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The principal 705 Japanese foods were selected from the Standard Tables of Food Composition in Japan — 2010 — (Standard Tables) because these foods are known to contain available carbohydrates including starch, glucose, fructose, sucrose maltose and/or lactose. Individual available carbohydrate contents were calculated and tabulated based both on the estimated saccharide (carbohydrate minus dietary fiber) content of each selected food in the Standard Tables and the starch and sugar content of the food included in The McCance and Widdowson’s The Composition of Foods, USDA National Nutrient Database for Standard Reference and other sources. Because the compiled tabulated form, the Japanese Starch and Sugars Presumptive Composition Tables (JSSPCT), is harmonized with the Standard Tables, one can utilize the data in the JSSPCT as a reference for research and other purposes until and after the Ministry of Education, Culture, Sports, Science and Technology or other national organization publishes the official tables for available carbohydrate composition of foods in Japan.

The preservative effects of different types of polyhydroxyl compounds on the stability of biocatalysts, β-amylase, pyruvate kinase and heat shock proteins, under dehydration stress were investigated. Polyhydroxyl compounds used in the present study were trehalose, sucrose, raffinose, maltose, lactose, glucose, glycerol, and dimethyl sulfoxide. The enzymatic activity of β-amylase was lost following both freeze-drying and air-drying; that of pyruvate kinase was lost only after air-drying. Non-reducing sugars, including trehalose, sucrose, and raffinose had marked preservative effects on the stability of these two biocatalysts. In contrast, glycerol caused the deterioration of their enzymatic activities. To our surprise, however, glycerol effectively retarded the inactivation of heat shock proteins, GroEL and Hsc73, caused by short-term dehydration. These findings are of considerable significance for understanding the interplay between heat shock proteins and the stress-induced accumulation of glycerol in anhydrobiotic organisms. Moreover, the utilization of non-reducing sugars as well as glycerol for storage of food materials and certain specific biocatalysts has been elucidated.

PurposeThe purpose of this paper is to examine ladies' linen fabrics produced in different regions – Japan, Italy, and Poland – to ascertain differences in mechanical, thermal, and air permeability properties.Design/methodology/approachThe paper investigates mechanical properties, air permeability, and thermal conductivity. The silhouettes of Polish, Italian, and Japanese linen fabrics are different. The thermal conductivities of the Polish linen fabrics are high. The levels of 72 elements were analyzed and remarkable differences were observed in the levels of 16 elements, including Li, Al, Si, Ti, Cr, Ni, Rb, and Y, Ag, among Polish, Italian linen fabrics, and linen fabrics made in Japan. Another ten elements were detected at some level in either the samples of Polish linen fabrics or linen fabrics made in Japan.FindingsThere are differences among the Polish, Italian, and linen fabrics made in Japan, but the differences are not remarkable.Research limitations/implicationsThis paper is a wide world regional study of linen characterisation.Practical implicationsAnother ten elements are detected at some level in either the samples of Polish linen fabrics or linen fabrics made in Japan. There are differences among the Polish, Italian, and linen fabrics made in Japan, but the differences are not remarkable.Originality/valueThe paper presents useful Measurement instrumentation, analysis and characterisation of linen fabrics from different regions of the world.

A previously developed current swimming pool for mice has been used to evaluate many food components that enhance endurance exercise performance. In this article, to improve reproducibility, reliability and sensitivity of this assay system, we improved the spout part to generate a uniform current and divided the pool into six lanes to avoid physical interference between swimming mice. The stability of the current flow was assessed by measuring the surface current speed and water volume from the spout part. Maximum swimming times of ddY and BALB/c mice were measured to assess the reproducibility of the maximum swimming time. The improvement in sensitivity compared to the original equipment was estimated under three physiological conditions: low carbohydrate diet feeding, low blood hemoglobin level, and carbohydrate supplementation during exercise. The new spout part improved uniformity and quick adjustment of surface current, yielding an increase of workload in a stepwise manner during swimming. Exercise workload was increased in proportion to surface current speed, as evidenced by cadence of kicks and serum lactic acid levels. The improved swimming pool showed higher reproducibility of swimming time until fatigue (p

Aromatic amine dehydrogenase was purified and characterized from Alcaligenes xylosoxidans IFO13495 grown on beta-phenylethylamine. The molecular mass of the enzyme was 95.5 kDa. The enzyme consisted of heterotetrameric subunits (alpha2beta2) with two different molecular masses of 42.3 kDa and 15.2 kDa. The N-terminal amino acid sequences of the alpha-subunit (42.3-kDa subunit) and the beta-subunit (15.2-kDa subunit) were DLPIEELXGGTRLPP and APAAGNKXPQMDDTA respectively. The enzyme had a quinone cofactor in the beta-subunit and showed a typical absorption spectrum of tryptophan tryptophylquinone-containing quinoprotein showing maxima at 435 nm in the oxidized form and 330 nm in the reduced form. The pH optima of the enzyme activity for histamine, tyramine, and beta-phenylethylamine were the same at 8.0. The enzyme retained full activity after incubation at 70 degrees C for 40 min. It readily oxidized various aromatic amines as well as some aliphatic amines. The Michaelis constants for phenazine methosulfate, beta-phenylethylamine, tyramine, and histamine were 48.1, 1.8, 6.9, and 171 microM respectively. The enzyme activity was strongly inhibited by carbonyl reagents. The enzyme could be stored without appreciable loss of enzyme activity at 4 degrees C for one month at least in phosphate buffer (pH 7.0).

