Waste and biomass are considered to be an important fuels and renewable energy resources to construct a sustainable society in Japan. However, there are concerns about economic competitiveness and compliance of environmental regulations. There is few engineering and economic analysis for the emerging “green energy” industry in the literature. This paper deals with the evaluations for public policy and private enterprise that require a resource supply analysis that including both costs and impacts to the environmental pollutions. We use engineering cost estimates and econometric modeling taking into account local variation in cost-determining factors such as waste & biomass contents, competition from alternative supplier, geographic density in the region and compliance of environmental regulations. Then using our estimates, we develop an optimal technological choice model and apply to prefecture-level data in Japan. Our results show that waste and biomass are more important energy source than previous estimates.

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This study is discussed water purification and leaching ability of tidal flats sediment in Ishaya Bay Site .Water purification ability evaluate as decreasing of previously adjustment of nitrogen, phosphorus concentration in synthetic sea water using batch experiments. First of all, the factor of water purification ability is classed using compared sediment and sterilized sediment Ammonia was decreased by microbiological activities, and nitrate was decreased by microbiological activites and absorption, phosphorus decreased by absorption. Dentrification and Nitrification can applied Line weaver-Burk equation , decreased of Nitrate and phosphorus can applied Feundlich equation. Maximum denitrification and nitrification are 10.79 and7.24 µg/(g d), respectively. Effect of salinity on denitrification rate is bigger than nitrification rate. Secondly, leaching ability was examined using column experiment when 3.4% and 1.7% salt synthetic sea water. The ammonia concentration increasing with time, after that it's nitrified to nitrate.

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The methodologies and results of CO₂ fluxes measured on an arid land of Sturt Meadows in Western Australia are described here. There, we selected two measurement places .One was a small forest of Eucalyptus trees (14 meters height as average) and the other was an afforestation trial site where trees were sparsely planted. The CO₂ fluxes were measured by a stationary measurement method with a tower and also an airborne measurement method with a small aircraft. Both methods employed an eddy covariance technique. The CO₂ uptake rates by the small forest on a clear mid-day were 12-17 µmol/(m²·s) from the stationary tower measurement when the soil water content was high. These values agreed well with those obtained from the airborne measurement. The CO₂ uptake rate, however, decreased with decrease in the soil water content even though the solar radiation increased. The soil water content has a great influence on the CO₂ uptake rate in the arid region, and the dependence of the CO₂ flux on the solar radiation depends on the soil water content. The measurement results on the sparse forest also indicated that both measurement methods estimated similar values of CO₂ flux. These results suggest that the airborne method developed can be an efficient method to quantify CO₂ fluxes over various vegetation areas in the heterogeneous arid region, where a measurement tower is hardly built. However, a sophisticated foot-printing analysis is needed to specify the source region of the CO₂ flux.

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The systematic and quantitative approach on the environmental pollution is a significant challenge in highly regulated industries, such as power plants, where a large amount of waste gas including greenhouse gas must be discharged. We propose a novel methodology that was verified various CO₂ reduction processes using simulation. In this study, an environmental pollution impact is explained by the process operating conditions. With PEI(Potential Environmental Impact) representing the environmental impact quantitatively, the estimation of CO₂ reduction processes becomes simplified. For the estimation, this study at first simulated the power plant including CO₂ reduction process. As fundamental data of this simulation, there are operation data of the power plant, data for CO₂ reduction processes, CO₂ reduction rate etc. Finally the efficiency of each CO₂ reduction process is estimated by total PEI Index. Also, the optimal operation condition to reduce CO₂ emission of each process was estimated too. As the result of this study, the suitability of each CO₂ reduction process and the optimal operating conditions of CO₂ reduction processes for a power plant was evaluated.

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A short-term steady state Gaussian-based air pollutant dispersion model has been developed and named HAWA. It is based on the U.S. Environmental Protection Agency (USEPA) Industrial Source Complex Short Term 3 (ISCST3) model. This model was developed to evaluate pollutant concentrations from elevated point sources (e.g. stacks) up to 10 sources in moderate terrain. HAWA generates text file and Matlab® file as output. Microsoft© Visual C++® 6.0 was used in writing the model in contrast to FORTRAN that was used to program ISCST3. The former was used to develop a user-friendlier model compared to other models that are difficult to use. Three configurations are modeled using HAWA. Stacks of different heights aligned along the x-axix, y-axis, in L vonfigurations produced different pollutant distribution trend, which illustrates the significant relation of stack height to pollutant dispersion of multiple stacks. Based on three stacks configuration, 50 m stack height for all 3 stacks will likely cause the highest ground level concentration of pollutants while 100 m stack for all three stacks will cause the lowest. Distnce of 500 m between same stack heights (aligned along the x-axis) is enough to not mix the pollutants coming from each stack, at least not at high concentration (>10 µg/m³). Closer distances warrant the stacks to have proper stack height (twice the height of a lower stack). The concentration of pollutants from a stack directly behind an upwind stack will add up to the pollutants emitted by the stack in front resulting in higher concentration downwind (aligned along the y-axis). It is advisable then to have a stack configuration where the either of the inline stacks is higher (2 times the height of the shorter stacks) than the other stack or both stack designed using the best stack height. All three stacks of same stack height (except very tall stacks) in-line will cause the highest ground level concentration, so this type of stack configuration is undesirable.

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In Malaysia, Integrated Project Planning has been used widely and it implies that environmental impact assessment should be continuous process throughout the course of project planning. The construction and operation of a dam has been predicted to have significant environmental impacts. This paper reviews the management actions and activities undertaken for the construction of Beris Dam from documented sources i.e. EIA, EMP, monitoring reports and independent audit reports. The management activities were discussed according to the project phases: pre-decision, post-decision and transitional stages. The analyses reveal that management actions and activities were important in distinctive ways in all three stages of EIA process. This study noted the importance of integrated project management and environmental management from project inception until operation. The full benefits of this integrated project planning will ensure sustainable development in Malaysia.

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A compact artificial gill was developed using a concentrated hemoglobin solution containing inositol hexaphosphate (IHP) as the oxygen carrier solution. Oxygen dissolved in seawater is first taken up from water to the oxygen carrier solution at 293 K. The oxygen carrier solution is then heated and the oxygen is released from the oxygen carrier solution to expired air at 310 K. The enhancement factors of oxygen carrier solution that indicates its performance were approximately 3 for the oxygen uptake and 16 for the oxygen release, respectively. The scaling up for a human at rest was estimated. The required membrane surface area and seawater flow rates were 63.8 m² and 0.00653 m³/s, respectively. These values indicate the feasibility of a compact and portable artificial gill for human underwater activity.

