The Experts below are selected from a list of 324 Experts worldwide ranked by ideXlab platform

Yoshihisa Nakano - One of the best experts on this subject based on the ideXlab platform.

  • Comparison of a Microbiological Assay and a Fully Automated Chemiluminescent System for the Determination of Vitamin B12 in Food
    Journal of Agricultural and Food Chemistry, 1998
    Co-Authors: Fumio Watanabe, Yoshiyuki Tamura, Shigeo Takenaka, Yoshihisa Nakano
    Abstract:

    A fully automated Chemiluminescence Analyzer for the determination of vitamin B12 in serum has been commercialized and clinically used. To determine the applicability of this apparatus in food analysis, vitamin B12 was assayed in foods by the chemiluminescent method, which was compared with a microbiological method. In shellfishes and spirulina, the values determined by the microbiological method were ∼6−8-fold greater than the values determined by the Chemiluminescence method, although there was good similarity between the values by the two methods in other foods. Except for the shellfishes and spirulina, which contained substantial amounts of vitamin B12-substitutive compounds or inactive vitamin B12 analogues (or both), the observed correlation coefficient between the methods in the foods tested was excellent (r = 0.99, y = 1.2x − 1.1, n = 9). The Chemiluminescence method was suitable for the determination of vitamin B12 in foods as well as in serum and was simpler (fully automated) and more rapid (180...

  • Comparison of a microbiological assay and a fully automated chemiluminescent system for the determination of vitamin B12 in food
    Journal of Agricultural and Food Chemistry, 1998
    Co-Authors: Fumio Watanabe, Katsuo Abe, Yoshiyuki Tamura, Shigeo Takenaka, Yoshihisa Nakano
    Abstract:

    A fully automated Chemiluminescence Analyzer for the determination of vitamin B12 in serum has been commercialized and clinically used. To determine the applicability of this apparatus in food analysis, vitamin B12 was assayed in foods by the chemiluminescent method, which was compared with a microbiological method. In shellfishes and spirulina, the values determined by the microbiological method were ?6?8-fold greater than the values determined by the Chemiluminescence method, although there was good similarity between the values by the two methods in other foods. Except for the shellfishes and spirulina, which contained substantial amounts of vitamin B12-substitutive compounds or inactive vitamin B12 analogues (or both), the observed correlation coefficient between the methods in the foods tested was excellent (r = 0.99, y = 1.2x ? 1.1, n = 9). The Chemiluminescence method was suitable for the determination of vitamin B12 in foods as well as in serum and was simpler (fully automated) and more rapid (180 samples analyzed per hour), highly selective (use of intrinsic factor, the most specific vitamin B12-binding protein), and reproducible (coefficients of variation of 1.2?6.7%) than the microbiological method. Keywords: Vitamin B12; bioassay; Chemiluminescence; intrinsic factor; food A fully automated Chemiluminescence Analyzer for the determination of vitamin B12 in serum has been commercialized and clinically used. To determine the applicability of this apparatus in food analysis, vitamin B12 was assayed in foods by the chemiluminescent method, which was compared with a microbiological method. In shellfishes and spirulina, the values determined by the microbiological method were ?6?8-fold greater than the values determined by the Chemiluminescence method, although there was good similarity between the values by the two methods in other foods. Except for the shellfishes and spirulina, which contained substantial amounts of vitamin B12-substitutive compounds or inactive vitamin B12 analogues (or both), the observed correlation coefficient between the methods in the foods tested was excellent (r = 0.99, y = 1.2x ? 1.1, n = 9). The Chemiluminescence method was suitable for the determination of vitamin B12 in foods as well as in serum and was simpler (fully automated) and more rapid (180 samples analyzed per hour), highly selective (use of intrinsic factor, the most specific vitamin B12-binding protein), and reproducible (coefficients of variation of 1.2?6.7%) than the microbiological method. Keywords: Vitamin B12; bioassay; Chemiluminescence; intrinsic factor; food

Fumio Watanabe - One of the best experts on this subject based on the ideXlab platform.

  • Comparison of a Microbiological Assay and a Fully Automated Chemiluminescent System for the Determination of Vitamin B12 in Food
    Journal of Agricultural and Food Chemistry, 1998
    Co-Authors: Fumio Watanabe, Yoshiyuki Tamura, Shigeo Takenaka, Yoshihisa Nakano
    Abstract:

    A fully automated Chemiluminescence Analyzer for the determination of vitamin B12 in serum has been commercialized and clinically used. To determine the applicability of this apparatus in food analysis, vitamin B12 was assayed in foods by the chemiluminescent method, which was compared with a microbiological method. In shellfishes and spirulina, the values determined by the microbiological method were ∼6−8-fold greater than the values determined by the Chemiluminescence method, although there was good similarity between the values by the two methods in other foods. Except for the shellfishes and spirulina, which contained substantial amounts of vitamin B12-substitutive compounds or inactive vitamin B12 analogues (or both), the observed correlation coefficient between the methods in the foods tested was excellent (r = 0.99, y = 1.2x − 1.1, n = 9). The Chemiluminescence method was suitable for the determination of vitamin B12 in foods as well as in serum and was simpler (fully automated) and more rapid (180...