We investigated the effect of the carbohydrate chain and two phosphate moieties on heat-induced aggregation of hen ovalbumin. The dephosphorylated form of ovalbumin was obtained by treating the original protein with acid phosphatase. The single carbohydrate chain was removed by digestion of heat-denatured ovalbumin with glycopeptidase F, and the resulting polypeptide without this carbohydrate chain was correctly refolded to acquire protease-resistance. Thermal unfolding can be approximated by a mechanism involving a two-state transition between the folded and unfolded states with a midpoint temperature of 76 degrees C for the original form, of 74 degrees C for the dephosphorylated form, and of 71 degrees C for the carbohydrate-free form. The conformational stability of the original form was higher than that of the carbohydrate-free form. When the three forms of ovalbumin were heated to 80 degrees C and then cooled rapidly in an ice bath, the polypeptide chains were compactly collapsed to metastable intermediates with secondary structures whose properties were indistinguishable. Upon incubation at 60 degrees C, renaturation was possible for a large portion of the intermediates of the original form, but for only a small portion of those of the carbohydrate-free form. Light scattering experiments showed that in the presence of sulfate anions, the intermediates of the carbohydrate-free form aggregated to a greater extent than did those of the original form. The intermediates of the carbohydrate-free form bound to the chaperonin GroEL with about 10-fold higher affinity than those of the original form. It follows that the carbohydrate chain and the two phosphate moieties do not affect hydrophobic collapse in the kinetic refolding of hen ovalbumin but play an important role in the slow rearrangement. They block the off-pathway reaction that competes with correct refolding by effectively decreasing surface hydrophobicity.

野草 (17科42種) を対象として, 悪臭指標物質の一つであるメタンチオール (CH3SH) に対する消臭力の有無を検索し, さらにその消臭力の比較検討を行った。野草から得られたメタノール抽出物5mgについて, ヘッドスペースガスクロマトグラフ法によりCH3SHに対する消臭率を求めた。その結果, 約1/3の14種の野草に, 銅クロロフィリンナトリウム (SCC) よりも高い消臭力が認められた。特に消臭率100%を示した野草は, オニアザミ, カワラヨモギ, タカサブロウ, ヒメジョン, カキドオシ, オオニシキソウ, キジムシロの7種類であった。これら7種の野草抽出物の中でも, タカサブロウはSCCの24倍, オニアザミ14倍, オオニシキソウ7倍, カワラヨモギが6倍となる高い消臭力であった。これらの野草が消臭性植物であるという報告はこれまでのところ見あたらない。したがって, これらの野草は新しく消臭効果の期待できる素材であることが示唆され, 今後その作用に寄与している成分の同定が必要と考えられる。

微生物全細胞のグルコース酸化活性を電気化学的に測定する方法を用いて, 微生物に及ぼす薬剤の影響について調べた. Escherichia coli IFO3301 (E. coli) やLactobacillus plantarum IFO14711 (L. plantarum) の細胞にエタノール, 過酸化水素, 次亜塩素酸のような薬剤を作用させると, 薬剤濃度の増加とともにグルコース酸化活性及びコロニー形成能が低下した. 両菌のグルコース酸化活性は, コロニー形成能に比べて薬剤感受性が高かった. Pseudomonas putida IFO14164 (P. putida) のグルコース酸化活性は, E. coli やL. plantarum と異なり, 薬剤感受性が低かった. P. putida 細胞に26%エタノール又は0.5%過酸化水素を30℃, 10分間作用させると, コロニー形成能は消失するが, グルコース酸化活性は95%エタノール又は3%過酸化水素処理でも約20%残存した. 対数増殖期のP. putida やE. coli 細胞のコロニー形成能及びグルコース酸化活性は, 定常期に比べて次亜塩素酸に対する感受性が高かった. 低濃度の次亜塩素酸でP. putida 細胞を処理すると, コロニー形成能の薬剤耐性は増大したが, グルコース酸化活性の耐性は低下した. E. coli では, 次亜塩素酸による前処理はコロニー形成能とグルコース酸化活性の両方の薬剤耐性を増大させた.

Five monoclonal antibodies (OVA-01, -02, -03, -04, -06) produced against irradiated ovalbumin were investigated in relation to the conformational change in the ovalbumin molecule induced by irradiation with Cobalt-60 γ-rays. Four antibodies (OVA-01, -02, -04, -06) recognized both native and irradiated ovalbumin, but OVA-03 reacted only with irradiated ovalbumin. These antibodies were classified by modified competitive ELISA, and their Kd values were determined by the Klotz equation. Epitope analyses were also performed on OVA-03 using CNBr-cleaved peptide fragments from ovalbumin, and it was confirmed that OVA-03 bound to the fragment corresponding to residues Val173-Met196 of the ovalbumin molecule that consists of internal β-sheet strand 3A and helix F1 containing one open turn. These results demonstrate that dramatic conformational changes in proteins can be induced or that some tertiary or secondary structures can be broken down by γ-ray irradiation, producing new antigenic sites. Keywords: Monoclonal...

