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Viscosity measurement using a cone-and-plate rheometer is considered to provide an objective and reliable evaluation of thickening agents for dysphagia management. Here, we showed its measurement uncertainty in the context of an inter-laboratory study. Eight test samples (i.e., four viscosity standard liquids, one xanthan gum reagent powder, and three commercial thickening agent powders) were distributed to 10 laboratories in a blinded manner. According to the same standard operating procedure, each laboratory dissolved the xanthan gum or thickening agents at four concentrations (0.5-4.0 g/100 g) and then measured their viscosity (35-803 mPa∙s). As for the viscosity of the standard liquids, the grand means were 98-100% of the certified values, and the relative standard deviations for repeatability (RSD

Background Previous Japanese studies have led to the erroneous conclusion of antioxidant capacity (AOC) intakes of the overall Japanese diet due to limitations in the number and types of food measured, especially in rice and seafood intake. The aims of the study were to construct an AOC database of foods representative of the typical Japanese diet and to clarify the high contributors to AOC intake from the overall diet of the Japanese population. Methods Commonly consumed foods were estimated using 3-day dietary records (DRs) over the four seasons among 55 men and 58 women in Japan. To generate an AOC database suitable for the typical Japanese diet, hydrophilic (H-)/lipophilic (L-) oxygen radical absorbance capacity (ORAC) values of foods in each food group were measured via validated methods using the food intake rankings. Subsequently, we estimated the AOC intake and the AOC characteristics of a typical Japanese diet. Results Of 989 food items consumed by the participants, 189 food items were measured, which covered 78.8% of the total food intake. The most commonly consumed types of antioxidant-containing food were tea, soybean products, coffee, and rice according to H-ORAC, and soybean products, fish and shellfish, vegetables, and algae according to L-ORAC. Conclusions The characteristics of high AOC intake in rice and seafood more appropriately reflected the Japanese-style diet. Further studies are expected to clarify the association between food-derived AOC and its role in preventing or ameliorating lifestyle-related diseases.

To provide reliable data for high quality epidemiological studies examining the relationship between health and antioxidant intake from daily foods, 107 plant-derived food items (12 rice, bread and noodles, 5 potatoes and starches, 9 pulses, 6 nuts/seeds, 29 vegetables, 22 fruits, 5 mushrooms, 7 algae, and 12 beverages) were selected as commonly consumed foods in Japan based on dietary records, and their antioxidant capacities were evaluated by validated hydrophilic- and lipophilic-oxygen radical absorbance capacity (H-ORAC and L-ORAC) methods. The food items covered more than 60% of total food intake for each category on a weight basis. The H-ORAC and L-ORAC values were widely distributed at 0-210 and 0-30 μmol-Trolox equivalent/g, respectively. The foods possessing potent antioxidant capacities were found in vegetables and fruits as well as other plant-derived foods. In most foods measured, the H-ORAC values were much larger than the L-ORAC values, except for certain kinds of pulses, nuts/seeds, mushrooms, and algae. The ORAC data shown here is sufficient to accurately estimate the antioxidant intake from plant-derived foods in Japan, and should be useful in future epidemiological studies aiming to clarify the biological significance of ORAC values.

Dish-based nutrient profile analyses are essential for setting goals to achieve a balanced diet. In 2014, the Japanese government proposed the “Healthy Meal” criteria, which requires a salt content of 3 g/650 kcal per meal. To examine the current intake status of a nationally representative sample, we conducted a series of secondary analyses of the 2014–2018 National Health and Nutrition Survey data. Participants (aged 18–74 years) were grouped as “high-salt” consumers if their salt intake was 3 g/650 kcal or higher and “adequate” consumers if they consumed less than 3 g/650 kcal. A total of 13,615 participants were identified as “adequate” consumers and 22,300 as “high-salt” consumers. The median salt intake in the “high-salt” group was 11.3 g/day, while that in the “adequate” group was 7.5 g/day. Almost all dishes consumed by the “adequate” group had significantly high energy and fat content but low salt content, compared with those consumed by the “high-salt” group. For example, the median energy, fat, and salt contents in the main dishes consumed by the “adequate” group were 173 kcal, 10.4 g, and 0.9 g/dish, respectively, while those in the main dishes consumed by the “high-salt” group were 159 kcal, 8.9 g, and 1.1 g/dish, respectively. Examples of balanced dishes that are low in both salt and fat content can be proposed to help improve the Japanese consumers’ dietary behavior.

