Tadahiro Nagata

Seitoku University

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Mayumi Ohnishi‐Kameyama

National Agriculture and Food Research Organization

Masahiro Suzuki

Gifu University of Medical Science

Yoshihiro Chuda

Fulbright Japan

Yasuhiro Takahata

Kyushu Okinawa Agricultural Research Center

Tojiro Tsushida

Miyagi University

Takahiro Noda

Hokkaido Agricultural Research Center

Mitsuru Yoshida

Kone (Switzerland)

Masahito Hayatsu

National Agriculture and Food Research Organization

Xiaojun Yan

Ningbo University

Makiko Takenaka

Tokyo Kasei Gakuin University

Cooperative Institutions

Food Research Institute

National Agriculture and Food Research Organization

Food Research Institute

Ministry of Agriculture, Forestry and Fisheries

The University of Tokyo

Ministry of Agriculture Forestry and Fisheries

Shizuoka University

Tohoku University

Kyoto University

Osaka University

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Synthesis of Branched Cycloisomaltooligosaccharides by the Action of Cyclodextrin Glucanotransferase

Journal of Applied Glycoscience (1997)

Tetsuya Oguma Toshiko Kurokawa Tadahiro Nagata Mayumi O-Kameyama Satoshi Kitao

10.11541/jag1994.44.37

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Caffeine, flavanol and amino acid contentents in leaves of hybrids and species of the section Dubiae in the genus Camellia.

Ikushugaku zasshi (1985)

Tadahiro Nagata Shinsuke Sakai

Caffeine, flavanol and amino acid contents in young leaves of first flush shoots of hybrids and species of section Dubiae in the genus Camellia were investigated. Based on these results, principal component anafysis was performed. All clones of hybrid combinations between C.sinensis and other species such as C.sasanqua and C.japonica contained caffeine, ECG (epicatechin gallate). EGCG (epigallocatechin gallate) and theanine. Since these compounds were not detected in C.sasanqua and C.japonica, they were considered to be suitable chemical markers for hybrids between a species of section Thea and a species of other sections. In chromatographic studies of flavanols, both C, vernalis and C.hiemalis were found to contain high EC (epicatechin) amounts as well as four unidentified components which were detected in C.sasanqua and its hybrids. Therefore, both speciescould be considered to be hybrids resulting from crosses between C.sasanqua and a species of section Calnellia. Chromatogram of C.miyagii and C.tenuiflora did not show these peaks, and there was significant and positive correlation between the flavanol pattern of the latter species and that of C.oleifera. In general, flavanol chromatograms of C.wabisuke with the exception of cv. 'Sukiya' were similar to those of species of the section Camellia. Furthermore, caffeine, EGCG and theanine were not detected in the clones of C.wabisuke. Thus, phytochemically it was difficult to consider that C.wabisuke was related to C.sinensis.

Camellia

Theaceae

10.1270/jsbbs1951.35.1

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Citations (17)

Differences in caffeine, flavanols and amino acids contents in leaves of cultivated species and hybrids in the genus Camellia

Japan Agricultural Research Quarterly JARQ (1986)

Tadahiro Nagata

Camellia

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Varietal Differences in Crude Protein, and Free and Hydrolyzed Amino Acid Compositions of Sweetpotato Roots.

Nippon Shokuhin Kagaku Kogaku Kaishi (1995)

Yasuhiro Takahata Takahiro Noda Tadahiro Nagata

Crude protein content, and free and hydrolyzed amino acid compositions of whole root flour of sweetpotato cultivars that included lines lacking β-amylase were investigated in 1990 and 1991. A statistic varietal difference in crude protein content was detected; however, the order of the rank was largely different between the two years. The amino acid composition of whole root flour was similar among the cultivars and their profile was almost the same as in previous reports, although the aspartic acid content varied most greatly among the cultivars. The most predominant free amino acid was always asparagine in every cultivar, whereas the total free amino acid content largely varied among the cultivars. There was a large varietal difference in free asparagine content, which was quite altered between 1990 and 1991. However, the correlation coefficients between free asparagine content and hydrolyzed aspartic acid content in both years were above 0.9. Thus, most of the variabilities in aspartic acid contents among cultivars were the results of the variations in free asparagine content.

Aspartic acid

10.3136/nskkk.42.362

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Citations (7)

Distribution of Potassium and Calcium in Sweet Potato by X-ray Analytical Microscope.

Nippon Shokuhin Kagaku Kogaku Kaishi (1998)

Masahiro Suzuki Tadahiro Nagata Katsumi Komaki

X線分析顕微鏡は,大気圧下で,試料の前処理なしに元素分布の測定が可能である.ただし,検出感度が低い,測定対象元素が限定されるなどの問題もある.今回本装置にてサツマイモなどのミネラル分布を測定し,以下の知見を得た.(1) サツマイモでは,カリウムとカルシウムの分布に差があり,カリウムは表皮が,カルシウムは皮層部が高濃度であった.対して,玄米,ジャガイモ,大豆では両ミネラルの分布に差は見られなかった.(2) 不均一系の食品材料でも実際のミネラル分布を正確に画像化できるかを確認するため,サツマイモの各部位のミネラル含有量を,ICP-AESにより定量した.その結果,分布画像と定量値は一致していることがわかった.(3) 今回の材料では,カリウムとカルシウムのみで明瞭な分布像が得られた.