  • Comparison of a microbiological assay and a fully automated chemiluminescent system for the determination of vitamin B12 in food
    Journal of Agricultural and Food Chemistry, 1998
    Co-Authors: Fumio Watanabe, Katsuo Abe, Yoshiyuki Tamura, Shigeo Takenaka, Yoshihisa Nakano
    Abstract:

    A fully automated Chemiluminescence Analyzer for the determination of vitamin B12 in serum has been commercialized and clinically used. To determine the applicability of this apparatus in food analysis, vitamin B12 was assayed in foods by the chemiluminescent method, which was compared with a microbiological method. In shellfishes and spirulina, the values determined by the microbiological method were ?6?8-fold greater than the values determined by the Chemiluminescence method, although there was good similarity between the values by the two methods in other foods. Except for the shellfishes and spirulina, which contained substantial amounts of vitamin B12-substitutive compounds or inactive vitamin B12 analogues (or both), the observed correlation coefficient between the methods in the foods tested was excellent (r = 0.99, y = 1.2x ? 1.1, n = 9). The Chemiluminescence method was suitable for the determination of vitamin B12 in foods as well as in serum and was simpler (fully automated) and more rapid (180 samples analyzed per hour), highly selective (use of intrinsic factor, the most specific vitamin B12-binding protein), and reproducible (coefficients of variation of 1.2?6.7%) than the microbiological method. Keywords: Vitamin B12; bioassay; Chemiluminescence; intrinsic factor; food A fully automated Chemiluminescence Analyzer for the determination of vitamin B12 in serum has been commercialized and clinically used. To determine the applicability of this apparatus in food analysis, vitamin B12 was assayed in foods by the chemiluminescent method, which was compared with a microbiological method. In shellfishes and spirulina, the values determined by the microbiological method were ?6?8-fold greater than the values determined by the Chemiluminescence method, although there was good similarity between the values by the two methods in other foods. Except for the shellfishes and spirulina, which contained substantial amounts of vitamin B12-substitutive compounds or inactive vitamin B12 analogues (or both), the observed correlation coefficient between the methods in the foods tested was excellent (r = 0.99, y = 1.2x ? 1.1, n = 9). The Chemiluminescence method was suitable for the determination of vitamin B12 in foods as well as in serum and was simpler (fully automated) and more rapid (180 samples analyzed per hour), highly selective (use of intrinsic factor, the most specific vitamin B12-binding protein), and reproducible (coefficients of variation of 1.2?6.7%) than the microbiological method. Keywords: Vitamin B12; bioassay; Chemiluminescence; intrinsic factor; food

Nicolas Brüggemann - One of the best experts on this subject based on the ideXlab platform.

  • N_2O and NO_x emissions by reactions of nitrite with soil organic matter of a Norway spruce forest
    Biogeochemistry, 2017
    Co-Authors: Wulf Amelung, Eva Lehndorff, Michael Schloter, Harry Vereecken, Nicolas Brüggemann
    Abstract:

    Nitrite (NO_2 ^−) as an important intermediate of the biological nitrogen cycle is particularly reactive in acidic soils and acts as a source of N_2O and NO_x (NO and NO_2). However, abiotic and biotic pathways of NO_2 ^−-driven N_2O and NO_x production in forest soil and the role of soil organic matter (SOM) in these processes are still unclear. In this study, NO_2 ^− was applied to both unsterile and sterilized soil samples as well as to different SOM fractions from a Norway spruce forest. Biotic and abiotic N_2O emission was measured with an infrared absorption Analyzer and gas chromatography, while NO_x emission was quantified with a Chemiluminescence Analyzer. Isotopic signatures of N_2O (δ^15N^bulk, δ^18O, and ^15N-N_2O site preference) were analyzed with an isotope ratio mass spectrometer. After NO_2 ^− addition, a large amount of NO_x was emitted immediately, while N_2O emission occurred 15–60 min later and was much lower compared to NO_x. Sterilization of soil decreased N_2O emission significantly, but not NO_x emission. The ^15N site preference of N_2O ranged from 7.98 to 11.58‰ for abiotic and 4.69–7.42‰ for biotic sources. The fulvic acid fraction contributed the most to abiotic N_2O emission, while the fastest NO and N_2O emission occurred after NO_2 ^−application to the humin fraction, followed by the humic acid fraction. These results are important for the future understanding of NO_x and N_2O sources, as well as the use of isotopic signatures for source-partitioning N_2O emission from soil. Graphical Abstract

Kwang Seok Oh - One of the best experts on this subject based on the ideXlab platform.