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For a development of a hybrid artificial liver, it is important to express liver specific functions at a high level, and to accomplish long-term maintenance of these functions. It has become clear that hepatocytes, which have a form of tissue-like structure (hepatocyte organoid), can express highly differentiated functions. In this study, we developed a novel module, which applied our original hepatocytes organoid culture technique using centrifugal force. And we investigated the performance of this module as a hybrid artificial liver.
The module consists of many hollow fibers arranged regularly at submillimeter order by spacers. Rat hepatocytes of 5.9 X 10⁷ in number were immobilized inside or outside hollow fibers by centrifugal force. Each hollow fiber and its surrounding hepatocytes seemed to reconstruct a unit structure of a liver-lobule. The module performed perfusion culture and liver specific functions were evaluated.
Hepatocytes immobilized in the module formed an organoid surrounding hollow fibers with lotus-root shape. The hepatocyte organoid could express liver specific functions at high level, and maintain these functions for about 3∼5 months of culture. To evaluate as an artificial liver, the module was applied to a hepatic failure rat. The module was effective in supporting liver function and recovery from liver failure state. These results indicate that this novel module may be useful to treat liver failure patients until regeneration of the native liver.

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The diffusional drug release from matrix-type devices have numerically been solved for various drug delivery systems. The present matrix-type drug delivery systems include the devices which the drug loading is higher or lower than the solubility in the polymeric matrix. In the former system, a moving boundary problem is treated because the position of diffusion front, the boundary between dispersed and dissolved zone in the matrix, changes with time. In this study, we have solved the release kinetics from matrix-type devices containing dissolved or dispersed drug using a finite difference method for partial differential equations under various conditions. The present mathematical model can also analyze the diffusion boundary layer formed on the surface of the device and the sink or non-sink condition in the receptor compartment.

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Vitreoscilla hemoglobin (VtHb) has been expressed in Saccharomyces cerevisiae, and its influence on yeast growth has been investigated. An expression vector was constructed to express VtHb under the control of GPD promoter and GAL7 terminator. The expression of a VtHb gene (460 bp) and a protein product (15.8 kDa) in recombinant strain was shown by colony PCR and Western blot analysis, respectively. Batch cultivations were performed at 30°C and 200 rpm with a constant air flow rate of 2 vvm in YEPD medium until 48 hr. The recipient strain showed a typical sigmoidal growth curve with the entry of stationary phase after 9 hr of cultivation. However, the recombinant strain exhibited the continuous growth until 26 hr and it reached the cell density of O.D. 19 at 600 nm, which corresponded to 50 % increase of cell mass compared with the recipient strain. These results suggest that the yeast strain can be engineered to have better growth even in the oxygen limited condition by the expression of VtHb.

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Novel technologies to establish 3D constructs consisting of homotypic or heterotypic cells are desired for tissue engineering. In the present study, both of magnetic force and magnetite nanoparticles were used to construct a homotypic layered human keratinocyte sheet and a heterotypic layered co-culture system of rat hepatocytes with human aortic endothelial cells (HAECs). Magnetite cationic liposomes (MCLs) originally prepared by us, which have a positive surface charge in order to improve adsorption by cells, were taken up by the target cells (human keratinocytes or HAECs). Magnetically labeled target cells incorporating magnetite nanoparticles, specifically attracted at sites where a magnet (4,000 Gauss) was positioned, and then adhered to form homotypic keratinocyte sheets with 5-10 layers or heterotypic-layered co-culture of HAECs with hepatocytes 3D with tight and close contact. These results suggest that this novel use of magnetite nanoparticles and magnetic force, which we refer to as "Magnetic force-based tissue engineering (Mag-TE)", offers a major advancement in tissue engineering.

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Granulocyte-macrophage colony stimulation factor (GM-CSF) is a cytokine that stimulates the production of granulocytes, macrophages and white blood cells. Production of recombinant hGM-CSF was studied in rice cell secretory expression systems. In rice cell suspension culture, we used a rice amylase expression system in which the promoter RAmy3D is induced to express hGM-CSF by sucrose starvation. The drawback of this system is that the cells have to synthesize the recombinant protein without a carbon source, and thus improvements of culture condition for the recombinant protein production are desire to increase its productivity by addition of alternative carbon sources, such as succinic acid, pyruvic acid, malic acid, and fumaric acid. In addition, the viability of rice cells were higher. Succinic acid was the most effective alternative carbon source for the production of hGM-CSF. The accumulated hGM-CSF in the medium containing 80 mM succinic acid reached 165 mg/L at 15 days in batch culture while that in the control medium was 120 mg/L. These results show that the hGM-CSF prouctivity was increased from 12.8 % to 35.4 % by supplying the alternative carbon sources.

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We developed a new hybrid artificial liver (HAL) module including hepatocyte spheroids that formed in pores of polyurethane foam (PUF). The efficacy of our HAL was evaluated by applying to the liver failure pig in preclinical experiments. We designed a multi-capillary PUF (MC-PUF) module containing 1 x 10¹⁰ porcine hepatocytes. In a preclinical study, the PUF module was applied to a pig of 25 kg pig warm ischemic liver failure (HAL group, n=3). The same system without hepatocyte in the module was also applied to the liver failure pig as control (Control group, n=3).In the control group, the blood ammonia rapidly increased up to 1028 N-µg / dl in 12 h. On the other hand the increase in blood ammonia was suppressed below the hepatic coma level of 200 N-µg / dl in the HAL group. Curative effects such as maintenance of the fisher's ratio, blood gluconeogenesis, suppression of the increase of blood lactic acid, stabilization of the vital signs and urinary excretion were also observed in the HAL group. The average survival time in the HAL group was extended to 19.3 h from 8.9 h of that in the control group. In conclusion, we successfully developed the original HAL to be applicable to a treatment of a liver failure patient.

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Bioartificial liver (BAL) is an extracorporeal liver support system, which contains biological components such as hepatocytes as a biocatalyst. The BAL will act as a bridge to provide patients with the extension of survival time until a donor organ becomes available for transplantation or their own liver can be regenerated. The performance of a BAL depends on the functional activities of the hepatocytes immobilized in the system. However allogenic hepatocytes from human livers are poorly available, so xenogenic hepatocytes, usually porcine hepatocytes have been used in BAL. The cells are immobilized as a form of single cells or spheroids inside the beads. But the efficient culture technology to form a lot of hepatocytes, 1x1010 cells into spheroids in large scale is not yet developed. The reasons are oxygen limitation and shear stress in large volume of suspension vessel. We achieved a high viability and functionality of porcine hepatocyte spheroids through application of simple modification of media without any addition of apparatus. As in vitro and in vivo results, we could recover enough spheroids and these cells showed high ammonia removal capacity in preclinical treatment of anhepatic pig.

