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An effective evaluation method for understanding fermentation is required to support the implementation of newly developed yeast strains in brewing. Our group developed a multi-functional separation mode-ion chromatography (MFS-IC) with conductivity and refractive index detectors to separate key species (glucose, ethanol, and organic acids: pyruvate, citrate, L-malate, and succinate) with ethyl α-D-glucoside and glycerol to understand the fermentation behavior in brewing. Optimal chromatographic resolutions for determining eight different key species in rice wine by the MFS-IC were obtained in 45 min on low-molecular size-exclusion chromatographic separation columns modified with a strong cation-exchanger as the stationary phase with an eluent of L-pyroglutamic acid. Understanding the behavior of analytes in rice wine samples during rice wine fermentation enables the monitoring of the progress of saccharification, glycolysis, ethanol fermentation, and the tricarboxylic acid (TCA) cycle. These results are expected to contribute to understanding fermentation characteristics and implementing newly developed yeast strains in the fermentation field. [ABSTRACT FROM AUTHOR]

The color of emeralds is predominantly influenced by the concentration of Cr3+. However, the evaluation of the trend of green color depth of emeralds, based on the practical single crystal synthesis with several instrumental analysis is not investigated in previous researches. Specifically, if the Cr2O3 content is controlled to be in the range of 0.2–0.4 wt%, then emeralds can be synthesized with the most esthetically pleasing color. Therefore, the effect of Cr2O3 concentration within the aforementioned range on the color of emeralds is studied using powder X‐ray diffractometry, digital microscopy, electron probe microanalysis, and micro‐spectrophotometry to understand how to achieve the most esthetically pleasing color. As a result, detailed behaviors relating to the absorbances, L*, a*, and b* values, and the relationship between the emerald crystal color changes and increases in Cr2O3 concentration are elucidated. Notably, the absorbance, L* and a* values change significantly when the Cr2O3 concentration is low (0.00–0.236 wt%). However, the changes in these values are moderate when the Cr2O3 concentration is higher (0.236–0.504 wt%). [ABSTRACT FROM AUTHOR]

An effective method for monitoring the progress of rice wine fermentation (saccharification, glycolysis system, ethanol fermentation, and the TCA cycle) is required owing to the decreasing human resources in rice wine brewing and dramatically increasing export quantity of rice wine. This study aimed to develop an anion-exclusion/size-exclusion/reversed-phase chromatographic (AEC/SEC/RPC) separation protocol for the simultaneous determination of sugars, ethanol, inorganic, and organic acids for the effective monitoring of rice wine fermentation processes. Optimal chromatographic resolutions were obtained by the combination of a polymer-based size-exclusion column and H+-form weakly acidic cation-exchange resin column with a 20.0 mM phthalic acid eluent. The optimized AEC/SEC/RPC separation system determined 16 different species during rice wine fermentation in a single analysis. The developed AEC/SEC/RPC method demonstrated the below useful advantages for (1) evaluating the progress of rice wine fermentation; (2) evaluating the activity of brewing yeast from the behaviors of glucose, phosphate, and ethanol concentration; and (3) obtaining good correlation between the developed and official methods for monitoring glucose and ethanol. Consequently, several beneficial information was obtained for the process control of rice wine brewing by the developed method. [ABSTRACT FROM AUTHOR]

We evaluated the use of ion-exclusion chromatographic systems for analyzing the behavior of inorganic ions (e.g., bicarbonate, sulfate, chloride, nitrate, phosphate, dissolved silicate, sodium, ammonium, potassium, magnesium, and calcium ions) in a suburban river located in Jakarta, Indonesia. Carbonate, phosphate, and silicate ion concentrations were determined using ion-exclusion chromatography (IEC) on a weakly acidic cation-exchange resin column (WCX) in the H+-form with water eluent. Other ions were identified by ion-exclusion/cation-exchange chromatography (IEC/CEC) on a WCX column with tartaric acid eluent. The use of IEC systems for water quality monitoring was advantageous for the following reasons: (1) the concentrations of analyte ions, except NO3 - and silicate ions, increased from upstream to downstream; and (2) the speciation of inorganic nitrogen ions could be analyzed by single injection into the IEC/CEC. The IEC approach provided beneficial information for the construction of sewage treatment facilities in our study area. Results showed that (1) the analyte concentrations for samples obtained in the downstream area were higher than those in the upstream area owing to contamination by domestic sewage; (2) the concentrations of NO3 - and NH4 + correlated with the concentration of dissolved oxygen; and (3) bicarbonate concentrations increased downstream, likely due to respiration of bacteria and dissolution of concrete under low-oxygen conditions. [ABSTRACT FROM AUTHOR]

In this study, ion-exclusion/cation-exchange chromatography (IEC/CEC) using dual-ion-exchange groups (carboxy and sulfo groups) for the simultaneous determination of anions (SO42−, Cl−, NO3−, and HPO42−) and cations (Na+, NH4+, K+, Mg2+, and Ca2+) was developed. By using the combination of dual-ion-exchange groups, simultaneous separation of inorganic ions with HPO42− was achieved that was impossible by the conventional IEC/CEC based on the single-ion-exchange group (carboxy group). This method was applied to the monitoring of inorganic ionic nutrients in fertilizer solution samples in hydroponic culture. As a result, a higher peak resolution of inorganic anions and cations with phosphate ion using IEC/CEC with dual-ion-exchange groups was achieved in the absence of matrix effects. In addition, the developed method helps to understand the behavior of ionic nutrients in fertilizer solution during hydroponic cultivation and is potentially useful for the individual fertilization of ionic nutrients. [ABSTRACT FROM AUTHOR]

Kuantan in Pahang, Malaysia has experienced rapid development and environmental degradation over the past decade following the implementation of The National Physical Plan 2005. To assess water quality and identify polluted areas in the region, we measured the water chemistry and microbial activity in response to land-use changes for four major rivers, namely, Pahang, Kuantan, Belat, and Galing, using data from ion chromatography and portable water quality monitoring devices. The following were concluded: (1) significant differences in chemical oxygen demand, COD concentration among all monitored rivers suggest that COD and its associated biological reactions are key parameters to assess anthropogenic water quality degradation in our study area; (2) due to the low anthropogenic wastewater pollution, the dominant microbial reactions in the Pahang, Kuantan, and Belat rivers were aerobic microbial oxidation of organic compounds and nitrification by nitrifying bacteria, allowing the rivers to self-purify; (3) the Galing River predominantly experiences anaerobic decomposition of organic compounds through microbial denitrification and sulfate reduction due to the heavy anthropogenic land use in the river basin; and (4) the western side of the Galing River and upstream sites located within the industrial and business/servicing areas in the Kuantan city center experience the heaviest pollution. [ABSTRACT FROM AUTHOR]