  • Chemiluminescence Analyzer of nox as a high throughput screening tool in selective catalytic reduction of no
    Science and Technology of Advanced Materials, 2011
    Co-Authors: Kwang Seok Oh
    Abstract:

    A Chemiluminescence-based Analyzer of NOx gas species has been applied for high-throughput screening of a library of catalytic materials. The applicability of the commercial NOx Analyzer as a rapid screening tool was evaluated using selective catalytic reduction of NO gas. A library of 60 binary alloys composed of Pt and Co, Zr, La, Ce, Fe or W on Al2O3 substrate was tested for the efficiency of NOx removal using a home-built 64-channel parallel and sequential tubular reactor. The NOx concentrations measured by the NOx Analyzer agreed well with the results obtained using micro gas chromatography for a reference catalyst consisting of 1 wt% Pt on γ-Al2O3. Most alloys showed high efficiency at 275 °C, which is typical of Pt-based catalysts for selective catalytic reduction of NO. The screening with NOx Analyzer allowed to select Pt-Ce(X) (X=1–3) and Pt–Fe(2) as the optimal catalysts for NOx removal: 73% NOx conversion was achieved with the Pt–Fe(2) alloy, which was much better than the results for the reference catalyst and the other library alloys. This study demonstrates a sequential high-throughput method of practical evaluation of catalysts for the selective reduction of NO.

Yoshiyuki Tamura - One of the best experts on this subject based on the ideXlab platform.

  • Comparison of a Microbiological Assay and a Fully Automated Chemiluminescent System for the Determination of Vitamin B12 in Food
    Journal of Agricultural and Food Chemistry, 1998
    Co-Authors: Fumio Watanabe, Yoshiyuki Tamura, Shigeo Takenaka, Yoshihisa Nakano
    Abstract:

    A fully automated Chemiluminescence Analyzer for the determination of vitamin B12 in serum has been commercialized and clinically used. To determine the applicability of this apparatus in food analysis, vitamin B12 was assayed in foods by the chemiluminescent method, which was compared with a microbiological method. In shellfishes and spirulina, the values determined by the microbiological method were ∼6−8-fold greater than the values determined by the Chemiluminescence method, although there was good similarity between the values by the two methods in other foods. Except for the shellfishes and spirulina, which contained substantial amounts of vitamin B12-substitutive compounds or inactive vitamin B12 analogues (or both), the observed correlation coefficient between the methods in the foods tested was excellent (r = 0.99, y = 1.2x − 1.1, n = 9). The Chemiluminescence method was suitable for the determination of vitamin B12 in foods as well as in serum and was simpler (fully automated) and more rapid (180...

  • Comparison of a microbiological assay and a fully automated chemiluminescent system for the determination of vitamin B12 in food
    Journal of Agricultural and Food Chemistry, 1998
    Co-Authors: Fumio Watanabe, Katsuo Abe, Yoshiyuki Tamura, Shigeo Takenaka, Yoshihisa Nakano
    Abstract:

    A fully automated Chemiluminescence Analyzer for the determination of vitamin B12 in serum has been commercialized and clinically used. To determine the applicability of this apparatus in food analysis, vitamin B12 was assayed in foods by the chemiluminescent method, which was compared with a microbiological method. In shellfishes and spirulina, the values determined by the microbiological method were ?6?8-fold greater than the values determined by the Chemiluminescence method, although there was good similarity between the values by the two methods in other foods. Except for the shellfishes and spirulina, which contained substantial amounts of vitamin B12-substitutive compounds or inactive vitamin B12 analogues (or both), the observed correlation coefficient between the methods in the foods tested was excellent (r = 0.99, y = 1.2x ? 1.1, n = 9). The Chemiluminescence method was suitable for the determination of vitamin B12 in foods as well as in serum and was simpler (fully automated) and more rapid (180 samples analyzed per hour), highly selective (use of intrinsic factor, the most specific vitamin B12-binding protein), and reproducible (coefficients of variation of 1.2?6.7%) than the microbiological method. Keywords: Vitamin B12; bioassay; Chemiluminescence; intrinsic factor; food A fully automated Chemiluminescence Analyzer for the determination of vitamin B12 in serum has been commercialized and clinically used. To determine the applicability of this apparatus in food analysis, vitamin B12 was assayed in foods by the chemiluminescent method, which was compared with a microbiological method. In shellfishes and spirulina, the values determined by the microbiological method were ?6?8-fold greater than the values determined by the Chemiluminescence method, although there was good similarity between the values by the two methods in other foods. Except for the shellfishes and spirulina, which contained substantial amounts of vitamin B12-substitutive compounds or inactive vitamin B12 analogues (or both), the observed correlation coefficient between the methods in the foods tested was excellent (r = 0.99, y = 1.2x ? 1.1, n = 9). The Chemiluminescence method was suitable for the determination of vitamin B12 in foods as well as in serum and was simpler (fully automated) and more rapid (180 samples analyzed per hour), highly selective (use of intrinsic factor, the most specific vitamin B12-binding protein), and reproducible (coefficients of variation of 1.2?6.7%) than the microbiological method. Keywords: Vitamin B12; bioassay; Chemiluminescence; intrinsic factor; food