銀電極を用いる塩化物イオンの析出，溶出の2段階電気分解にもとづくクーロメトリーを実施した．銀網電極を用いるバッチ法と，銀線を挿入したPTFE製チューブを用いるフロー法の2通りを試験した．バッチ法では，水溶液において，電解時間を500 sに限った場合，塩化物イオンの定量範囲が2×10^－4～2×10^－3 mol dm^－3（M）であったのに対して，メタノール・水混合溶媒を用いると，定量範囲は3×10^－5～3×10^－3 Mに拡張した．電解時間を延長して全電解が達成される濃度範囲は，水溶液では3×10^－4～2×10^－3 M（電解効率102±6％）で，検出限界は9.2×10^－5 Mであった．混合溶媒では1×10^－4～3×10^－3 M（電解効率105±2％）で，検出限界は2.6×10^－5 Mであった．一方，フロー法では，試料液の注入量20 μL，流量0.01 mL min^－1（電極通過時間約100 s）の条件において，8×10^－5～1×10^－3 M（電解効率97±3％）の範囲で定量可能であり，検出限界は7.8×10^－5 Mであった．

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高知県室戸市では水深320mの海中から海洋深層水(DSW)を取水している。DSWはその清浄性および多くのミネラルを含むことから, 様々な発酵食品に応用されている。今回, 清酒発酵に与えるDSWの影響を調べることを目的として, 小スケールでの清酒発酵試験(1-2L)を行った。従来からDSWを発酵中に添加することにより, 清酒の香気成分すなわち酢酸イソアミル, カプロン酸エチルおよびカプリル酸エチルの生成を亢進することが知られている。この現象のメカニズムを探る目的で, DSWを添加して発酵させた場合の酵母の遺伝子発現をcDNAマイクロアレイを用いて解析した。その結果, DSWの添加により高級アルコーレおよび脂肪酸の代謝, 生合成に関連する遺伝子の発現上昇が認められた。これらの発現上昇が清酒の香気成分の生成量を増加させたものと推察された。また, DSWを添加した清酒の小仕込を行い, 官能検査を実施したところ, NaClやDSWの主要ミネラルを添加した場合に比べて総合評価が有意に高いことが明らかとなった。さらに興味深いことに, NaClを単独添加した場合, ストレスに関連する遺伝子の発現が上昇することが見出された。一方, DSWを添加した場合, このストレス関連遺伝子の発現上昇は抑えられた。以上の結果からDSWを清酒醸造に応用することの重要性が示されたものと思われる。

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著者は小麦粉の製粉工程で大量に副生する小麦ふすまを有機酸水溶液で抽出することにより，抗癌·抗脂肪肝·抗酸化作用などの機能性のあるフィチン酸を得て，さらに，この残渣をAspergillus nigerやTrichoderma viride起源の酵素剤で処理することにより，抗酸化作用などの機能性のあるフェルラ酸を得る方法を開発した。フィチン酸は醤油製造の際にフィチンおりやイノシトールとなり，フェルラ酸は醤油·味噌·焼酎·ワインなどの製造に際して香気成分の前駆体となるので，醸造関係者にも大いに参考となるので解説頂いた。

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Recently, we have reported that dietary phytate depressed the rises in hepatic levels of lipids and in hepatic activities of lipogenic enzymes due to sucrose feeding. In this study, an experiment was conducted to investigate the effect of dietary level of phytate on cecum in rats. The weights of cecum and cecal content, and cecal levels of total protein and DNA enhanced as the dietary level of phytate was increased up to 5%. Ratio of protein to DNA did not change in the hypertrophic cecum induced by dietary phytate. The result indicates that the enlargement of cecum due to phytate intake mainly resulted from the increase in cell numbers, i.e. hyperplasia. In addition, dietary phytate elevated phosphate in cecal content and reduced pH in cecal content. Thus, the reactive phosphate groups on inositol ring might play an important role in hypertrophic effect of dietary phytate on cecum in rats.