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Usual cytotoxicity tests do not include various metabolic processes such as absorption from the small intestine or biotransformation in the liver and small intestine in humans. We therefore developed a physiologically based perfusion coculture system using a Caco-2 and Hep G2 cells; the former was used as a representative of the small intestinal membrane and the latter was used as the liver tissue. Such perfusion cocultivation enhanced the growth of Hep G2 cells and the cytochrome P450 1A1/2 capacities of both cell lines. When benzo[a]pyrene (BaP) was introduced as a model toxicant to the apical side of the Caco-2 cell layer, the enhanced P450 capacities produced a larger amount of BaP-7,8-hydrodiol, an immediate precursor to the highly reactive ultimate toxicant of BaP, BaP-7,8-dihydrodiol-9,10-epoxide. Although such BaP metabolites were preferably secreted back into the apical side of the Caco-2 membrane, the enhanced production of BaP-7,8-hydrodiol led to initially retarded and later stronger expression of BaP toxicity in the coculture system than in pure culture. This kinetics of the toxicity agreed well with the largest time integral of the concentration of BaP-7,8-hydrodiol in the Hep G2 cell compartment. Because this system can reproduce such complicated phenomena in vitro, including those derived from organ-to-organ interactions, it is useful as a new cytotoxicity test to help elucidate unknown mechanisms and to develop physiologically based pharmacokinetic numerical simulation models.

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In this report, present status of a project for a process development based on genomics going on in our groups is explained. Goals of the project supported by the New Energy and Industrial Technology Development Organization (NEDO) is to build object-oriented metabolic pathway models which describe metabolic flux change due to the cultivation conditions change such as from normal one to high osmotic pressure (sugar concentration), and also to apply the model for effectively designing an improved strain producing useful compounds which can play important roles for green chemistry. The model will be developed using the data of transcriptome, proteome and metabolites. In the project, the analysis system which was composed of bioreactor system for taking the on-line/off-line data of metabolic flux analysis, NMR analysis system and software system for data mining from transcriptome as well as proteome, has been set up and took data for high sodium chloride concentration as a model of high osmolarity condition. At the same time, three sub-projects have been proceeded; (1) Basic techniques for metabolic engineering in order to control the targeted pathway flux in Saccharomyces cerevisiae have been developed. (2) Profiling data of transcriptome and proteome have been taken at high sodium chloride concentrations. (3) As one of clustering techniques of the profiling data, SOM (self organizing map) has been extensively studied, applied to the transcriptome data obtained in this project. The project has been now on the stage of strain improvement based on the analysis of the genome information.

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Peptides, which consist of small numbers of amino acids covalently coupled with peptide bonds, are known to play functionally significant role through ligand-receptor interaction on cells to modulate various vital reactions, in spite of their small molecular weight and simple structure. With accordance of peptide synthesis technology, a peptide chip, which is a combinatorial solid support-bound synthetic peptide library on membrane, has brought more possibilities into peptide drug discovery researches. We here report, for the first time, the high-throughput peptide screening strategy using peptide chip. From the target functional protein Fas antigen ligand, which is well known as cell death or apoptotic signaling ligand, we found novel functional peptide domain of 5-mers by utilizing the peptide chip system associated with the cell assay method. The obtained peptide showed strong growth inhibition (68% inhibition compared with the control membrane without any binding peptide) to human leukemia Jurkat cell line in the cell viability assay. The growth inhibition effects of obtained peptide to other cell lines, including non-adhesive leukemia cells (A3, I9.2, K562) and adhesive cells (HeLa, 3T3), also revealed to be more than 95% in average. The effect was slightly weakened but showed significant inhibition when the peptide was synthesized as soluble form and applied to the cell viability assay. The advantageous feature of peptide chip screening system is the flexibility of synthesized peptide library, in which we can examine both length effects and amino acid substitution effects on one chip. So we succeeded to design novel 31 peptides with higher cell growth inhibitory effects by altering the original sequence. According to the results, the obtained novel peptides were considered to be candidates of peptide drug, which can induce cell death in cancer cells. Our cell assay system proposed here was also proved to be effective in such drug discovery and design.

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We created Arg-Gly-Asp (RGD) cell adhesive motif encoding repetitive DNA library with overlap elongation PCR method. By this DNA elongation reaction, we obtained various chain lengths DNAs encoding repetitive RGD, and isolated the genes encoding, 21-times and 43-times repeats of RGD motif. We cloned these genes into the protein expression vector, and overexpressed as thioredoxin fusion proteins, RGD21 and RGD43. The solubility of RGD43 in water is low, and RGD43 formed self-assembled fibrous precipite in water. From the scanning electron microscopic observation, it was indicated that RGD43 formed a branched 3D-network structure in solid state. Mouse fibroblast cells were cultivated on RGD43 protein scaffold, it was indicated that the fibroblast cells adhered and extended long filopodia on RGD43 protein scaffold.

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The further understanding of the mechanisms of the budding cell cycle networks requires the comprehensive map for the detailed signal transduction pathways and the integration of huge amounts of post-genomic data (DNA microarray and protein-protein interaction data) into such a map. The use of CADLIVE (1) constructed a detailed map of the budding yeast cell cycle, which consists of 184 molecules and 152 reactions, and integrated postgenomic data into the map by computationally exploring the signal transduction pathways. Consequently, the inconsistency between the detailed map and the post-genomic data greatly facilitated exploring novel or unexpected interactions among different processes. Biological predictions would be facilitated by exploring the interaction among the molecules that are located at distant processes on a map rather than by focusing on local signal transduction pathways intensively.

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To engineer the enantioselectivity of lipase from Burkhorderia cepacia KWI-56, a combinatorial library involving mutations at four amino acid residues in its hydrophobic substrate binding pocket was constructed by SIMPLEX (single-molecule-PCR-linked in vitro expression) and screened for (R)- and (S)-configurations of p-nitrophenyl 3-phenylbutyrate. Some combinations of amino acid substitutions in the four positions of the lipase were found as effective for changing the enantio-preference from the (S)-form substrate to the (R)-form (J. Mol. Biol. 331,585,2003). Here, the relative enantioselectivity and the amino acid residues' data of the obtained 17 variants in the above experiments have been analyzed by knowledge informational analysis using a fuzzy neural network (FNN), in which a rule on the interconnection between inputs and outputs was automatically acquired by learning without any structural information of the protein and the substrate. Hydrophobicity, van der Waals volume and electrical effect of amino acid residue in each position was provided as inputs for the FNN analysis and a set of rules was extracted indicating that van der Waals volume of position 167 has the most significance for the enantioselectivity of the lipase, as well as predicting likely variants that were not found in the actual screening. Then the real construction of such variants has shown that the FNN analysis can figure out the real world of the protein sequence combination space. The collaboration between high-throughput screening and bioinformatic technology has proved to be quite powerful to explore a novel protein with targeted functions from the vast space of protein sequences.