10.3136/nskkk.45.735

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Citations (4)

A lanostane-type triterpene from a mushroom Daedalea dickinsii

Phytochemistry (1997)

Hirokazu Kawagishi Hang Li Osamu Tanno Shintaro Inoue Shoji Ikeda

Lanostane

10.1016/s0031-9422(97)00382-8

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Citations (22)

Structural Identification of Two Antioxidant Quinic Acid Derivatives from Garland (Chrysanthemum coronarium L.)

Journal of Agricultural and Food Chemistry (1996)

Yoshihiro Chuda Hiroshi Ono Mayumi Ohnishi‐Kameyama Tadahiro Nagata Tojiro Tsushida

The structures of a novel compound, 3,5-dicaffeoyl-4-succinylquinic acid, and the related compound 3,5-dicaffeoylquinic acid were determined by analysis of spectral data. These caffeoylquinic acid derivatives, with antioxidative activity, were isolated from the leaves of garland (Chrysanthemum coronarium L.). Keywords: Antioxidants, dicaffeoylquinic acids, Chrysanthemum coronarium

Quinic acid

Identification

10.1021/jf960182+

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Citations (86)

Effect of Dietary Steamed and Cured Sweet Potato Slices on Bowel Movement in Female Students

Nippon Shokuhin Kagaku Kogaku Kaishi (2014)

Naoko Mori Chiemi Asano Tadahiro Nagata Teruko Ito

干しいもの摂取が排便に及ぼす影響について平均年齢20±1歳の女子学生84名を対象とし，非摂取期2週間および摂取期2週間（干しいも100g/日）の単一群試験を実施した．被験者は，排便状況を毎日記録し1週間ごとに提出した．その際，食事調査と身体測定を受けた．また，週3日以上排便がない者を便秘群（15名），週4日以上排便のある者を非便秘群（69名）とし，群別に解析を行った．その結果，非摂取期と比較し摂取期では，被験者全体として排便日数，排便回数，排便量および放屁回数が有意に増加した．また便秘群では，排便日数および放屁回数が有意に増加したが，非便秘群では，放屁回数が有意に増加した以外に，他の項目での有意差は見られなかった．干しいもの摂取による排便促進効果を介入試験により示し，便秘の改善を確認したが，将来はプラセボ対照群を設定し，食事や長期摂取による影響を調べ，本試験結果を検証したい．

10.3136/nskkk.61.144

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Citations (1)

Analysis of Abscisic Acid in Tea Leaves and Changes in the Contents of Abscisic Acid during the 1st and 2nd Crop Seasons

Chagyo Kenkyu Hokoku (Tea Research Journal) (1985)

Tadahiro Nagata Shinsuke SAKAI

茶葉中ABAのGC-MSによる分析法を検討した。分析試料は茶葉の溶媒抽出液をセップパックシリカカラムにかけた後,ジアゾメタンによりメチル化して調製した。茶葉中の夾雑物の多さから,電子衝撃法の選択イオンモニタリングでは測定不能であったので,化学イオン化法によりm/Z261の(MH-H2O)イオンを用いて,ABA-Meを検出した。本法を用いて一番茶期,二番茶期について3種の葉位のABA含量を経時的に分析した。5月中旬から6月上旬までは第1次伸育葉中の上位2葉が,越冬葉より高かったが,6月中旬以降は大きな差がなかった。二番茶期は調査した3種の葉位ともほぼ同じような変動を示した。

10.5979/cha.1985.1

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Involvement of Two Plasmids in the Degradation of Carbaryl by Arthrobacter sp. Strain RC100

Applied and Environmental Microbiology (1999)

Masahito Hayatsu Motoko Hirano Tadahiro Nagata

ABSTRACT A bacterium capable of utilizing carbaryl (1-naphthyl N -methylcarbamate) as the sole carbon source was isolated from carbaryl-treated soil. This bacterium was characterized taxonomically as Arthrobacter and was designated strain RC100. RC100 hydrolyzes the N -methylcarbamate linkage to 1-naphthol, which was further metabolized via salicylate and gentisate. Strain RC100 harbored three plasmids (designated pRC1, pRC2, and pRC3). Mutants unable to degrade carbaryl arose at a high frequency after treating the culture with mitomycin C. All carbaryl-hydrolysis-deficient mutants (Cah − ) lacked pRC1, and all 1-naphthol-utilization-deficient mutants (Nat − ) lacked pRC2. The plasmid-free strain RC107 grew on gentisate as a carbon source. These two plasmids could be transferred to Cah − mutants or Nat − mutants by conjugation, resulting in the restoration of the Cah and Nah phenotypes.

Carbaryl

Strain (injury)

Arthrobacter

10.1128/aem.65.3.1015-1019.1999

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Citations (60)