Proper determination of the amount of selenium (Se) in infant formula is important to maintain the health of non-breastfed babies. A simple dilute-and-shoot method using inductively coupled plasma mass spectrometry (ICP-MS) to determine Se in liquid infant formula was developed and validated in single- and cross-laboratory validations. Samples were diluted in an aqueous solution containing a surfactant and acetic acid and then directly introduced to ICP-MS without microwave digestion. For ICP-MS detection modes, the no-gas mode was preferable to the helium mode. In the single-laboratory validation, the developed method indicated excellent linearity (R2 = 0.998), satisfactory limit of quantification (instrumental 0.03 ng/mL, method 0.075 μg/100 mL), and acceptable accuracy (relative standard deviation = 1.8–6.6%, recovery = 87–101%) in a recovery test at three spike levels. Furthermore, the result of a certified standard reference material (SRM 1849a) suggested good trueness (115%). In the cross-laboratory validation between two laboratories, the reproducibility of the dilute-and-shoot method was comparable with the authentic microwave digestion method based on the AOAC official method. The ratios of observed Se by the dilute-and-shoot method to that of the microwave digestion method ranged from 81 to 113%. These data suggest that the method presented here is a reliable method to determine Se content in liquid infant formula.

Graphical abstract, Highlights • The contents of glabridin and medical component glycyrrhizin were analyzed in herbal medicines and health foods containing licorice. • A small amount of glycyrrhizin was detected in some of health foods. • Estrogenic activity was detected in some of health food ingredients and health foods. • Antioxidant activity was detected in all the materials. • Hepatic CYP activity, liver and uterine weights in estrogen deficient mice are also valuable for the safety evaluation of estrogenic ingredients., Focusing on licorice, a highly used raw material in health foods, quantitative analysis of functional/medicinal components and a safety and functional evaluation was carried out for herbal medicines, health food ingredients, and so-called health foods. A functional component, glabridin, was detected in herbal medicines from Glycyrrhiza glabra and G. inflata, health food ingredients, and in commercially available health foods that contain licorice. Likewise, glycyrrhizin, a medicinal component, was detected in these sources, except in licorice oil extract. Estrogen activity in vitro was detected in some of the herbal medicines, health food ingredients, and in health foods containing licorice. In the in vivo study, liver weight in ovariectomized (OVX) mice treated with licorice oil extract was significantly higher than that in OVX and sham mice in a dose dependent manner. These results suggest that excessive intake of licorice oil extract from health foods should be avoided, even though these ingredients might be beneficial for medical use in order to maintain bone health in postmenopausal women. Measurement of hepatic cytochrome P-450 (CYP) activity, reproductive organ weight, and fat and bone mass in OVX mice was considered useful for evaluating the safety and efficacy of estrogenic health food ingredients derived from herbal medicines.

This paper deals with proficiency testing schemes for food nutrition analysis in Japan. In schemes in 2017 and 2018, 65 and 73 organizations participated, respectively, and more than 70% of the participants were public organizations responsible for a nutrition-labeling compliance test. The food matrices were pork and chicken sausages, and analytes were protein, fat, ash, moisture, carbohydrate, energy, sodium, salt equivalent, calcium (2018 only), and iron (2018 only). The organizations reporting inadequate laboratory values in one or more nutrients for mandatory declaration (energy, protein, fat, carbohydrate, or salt equivalent) were 11 and 15% of all organizations and 9 and 13% of public organizations in the 2017 and 2018 schemes, respectively. The approximate relative standard deviations for proficiency assessment (RSDr) were as follows: protein, 2%; fat, 3%; ash, 2%; moisture, 0.5%; carbohydrate, 9%; energy, 1%; sodium (salt equivalent), 4%; calcium, 7%; and iron, 7%. Notably, the large RSDr value for carbohydrate may cause inconsistency among laboratories in compliance tests for foods containing several grams or less of carbohydrate per 100 grams.

