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Tsujita T.,Ehime University | Shintani T.,Ehime Institute of Industrial Technology | Sato H.,Japan National Institute of Advanced Industrial Science and Technology
Food Chemistry | Year: 2014

Using α-amylase inhibition as a separation guide, polyphenolic compounds from peanut seed skin were prepared. During preparation, specific α-amylase inhibitory activities were increased about 4-fold. High-resolution MALDI-TOF mass spectra showed that the structure of this sample was a series of polyflavan-3-ols, up to 15-mer, composed of catechin/epicatechin units together with several afzelechin/epiafzelechin units and gallocatechin/epigallocatechin units. The observed precious mass values suggest that the polymers consist of both interflavanoid C-C linkages (A-type) and interflavanoid ether linkages (B-type). Oral administration of the polyphenol fraction to rats fed corn starch significantly suppressed an increase in blood glucose levels in a dose dependent manner. Administration of the polyphenol fraction to rats fed maltose or sucrose delayed the increase in blood glucose levels. These results suggest peanut seed skin contains polyphenols with strong α-amylase inhibitory activity, which retard absorption of carbohydrates and mainly function through inhibition of α-amylase. © 2013 Elsevier Ltd. All rights reserved. Source


Tsujita T.,Ehime University | Shintani T.,Ehime Institute of Industrial Technology | Sato H.,Japan National Institute of Advanced Industrial Science and Technology
Journal of Agricultural and Food Chemistry | Year: 2013

Using α-amylase inhibition as a separation guide, polyphenolic compounds from almond (Prunus dulcis) seed skin were purified using ultrafiltration and Sephadex LH-20 and ODS columns. The purified fraction specifically and strongly inhibited α-amylase; the IC50 value was 2.2 μg/mL for pig pancreatic α-amylase. The fraction contained about 62% of the total polyphenols, 33.8% flavanol-type tannins and 30% procyanidins. Oral administration of the polyphenol fraction to rats fed corn starch significantly suppressed an increase in blood glucose levels and area under the curve (AUC), in a dose-dependent manner. High-resolution MALDI-TOF mass spectra showed that the structure of this sample is a series of polyflavan-3-ol polymers composed of catechin/epicatechin units and gallocatechin/epigallocatechin units up to 11-mer with several interflavanoid ether linkages. The results suggest almond seed skin contains highly polymerized polyphenols with strong α-amylase inhibitory activity, which retard absorption of carbohydrate. © 2013 American Chemical Society. Source


Watanabe Y.,Ehime University | Torii E.,Ehime University | Ohno K.,Ehime Institute of Industrial Technology | Maeda K.,Maeda corporation
Nippon Shokuhin Kagaku Kogaku Kaishi | Year: 2011

This study investigated γ-amino butyric acid (GABA) barley seeds for its potential uses such as in foodstuffs. A simple method was designed to produce "mochi" barley containing a high concentration of GABA. Scaled seeds of "mochi" barley (Hordeum vulgare) were soaked in a glu-tamic acid solution. After draining off the solution, the processed seeds were allowed to stand at room tempera-ture overnight. During this process, glutamate decarboxy-lase in the mochi barley converted glutamic acid to GABA. For optimal conversion, seeds were scaled before soaking in a solution containing 0.3-1% glutamic acid at pH 4 to 8. Source


Wada Y.,Osaka University | Matsubara A.,Osaka University | Uchikata T.,Osaka University | Iwasaki Y.,Nagoya University | And 5 more authors.
Journal of Separation Science | Year: 2011

In this study, a high-throughput and high-sensitivity profiling system for β-cryptoxanthin (βCX) and β-cryptoxanthin fatty acid ester (βCXFA) was constructed by supercritical fluid chromatography (SFC) coupled with triple quadrupole mass spectrometry (QqQMS). βCX and nine βCXFAs were successfully separated within 20 min using a column packed with octadecylsilyl-bonded silica particles. The limit of detection was 540 fmol for the free form and 32-130 fmol for the esterified forms. These results demonstrate that both the throughput and the sensitivity of this SFC-QqQMS system are considerably higher than those of conventional methods. When this system was applied for the analysis of Citrus unshiu, βCX and five βCXFAs were directly detected with much simpler sample pre-preparation. The analysis of other citrus fruits indicated that the βCXFA profiles varied with their breed variety. Furthermore, gas chromatography-mass spectrometry was used to analyze total fatty acid profiles in C. unshiu, and the results revealed that the profiles of fatty acids located in βCXFA were distinct. This is the first report on the analysis of βCX and its fatty acid derivatives by SFC-QqQMS. The profiling system developed in this study will be a powerful tool for investigating xanthophyll fatty acid esters. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source


Fukugaichi S.,Ehime Institute of Industrial Technology | Fukugaichi S.,Ehime University | Matsue N.,Ehime University
Materials Chemistry and Physics | Year: 2015

Enhancement of the photocatalytic activity of TiO2 and its mechanism are important subjects in the field of catalysis. Under the coexistence of TiO2 with a diameter of about 20 nm, we synthesized faujasite X-type zeolite, and the product was made up of the composite of TiO2 and faujasite X-type zeolite. The composite had higher acetaldehyde photocatalytic decomposition activity than a corresponding mixture, and the activity of the composite was higher than that of TiO2 on TiO2 mass basis. The composite had higher UV light absorptivity than the corresponding mixture, and their absorption of UV light was mainly due to TiO2. The increased UV light absorptivity of the composite correlated to its increased acetaldehyde photocatalytic decomposition activity. © 2015 Elsevier B.V. Source

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