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In nature, curdlan and other β-1,3-D-glucan adopt a right-handed 6₁ triple helix, which is underpinned by the intermolecular hydrogen bonds between the constituent glucoses. Curdlan forms a stoichiometric complex with polynucleotides (e.g., poly (cytidylic acid): poly(C)). We carried out a semi-empirical quantum-mechanics calculation (MOPAC) to speculate a molecular structure for the curdlan/poly(C) complex. The calculation exhibited that two types of hydrogen bonds are formed between the 2nd OH of the curdlan main chain and the cytosine of poly(C). In the calculated model, the conformation of the helix is different from that of the single chain. The helix diameter is expanded from 11.0 to 15.3 Å upon complexation. Despite of the conformational change induced upon the complexation, the 6₁ helix structure of poly(C) in the complex was maintained as the original single chain. This fact agrees with the experimental result that the complexation did not change the circular dichroic spectral shape. The chain length relationship of the reaction enthalpy change indicates that the complexation is more favorable than the decomplexation when the chain of the curdlan/poly(C) complex is long enough.

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Growth properties and gene expression profiles by using slide glass-based DNA microarray under high osmotic pressure condition (addition of NaCl) were compared between the two yeast strains, a laboratory strain and a brewing one used for Japanese rice wine (sake) brewing. Growth properties in both strains after addition of 1 M of NaCl revealed that the brewing strain was more tolerant to osmotic stress than the laboratory one. DNA microarray analysis data indicated that the genes encoding the enzymes involved in acetate, glycerol and trehalose synthetic pathways were up-regulated in both strains under the stress conditions. Moreover, genes encoding sodium ion pump and cupper ion-binding proteins were more up-regulated in brewing strain than in the laboratory strain. Up-regulation of these genes might characterize the osmotic stress-tolerance of the brewing strain. We constructed a glycerol-overproducing strain by expressing GPD1 gene encoding glycerol-3-phosphate dehydrogenase constitutively in the laboratory strain and evaluated the osmotic stress tolerance of this strain. This improved strain showed more tolerant to osmotic stress than the parent strain, but glycerol was immediately exported outside of the cells. We are constructing further improved strain by disrupting the gene encoding glycerol exporter protein and we will evaluate again the stress tolerance of this strain.

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To improve metabolic pathways for enhancement of a targeted product systematically, quantitative systems analysis in bionetworks of gene, protein, and metabolic pathways is highly desired. Quantification of effect of perturbation of genes and proteins on metabolic fluxes enables to elucidate the parameters responsible for the control of flux in metabolic pathways. In this study, mechanism of flux redistribution at a key branch point in glutamate production by coryneform bacteria, Corynebacterium glutamicum and Corynebacterium efficiens is studied. The quantitative analysis at a key branch point, namely, 2-oxoglutarate(αKG), was performed by comparison of flux distribution before and after addition of the triggering operations such as depletion of biotin and addition of Tween 40. The flux redistribution from the central pathway to glutamate synthetic pathway obviously occurred after the decrease in activity of 2-oxoglutarate dehydrogenase complex, ODHC, while activities of other enzymes at the branch point of isocitrate dehydrogenase, ICDH, and glutamate dehydrogenase, GDH, were not significantly changed. The comparative studies on flux distribution of a wild type strain of C. glutamicum and two genetically engineered strains which harbor a plasmid with genes encoding ICDH and GDH, respectively, also reached the same conclusion that the ODHC is the most crucial factor for the control of flux distribution at the 2-oxoglutarate branch point. The difference in glutamate production between C. glutamicum and C. efficiens is due to a result of the difference in the degree of decrease in ODHC activity. A model with kinetic parameters well explained the phenomena of flux redistribution at the 2-oxoglutarate branch point and predicted flux redistribution.

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To control quorum sensing in gram-negative bacteria, several kinds of autoinducer analogues were synthesized and examined their agonistic or antagonistic activities against quorum sensing in gram-negative bacteria. N-acyl-L-homocystein thiolactones acted as agonists and N-acyl-cyclopentylamides acted as antagonists against autoinducers in gram-negative bacteria. Cyclodextrin-autoinducer complex formation was also investigated. The inhibition effects on autoinducer activities of quorum sensing in gram-negative bacteria was observed by adding α- or β-cyclodextrin in the bacterial culture medium, while γ-cyclodextrin showed no effect.

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This article presents a combined neural network/genetic algorithm technique for bioprocess modeling and optimization. The approach is illustrated using a published lipase-catalyzed esterification process as an example. A neural network model is developed on the basis of a small data set obtained from a central composite rotatable design. The experimental design provides information of the influence of five process variables and their interactions on a response variable (ester yield). The performance of the resulting neural network model is compared to that of a quadratic polynomial model. Modeling results show that the neural network can outperform the quadratic polynomial in correlating the data set used in the training of the neural network and regression of the polynomial. Both models however give similar predictions of unseen data. A genetic algorithm is successfully used to identify the optimal settings of the five process variables that result in a maximum ester yield based on the neural network. The combined neural network/genetic algorithm technique can accomplish objectives similar to those of response surface methodology.

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Oxidation experiments of β-carotene were performed in a biphasic oil-water system having a definite interfacial area. An inert solvent, n-decane, and 0.01 M Tris-HCl buffer solutions were used as oil and water phases, respectively. The time for which α-tocopherol remained in the biphasic system was about 1.6 times longer than that in the single phase of n-decane. α-Tocopherol was consumed by its oxidation as well as the antioxidative protection of β-carotene. The peroxyl radical of α-tocopherol concerned with the chain oxidation was easily dissolved in the water. This phenomenon was considered to contribute the restrain of α-tocopherol consumption, resulting in the suppression of β-carotene oxidation. A kinetic model was constructed by considering the transfer of the α-tocopherol peroxyl radical into the water phase in addition to the oxidation and antioxidation mechanisms of β-carotene. The model quantitatively described the oxidation behavior of β-carotene in the biphasic system over wide ranges of temperature, initial α-tocopherol concentration, interfacial area and water phase volume.