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We previously prepared a hot water extract and a zinc-rich fraction from oyster and investigated the utilization of zinc from oysters. In the present study, a new oyster extract prepared from a mixture of the hot water extract and the zinc-rich fraction was examined in rats. In experiment 1, changes in the absorption rate and tissue distribution of zinc were examined under different level of sodium phytate administration. Five-week-old male Wistar rats were given diets containing 20 ppm of zinc as zinc sulfate for 29 days ; those diets were replaced and supplemented with graded levels (0 %, 0.2 %, 0.5 %, 1.0 % or 2.0 %) of sodium phytate. The rats fed a diet higher in sodium phytate showed lower tissue zinc concentrations in several tissues. In particular, the zinc concentrations in serum, tibia, ileum and hair responded remarkably to the declination in dietary sodium phytate. There was a negative linear relationship between zinc concentrations in the tissues (serum, tibia, ileum and hair) and dietary sodium phytate level from 0 % to 1.0 %. In experiment 2, effects of differences in zinc source on the absorption and tissue distribution of zinc in rats fed a diet containing sodium phytate were examined. Five-week-old male Wistar rats were given 1.0 % sodium phytate-supplemented diet containing 20 ppm of zinc as zinc sulfate or 3 types of oyster extracts for 29 days. Differences in dietary zinc source (zinc sulfate or oyster extract) did not significantly influence zinc concentrations in serum or various other tissues. The rats fed a diet containing zinc as a new oyster extract showed slightly higher zinc concentrations in several tissues (serum, tibia and ileum) than those fed a diet containing zinc as zinc sulfate or other oyster extracts. These findings suggest that the new oyster extract has higher zinc bioavailability than zinc sulfate or other oyster extracts.

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Accurate and precise determinations of chlorine and bromine in plastic samples were examined using combustion ion chromatography (CIC). The concentration of H₂O₂ as an absorption solution as well as the analytical methods with and without an internal standard of phosphate ion was optimized by a recovery test using standard solutions and certified reference materials (BCR-681 and NMIJ CRM 8137-a). When concentrated of H₂O₂ such as 1000 mg kg⁻¹, was applied to CIC analysis, quantitative recovery could be obtained. Since the internal standard of the phosphate ion was lost by gas bubbling during the combustion process, the analytical results revealed higher values beyond those expected. On the other hand, the analytical results involving the calibration method without any internal standard were in good agreement with the certified values. The developed method was applied to analyze for chlorine and bromine in certified reference materials made by ABS resin (NMIJ CRM 8155-a). The analytical results obtained by CIC were in good agreement with these by an instrumental neutron activation analysis (INAA) as a complimentary analytical method. The uncertainty for each of chlorine and bromine by CIC analysis of NMIJ CRM 8155-a was 1.6%, which was consistent with that obtained by INAA. The limits of quantification for CIC analysis with 30 mg of plastic sample were 1 mg kg⁻¹ for chlorine and 5 mg kg⁻¹ for bromine.

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大豆ホエーおよびその各種分画物の抗酸化作用とその機構について検討し, 以下の結果を得た.
1) 肝ミクロソームと脳ホモジネートの系における脂質の過酸化に対して, 大豆ホエーおよび各種分画物のすべてにおいて抑制作用が認められたが, これらの抗酸化作用の強さは, それぞれの実験系で異なっていたことから, 分画して最も強力な抗酸化作用を有する画分を確認するという方法では, 大豆ホエーの機能は説明がつかない部分もある可能性が示唆された.
2) 大豆ホエーおよび各種分画物の鉄に対するキレート能とDPPHラジカル消去能を測定したところ, 全ての試料にこれらの作用が見いだされた.鉄キレート能は大豆ホエーおよびその可溶性画分であるA画分で強く, 沈殿画分であるD画分で弱かった.その逆にDPPHラジカル消去能は, D画分で最も強くA画分で最も弱い結果となり, 鉄キレート作用の強さと逆相関関係にあった.
3) 大豆ホエーおよび各種分画物のフイチン酸含量とフェノール化合物含量を測定した結果これらの分布は各試料によって異なっており, キレート能にはフィチン酸が, ラジカル消去能にはフェノール化合物の働きがある程度関与していることが示された.これらの結果から, 大豆ホエーおよび各種分画物の抗酸化作用は, 複数の成分の相互作用, あるいは相乗作用によって発揮される可能性が考えられ, 天然の抗酸化剤としての有用性が示唆された.