The folding of heat-denatured ovalbumin, a non-inhibitory serpin with a molecular size of 45 kDa, was examined. Ovalbumin was heat-denatured at 80 degrees C under nonreducing conditions at pH 7.5 and then cooled either slowly or rapidly. Slow cooling allowed the heat-denatured ovalbumin to refold to its native structure with subsequent resistance to digestion by trypsin. Upon rapid cooling, by contrast, the heat-denatured molecules assumed the metastable non-native conformations that were susceptible to trypsin. The non-native species were marginally stable for several days at a low temperature, but the molecules were transformed slowly into the native conformation. Considering data from size-exclusion chromatography and from analyses of CD, intrinsic tryptophan fluorescence, and adsorption of the dye 1-anilinonaphthalene-8-sulfonate, we postulated that the non-native species that accumulated upon rapid cooling were compact but structureless globules with disordered side chains collectively as a folding intermediate. Temperature-jumped CD experiments revealed biphasic kinetics for the refolding process of heat-denatured ovalbumin, with the features of increasing and subsequently decreasing amplitude of the rapid and the slow phases, respectively, with the decrease in folding temperature. The temperature dependence of the refolding kinetics indicated that the yield of renaturation was maximal at about 55 degrees C. These findings suggested the kinetic partitioning of heat-denatured ovalbumin between alternative fates, slow renaturation to the native state and rapid collapse to the metastable intermediate state. Analysis of disulfide pairing revealed the formation of a scrambled form with non-native disulfide interactions in both the heat-denatured state and the intermediate state that accumulated upon rapid cooling, suggesting that non-native disulfide pairing is responsible for the kinetic barriers that retard the correct folding of ovalbumin.

Near-infrared spectroscopy (NIR) scanning from 1100 to 2500 nm was applied to measure the unfreezable water bound to egg white lysozyme and soluble starch. Two characteristic absorption bands corresponding to water molecules were changed into the second derivative difference spectra. In the changed spectra, the peaks at each lower and higher wavelength might be attributed to the freezable and unfreezable water, respectively. When the correlation coefficients between absorbances at wavelengths with maxima in the peaks attributable to the unfreezable water and the results of differential scanning calorimetry used as a reference analysis method of unfreezable water were calculated, the correlation coefficients at 1908, 1952 and 1992 nm assigned to the combination of the stretching and bending vibrations of OH were above 0.91 in both lysozyme and starch. Therefore, it can be concluded that the NIR second derivative difference spectra, in the region assigned to the combination of the stretching and bending vibrations of OH in water molecules, have potential for the measurements of the unfreezable water bound to egg white lysozyme and soluble starch used as model samples of food materials.

Polymerization caused by defective folding of heat-denatured ovalbumin was examined. A compactly misfolded ovalbumin that was produced by cooling heat-denatured protein rapidly tended to aggregate in the presence of salt. Two different forms of aggregates were observed as the concentration of salt was varied: a linear polymer at a physiological concentration and a massive agglomerate at a higher concentration. Salt-induced polymerization depended on the species of anion and the order of effectiveness followed the lyotropic series of Hofmeister. Defective folding of heat-denatured ovalbumin induced the exposure of cysteine residues in sequences located in the interior of the native protein. The misfolded ovalbumin, but not the native protein, bound to bovine BiP and stimulated its ATPase activity with the K(m) of 64 microM and the V(max) of 0.5 nmol/min per milligram. Measurement of surface plasmon resonance revealed that only the misfolded ovalbumin was recognized with the K(d) of 4.12 X 10(-8) M by the Fab fragment of a monoclonal antibody raised against hen ovalbumin, and its epitope was determined to be a hydrophobic segment in the beta-strand of central sheet A. Transmission electron microscopy showed that the linear polymerization was inhibited by the addition of bovine BiP and the Fab fragment. These results demonstrated that the compactly misfolded ovalbumin polymerized through hydrophobic interaction occurring among the areas exposed as a result of defective folding of the heat-denatured protein. Exposure of the region of, or adjacent to, the central beta-sheet A was required for axial contact among the misfolded molecules, suggesting that this process may be explained by reference to the mechanism proposed for loop-sheet polymerization in the Z type variant of a serpin alpha1-antitrypsin.

ブタ小腸保存中の悪臭成分メチルメルカプタン (MM) を生産する嫌気性菌の分離を試みた。分離数が最も多く, かっMM産生能が最も高かったのはProteus mirabilisであった。メチオニン添加による増菌培養でMM産生量は著しく促進された。このとき分離されたMM産生菌はすべてP. mirabilisであった。これらの結果はブタ小腸保存中に発生する悪臭成分MMの主要生産菌がP. mirabilisであることを示している。

Age-associated changes in the induction of heme oxygenase (HO-1) and heat shock protein 70 (HSP70) after the administration of paraquat were investigated in the liver of senescence-accelerated mice (SAMs). The extent of HO-1 and HSP70 induced in response to paraquat decreased significantly with age, and the level of oxidized proteins increased with age. Moreover, the extent of induced HSP70 was lower in mice that were prone to accelerated senescence (SAMP1/(/)Fky) than in mice that were resistant to accelerated senescence (SAMR1/Fky) of the same age. These results suggest that an age-associated decline in the levels of HO-1 and HSP70 enhanced oxidative damage during the aging process. Age-dependent changes in HO-1 and in the levels of oxidized proteins were examined in SAMP1/(/)Fky. The accumulation of oxidized proteins was suppressed when HO-1 was induced, but increased markedly after the induction of HO-1 decreased. Free iron, the residuum from heme degradation, might mediate free radical production. The role of HO-1 is discussed in relation to the oxidative damage associated with age.