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Display of novel enzymes on the yeast cell surface is very powerful method to develop the efficient whole cell biocatalysts, because the diffusion problem of substrate and product is circumvented. In addition, the displayed enzymes are regarded as a kind of self-immobilized enzyme on the cell surfaces. In this study, we have developed the novel methods to display enzymes using cell wall anchoring proteins -agglutinin. To show their applicability to the productions of biofuels and chemicals from biomass, the ethanol production from cellulosic materials was investigated by using yeast cells displaying cellulolytic enzymes. Due to the display of these enzymes, cellulosic materials were sequentially hydrolyzed to glucose on the yeast cell surface, immediately utilized and converted to ethanol by intracellular enzymes. The yield in terms of grams of ethanol produced per grams of carbohydrate utilized was over 0.45, which corresponds to over 89% of theoretical yield. These results demonstrate that a combination of cell surface displayed enzymes and intracellular metabolic system is a very effective approach to develop cells with novel catalytic and metabolic abilities for industrial applications.

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A liquid-core alginate-membrane capsule was prepared by a novel method using polyethylene glycol (PEG) as a thickener. In the proposed method, the residual thickener PEG in the capsule was able to leak through the alginate shell membrane. This results in low-viscosity of the core liquid enabling good mass-transfer performance, whereas xanthan gum as a thickener could not leak through. In addition, the intra-capsular mass-transfer characteristics of glucose as lower molecular weight substance and proteins as higher molecular weight substance were investigated. An apparent effective diffusivity of glucose into the capsule was larger than that into alginate beads and in water. Moreover, an encapsulation of strawberry cells in the capsule did not cause a decrease in the mass transfer performance of glucose contrary to the cases of immobilization in alginate beads or the capsule using xanthan gum. On the contrary, the apparent effective diffusivities of proteins from the capsule utilizing PEG were smaller than those in alginate bead. Next, the cells of Saccharomyces cerevisiae were encapsulated in its core and cultured. After 24 h of cultivation, the cell concentration in the capsule core-liquid reached 222 µg/mm³ on a dry weight basis, which was 1.4 times as large as that in the core of double-layered alginate beads, i.e.., alginate-coated alginate-gel beads. The diameter increase of the capsule prepared by the proposed method using immobilized cell growth was suppressed compared to those using the double-layer method and simple alginate-gel bead entrapment, most likely because of the mobility of the entrapped cells in the capsule. Finally, an electrostatic force was applied to miniaturize a liquid-core alginate-gel membrane capsule prepared with PEG. At an applied potential of 5 kV using a 27-gauge needle, the capsule diameter was successfully decreased to 680 µm, which was a fifth of the initial size without electrostatic atomization.

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Polyelectrolyte complex gel beads have been used for wide-spread application, including use in medical, pharmaceutical, and bioengineering fields. Many of these applications of polyelectrolyte complex gel beads require narrow size distribution as well as strict control of particle shape. A calcium alginate beads or an alginate poly-L-lysine alginate system is the most commonly employed system in these polyelectrolyte complex systems. In this study, we demonstrated novel method for preparing monodispersed calcium alginate beads with small diameter (less than 300 µm) using microfabricated nozzle (MN) array. The MNs with an inner witdth of 30 x 30 µm and outer witdth of 60 x 60 µm were fabricated by photolithography and deep reactive ion etching process. Alginate droplets with narrow size distribution were formed by extruding the alginate aqueous solution into the flow of soybean oil through MNs. Monodispersed alginate droplets with an average diameter of 88.4 µm and a coefficient of variation of 5.9% were formed from MNs. The CaCl₂ droplets were formed in the same manner at the downstream of the soybean oil flow. Calcium alginate beads were prepared by the immediate contact between alginate droplets and CaCl₂ droplets. Most of the prepared beads had spherical shape. The number-average diameter and coefficient of variation of the prepared beads was 77.4 µm and 11.1%. The method proposed in this study is expected to be applicable for the various polyelectrolyte complex systems.

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Haematococcus pluvialisis is one of the potential candidates for production of astaxanthin. Growth characteristics of H. pluvialis in batch run and medium replacement runs were measured. A two-stage process was employed for biomass and astaxanthin synthesis by this alga. During the first stage, medium was replaced several times every day to achieve high cell concentration. When the replacement was stopped, the light illumination was switched from red LEDs at 8μmol photons m^-2 s^-1 to blue LEDs at 12µmol photons m^-2 s^-1 to stimulate the accumulation of astaxanthin without decreasing in the cell numbers by death of the cells. H. pluvialis exhibited relatively high cell concentration in the first step and reached to about 1.5 mg-dry cell/cm³ and accumulated up to 65 µg/cm³ astaxanthin in the second stage, which are higher than those reported in literature.

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It is one serious problem that high sugar concentration at an initial phase and/or accumulation of product during cultivation causes osmotic stress to cells in fermentation process using yeast, Saccharomyces cerevisiae. In this study, we analyzed the protein expression of yeast using two-dimensional electrophoresis under a high osmotic pressure condition and investigated the physiological change in yeast cell. A laboratory strain FY834 and brewing one IFO2347 were grown in YPD medium. High osmotic pressure condition was prepared by adding NaCl at final concentration of 1 M in mid-log phase. Although the growth of FY834 was stopped and that of IFO2347 was decreased, the growth of both strains was recovered later. The period between addition of NaCl and recovery of growth was 4 hours for FY834 and 2 hours for IFO2347, respectively, indicating that IFO2347 was more tolerant to osmotic stress than FY834. Protein samples were extracted from cells before and after adding NaCl and applied to two-dimensional electrophoresis. Protein expression of FY834 compared to the sample before addition of NaCl was changed after 30 min from adding NaCl, while that of IFO2347 was changed after 15 min. These results suggest that IFO2347 responds more quickly to osmotic pressure than FY834. From the view point of the metabolic pathway, the expression of proteins related to glycerol synthesis were increased after addition of NaCl in both strains, suggesting that yeast strains adapt to high osmotic pressure by synthesis of glycerol. It was consistent to the results of metabolic flux analysis.

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We developed two convenient methods for synthesis homogeneous DNA-protein conjugates. The methods are based on native chemical ligation that allows chemoselective joining of two unprotected molecules via a stable amide bond. Reagent 1 and 2 were synthesized for oligonucleotides modification with a cysteine and thioester, respectively. The amino functionalized oligonucleotides in various length and sequence were successfully converted to oligonucleotides carrying a cysteine or thioester group with new reagents. Recombinant green fluorescent protein carrying thioester group at C-terminus were expressed using intein-tag as model protein. Judging from the SDS-PAGE and MALDI-TOF-MS analysis, the oligonucleotide functionalized with 1 were successfully site-speficically ligated with C-terminus of the protein. The oligonucleotide modified with 2 can joined to recombinant protein that carrying cysteine at N-terminus. Our approach to construct homogeneous protein-DNA conjugate would provide a powerful method in the field of nano-bio technology.

