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Yokohama-shi, Japan

Kitami H.,Japan Central Research Institute of Electric Power Industry | Kitami H.,Japan Certification Services Inc. | Ishihara Y.,Tokai University | Takano J.,Tokai University
Bunseki Kagaku | Year: 2011

Determination of cyanide, fluoride, and phenol in industrial wastewater by continuous flow analysis (CFA) after continuous flow sample distillation has been studied. This analytical method provides high linearity of the calibration curve as well as both repeatability and reproducibility. The correlation coefficients of the calibration curve were estimated to be from 0.9950 to 0.9989 for cyanide, fluoride, and phenol in the concentration range from 0.1 mg L-1 to 1.0 mg L-1. The detection limits calculated on 3 σ at 0.5 mg L-1 were 0.012 mg L-1 for cyanide, 0.014 mg L-1 for fluoride, and 0.008 mg L-1 for phenol. The determination limits calculated on 10 σ at 0.5 mg L-1 were 0.041 mg L-1 for cyanide, 0.045 mg L-1 for fluoride, and 0.028 mg L-1 for phenol. The good results were obtained in recovery tests by using industrial wastewater. This analytical method could be successfully applied to the determination of cyanide, fluoride, and phenol in industrial wastewater. © 2011 The Japan Society for Analytical Chemistry.


Kitami H.Hideaki,Japan Certification Services Inc. | Ishihara Y.,Tokai University | Takano J.,Tokai University
Bunseki Kagaku | Year: 2011

A determination method of 4 kinds of tocopherols in soybean oil by high-performance liquid chromatography (HPLC) with ultraviolet detector (UV) on a triacontyl (C30) silica-gel column has been developed. This analytical method provides high linearity of the calibration curve as well as both repeatability and reproducibility. The correlation coefficient of the working curve of calibration were estimated to be from 0.9981 to 0.9998 for 4 kinds of tocopherols in the concentration range from 10 mg L-1 to 100 mg L-1. The limits of detection (LOD) calculated on 3 σ at 10 mg L-1 were 2.0 mg L-1 for α-tocopherol, 2.3 mg L-1 for β-tocopherol, 1.0 mg L-1 for γ-tocopherol, and 0.9 mg L-1 for δ-tocopherol. The limits of quantification (LOQ) calculated on 10 σ at 10 mg L-1 were 6.6 mg L-1 for α-tocopherol, 7.6 mg L-1 for β-tocopherol, 3.3 mg L-1 for γ-tocopherol, and 3.0 mg L-1 for δ-tocopherol. Good results were obtained in recovery tests by using soybean oil. This proposed method could be successfully applied to the determination of 4 kinds of tocopherols in soybean oil. © 2011 The Japan Society for Analytical Chemistry.


Kitami H.,Japan Certification Services Inc. | Kitami H.,Restek Corporation | Ishihara Y.,Tokai University | Takano J.,Tokai University
Bunseki Kagaku | Year: 2013

Eight kinds of catechins are well known because of their antioxidant activity and chemopreventive effects against cancers. The determination of eight kinds of catechins {GC: (-)-gallocatechin; EGC: (-)-epigallocatechin; C: (+)-catechin; EC: (-)-epicatechin; EGCg: (-)-epigallocatechin gallate; GCg: (-)-gallocatechin gallate; ECg: (-)-epicatechin gallate; CG: (-)-catechin gallate} in bottled green tea drinks by high-performance liquid chromatography (HPLC) with an ultraviolet detector (UV) on a cholesteryl group stationary phase column has been developed. This analytical method provides high linearity of the calibration curve as well as both repeatability and reproducibility. The correlation coefficient of the working curve of calibration were estimated to be from 0.9998 to 0.9987 for eight kinds of catechins in the concentration range from 5 mg LT1 to 150 mg L_1. The limits of detection (LOD) calculated on 3(7 at 10 mg LT1 were 0.39 mg LT1 for GC, 0.74 mg LT1 for EGC, 0.07 mg LT1 for C, 0.33 mg LT1 for EC, 0.28 mg LT1 for EGCg, 0.35 mg LT1 for GCg, 0.18 mg LT1 for ECg, and 0.19 mg LT1 for CG. The limits of quantification (LOQ) calculated on 10(7 at 10 mg LT1 were 1.29 mg LT1 for GC, 2.48 mg LT1 for EGC, 0.24 mg LT1 for C, 1.09 mg LT1 for EC, 0.94 mg LT1 for EGCg, 1.17 mg LT1 for GCg, 0.62 mg LT1 for ECg, and 0.65 mg LT1 for CG. Good results (the recoveries were 85.5-109.6% and the relative standard deviations were 2.5-4.9%) were obtained in recovery tests by using bottled green tea drinks. This proposed method could be successfully applied to the determination of eight kinds of catechins in bottled green tea drinks. © 2013 The Japan Society for Analytical Chemistry.


Koizumi K.,Shizuoka Prefectural Research Institute of Fishery | Nakashita R.,Japan Certification Services Inc. | Nakashita R.,Japan Forestry and Forest Products Research Institute | Suzuki Y.,Japan Certification Services Inc. | Suzuki Y.,Japan National Food Research Institute
Nippon Shokuhin Kagaku Kogaku Kaishi | Year: 2011

We examined the use of stable carbon and nitrogen isotope ratios as a potential tool for verifying the geographical origin of Shirasuboshi. Products from 9 primary Shirasuboshi-producing areas in Japan and those imported from China and Korea were examined. The 9 primary production areas in Japan were classified into three groups by cluster analysis of stable carbon and nitrogen isotope ratios. Furthermore, Shirasuboshi imported from China was characterized by higher carbon and lower nitrogen isotope ratios than those from Japan and Korea. These results suggest that stable carbon and nitrogen isotope ratios are useful as tools for determining the geographical origin of Shirasuboshi.


Kitami H.,Japan Central Research Institute of Electric Power Industry | Kitami H.,Japan Certification Services Inc.
Bunseki Kagaku | Year: 2011

This paper describes a simple analytical method for the simultaneous determination of 3 kinds of pesticides for golf courses by high-performance liquid chromatography (UV) with ultraviolet detection (UV) after solid-phase extraction (SPE). This method provides high linearity of the working curve for calibration as well as repeatability and reproducibility. The correlation coefficient of the working curve for calibration were estimated to be from 0.9991 to 0.9998 for the 3 kinds of pesticides for golf courses in the concentration range from 0.5 mg L-1 to 5.0 mg L-1. The limits of detection (LOD) calculated on 3 σ at 0.5 mg L-1 were 0.10 mg L-1 for oxine copper, 0.14 mg L-1 for thiamethoxam, and 0.11 mg L-1 for clothianidin. The limits of quantification (LOQ) calculated on 10 σ at 0.5 mg L-1 were 0.34 mg L-1 for oxine copper, 0.48 mg L-1 for thiamethoxam, and 0.36 mg L-1 for clothianidin. Solid-phase extraction using the stylene-methacrylate copolymer (MA-SDVB) and elution with acetonitrile was recommended for enriching the 3 kind of pesticides. The recoveries from 500 mL of spiked river-water samples at a concentration level of 0.005 mg L-1, concentrated 500 times, were 91.295.6 %, and the relative standard deviations were 3.8~.6% This method could be successfully applied to the determination of 3 kinds of pesticides for golf courses in river-water samples. © 2011 The Japan Society for Analytical Chemistry.

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