Soluble expression of halophilic starch-binding domain （SBD1） from Kocuria α-amylase was low due to its instability in recombinant host Escherichia coli cells. Here, the stable SBD1 protein was expressed efficiently with an aggregation-prone peptide tag in insoluble E. coli inclusion bodies （IBs）. Insoluble SBD1 protein with the tag, thus obtained, was easily solubilized with 8 M urea and refolded into an active form by simple urea dilution. The yield of active SBD1 with the tag after the solubilization / dilution method was 15 ～ 30 times higher than that of direct expression of SBD1 in soluble fraction.

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The Piran region is famous for salt production in Slovenia. The salt produced in Piran is familiar for its good quality and taste. In the Piran saltern, the bottom of the crystallization ponds used in the salt production process is covered with a microbial mat （called “Petola”） and tends to be cultivated in order to prevent the mixing of mud underneath with precipitated crystals of salt （halite）. Petola's microbiological ecology has been studied. However, although Piran salt is known to have a unique umami taste, the relationship between microbes and umami taste remains unknown. Therefore, the purpose of this study is to measure glutamic acid, a source of the umami taste, in various salt products and to investigate the microbial community in salt products. Results showed that glutamic acid was detected in eight of the 35 products measured in this study and all the salt products in which glutamic acid was detected were made in solar salterns. Moreover, this study revealed that Piran salts contain higher concentrations of glutamic acid, one source of the umami taste, than the other salt products. Besides, bacterial diversity in salt products was also relatively high in Piran traditional salt, suggesting that halophilic microorganisms may be produced by complex interactions with dissolved organic matter in seawater or salterns to generate the umami taste.

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We applied transient isotachophoresis （tITP） and capillary zone electrophoresis （CZE） with indirect UV detection to determine F⁻ in salts. The limit of detection （LOD, signal to noise ratio （S/N）＝3）） and limit of quantification （LOQ, S/N＝10） for F⁻ respectively reached 0.007 and 0.023 mg/L using a capillary with larger inner diameter （100 μm）. The respective values of the relative standard deviation （RSD, n＝4） of the migration time, peak area, and peak height for F⁻ were 0.35, 2.7, and 2.7 ％. Effects of coexisting components such as aluminum （Al³⁺）, iron （Fe³⁺）, magnesium （Mg²⁺）, and calcium （Ca²⁺） were examined. The adverse effects were resolved using metal complexation with diethylenetriamine pentaacetic acid （DTPA）. The proposed method was used to find F⁻ in salt samples. Results for CZE agreed with those obtained using conventional spectrophotometry.

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Studying the settlement behavior of cypris larvae is closely related to the economical operation of ships while reducing CO₂ emissions into the atmosphere. The areas showing the existence of relatively higher values of the probability density function were visualized by using the values of the probability density function obtained from doing a kernel density estimation. The areas estimated were located non-uniformly on the flat plate. In particular, it was estimated clearly at the lower west side on Surface II. Cypris larvae seem to prefer to settle not in the central area but near the surrounding areas under intense competition.

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Palladium, a platinum-group metal, is used in various industrial sectors, and its demand has increased in recent years. Here, we describe the palladium biosorption capacity of Enterobacter oligotrophicus CCA6^T. After E. oligotrophicus CCA6^T was cultured, the washed cells were used in a biosorption test, and their capacity was confirmed by transmission electron microscopy （TEM） analysis. Based on the TEM images, the cells of E. oligotrophicus CCA6^T were not decomposed by adding palladium, and E. oligotrophicus CCA6^T had palladium biosorption capacity.

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Cation-exchange membranes with improved electrodialysis and mechanical strength for manufacturing edible salt were prepared by electron-beam-induced graft polymerization. First, styrene （St） and chloromethyl styrene （CMS） were co-grafted onto an EB-irradiated ultra-high molecular weight polyethylene film. Second, through a reaction with chlorosulfonic acid, a sulfonic acid group was introduced while incorporating the crosslinked structure into the cograft chains. The cation-exchange membranes that were prepared with various CMS contents in a vinyl monomer solution were stored in 0.5 mol/L NaCl at 25 ° C to evaluate the time course of the water content, membrane resistance, and tensile strength. Over a 150-day storage period, the water content increased and the membrane resistance and tensile strength decreased. This tendency can be explained by the fact that the cograft chains are crosslinked to depress water inclusion in the sulfonic acid group containing a polymer network. The CMS content in the vinyl monomer solution governed the degree of crosslinking of the polymer network of the membrane, affecting the performance of the electrodialysis. The cation-exchange membrane, prepared at a CMS content of 17 % and a degree of cografting of 74 %, exhibited 20 % higher chloride ion concentration of brine for the electrodialysis compared with a commercially available cation-exchange membrane.