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The display of peptides on the capsid of bacteriophage has become very attractive for a variety of applications. A previously isolated T-even-type PP01 bacteriophage was used to detect its host cell, Escherichia coli O157:H7. The phage small outer capsid (SOC) protein was used as a platform to present a marker protein, the green fluorescent protein (GFP), on the phage capsid. GFP was introduced into the C- and N- terminal regions of SOC to produce recombinant phages, PP01-GFP/SOC and PP01-SOC/GFP, respectively. Fusion of GFP to SOC did not change the host range of PP01. On the contrary, binding affinity of the recombinant phages to the host cell increased. Adsorption of the GFP-labeled PP01 phages to the E. coli cell surface enabled visualization of cells under a fluorescence microscope. The coexistence of insensitive E. coli K-12 (W3110) cells did not influence the specificity and affinity of GFP-labeled PP01 adsorption on E. coli O157:H7. Ten min incubation with GFP-labeled PP01 phage at MOI=1000, 4°C, visualized E. coli O157:H7 cells under fluorescence microscopy. The GFP-labeled PP01 phage could be a rapid and sensitive tool for E. coli O157:H7 detection.

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Seventy three toluene-utilizing bacteria were isolated from soil and activated sludge samples. Among them, eleven isolates were highly tolerant to toluene. One of the toluene-tolerant isolates, designated T-57, was identified as P. putida. Strain T-57 showed tolerance to organic solvents whose log P_ow was equal to or greater than 2.3. Genetic analysis revealed that T-57 possesses the toluene dioxygenase operon. The cis-toluene dihydrodiol dehydrogenase gene (todD) mutant of T-57 was constructed by the gene replacement technique. The todD mutant accumulated o-cresol (maximum 1.7 g/l in the aqueous phase) when it was cultivated in the minimal salt medium supplemented with 3% (vol/vol) toluene and 7% (vol/vol) 1-octanol. Thus, T-57 was thought to be a good candidate of the host strain for bioconversion of hydrophobic substrates in the two-phase (organic-aqueous) system.

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An alcohol dehydrogenase from the hyperthermophilic archaeon Aeropyrum pernix was activated by water-immiscible organic solvents. This activation was influenced by the kind and the concentration of the added organic solvents. V_max was increased more than ten times, when the mole fraction of acetonitrile was 0.1. This effect was large when the organic solvents with the large log P value were added. In fact, V_max showed a strong positive correlation with the log P value of the mixed solvent at the same mole fraction of water, while it was not affected by the kind of organic solvents added. The activation energy was decreased with the increase of the log P value of the solvent. This means that increasing of the log P value is more effective in lower temperature. Consequently, increasing of the log P value by organic solvents is a useful method to use thermophilic enzymes, which are less active at room temperature.

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This study examines the water purification by cylindrical wetted-wall reactor using gas corona discharge. In this reactor, a cylindrical anode and a wire cathode are set apart from each other coaxially in an atmospheric air to generate corona discharge. This reactor is improved by modification from the previous plate anode to the present cylindrical anode. It is expected that reactive radicals produced in a plasma region around a wire cathode in a gas phase can efficiently reach the surface of a falling-water film on the cylindrical anode so that reactive species such as an OH radical can be effectively produced in water. In this study, aqueous phenol was decomposed using the cylindrical-anode reactor to evaluate its efficiency. As a result, the electron efficiency and energetic efficiency of the present reactor were respectively 2-3 and 3-4 times higher than those of the previous plate-anode reactor. In addition, the energetic efficiency per radical-producing plasma region length of the present reactor was 2 orders higher than that of the previous reactor. The experiments were carried out in variety of conditions in which water flow rates, discharge currents, radius of cylindrical anodes, were varied. In addition, the removal processes of phenol and byproducts in these experiments are modeled with numerical simulation based on their oxidative reactions.

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The role of catalyst and the reason for the formation of N2 as a preferential product in the oxidation reaction of aqueous ammonia (NH₃(aq.)) over Ru/TiO₂ catalyst was elucidated. The catalyst was responsible only for the oxidation of aqueous NH₃, finally giving a molecule of nitrous acid. An oxidation reaction pathway was proposed as follows: Oxidation of ammonia in water was initiated by the reaction of NH₃(aq.) with catalytically activated oxygen. After undergoing further successive oxidation reactions with activated oxygen, NH₃(aq.) was finally converted to a molecule of nitrous acid, which, in turn, dissociated into a nitrite ion and a proton. The concentration of NH₄⁺ in solution increased in accordance with the decrease of the solution pH by the HNO₂-dissociated protons. Molecular nitrogen was formed from the homogeneous aqueous phase reaction between NH₄+ and NO₂- ions such produced. Further reaction of NO₂- with the catalytically activated oxygen led to the formation of nitrate ion as another final product. The ionic reaction of NO₂- with NH₄⁺ was accelerated above 100°C, and kinetically more rapid than the oxidation reaction of NO₂- with the catalytically activated oxygen as long as NH₄⁺ was available in the solution.

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Effective removal of hexavalent chromium, Cr(VI) from aqueous solution by adsorption on the used black tea leaves (UBTLs) as a low cost adsorbent has been reported. In the present study, kinetic investigations were carried out to study the transport mechanism of Cr(VI) ion to the UBTLs during the removal process. Adsorption of Cr(VI) on the UBTLs would include diffusion of Cr(VI) from the bulk solution to the surface of the UBTL, adsorption, intraparticle diffusion and chemical reaction. Different transport models were applied to find out the controlling transfer process of Cr(VI) uptake by the UBTLs. The experimental data obtained from the batch treatments show that the Cr(VI) uptake occurs rapidly in the first day, followed by a slow uptake process for about 15 days. A significant effect of particle size of the UBTLs on the adsorption rate indicates the following: the first rapid step and followed slow step of adsorption in this system are controlled by chemical reaction and the intraparticle diffusion, respectively. A parabolic diffusion model suggested that this adsorption mechanism shifts from the reaction controlled to the diffusion controlled with an increase in initial Cr(VI) concentration in the solution. Non-linearity of the ln(C_t/C_o) vs. t plot indicates that the film resistance is insignificant to the transfer of Cr(VI). The intraparticle diffusion is the rate-determining step in the uptake of Cr(VI) by the UBTLs.

