and fluid dynamic dispersion produces steep concentration fronts. Mathematical model accounted for this particular property constitutes a serious difficulty for the solution procedure. Secondly, a dynamic SMB model consists of a set of partial differential, ordinary differential and algebraic equations, which are highly coupled. The large size is a problem due to its intensive computation when on-line optimisation and real-time control are necessary. Thirdly, the SMB unit operation exhibits complex dynamics. Process metrics for design and operation can be determined only when a cyclic steady state is reached after a certain number of switching. Achieving this steady state by solving the PDE models cycle after cycle involves expensive calculation. Studies have been carried out to solve these problems through process analysis, investigation on spatial discretisation techniques, and development of an accelerated integration scheme.Through a systematic study on the advances of SMB modelling, design and control, a set of functionally equivalent models for SMBCP are identified and summarized for their practical applications. The limitations of the existing modelling techniques in industrial applications are also identified. Furthermore, structural analysis of the existing models is conducted for a better understanding of the functionality and suitability of each model. Suggestions are given on how to choose an appropriate model with sufficient accuracy while keeping the computational demand reasonably low for real time control.Effort is made on to the systematic investigation of different numerical methods for the solution of PDEs to circumvent the steep gradients encountered in chromatographic separation. Comprehensive studies are conducted on a single column chromatographic process represented by a transport-dispersive-equilibrium linear model. Numerical solutions from the upwind-1 finite difference, wavelet-collocation, and high resolution methods are evaluated by quantitative comparisons with the analytical solution for a range of Peclet numbers. It reveals that for a PDE system with a low Peclet number, all existing numerical methods work well, but the upwind finite difference method consumes the most time for the same degree of accuracy of the numerical solution. The high resolution method provides an accurate numerical solution for a PDE system with a medium Peclet number. The wavelet collocation method is capable of catching up steep changes in the solution, and thus can be used for solving PDE models with high singularity.The advantages and disadvantages of the wavelet based approaches are further investigated through several case studies on real SMBCP system. A glucose-fructose separation process is firstly chosen with its relatively simple isotherm representations. Simulations are conducted using both wavelet collocation and upwind finite difference methods. For more complicated applications, an enantiomers separation process is selected. As the PDEs model exhibit a certain degree of singularity, wavelet collocation and high resolution methods are adopted for spatial discretisation. It is revealed that both the wavelet based approaches and high resolution methods are good candidates in terms of computation demand and prediction accuracy on the steep front. This is the first time that these two frontier numerical methods are used for such a complex SMB system models and our results are encouraging for the development of model-based online control scheme.In developing a new scheme to rapidly obtain the solution at steady state for any arbitrary initial condition, the concept of Quasi-Envelope (QE) is adopted under the consideration that a SMBCP can be treated as a pseudo-oscillatory process because of a large number of continuous switching. The scheme allows larger steps to be taken to predict the slow change of starting state within each switching. Combined with previously developed wavelet-based technique, this method is successfully applied to the simulation of a SMB sugar separation process. Investigations are also carried out on the location of proper starting point for the algorithm and on the effect of changing stepsize to the convergence of iteration method. It is found that if the starting state of Quasi-Envelope is chosen to be the same as the original function, the multivalue algorithm would require similar computational effort to achieve the steady state prediction, regardless of the integration stepsize. If using constant stepsize, launching QE later is helpful when quasi-envelope displays steep change at the start-up period. A changing stepsize produces slow convergence compared to the constant stepsize strategy, thus increasing the work load where the stepsize change is occurring. Other iteration method is required to be imposed to achieve faster convergence right from the beginning. Potential applications can be seen for other chemical engineering processes with inherent cyclic behaviour.

Simulated moving bed chromatography process (SMBCP) is the technical realisation of a countercurrent adsorption process through the cyclic port switching. SMB technology reduces the cost of packing material with high loading capacity and provides high purity and high recovery in a very short time. Major commodity applications have been found in the petroleum, food, biotechnology, pharmaceutical and fine chemical industries. The industrial applications bring an emergent demand to improve the SMBCP operation for higher product quality, productivity, efficiency and robustness. However, for this particular process, we encounter several challenges. Firstly, the interplay of the effects of strong nonlinearities, competition of solutes, mass transfer resistance and fluid dynamic dispersion produces steep concentration fronts. Mathematical model accounted for this particular property constitutes a serious difficulty for the solution procedure. Secondly, a dynamic SMB model consists of a set of partial differential, ordinary differential and algebraic equations, which are highly coupled. The large size is a problem due to its intensive computation when on-line optimisation and real-time control are necessary. Thirdly, the SMB unit operation exhibits complex dynamics. Process metrics for design and operation can be determined only when a cyclic steady state is reached after a certain number of switching. Achieving this steady state by solving the PDE models cycle after cycle involves expensive calculation. Studies have been carried out to solve these problems through process analysis, investigation on spatial discretisation techniques, and development of an accelerated integration scheme.
