Mikihito Kanou

Mid-infrared spectroscopic measurement of ionic dissociative materials in the metabolic pathway.

We determine the pH dependency of the mid-infrared spectra in aqueous solution of the organic dissociative materials in the metabolic pathway: saccharide phosphates (G6P, F6P), adenosine, and its phosphates (ATP, ADP, AMP). The series of molar absorbance spectra for these reagents were obtained in a pH range of about 2 to 11 with a Fourier transform infrared (FT-IR) spectrometer equipped with a horizontal diamond attenuated total reflection (ATR) sampling accessory. We also provide a method of infrared spectral extraction of ionic dissociative materials by performing a linear least-square fitting utilizing the formulas of ionic dissociation equilibrium shift, and we obtain the infrared spectrum of each ionic species of the dissociative materials: G6P−, G6P2−; F6P−, F6P2−; ATP2−, ATP3−, ATP4−; ADP−, ADP2−, ADP3−; AMP, AMP−, AMP2−; and adenosine+, adenosine0. The infrared spectral structure of each ionic species of the dissociative materials in the metabolic pathway are discussed. Additionally, the possibility for a quantification system of the concentrations of the organic dissociative materials in varying pH is suggested.

Influences of Monosaccharides and its Glycosidic Linkage on Infrared Spectral Characteristics of Disaccharides in Aqueous Solutions

The infrared spectral characteristics of ten different types of disaccharides (trehalose, kojibiose, nigerose, maltose, isomaltose, trehalulose, sucrose, turanose, maltulose, and palatinose) and five different types of monosaccharides (glucose, mannose, galactose, talose, and fructose) in aqueous solutions (H2O and D2O) were determined. The infrared spectra were collected using the Fourier transform infrared attenuated total reflectance (FT-IR/ATR) method and comparisons between the degrees of absorption band-shift of the saccharide spectra in the H2O solution with those in the D2O solution with respect to the saccharide concentrations were done. The study revealed that the wavenumber shifts in the bands of mono- and disaccharides in the H2O and D2O solutions could be used as an indicator of the level of interaction between the saccharides and water. The study also focused on the glycosidic linkage position and the constituent monosaccharides and found that they have a significant influence on the infrared spectroscopic characterization of disaccharides in an aqueous solution.

X-Ray Fluorescent and Mid-Infrared Spectroscopic Analysis of Tomato Leaves

This study aims to develop a simple, rapid, simultaneous and quantitative method for evaluating nutrimental elements of the plant vigor using X-ray fluorescent (XRF) and mid-infrared (MIR) spectroscopy. Tomato, which is one of the typical agricultural products cultivated by hydroponics, was used as the sample, and the leaves would be an index of the nutrimental conditions. We developed the quantitative methods to analyze the XRF and MIR spectroscopic information, and studied the effects of the cultivation conditions on the nutrient information between branches of a trunk. The experimental results presented a great potentiality to obtain the nutrient information on the chemical elements such as Ca and the organic components such as the nitrogen in the plural modes using the both spectroscopic methods. This study presents an important step in the development of XRF and MIR spectroscopic analysis of the plant vigor in the agricultural fields

Mid-infrared spectroscopic analysis of saccharides in aqueous solutions with sodium chloride

The infrared spectral characteristics of three different types of disaccharides (trehalose, maltose, and sucrose) and four different types of monosaccharides (glucose, mannose, galactose, and fructose) in aqueous solutions with sodium chloride (NaCl) were determined. The infrared spectra were obtained using the FT-IR/ATR method and the absorption intensities respected the interaction between the saccharide and water with NaCl were determined. This study also focused on not only the glycosidic linkage position and the constituent monosaccharides, but also the concentration of the saccharides and NaCl and found that they have a significant influence on the infrared spectroscopic characterization of the disaccharides in an aqueous solution with NaCl. The absorption intensities representing the interaction between a saccharide and water with NaCl were spectroscopically determined. Additionally, the applications of MIR spectroscopy to obtain information about saccharide–NaCl interactions in foods and biosystems were suggested. Graphical Abstract We experimentally extracted the spectral characteristics of the monosaccharides and the disaccharides affected by the interactions of saccharides–NaCl–water.

X-ray fluorescent and mid-infrared spectroscopic measurements of vigor information of tomato plant

The aim of this study is to develop a simple, rapid, simultaneous and quantitative spectroscopic method to measure the plant vigor of the tomatoes. The leaves of the tomato grown using some kinds of calcium (Ca) concentrations of the culture media were used as the samples for the spectroscopic measurements, because tomato is one of the typical agricultural products cultivated by hydroponics and the leaves would be an index of the nutrimental conditions. The X-ray fluorescent (XRF) spectroscopic characteristic represented the influences of Ca concentrations in media on the tomato vigor and the mid-infrared (MIR) spectroscopic characteristic showed the organic nutrient differences might be due to the variations of Ca concentrations in the culture medium. This study presents a great possibility to grasp the plant vigor in the agricultural fields using the XRF and MIR spectroscopic methods.

Mid-Infrared Spectroscopic Monitoring of Enzyme Reaction Associating with Ionic Dissociative Metabolites

Abstract A simultaneous quantification method of concentrations of ionic dissociative materials and pH value in the mixture solutions was developed using the mid-infrared spectra of the ionic components extracted from the aqueous solutions. Additionally, we constructed an enzyme reactor accessory equipped with an FT-IR system for the continuous and non-destructive measurement and monitored the enzyme reaction process from glucose 6-phosphate to fructose 6-phosphate with D-glucose-6-phosphate ketol-isomerase. The developed quantification method was applied to the spectroscopic information of the reactant mixture, and the simulated time course of the reactant concentrations and pH value consistently represented the theoretical ones.