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Several metal ions were tested for their adsorption on crosslinked pectic acid gel, where the selectivity order of some metal ions existing as cationic species in water were as follows: Ce(IV) > Ti(IV) ∼Zr(III) >Fe(III) ∼La(III) ∼Cu(II) >Ce(III) >Al(III) ∼ Zn(II). Some of them were loaded on the pectic acid gel and tested for As(V) removal by batch wise adsorption test, whereas, Fe(III)- and Ce(III)- loaded crosslinked pectic acid gels were employed for batch as well as column adsorption test at pH ca. 2. as these gels showed the maximum adsorption capacities for As(V) as high as 0.61 mol/kg and 0.68mol/kg-dry gels, respectively. The study also revealed that Zr(IV) would be remarkably competent metal ion to be adsorbed on pectic acid gel. The adsorption of As(V) on the metal loaded gel tested in this study were found to be unaffected by other anions like chloride, sulphate or both. On the other hand, elution was also found to be successful using either 1M HCl or strongly alkaline solution. Thus, pectic acid, consequently, could offer promising technology for removing As(V) effectively from aquatic environment.

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Several methods for removal of microcystins from water are investigated. Firstly, the variations of the microcystin concentrations in the water of Taihu Lake and in the tap water of Wuxi city during the summer time are discussed. Secondly, two types of photocatalytic reactors are tested. In the annular-flow photocatalytic reactor with a 6-W blacklight blue fluorescent lamp as a light source, three liters of 1600 ppt microcystin-LR solution was treated and 65 % of microcystin-LR was degraded after 3.5 h and almost 100 % after 20 h. The falling-film photocatalytic reactor was operated under irradiation with sunlight and a rapid degradation of microcystin-LR was observed at an illumination intensity of 60,000-110,000 lx; a degradation of 88 % after 5.5 h. Thirdly, two kinds of activated carbons are tested to remove microcystins by adsorption. In the case of wood-base granular activated carbon, repetitive treatment in a continuous-flow mode removed 99% of microcystin-LR at an initial concentration of 2300 ppt in 50 min. In a batch-recirculation mode, on the other hand, it took about 150 min to achieve the same removal. In the case of bamboo-base activated carbon, only 17.7 % of microcystin-LR was removed even at a very low linear velocity of 0.026 m min^-1. Finally, a combined process of the photocatalytic degradation and adsorption by activated carbon is discussed.

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Physico-chemical and biological approaches were studied on the mixed-industrial effluent running through the closed drainage system (CDS) within an industrial zone and the study was run separately. The mixed-industrial effluent comprised effluents from various industries that have been treated at their own treatment plant system and should have met the regulated limits before discharging into the CDS. But in this case it happened adversely. The aim of this study was to compare the ability of both approaches in treating the mixed-effluent based on the COD removal. The biological study was carried out at 0.5 mg/L dissolved oxygen (DO) concentrations in bench scale activated sludge with the addition of granular activated carbon (GAC), at 4 hours hydraulic retention time (HRT). Inorganic coagulant; Alum and poly-aluminum chloride (PACl) each in combination with three different types of powder activated carbon (PAC) used in the physico-chemical treatment. The experiments were operated at inherent pH of the mixed-industrial effluent. The results for physico-chemical treatment shows that if the pH of the mixed-industrial effluent remains unaltered, a higher dosage of both alum and polyaluminium chloride (PACl) are needed to reduce COD value by 17.5% and 30.2% for PAC type A, 31.5% and 67.4% for PAC type B, 36.1% and 43.6% for PAC type C respectively. The results obtained under suspended-fixed growth system illustrate about 72% of the COD been removed.

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UV-irradiated titanium oxide can degrade various kinds of organic compounds by hydroxyl radicals (HO·) that are produced during the reaction. We recently found that in this reaction, H₂O₂ is formed at a concentration level of ppm (parts per million) from water and the initial rate of formation of H₂O₂ is proportional to the initial rates of degradation of HCOOH and HCHO. On the other hand, Fenton reaction also utilizes HO· to degrade organic compounds. In this reaction, however, H₂O₂ must be added to a reaction mixture to produce HO·. To overcome this disadvantage, this work investigates a new process consisting of the photocatalytic reaction on UV-irradiated titanium oxide and the Fenton reaction on a Nafion membrane adsorbing ferrous ions, in which the Fenton reaction proceeds by utilizing the H₂O₂ formed in the photocatalytic reaction. The experimental result using HCOOH as a reactant clearly showed that the Fenton reaction occurs without addition of H₂O₂ and adjustment of a pH value and the combined process results in an increase in the rate of degradation of HCOOH. Also, it was confirmed that the Nafion membrane after repeated seven batch runs can quickly be regenerated with L(+)-ascorbic acid and then used repeatedly.

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Toxic organic chemicals, volatile organic compounds, (VOCs) and pesticides, in wastewaters were biologically degraded by utilizing waste activated sludge in a gas-liquid-solid three-phase slurry bioreactor. The biodegradation kinetics of toxic organic chemicals was examined in batch experiments at varying initial toxic organic chemical concentrations, waste activated sludge concentrations and aeration rates. The bioreactor constructed from plexiglass had an internal diameter of 75 mm and a working volume of 2 L. As an activated sludge, waste activated sludge obtained from Kawagoe City Wastewater Treatment Plant located in Saitama, Japan was used. It was found that the biodegradation rates of toxic organic chemicals were approximately described by first order kinetics. However, in the case of the VOC used in this study, o-cresol, the shape of the curves for specific biodegradation rates of was typical for the substrate inhibition kinetics. Therefore, the kinetic parameters of aerobic o-cresol biodegradation were estimated using Haldane's substrate inhibition equation. The oxygen consumption during the biodegradation process was also examined. The oxygen consumption rate was adequately described by the Haldane type model. The biodegradation of toxic organic chemicals by waste activated sludge and the change of dissolved oxygen concentration in the slurry bioreactor were successfully simulated.

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The engineering and technology of the activated sludge system are well established and have been applied worldwide for the biological removal of organic compounds from wastewater. In our recent study, we used activated sludge system for treatment of wastewater from cassava starch. The effects of process variable such as aeration time, and airflow rate on the BOD removal and dissolved oxygen were studied. From the experimental results, it was found that residence time and air flow rate give significant effect on the BOD removal and dissolved oxygen content. The maximum removal can be achieved by the activated sludge plug flow system in our laboratory was 90 % (from 6000 mg/L BOD to 600 mg/L) and the dissolved oxygen content in effluent increased until 4.2 - 4.7 mg/L.