This study was conducted to investigate the effect of five amino acids, aspartic acid, glutamic acid, histidine, cysteine and phenylalanine, and of two dipeptides, anserine and carnosine, on the uptake and transport of iron across monolayers of Caco-2 cells. Caco-2 cells were grown on polycarbonate membrane inserts in serum-free medium [DMEM plus ITS (5 mg/l insulin, 5 mg/l transferrin and 5 μg/l selenious acid)]. The anserine, carnosine, glutamic acid, histidine and aspartic acid, except for cysteine and phenylalanine, at 20 μM significantly increased the uptake and transport of iron. Iron uptake and rate of iron transport in the presence of aspartic acid at 20 μM were significantly greater than those of other test solutions. When the concentration of added carnosine, anserine, glutamic acid, histidine and phenylalanine was increased from 20 μM to 1 mM in the test solution, the uptake and transport of iron was further increased. The results of the present study indicated that aspartic acid, glutamic acid, histidine, and the dipeptides, anserine and carnosine, enhanced the uptake and transport of iron by Caco-2 cells.

The bioavailability of iron in ferrous sulfate and in hemosiderin, prepared from pig liver in the laboratory, was evaluated in terms of the “hemoglobin regeneration efficiency” (HRE) and hematological indices. The anemia was induced in rats by feeding a casein-based, iron-deficient diet for 1 week and by withdrawal of blood from the retroocular vein. The anemic rats were fed for an additional 6 weeks the iron-deficient diet or the same diet supplemented with ferrous sulfate or hemosiderin at 6, 12, 18, 24 mg iron/kg diet. After 2 weeks, there was no significant difference in the HRE of the anemic rats fed with either hemosiderin or ferrous sulfate diets (31-55% for hemosiderin-fed groups against 28-52% for ferrous sulfate-fed groups). Blood parameters, levels of nonheme iron in the liver and spleen and iron contents in the liver, spleen, kidneys, heart and lungs of the rats fed with the hemosiderin diet were not significantly different than those of the rats fed with the ferrous sulfate diet. No significant difference was observed between the two experimental diets regarding the levels of available iron when assessed by the in vitro digestion method. The results indicated that hemosiderin is a good nutritional source of iron.

Endogenous factors responsible for the textural characteristics of buckwheat products were studied. An analysis with various buckwheat samples showed that there were variations in protein, starch, amylose and amylopectin contents among the various buckwheat flours examined. The protein contents of the buckwheat flours were significantly negatively-correlated to the starch, amylose and amylopectin contents of buckwheat. A texturometric analysis showed that the springiness of heated-dough made from buckwheat flour was positively correlated to its starch content and amylopectin content, and the springiness and chewiness was negatively correlated to the protein content. Experiments adding isolated buckwheat protein or starch to buckwheat dough confirmed the above-mentioned correlation between texture and components. This study suggests that both the protein and starch present in buckwheat flour may be important factors responsible for the textural characteristics of buckwheat products.

Near-infrared (NIR) spectroscopy scanning from 1100 to 2500 nm was applied for the determinations of heme and nonheme iron in raw muscle meats. Ground meat samples were divided into two sets of 30 and 15 samples as a calibration and a prediction set, respectively. The multiple regression equations (MREs) established for the calibration set between the chemical analysis reference data and the second derivative data of the NIR spectra gave the multiple correlation coefficients of 0.966 and 0.923 for heme and nonheme iron contents, respectively. The best MREs were obtained with the NIR data recorded at wavelengths where NH groups in protein molecules and C–C and CH in the porphyrin ring of heme give absorption. The correlation coefficients between the data calculated from these MREs and the reference data for the prediction set were 0.991 and 0.906 for heme and nonheme iron contents, respectively. The results indicate that the NIR diffuse reflectance procedure is a technique which serves the need for rapid and simple heme and nonheme iron determinations, thereby allowing an in vitro estimation of bioavailability of iron in muscle meats.

The feasibility of near-infrared (NIR) diffuse reflectance spectroscopy scanning from 1100 to 2500 nm in the analyses of the amounts of moisture, protein, starch, amylose, and tannin in buckwheat flours was examined. Fifty ground samples comprised of 27 different cultivars harvested in 12 different countries were divided into two sets: 35 samples as a calibration set and 15 samples as a prediction set. The multiple regression equations (MREs) established between the second derivative NIR spectra data and the reference data, which were obtained by chemical analyses of the calibration set, gave multiple correlation coefficients of higher than 0.93 for moisture, protein, and starch, and workable standard error of predictions (SEPs) in relation to the reference standard deviation data. In contrast, the MREs for amylose and tannin were judged as unstable because the SEPs had no difference with their reference standard deviation data. The influential wavelengths were 1925 nm for water (assigned to the combination of the stretching and bending vibrations of hydroxyl [OH]), 2057 nm for protein (assigned to the combination of NH and amide II or III), and 2100 nm for starch (assigned to the combination of OH and CO). The obtained results indicated that the NIR procedure can be used as a nondestructive analysis method for rapid and simple measurement of the amounts of moisture, protein, and starch in buckwheat flours.