We evaluated the influence of pine bark extract (PBE) on organs, the cytochrome-P450 (CYP) activities in liver and estrogenic effects in normal and ovariectomized (OVX) female mice. The PBE did not affect organ weights and liver-function indexes (activities of alkaline phosphatase, aspartate amino transferase, and alanine amino transferase) at doses; 0.04%, 0.4%, and 2.0% PBE in the diet, in normal and OVX female mice. In the OVX mice, CYP1A1 activity was significantly higher in the 0.4% and 2.0% PBE groups than in the OVX control group, and in the 0.4% and 2.0% PBE groups were significantly higher than in the 0.04% PBE group. CYP1A2 and 3A4 activities were significantly higher in the 2.0% PBE group than in all other groups. The PBE did not affect uterine weight and femoral bone mineral density at all PBE doses. These results showed that the dose of PBE at the recommended human intake, had no toxic and estrogenic effects in normal female and OVX mice, however, it may need attention to use the excess intake of PBE with some drugs in postmenopausal women.

Vitamins are essential nutrients for human beings. Therefore, accurate determination of vitamin levels in foodstuffs is vital to confirm the proper intake of vitamins. The microbiological assay (MBA), which is used worldwide for the determination of several vitamins in foodstuffs, is very sensitive and can determine ng/mL levels of vitamins. However, the correlation between vitamin concentrations in a sample solution and the plotted growth is usually shown as a sigmoid curve. Therefore, a calibration curve derived from a linear regression may lead to error. In this study, we evaluated the effects of various models (linear, quadratic, and cubic regression models and a four-parameter logistic model (4PLM)) for calibration curve construction on the determination of vitamin B6 in infant formula. Among the four models, the calibration curve constructed with 4PLM was the most reliable for vitamin B6 determination. Moreover, the calibration curve based on 4PLM showed robustness for extrapolation; even if the vitamin concentration in the sample solution deviated from the range of the standard solution, a reasonable result could be obtained. Similarly, the 4PLM calibration curve was the most reliable for niacin determination. We conclude that 4PLM should be used for calibration curve construction to improve the reliability of vitamin determination in foodstuffs using MBA.

OBJECTIVES: Dish based nutrient profile analyses are essential in setting goals to achieve a balanced diet. The Japanese enjoy longevity, but their current diet is still high in salt, which was 10.1g/day among adults in the 2019 National Health and Nutrition Survey. In 2013, the Japanese government's “Health Meal” proposed the salt content of 3g/650 kcal per meal. However, studies are scarce regarding the nutrient profiles of the dishes eaten by the general population, especially who exceed the current standard. In order to examine the current achievement status and related nutritional problems among a nationally representative sample, we conducted the secondary analyses of the 2013–2018 National Health and Nutrition Survey data. METHODS: Dietary data from 35,915 participants in the 2013–2018 National Health and Nutrition Survey aged 18–74 years who ate three meals on the survey day, were applied for analyses. We extracted 554,257 dishes from each meal, and categorized them according to the definition of “staple dish” (grain dish), “main dish”(meat, fish, eggs, or beans), and “side dish”(vegetables, seaweeds, potatoes, or mushrooms) shown in the 2005 “Japanese Food Guide Spinning Top”. Participants were grouped as “high salt” consumers if their intake were 3g/650kcal or higher, and “adequate” consumers if they consumed less. The nutrient profile of each dish category was compared between the two groups by using the Wilcoxon's signed rank test. RESULTS: 22 300 participants were identified as “high salt” and 13 615 as “adequate”. The mean age of the “high salt” group (53.2 years) was higher than the “adequate” group (50.5 years), but their mean energy intake was similar (1901 and 2081 kcal/day, respectively). The mean salt intake in the “high salt” group was 11.8 g/day and the “adequate” group was 7.7 g/day. Among the dishes, 59 936 were categorized as “staple dish”, 47 081 as “main dish”, 45 828 as “side dish”, 30 151 as “combined dish”, and 371 261 as “miscellaneous”. Except for “staple dish”, dishes consumed by the “high salt” group were significantly low in energy and fat but high in salt, compared to the “adequate”. CONCLUSIONS: Older participants were more likely to consume dishes high in salt, but low in fat. Examples of balanced dishes low in both salt and fat could be proposed for further diet modification. FUNDING SOURCES: Ministry of Health, Labour and Welfare research grant.