Through a systematic study on the advances of SMB modelling, design and control, a set of functionally equivalent models for SMBCP are identified and summarized for their practical applications. The limitations of the existing modelling techniques in industrial applications are also identified. Furthermore, structural analysis of the existing models is conducted for a better understanding of the functionality and suitability of each model. Suggestions are given on how to choose an appropriate model with sufficient accuracy while keeping the computational demand reasonably low for real time control.
Effort is made on to the systematic investigation of different numerical methods for the solution of PDEs to circumvent the steep gradients encountered in chromatographic separation. Comprehensive studies are conducted on a single column chromatographic process represented by a transport-dispersive-equilibrium linear model. Numerical solutions from the upwind-1 finite difference, wavelet-collocation, and high resolution methods are evaluated by quantitative comparisons with the analytical solution for a range of Peclet numbers. It reveals that for a PDE system with a low Peclet number, all existing numerical methods work well, but the upwind finite difference method consumes the most time for the same degree of accuracy of the numerical solution. The high resolution method provides an accurate numerical solution for a PDE system with a medium Peclet number. The wavelet collocation method is capable of catching up steep changes in the solution, and thus can be used for solving PDE models with high singularity.
The advantages and disadvantages of the wavelet based approaches are further investigated through several case studies on real SMBCP system. A glucose-fructose separation process is firstly chosen with its relatively simple isotherm representations. Simulations are conducted using both wavelet collocation and upwind finite difference methods. For more complicated applications, an enantiomers separation process is selected. As the PDEs model exhibit a certain degree of singularity, wavelet collocation and high resolution methods are adopted for spatial discretisation. It is revealed that both the wavelet based approaches and high resolution methods are good candidates in terms of computation demand and prediction accuracy on the steep front. This is the first time that these two frontier numerical methods are used for such a complex SMB system models and our results are encouraging for the development of model-based online control scheme.
In developing a new scheme to rapidly obtain the solution at steady state for any arbitrary initial condition, the concept of Quasi-Envelope (QE) is adopted under the consideration that a SMBCP can be treated as a pseudo-oscillatory process because of a large number of continuous switching. The scheme allows larger steps to be taken to predict the slow change of starting state within each switching. Combined with previously developed wavelet-based technique, this method is successfully applied to the simulation of a SMB sugar separation process. Investigations are also carried out on the location of proper starting point for the algorithm and on the effect of changing stepsize to the convergence of iteration method. It is found that if the starting state of Quasi-Envelope is chosen to be the same as the original function, the multivalue algorithm would require similar computational effort to achieve the steady state prediction, regardless of the integration stepsize. If using constant stepsize, launching QE later is helpful when quasi-envelope displays steep change at the start-up period. A changing stepsize produces slow convergence compared to the constant stepsize strategy, thus increasing the work load where the stepsize change is occurring. Other iteration method is required to be imposed to achieve faster convergence right from the beginning. Potential applications can be seen for other chemical engineering processes with inherent cyclic behaviour.

Tese de doutoramento em Engenharia Química e Biológica
A presente tese teve como objectivo principal a recuperação de fructo-oligossacarídeos (FOS) de misturas de açúcares obtidas por fermentação. Entre as técnicas de separação actualmente disponíveis, a cromatografia líquida foi o método escolhido. Duas fases estacionárias foram estudadas, nomeadamente o carvão activado e várias resinas de troca iónica. A adsorção/dessorção de FOS contidos numa mistura de caldo de fermentação, usando um gradiente de água/etanol, foi estudada numa coluna de carvão activado. Após optimização do método foi possível recuperar 74.5% (p/p) de FOS em relação aos FOS inicialmente contidos no meio de fermentação. Adicionalmente, obtiveram-se fracções com graus de pureza até 97% (p/p). Este método mostrou ser também foi eficiente na dessalinização do caldo fermentativo. O método de separação usando a coluna de carvão activado foi um bom ponto de partida para a obtenção de grandes quantidades de FOS puros de uma forma simples e pouco dispendiosa. No entanto, o principal objectivo desta tese consistia no desenvolvimento de um processo de separação para ser usado numa escala industrial, portanto, economicamente atractivo. Assim, a técnica de cromatografia de leito móvel simulado (SMB) foi seleccionada como sendo o método de separação mais adequado. A cromatografia de SMB tem a vantagem de trabalhar de um modo contínuo, usando água como eluente e fases estacionárias homogéneas, levando a resultados muito reprodutíveis. Como tal, estudaram-se várias resinas de troca iónica com potencial suficiente para serem utilizadas numa planta piloto de SMB. A adequação das resinas na separação de mono- e dissacarídeos foi avaliada através dos estudos de equilíbrio de adsorção, cinética e de resistência mecânica. A resina seleccionada foi uma Dowex Monosphere 99K/320, tipo gel, com 320 mm de diámetro das partículas, em forma de potássio. Estabeleceu-se um modelo matemático para descrever a eluição cromatográfica do caldo fermentativo em coluna e identificaram-se os parâmetros cinéticos e de adsorção. Os FOS foram purificados com sucesso de 37.1 a 62.9% (w/w), usando o SMB. Além disso, o rendimento e a produtividade obtidos para FOS no refinado atingiu 69.4% (w/w) e 82.1 g.L-1.h-1, respectivamente. Até agora, nenhum trabalho científico reportou a recuperação de FOS de caldos fermentativos utilizando o SMB. Com a grande expansão do mercado de FOS na última década, devido ao crescente interesse dos consumidores por alimentos saudáveis, os resultados obtidos nesta tese mostram-se muito promissores para a indústria alimentar, nomeadamente no desenvolvimento de novos processos para a recuperação de açúcares produzidos por processos fermentativos.