Near-infrared (NIR) transflectance spectroscopy scanning from 1100 nm to 2500 nm was applied for the determination of palmitic acid (C16:0), oleic acid (C18:1) and linoleic acid (C18:2), the major fatty acids in edible oils. Edible oil samples were divided into two sets: 95 and 46 samples as a calibration and a prediction set, respectively. The multiple regression equations (MREs) established for the calibration set between the reference data analyzed by gas chromatography (GC) and the NIR raw spectral data gave the multiple correlation coefficients of 0.996, 0.989 and 0.993 for C16:0, C18:1 and C18:2, respectively. The best MREs were established with the NIR raw spectral data recorded at 1724, 1756, 2140 and 2180 nm. The Fourier transform mid-infrared spectra of the standard C16:0, C18:1 and C18:2 supported the belief that the absorptions at these wavelengths were attributed to the CH2 of the straight carbon chain and the C=C of the unsaturated fatty acid. Standard errors of predictions between the data calculated from the best MREs and the reference data analyzed by GC for the prediction samples were 0.925%, 2.186% and 2.011%, and the correlation coefficients between those were larger than 0.99 for C16:0, C18:1 and C18:2, respectively. The obtained results indicate that the NIR procedure can potentially be used as a nondestructive analysis method for the purpose of rapid and simple determination of C16:0, C18:1 and C18:2 in edible oils.

Previous studies have shown that there are hematological abnormalities in selenium (Se)-deficient animals. This study examined the effects of Se deficiency on various minerals in serum and other tissues of male Wistar rats. The animals were given free access to either Torula yeast-based Se-deficient (SeD) diet or Se-adequate (SeA) (containing 0.1 mg Se/kg diet as sodium selenite) diet. Blood was sampled after 12 and 24 weeks, and the rats were killed after 24 weeks, for the analysis of minerals in serum, liver, kidney, heart, and spleen. Analyses showed that Se deficiency affected the concentrations of magnesium, calcium, iron, copper, and zinc in selected tissues and serum. During the entire feeding period, serum iron concentration was 40-58% greater in SeD rats compared with SeA rats. The transferrin saturation with iron was significantly greater in SeD rats than in SeA rats (57-60% versus 30-31%). Iron concentrations in the tissues ranged from 1.1 to 2.5 times higher in SeD rats than in SeA rats (p0.05). Similarly but to a lesser extent, the concentrations of zinc and magnesium were significantly greater in the serum of SeD rats compared with SeA rats, and the concentrations of calcium was significantly higher in kidney and spleen and of copper in liver, while the concentration of magnesium was significantly lower in liver and kidney. These results suggest that Se deficiency may cause a secondary overload of iron and unbalanced distribution of other minerals.

Previous studies have shown that selenium (Se) deficiency is associated with hematological abnormalities, which may result in an increased distribution of iron in various tissues. This report describes histological studies of the location of excess iron deposits in tissues. Male Wistar rats were fed a Torula yeast-based Se-deficient [Se(-)] or Se-adequate [Se(+); containing 0.1 mg Se/kg as sodium selenite] diet for 8 or 82 weeks. Excised tissues were embedded in either paraffin or epoxy resin. A dramatic increase was observed in iron deposition in the liver and kidneys of rats on the Se(-) diet. Prussian blue-stained sections under the light microscope showed iron deposits in the parenchymal cells and Kupffer cells of liver and in the proximal tubules of kidneys. The liver and kidneys of Se(-) rats had considerably altered morphology: lysosomes were enlarged and contained electron-dense areas. X-Ray microanalysis showed that the areas that corresponded to the lysosomes contained iron. No iron deposits were observed in sections of kidney and liver from rats fed the Se(+) diet. Thus, these studies identified subcellular sites of iron deposition in the liver and kidneys of Se(-) rats. These iron deposits may be an important factor in the pathogenesis of Se deficiency.

胸腺抽出物の高分子画分(HM)および数十種類の酸性または中性のタンパク質で構成されているDEAE吸着画分(DEAE-HM)にはハイブリドーマに対する細胞増殖促進活性があり,抗体産生量も増加させることが明らかになった

Age-associated changes in several antioxidative factors were studied in blood and liver from mice prone to accelerated senescence aged 0.7 to 1.4 years and mice resistant to accelerated senescence aged 1.0 to 2.1 years. In both strains, activities of hepatic glutathione peroxidase (GSH-Px) and glutathione-S-transferase (GST) decreased significantly with age, and the activity of superoxide dismutase (SOD), and the concentration of glutathione (GSH) in liver and blood cells tended to decrease with age. The GSH concentration in the plasma and blood cells, and the hepatic GST and SOD activities were significantly lower in the mice prone to senescence than other strain, but the hepatic GSH concentration and GSH-Px activity were similar in the two strains. These results suggest that GSH and hepatic antioxidative enzymes are associated to some extent with senescence in mice with accelerated senescence.