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A reverse electrodialysis （RED） system is emerging as a technology that can harvest electric power from salinity gradient energy （SGE） using ion exchange membranes （IEMs）. In many studies, seawater and river water have been used as the feed solutions of RED. On the other hand, to generate high amounts of electric energy, industrial salty wastewater （ISW） could be feed solutions because of its high salinity. In this study, to consider the use of ISW for RED, RED performance of a lab-scale RED which were fed 3 types of ISW pairs, were investigated. As the best performance in this research, the RED stack fed with solutions of ISW having ca. 190 and 7.6 mS/cm of conductivity showed 2.3 W/m² of power density when using low membrane resistance IEM pairs.

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This study determines a method for the synthesis of carbonates from removed-K bitterns using ultrasonic cavitation. The results suggest that dolomite （CaMg（CO₃）₂） nanoparticles can be easily synthesized by irradiating ultrasonic waves for 20 min using a removed-K bittern adjusted to a Ca/Mg molar ratio of 0.5. In addition, the immersion method was used to convert dolomite, which emits green or red light, into a phosphor. By changing the mixing ratio of the green- and red-emitting phosphor, it was possible to produce dolomite phosphors with control over emission colors such as green, yellow-green, yellow, orange, and red. These phosphors can be applied as guide lights and interior lights.

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In this study, cation exchange membranes （CEMs） were prepared using sulfonated polyether sulfone （SPES）, and the characteristics of the membrane were then evaluated. Donnan dialysis experiments with the CEM were performed using NaCl as the driving solution of uphill transport of Ca^2＋ ions. The prepared CEM had almost the same ionic transport properties as that of a commercial CEM. The Donnan dialysis showed that the Ca^2＋ ion concentration on the feed solution side decreased while Na^＋ ions concentration increased, indicating that Donnan dialysis has a potential application for separation processes such as water softening.

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The forward osmosis （FO） process uses a spontaneous water permeation phenomenon driven by an osmotic pressure difference between a feed solution （FS） and a draw solution （DS） through a semipermeable membrane. Hence, it is assumed that seawater desalination and feed solution concentration using FO processes can be conducted at low energy and cost. It is crucial to develop an optimal DS for the FO process before it can be put into practical use. The DS must have the following characteristics: （1） Develops higher osmotic pressure than FS, （2） Easy to regenerate and recover, （3） Low leakage, and （4） Low viscosity. Particularly, we propose low-grade waste heat to reduce energy consumption during DS regeneration and chose a temperature phase transition type DS that separates into water and solute components based on thermal response. In this study, we synthesized six alkyl imidazolium type ionic liquids （ILs） having perchlorate anion （［ClO₄］）, phase transition characteristics, and osmotic pressure, and the consequent FO performance was examined. The synthesized ILs, 1-ethyl-3-propylimidazolium perchlorate ［Im （2.0.3）］［ClO₄］ and 1,2-dimethyl-3-propylimidazolium perchlorate ［Im （1.1.3）］［ClO₄］, showed an upper critical solution temperature type phase transition in the temperature range of 25 ℃ to 50 ℃. The FO test confirms that pure water can be derived from saltwater using the osmotic pressure of DS. In comparison to other synthesized ILs, ［Im （1.1.3）］［ClO₄］ showed higher performance in phase diagrams and osmotic pressure.

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In this study, PVA-based profiled IEMs were prepared by mixing an ethylene-vinyl alcohol copolymer （EVOH） and PVA-based polyions, and then their basic properties and RED power generation performance were evaluated. By blending EVOH with a PVA-based block copolymer, we obtained flat-shaped cation and anion exchange membranes （F-CEM and F-AEM） that improve the mechanical strength of IEMs with a high transport number and low membrane resistance. The profiled CEMs （PF-CEMs） were prepared by hot-pressing F-CEMs. The stack using PF-CEMs/F-AEMs showed the maximum power output of 2.07 mW at 7.0 mA of current.

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In this study, we evaluated the power generation performance of a small stack with commercial ion exchange membranes in the case of using high salt solutions with the same conductivity as brine from seawater RO desalination plants, with the aim of investigating the effect of the basic properties of IEMs on power generation performance of RED stacks. FKS-20/FAS-20 showed the highest power density of 3.12 W/m² because the membrane resistance of FKS-20/FAS-20 was lowest in all the IEMs. This indicates that the effect of the difference in the osmotic water coefficient and permselectivity in all the IEMs on the performance will be small compared to that in the membrane resistance even when using high salinity solutions as the high concentration solution of RED stack.

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