In HPLC analyses of soluble dietary fiber, desalting processes using open, mixed-bed ion-exchange columns are time-consuming and labor-intensive. We developed and validated a simple desalting method using tandem cation/anion exchange SPE cartridges. We found that combining Bond Elut Jr SCX (upstream) and Bond Elut PSA (downstream) cartridges provided adequate desalting of test solutions. The developed method was then validated in an inter-laboratory study. Five test samples were prepared by mixing food matrixes with purified soluble dietary fiber and treated to generate solutions to test the desalting process. These solutions were then analyzed by eight different laboratories. The results demonstrated that the developed method is simple and reliable for desalting samples containing 140 to 945 mg/100 mL of soluble dietary fiber in preparation for HPLC analysis of soluble dietary fiber.

Numerous Foods with Function Claims that contain the extract of Pueraria flower (kudzu) isoflavones (PFI) are available in the Japanese market. These are labelled with function claims of reducing visceral fat. However, these foods have not undergone proper safety assessment such as the evaluation of their oestrogenic activity and effects on drug-metabolising enzymes (cytochrome P-450: CYP) in the liver. This study evaluated the estrogenic effect and the hepatic CYP activity and mRNA expression in normal female mice as a safety assessment of PFI (Experiment 1). In addition, the bone mineral density and visceral fat weight in ovariectomised mice (OVX) compared to soy isoflavones (SI) was evaluated to assess the efficacy of PFI (Experiment 2). OVX control fed a control diet, OVX fed a PFI diet (the recommended human intake of PFI), OVX fed a PFI20 diet (20- times the recommended PFI), OVX fed an SI diet (the recommended human intake of SI), and OVX fed an SI20 diet (20 -times the recommended intake of SI) for 28 days in Experiment 2. Body, liver, and visceral fat weights were not affected by the PFI, PFI20, SI, or SI20 diets. The hepatic CYP1A and CYP3A activities were elevated by the SI20 treatment. Ovariectomy-induced bone loss was inhibited by the SI20 treatment, but not by the PFI20 treatment. These results suggest that (1) PFI intake in human doses had no oestrogenic properties and did not affect CYP activity in the liver, (2) there was no evidence that PFI affects the amount of visceral fat in OVX mice.

The sum of hydrophilic antioxidants of 23 vegetables and 13 fruits commonly consumed in Japan was evaluated by a modified hydrophilic-oxygen radical absorbance capacity (H-ORAC) method. The “typical vegetable” and “typical fruit” in Japan contained hydrophilic antioxidants that are equivalent to 6.95 and 12.23 μmol of Trolox per g of the edible portion, respectively, on average. Hence, the daily intake of hydrophilic antioxidants from vegetables and fruits was estimated to be 4423 μmol Trolox equivalent (TE)/d based on data of the National Health and Nutrition Survey in Japan. However, the biological significance of these antioxidant values has not yet been clarified. To address this issue, our data will provide a foundation for high-quality epidemiological studies aimed at elucidating the relationship between daily intake of antioxidants and health. In addition, the comparison of the results of the H-ORAC assay with those of polyphenol content and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay was also studied. The H-ORAC values had a strong positive correlation with polyphenol contents ( r = 0.956), and were 1.0–18.2-times higher than the antioxidant capacities evaluated by the DPPH assay.

As a part of the development of an alternative to microbiological assay for vitamin B12, we performed a quantitative analysis of cyanocobalamin (CN-cbl) in a National Institute of Standards and Technology Standard Reference Material (SRM 3280) by HPLC. Using this method, the observed value (4.64 μg/g) of CN-cbl in SRM 3280 was found to be in good agreement with the certified value (4.80 μg/g). The accuracy was over 95%, with a corresponding measurement precision value of 5%. To evaluate the applicability of the method on commercial multivitamin tablets, the method was applied to a variety of these samples. The present method has a good accuracy and precision to evaluate CN-cbl with respect to all of the examined tablets.