The effect was assessed of paraquat administration on the antioxidative defense mechanism in blood and liver. Ten-week-old senescence-accelerated mice were fed with either a 20% casein diet or the same diet supplemented with 200 ppm paraquat for 12 weeks. About 0.2 ml of blood withdrawn periodically from the supraorbital vein was assayed for the activities of antioxidative enzymes and oxidative damage. Blood and liver collected after decapitating the mice were equivalently treated at the end of the experimental period. Paraquat ingestion depressed the antioxidative enzyme activities, and increased the level of oxidized protein in erythrocytes and the thiobarbituric acid-reactive substance (TBARS) value in plasma. Similar changes were observed for the plasma and liver in the antioxidative enzyme activites, and in the level of oxidized protein and the TBARS value. These changes produced by paraquat administration were closely associated with accelerated aging leading to cell death. We discuss the effect of paraquat on senescence in mice, in relation to the oxidative damage caused.

食用油の品質劣化の判定基準として用いられているPOVを近赤外分光分析によって測定した.ヒドロペルオキシドのOH基に由来すると考えられる2076nmとトリアシルグリセロールのエステル結合の減少に起因するのではないかと考えられる2052nmを含む5個の波長を選び分析した.得られた検量式は,SEEが1.501meq/kgであり, MCCが0.980であった.未知試料を用い,この検量式から求めたPOVと滴定法により求めたPOVとの間の測定誤差は1.098meq/kgであった.このことから食用油のPOVをNIRによって非破壊的に,迅速に測定できる可能性が示された.

Porcine small intestine evolved a specific offensive odor only 0.5 to 1 day after storage at 20 degrees C. We investigated the effects of Houttuyniae cordata (dokudami), refinery final molasses (RFM), green tea, and brown sugar on the evolution of methylmercaptan and ethanol, which were the main components of the volatiles which evolved from porcine small intestine in storage. Furthermore, we determined their antibacterial effect and deodorant activity against methylmercaptan, as possible factors in reducing the offensive odor. Addition of those materials reduced the offensive odor during storage. In particular, dokudami, green tea, and RFM markedly suppressed the evolution of methylmercaptan. RFM was most effective in suppressing the growth of bacteria. Dokudami had the highest deodorant activity, comparable to that of perilla leaves. However, the retardation of methylmercaptan evolution in situ cannot be simply explained by either of deodorant or antibacterial effect. It seems likely that the combined action of both effects affects the evolution of methylmercaptan in situ.

A study was designed to assess the effects of a high-protein diet on the activities of several enzymes involved in the cellular antioxidative defence mechanism. Two strains of mice, a senescence-prone series (SAM-P/1) and a senescence-resistant series (SAM-R/1), were each divided into two groups, and fed either a control (20% casein) or a high-protein (40% casein) diet, respectively, for 11 months from the age of 2 months. Blood and liver were assayed for specific activities of catalase, superoxide dismutase (SOD), and glutathione peroxidase, and the levels of oxidized protein. Ingestion of the high-protein diet decreased the specific activity of catalase in the erythrocytes from both strains of mice, and decreased that of SOD in liver from both strains of mice; however the activity of SOD in erythrocytes from SAM-R/1 was increased. In accordance with these changes, ingestion of the high-protein diet produced an increase in the level of oxidized protein, compared with ingestion the control diet, in erythrocytes from SAM-R/1, and a much more significant increase in erythrocytes from SAM-P/1. There was also an increase in the level of oxidized protein in plasma from SAM-P/1. These results are largely, if not completely, consistent with the notion that high-protein ingestion accelerates the cellular aging process by augmenting the level of oxidized protein in erythrocytes.

ウシの凍結乾燥胸腺 (FDT) を入手し, アセトンにより脱脂後, 水抽出, 加熱処理し, 噴霧乾燥して低分子画分 (LMT) を得た。10% FDTもしくは2% LMTを含有する飼料を調製し, SHRもしくはWKYに3週齢後期から投与を開始した。6, 8, 10, 12週齢に非観血法により収縮期血圧を測定した結果, 8週齢以降, FDTもしくはLMTを摂取したSHRの血圧の上昇が低く抑えられた。しかし, WKYではFDTもしくはLMT摂取による血圧の変化はほとんどみられなかった。14～16週齢まで, FDTもしくはLMT含有飼料を投与して飼育した後, 全血および臓器を採取し, 臓器重量, 各種血清酵素, 血清タンバク質分画, 血清コレステロール, 脾細胞の幼若化等を調べた。SHRへのFDT投与により, 肝臓重量, 血清グロブリン, 血清コレステロール, 血清GPT活性, PRC等に変化が認められた。LMT投与では, 血清コレステロールの低下をみたが, その他の生理学的因子に変化はみられなかった。以上より, FDT中には, SHRの血圧上昇を抑制する複数の因子の存在が推測された。その作用機序は, SHRの高血圧症発症機序にかかわるものと推定された。

冷凍豚肉を解凍した時に遊離するドリップの一般性状と利用方法について検討した.(1) ドリップの主体は筋細胞内液で一部細胞外液が含まれている.一般組成は水分とタンパク質で全体の99%を構成し,タンパク質の含有量は,ももドリップの8.8%からロースドリップの12.0%までの範囲である.(2) ドリップの一般性状は筋肉部位によって異なり,ばら肉のそれはロース肉ともも肉のドリップの中間的な性状を示す.核酸関連物質,有機酸などは肉の部位毎の特徴をそのまま示している.(3) ドリップ自体を塩せきすると経時的に遊離アミノ酸が増加し,食味が向上することが確認された.(4) ソーセージに解凍ドリップを復元添加するとドリップ自体の塩せきの有無に関わらず食味および色調が顕著に向上することが判明した.