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キンギョに米糠成分のフェルラ酸，γ-オリザノール，フィチン酸を経口投与し，生体防御能の変化をみた。上記成分投与（100 mg/kg体重/日以上）で，10日以内にリンパ球や顆粒球数の増加，顆粒球の貪食能・NBT還元活性およびNK様細胞活性が上昇した。γ‐オリザノールでは10日後に体表粘液の分泌が，フェルラ酸やフィチン酸では20日後に同リゾチーム活性が高まった。当該物質はキンギョの非特異的生体防御能を高めた。

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Objective: To determine the effects of animal and plant protein intake and protein restriction on phosphorus excretion in healthy young women.

Methods: Healthy young women were divided into four groups: normal (no dietary intervention), animal (animal protein intake), plant (plant protein intake), and low-protein (protein restriction) and subjected to a 3-day dietary intervention. Except in the normal group, vegetable intake was kept to a minimum to eliminate the effects of their constituent minerals. Based on the 3-day dietary records and 24-hour collected urine on day 3, the nutritional value, food group intake, and urinary components were evaluated.

Results: There was no significant difference in the protein and phosphorus intake between the normal, animal, and plant groups. However, urinary phosphorus excretion was significantly lower in the plant and low-protein groups than that in the normal and animal groups; there was no significant difference between the plant and low-protein groups, with similar levels of phosphorus excretion. Magnesium intake and legume intake were significantly higher in the plant group compared to the other groups.

Consideration & Conclusion: We showed that the plant protein diet reduced urinary phosphorus excretion to levels similar to that of the protein-restricted diet, while ensuring a protein intake comparable to that of the animal protein diet. We hypothesize that phytin and magnesium, which are related to the form of phosphorus in foods, are the factors that may explain these findings. Plant proteins may therefore be useful in the prevention of hyperphosphatemia.

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アロニア（Aronia melanocarpa E.）およびハスカップ（Lonicera caerulea L.）の果実には，アントシアニンが豊富に含まれている．これらの果実は，強い抗酸化性を有することが報告されており，活性酸素が関与する種々の病態に対して保護効果をもつ可能性がある．本研究では，アロニアおよびハスカップから調製したアントシアニン高含有抽出物（アロニアおよびハスカップ抽出物）の臭素酸カリウム誘発腎障害抑制効果を調べた．臭素酸カリウム投与後のラットの臓器重量を測定した結果，アロニアおよびハスカップ抽出物を摂取させたラットでは，腎組織重量が対照群と比べて有意な低値を示した．また，腹部大動脈血清成分分析においてもアロニア抽出物投与群では，対照と比較して腎障害マーカーのBUNとクレアチニン値が有意な低値を示し，肝障害マーカーのAST (GOT）とALT (GPT）も有意な低下を示した．アロニアおよびハスカップ抽出物は，血清および腎組織中の臭素酸カリウム投与によるORAC値の低下および腎組織中のTBARSの増加を軽減した．これらの結果から，アロニアおよびハスカップ抽出物は，臭素酸カリウム誘発腎障害·肝障害に対して抑制効果を示し，この抑制効果はアロニアおよびハスカップ抽出物が生体内で強い抗酸化性を発揮したことによることが示唆された．