博士
高雄醫學大學
藥學研究所
90
Part I To deal with original identification of Cnidii Fructus, to exploit separation of osthol , and to examine their anti-Trichomonas vaginalis effects and pessary preformulation are the main purposes of this study. We used X-Ray powder diffraction (XRPD) to enhance the original identification, distilled osthole from Cnidii Fructus by vacuum distillation. A Coulter® counter, flow cytometer and microscope, were used to determine the anti-Trichomonas vaginalis effect of the herbal medicine in vitro. We also evaluated the stability and physical-chemical properties of the hydrophilic and hydrophobic excipients as Cnidii Fructus and osthole pessary bases. XRPD was useful to distinguish Cnidii Fructus and its replacements. Cnidii Fructus from the southern and northern parts of mainland China could be distinguished by osthole assay from chromatography and the specific XRPD peak of osthole could also be taken as a usage basis. Osthole was distilled from Cnidii Fructus extract by vacuum distillation. When compared to traditional technique (column chromatography method), it is economic, rapid, high-yield and low pollution. Osthole and xanthotoxol were the ingredients of Cnidii Fructus for inhibiting Trichomonas vaginalis and the minimum inhibition concentration was 0.25 mg/mL. Other constituents like bergapten and isopimpinellin were found to have no inhibition effect against trichomonas. The Cnidii Fructus extract pessary was less stable than osthole pessary. The stability was in rank order, polyethylene glycol >= cocoa butter > Suppocire® > glycerinated gelatin. Polyethylene glycol and cocoa butter should be the better choice for pessary formulation. Part II The purpose of this investigation was to determine the possible interaction between four excipients (lactose, corn starch, Emcompress® and Avicel PH 101â) and the indicating standards (n-butylidenephthalide, n-butylidenephthalide, atractylon, paeoniflorin, luteolin, aconitine, methyleugenol, amygdalin and cinnamic acid) of Radix Angelicae, Rhizoma Chuanxiong, Rhizoma Atractylodis, Radix Paeoniae, Medulla Junci, Radix Aconiti, Herba Asari, Semen Armeniacae and Ramulus Cinnamom, respectively. Extracting efficiencies of herbal medicine for various solvent systems were compared. Samples for accelerating test were prepared by mixing equal amount of the herbal extract and the four respective excipients and stored at elevated temperature and humidity conditions. A differential scanning calorimetry (DSC) was employed to determine the possible interaction between excipients and indicating standards. Ethanol was a better solvent for extracting Radix Aconiti and Herba Asari. For Radix Angelicae Sinensis, Rhizoma Chuanxiong, Rhizoma Atractylodis, Radix Paeoniae, Medulla Junci, Semen Armeniacae and Ramulus Cinnamomi, the ethanol /water（1/1） solution was more efficient than ethanol. Corn starch is the better choice for Radix Angelicae, Radix Paeoniae, Medulla Junci and Radix Aconiti, While Avicel PH 101â is the better choice for Rhizoma Chuanxiong and Rhizoma Atractylodis. There are no obvious difference existing in excipients and indicating standards of Herba Asari, Semen Armeniacae, Ramulus Cinnamomi. According to the DSC profiles, corn starch and Avicel PH 101â seem to have no interaction with indicating standards. The results also indicate that interactions between aconitine and lactose, and between Emcompressâ and four other indicating standards, n-butylidenephthalide, atractylon, paeoniflorin and cinnamic acid were possible. High temperature and humidity are crucial to the stability of indicating components of herbal medicine, especially for preparations containing essential oil. Therefore, choices for excipients in herbal medicine formulation should be cautious. Keywords: Rhizoma Atractylodis；Radix Paeoniae；Medulla Junci；Radix Aconiti, Herba sari；Semen Armeniacae；Ramulus Cinnamom；