日常から食品の防臭, 抑臭に用いられている調味料, 香辛料などの食品類, ならびに抗酸化, 殺菌作用の期待される試薬類, 処理がブタ小腸の悪臭発生, 揮発性成分量, 一般細菌数に及ぼす影響を検討した。1) 多くの食品類に悪臭発生の抑制作用を認めた。とくにたまねぎ, しそ, みそ, しょうがじょうゆ, 緑茶や, 香辛料, ハーブ類のセージ, タイム, クロープ, ナールスパイス, セルフィーユ, レモンパームは効果が顕著であった。このうち, しょうがじょうゆ, 緑茶, クローブは同時に一般細菌の顕著な増殖抑制効果を示した。2) 抗酸化, キレート, 殺菌効果をもつ試薬類, 処理にも抑臭効果が認められた。とくにBHA, EDTA, 昇こう, フェノールは官能評価, 一般細菌数の結果とも優れていた。3) 抑臭効果を有する食品類添加の際の一般細菌数, 揮発性成分量には統一した傾向は見られなかった. 官能的な効果が悪臭発生の抑制や矯臭などさまざまな因子の結果であることを示唆している。4) 抗酸化剤, キレート剤, 殺菌剤ならびに関連処理では官能評価に対応して主要揮発性成分量, 一般細菌数ともに減少した。ブタ小腸保存中の悪臭が, おもに微生物による腐敗や発酵の結果生成する揮発性成分, とくにイオウ化合物やアルコール類の生成に起因することが示された。

ハム,ソーセージの品質は塩漬条件ばかりでなく,煮熟条件によっても影響されることから,煮熟条件がハム,ソーセージの諸成分や食味に与える影響について検討した.塩漬肉を煮熟するときの温度,時間により,ソーセージのpH,残存亜硝酸根量,色調,遊離アミノ酸量,食味に種々の違いの生じることが認められた.煮熟によりソーセージのpHは上昇した.残存亜硝酸根は温度に依存して速やかに減少した.ソーセージの色調は亜硝酸塩添加系で優れていた.塩漬肉を55℃, 65℃, 80℃で煮熟を行なった結果,試料中の遊離アミノ酸量は,55℃で最も多く,65℃以上では,加熱分解により減少することが認められた.煮熟条件をかえて調製した試料の食味について,官能検査を実施した結果,亜硝酸塩使用の有無も食味の評価に影響を及ぼすことが認められた.

Proteolytic enzyme (s) was partially purified from a crude extract of acetone-dried powder of ginger rhizome. The purified preparation gave a single main protein band of approximately 30, 000 Da. on SDS-polyacrylamide gel electrophoresis and hydrolyzed casein (proteinase activity) and type 1 collagen from bovine achilles tendon (collagenase activity). The collagenase activity of ginger was not affected by addition of EDTA, which it is known to be a potent inhibitor of collagenases from other sources, but was inhibited by HgCl2. The proteinase and collagenase activities of the ginger preparation decreased at a similar rate during heat-treatment. These results are interpreted to indicate that ginger rhizome contains a single enzyme which has both proteinase and collagenase activities.

著者らは,野草から新しい防臭あるいは消臭成分を見出すための予備的な探査研究として,特に身近に自生する20種類の野草について,悪臭指標物質であるCH3SHに対する消臭活性を求めた.消臭活性はCH3SHに対する消臭率をヘッドスペースガスクロマトグラフ法により求めた.それらの中で顕著な消臭活性を示したのは,タンポポ,オニノゲシ,ノアザミ,クマザサ,スギナ,ドクダミであり,それぞれの消臭率は97.5%,88.6%,90.2%,87.5%,93.7%,98.3%であった.これらの野草の消臭性に関する報告は,これまでにドクダミ以外には見あたらない.

Chromium (Cr) is an essential trace element and is important for normal carbohydrate metabolism, and its deficiency in animals can cause a diabetic-like state. Human and experimental animal studies suggest that urinary Cr excretion is increased in diabetic populations. To investigate whether hyperglycemia-induced elevation of urinary Cr excretion reduces tissue Cr storage conditions, we assessed total Cr balance and Cr distribution in streptozotocin (STZ)-induced diabetic mice. Male C57BL mice were randomly assigned to STZ or control groups and their urine was collected 7, 14, 21 and 28 d after STZ injection. An inductively coupled plasma mass spectrometry instrument equipped with a dynamic reaction cell was used for determination of Cr in urine, plasma and tissues samples. The urinary excretions of Cr were 15.4+/-3.0 and 356+/-62 ng/d, and the renal Cr concentrations were 0.85+/-0.12 and 0.17+/-0.03 ng/mg for the control and diabetes groups, respectively (p