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　The postprandial increase in blood triglyceride levels is an independent risk factor for coronary artery disease and a large number of studies has shown that a diet rich in vegetables may provide protection against many chronic diseases. Leaf vegetables generally contain β-carotene, zeaxanthin and chlorophyll including thylakoids. In this study, we investigated the bile acid-binding capacities of thylakoids in vitro and the suppressive effects of it before the administration of a lipid meal on postprandial hypertriglyceridemia in rats using oral fat tolerance/loading tests (OFTT). Consequently, thylakoids bound bile acids in a dose-dependent manner. Following the administration of the lipid meals, increases in the serum triglycerides levels were significantly reduced in rats fed 300 mg/kg bw of thylakoids just before lipid meals. Additionally, the area under the curve showed that a high-dose thylakoids significantly inhibited the absorption of dietary fat. Moreover, the level of fecal bile acid was significantly increased although there were no significant differences in the fecal volume and fecal total lipid levels.

　These results suggest that thylakoid intake before eating a lipid diet induces a suppressive effect of postprandial hypertriglyceridemia to defecate bile acid and confirmed the results of the health-promoting potential dietary thylakoids. This health benefit of thylakoids could be achieved by substantially increasing the consumption of vegetables.

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 Site amplification is one of the most important factors in strong ground motion prediction at construction sites. In ground motion calculation methods such as the stochastic Green's function method, seismic motions are first synthesized on an outcrop of engineering bedrock with an S-wave velocity of more than 400 m/s. Ground motions on the ground surface are then evaluated using the substructure method by independently modeling only the shallow part of the subsurface structure, using ground motions on the outcropped engineering bedrock as input motions. This approach sometimes yields inaccurate results because the coupling effect between the shallow and deep parts of the subsurface structure is ignored.
 In the present study, the calculation accuracy of the conventional substructure method is first investigated for various soil layers. A rigorous method that incorporates the coupling effect with the deep subsurface structure is then proposed based on the nonlinear substructure method in terms of velocity convolution integrals.
 As an example, synthesized surface motions calculated by the conventional substructure method and a full rigorous analysis are compared using the S-wave structure of the Osaka Plain, where the S-wave velocity between the seismic bedrock and overlying sediments varies abruptly, for deep soil layers of various thicknesses. Although the onset S-wave parts coincide for both methods, differences in the later phase of the waveforms are observed. These differences occur because the reflected waves from seismic bedrock transmitted from the shallow layer to the deep layer are essentially ignored in the conventional substructure method.
 Next, generalized soil models are used to assess errors in the conventional substructure method by varying three and fixing one of the following four parameters: the S-wave velocity just above the seismic bedrock, the S-wave velocity just above the engineering bedrock, and the thicknesses of the shallow and deep parts of the soil. The error index, FDE, is used to quantify the calculation accuracy of the conventional substructure method. The error becomes large when the thickness of the deep soil is small and the thickness of the shallow soil is large, due to the difference in the travel time of the waves reflected from the boundary of the seismic bedrock. The impedance ratio between the seismic rock and sediments also contributes to the error.
 In order to rigorously incorporate the coupling effect of the deep and shallow soil layers into the conventional substructure method, a frequency-dependent dynamic impedance function is added to the bottom layer, instead of the viscous boundary for the engineering bedrock. First, the dynamic impedance function on an outcrop of engineering bedrock that includes the deep part of the soil is calculated in the frequency domain. The nonlinear behavior of the shallow soil layer requires a seismic response analysis in the time domain. The frequency-dependent dynamic impedance function for the deep soil layer is converted into a time-domain impulse response, which is used in the convolution integral of the velocity in the time-domain analysis.
 The proposed method is applied to the ground motion evaluation using the subsurface structure of the Osaka Plain. The acceleration response time histories and the response spectra obtained by the proposed method coincide well with those obtained through a full rigorous analysis. In the case of the nonlinear analysis, the coupling effect decreases because of the hysteretic damping effects of the shallow soil. However, the results obtained using the proposed method have been verified to approximately coincide with those obtained through the full rigorous analysis, implying that the proposed method provides a rigorous solution that considers the coupling effect with the deep part of the subsurface structure.

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