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Recently, harmful ion, nitrate nitrogen, is contained so much in wastewater such as an agricultural effluent. If this ion flows into a river etc., it causes a serious social problem such as water pollution and a bad influence to an ecological system. Therefore, development of the effective technology for removing nitrate ion is desired. Generally, the removal of nitrates ion is based on the reduction by hydrogen donor reagent, but it is difficult to control the degree of reduction because of its complicated reaction mechanism. The reactions of nitric compounds are governed by standard oxidation-reduction potentials of each species. The reduction of nitrates ion favorably proceeds under low pH, on the contrary, the formation of nitrogen gas is desired to keep the reaction condition at high pH. In this paper, we proposed a new method to convert nitrates ion into nitrogen gas via nitrous acid and ammonium ions. 10 ppm of nitrates ion and several organic acids were reacted at 200 to 350 °C under 18 MPa to examine an optimum condition to reduce the nitrates ion. It was found that nitrates ion was converted completely into the equivalent mixture of nitrous acid and ammonium ions using 1000ppm of citrate acid as an additive. Thus converted mixture was reacted for 70 s under 7 of pH at 340°C in 18MPa of pressure, and these ions were successfully converted into nitrogen. Thus, it was found that the proposed method is effective for removing nitrates ion at short contact time.

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Plug flow pattern is normally assumed in order to simplify the biofilter models. This assumption could result in the discrepancies between the predicted and experimental results since the axial dispersion in the gas phase could easily occur. Therefore, a steady state model taking into account dispersion effects was developed in this study. The model predictions were compared to experimental data from a downward flow biofilter using compost for removing methanol. The dispersion coefficient used in the model was determined by curve fitting with a set of experiment and was found to be a function of methanol concentration. Comparing to the plug flow model, the predicted results of dispersion model appear to fit well with the experimental data.Water movement within the bed was also predicted. The leachate from the biofilter was collected and compared to the model predictions. The amount of collected water increased much more rapidly with inlet methanol concentration than predicted by the model. In practice, water is continuously removed from the bed by convection, resulting in the bed drying. Therefore, the steady state model is no longer valid unless the optimum amount of water is added to the bed to keep the solid phase in equilibrium. However, this model can be used to optimize the amount of additional water to ensure the maximum microbial activity during operation.

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API separator sludge is usually present in wastewater treatment plants of refinery and must be treated properly. The recovery of light components from the sludge containing water, oil and solid was investigated by means of chemical treatment. Surfactant and electrolyte were used to recover the oil from the solid surface and destabilize the oil droplets, respectively. Ferric salt was used as a coagulant to reduce the electrostatic repulsion of the oil droplets. Polyelectrolytes were used to flocculate these oil droplets in the system. The effect of several parameters on the recovery was observed, namely, (1) the type and concentration of surfactant, (2) the concentration of electrolyte, (3) the concentration of both coagulant and flocculant, (4) pH of the solution and (5) the presence of the nonionic surfactant Empilan KB-7. It was found that the surfactant and electrolyte system requires very high concentration of surfactant and electrolyte which results in the economic and corrosion problems. On the other hand, the use of polyelectrolyte together with flotation technique is preferable for chemical treatment because the maximum recovery, 90-99.7%, could be achieved with a small amount of polyelectrolyte. The optimum dosages are approximately 5-20 mg/l of polyacrylamide.

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A novel method using the mesophilic anaerobic bacterium Shewanella algae was proposed to recover gold dissolved in aqueous solutions. The anaerobic bacterium was capable of precipitating gold particles by reducing Au(III) ions in aqueous HAuCl₄ solutions with molecular hydrogen as the electron donor. In the presence of S. algae cells and hydrogen gas, the Au(III) ions in the solutions were almost completely reduced and precipitated from 1 mol/m³ aqueous HAuCl₄ solution within 60 min at room temperature. The formation of gold nanoparticles was also evidenced by the color change of the suspension (the surface plasmon absorption of gold nanoparticles). The TEM observations revealed that the microbially induced gold nanoparticles adheres to the bacterial cells. These results demonstrate that the gold-reducing bacterium S. algae has the very attractive ability to recover gold from aqueous solutions without using excess energies and chemicals in order to prevent further environmental contamination.

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Phytoremediation, a new plant-based technology for the removal of toxic contaminants from soil and water, is a potentially attractive approach. Though a number of plants have been identified as hyperaccumulators for the phytoextraction of a variety of metals and some has been used in field applications, no study on recovery and recycle of heavy metals from contaminated soil has been investigated. Recently, Athyrium yokoscense has been discovered as an efficacious heavy metallic hyperaccumulating fern plant. In this work, the purification of contaminated soil with heavy metals using A. yokoscense and the development of system for recovering valuable metals by steam explosion and Wayman's extraction were investigated. After the harvest of A. yokoscense adsorbed heavy metals from contaminated soil, it was treated by steam explosion and separated into extractive components, i.e. holocellulose, water-soluble material, Klason lignin, and methanol-soluble lignin, using Wayman's extraction method. The distribution of metals in the components was clarified using ICP emission spectrometry.

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A polyol-ligand-containing porous hollow-fiber membrane for the recovery of antimony (III) was prepared by radiation-induced graft polymerization of an epoxy-group-containing vinyl monomer, glycidyl methacrylate (GMA), and by subsequent functionalization with N-methylglucamine (NMG) and 3-amino-1,2-propanediol (APD), that form a coordination complex with Sb (III). The structure of NMG-Sb(III) and APD-Sb(III) complexes in aqueous solution were determined by electron ionization-time-of-flight mass spectrometer (ESI-TOF-MS), and the binding ratio of NMG or APD to Sb (III) is 2 : 1. An antimony(III) oxide solution (10 mg-Sb/L, pH 11.4) was forced to permeate through the submicron-diameter pores of the polyol-ligand-containing porous hollow-fiber membranes. The equilibrium binding capacity for antimony(III) to the NMG-ligand-containing porous hollow-fiber membrane, 96 g-Sb/kg, was 10 times higher than that of the APD membrane. In a further study of the NMG membrane, the equilibrium binding ratios for antimony(III) to NMG groups were all approximately 0.5, illustrating that the NMG-Sb(III) complex on the fibers was in the ratio of 2 : 1. The results of computational structural analysis of the NMG-Sb(III) complex were in agreement with the experimental results of binding ratio. It was verified that an antimony(III) ion formed a coordination complex with two adjacent hydroxyl groups of two NMG moieties. The length of a functional group and the distance between functional groups on the polymer brush were significant factors to bind antimony(III) through the computational simulation.

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