Zinc fortification of milk or soft drinks is usually used to combat zinc deficiencies in developing countries. Water-soluble zinc compounds, such as zinc sulfate or zinc citrate, are better absorbed but have an unacceptable taste. A micronised, dispersible zinc oxide (MDZnO), which does not have such a problem concerning taste, had higher solubility compared to ZnO (zinc oxide) in an artificial gastric solution. MDZnO was tested for its bioavailability using zinc-deficient Wistar rats. Prior to the experiment, rats were fed zinc-deficient diet for 3 wk and were orally administered control (distilled water) or zinc solutions (ZnO, ZnO+L-histidine (His), MDZnO, MDZnO+His, 1 mg zinc/kg or 3.2 mg His/kg body weight). Compared to ZnO, MDZnO showed a lag in peak time and a lengthy period of continued high plasma zinc concentration after the single oral administration of zinc compounds. Addition of His to MDZnO elevated serum zinc concentration. Serum zinc concentration (area under the curve) in rats administered MDZnO with His was significantly higher than in rats administered distilled water (p

塩漬時及び加熱処理時における,豚肉リン脂質(PL)の脂肪酸組成変化を明らかにするために,無菌的あるいは常法により亜硝酸塩添加及び無添加ソーセージを調製し検討した. 亜硝酸塩を添加した塩漬肉では,無添加系に比較して,無菌化塩漬,通常塩漬にかかわらず, PLの脂肪酸組成が変化した. PL,ホスファチジルコリン,ホスファチジルエタノールアミン中のC20:4, C18:2の含量は塩漬期間が延長するに従って減少した.また, PI値もこれらの変化に伴って減少した. 塩漬肉を加熱した時のPLの脂肪酸組成の変化は,無菌化処理肉の塩漬に比較して,通常塩漬で大きかった,このことから, PLの加熱時における変化に対して,微生物もなんらかの影響を与えているものと考えられた. 無菌化処理塩漬肉を加熱した場合,塩漬時と同様,亜硝酸塩無添加系に比較し,添加系で多価不飽和脂肪酸,特にC20:4, C18:2の減少が大きかった.このことから,加熱工程では亜硝酸塩と不飽和脂肪酸の反応が更に進行するように考えられた.

The effect of diets containing the cells of a phototrophic bacteria (PTB). Rhodopseudomonas capsulata, on lipid metabolism was examined in the serum and liver of rats. Three groups of rats, 5 animals per group, were fed either a diet containing 0.2 or 2.0% PTB cells or a casein-based control diet. Each diet contained 1% cholesterol (CHOL). While serum glucose levels were not significantly different between the control and the PTB groups, total CHOL and triacylglycerol (TG) in the serum were significantly lower in the PTB groups than in the control group (p less than 0.01). The ratio of serum HDL-CHOL to total serum CHOL was significantly higher in the PTB groups than in the control group (p less than 0.01). The 2.0% PTB group had lower hepatic TG (p less than 0.05) but higher hepatic CHOL (p less than 0.05) than did the control group. These results indicate that PTB cells contain a factor or factors which affect hepatic metabolism or secretion of CHOL.

Transglutaminase-catalyzed incorporation of L-lysine into wheat gliadin rendered the lysine-fortified protein poorly digestible in the in vitro tests. In rat feeding tests, however, the luminal leavings and excreta collected after administration of the [14C]lysine-fortified gliadin contained less than one-tenth of the radioactivity originally administered to rats. The enzymes, gamma-glutamylamine cyclotransferase and 5-oxoprolinase, known to occur in animal kidney are at least in part responsible for the observed high availability of isopeptide bound lysine. A novel enzyme which is capable of directly hydrolyzing the cross-linked isopeptide into component amino acids and peptides, "N epsilon-(gamma-glutamyl)lysine hydrolase" was found in the isolated microorganisms which can use the synthesized N epsilon-(gamma-glutamyl)lysine as their only source of carbon and nitrogen. The enzyme(s) appear to be effectively used for improving digestibility and availability of protein matrixes formed in normal metabolism and by heat and/or shear treatment commonly used in food processing.

An enzyme linked immunosorbent assay (ELISA) is described for the quantitative measurement of soya proteins in processed food products. The peptide fragment bearing an antigenicity against anti-glycinin (soya bean 11S globulin) antibody was purified from the trypsin digests of autoclaved glycinin and used as an indicator antigen for soya proteins. ELISA samples were prepared also by a combination of autoclaving and tryptic digestion. Quantitation of soya proteins by ELISA was found to resist interference by other food materials, and the ELISA signal was independent of soya bean cultivar. The ELISA method was evaluated on pork sausages which were prepared in the laboratory to contain 0 to 20·8% soya protein isolate. With commercial soya protein isolate as reference standard, the results showed that the detected amounts were in quantitative agreement with the added amounts of soya protein isolate.

Igisu-ryori was prepared with the seaweed Amikusa (Ceramium boydenii). Amikusa was boiled and dissolved in the rice bran water extracts, and the sol was coagulated by cooling. Major inorganic ions contained in the rice bran water extracts were K+, Mg2+, Ca2+, and PO43-. The effects of metallic cations on the gelling properties of Amikusa were examined by dissolving Amikusa in a solution of KCl, MaCl2 or CaCl2 containing 0.06% acetic acid during the boiling process. The increases in the concentration of KCl correlated with the increased Amikusa gel strength, but MaCl2 and CaCl2 had no significant effect. Amikusa was readily dissolved by NaH2PO4 or Na-phytate solution, which are compounds of phosphoric acid, but a gel did not form unless KCl was added to it. These results indicated that during the process of boiling the seaweed in the rice bran water extracts, the phosphoric acid radical of phytic acid affected the solubility of the seaweed, and the sol changed to a gel by cooling in the presence of K+.