A lipophilic oxygen radical absorbance capacity (L-ORAC) assay is an evaluation of the antioxidant capacity of solutions of lipophilic compounds. The concentrations of fluorescein, radical generator, and Trolox standard solutions were optimized to improve the precision of the assay. An interlaboratory study using two antioxidant solutions and three food extracts as test samples conducted in accordance with harmonized protocol demonstrated satisfactory L-ORAC measurements; the intermediate precision relative standard deviations (RSD(int)) ranged from 7.0 to 16.7%, the reproducibility relative standard deviations (RSD(R)) ranged from 14.8 to 19.4%, and the HorRat values ranged from 1.35 to 1.78.

OxHLIA is a cell-based antioxidant assay for evaluating inhibition of free radical-induced haemolysis in sheep erythrocytes by antioxidants. The original OxHLIA was performed in a test-tube format, and the degree of haemolysis was determined by absorbance of the supernatant after centrifugation. This made it difficult to evaluate large numbers of samples at the same time. Thus, we first showed here that the degree of haemolysis can be determined by turbidity of the erythrocyte suspension without centrifugation. We then developed OxHLIA in a 96-well plate format by adapting the turbidity method. There have already been some methodological studies on cell-based antioxidant assays using erythrocytes, and the method described here was comprised of the best mix of these earlier works with ingenious modifications. This plate method enables evaluation of large numbers of samples in small quantity at the same time with satisfactory precision and reproducibility.

Hydrophilic oxygen radical absorbance capacity (H-ORAC) is a method for evaluating antioxidant capacities of solutions of hydrophilic compounds. In this study, we improved the original method for H-ORAC determination, and evaluated the precision of the two improved methods (methods A and B) by interlaboratory studies using 5 antioxidant solutions and 5 food extracts as test samples. An interlaboratory study of method A, in accordance with the harmonized protocol, demonstrated satisfactory performance (intermediate precision relative standard deviations (RSD(int)) ranging from 4.6 to 18.8%; the reproducibility relative standard deviations (RSD(R)) ranging from 7.0 to 21.1%, and the HorRat values ranging from 0.40 to 1.93). However, methodological problems remained, and a further improved method, method B, was thus developed. An interlaboratory study of method B by 5 participating laboratories showed better intermediate precision and reproducibility (RSD(int) and RSD(R) ranging from 1.8 to 9.4%, and from 4.4 to 13.8%, respectively), and all HorRat values for the test samples were less than 1.3, suggesting good performance for the H-ORAC measurement.

大豆中のイソフラボンは構造的にエストロゲンと類似しており，弱いエストロゲン様作用を発揮する．2006年に，内閣府食品安全員会は特定保健用食品から摂取する大豆イソフラボンの上限量を，通常の食事に上乗せして30mg/日と設定した．しかしながら，大豆イソフラボンや大豆たんぱく質が含まれている，いわゆる健康食品には イソフラボンの許容上限量が設定されなかった．そこで我々は，大豆が原料となっている加工食品，特定保健用食品を5品目含む健康食品10品目について，大豆たんぱく質と大豆イソフラボン含有量をそれぞれ酵素免疫測定法（ELISA）と高速液体クロマトグラフ（HPLC）法で測定した。8品目における大豆たんぱく質量は表示の90－118％が確認され，ジュニア選手用のプロテインパウダー2品目においては表示の約半分量が定量された．大豆たんぱく質を含む特定保健用食品中には表示の90－122％の大豆イソフラボンが検出された。一方，表示のない大豆たんぱく質強化食品2品目には一回摂取目安量当たり30mgを超える大豆イソフラボンが検出された。このような食品をジュニア選手が過剰に摂取しないよう注意する必要があると考えられた。（オンラインのみ掲載）

本研究では，AOAC Internationalの基準に基づき，代表的な抗酸化物質を用いて抗酸化能測定法であるH-ORAC法の室間共同試験を行い，精度の調査を行った．室間共同試験には5種（（＋）-カテキン，Trolox, trans-フェルラ酸，ヘスペレチン，コーヒー酸）の抗酸化物質溶液および粉末を用いた．その結果，RSDrは溶液試料で5.9～13.2％，粉末試料で5.4～10.4％であり，RSDRは溶液試料で16.2～61.4％，粉末試料で16.9～33.2％であった．Trolox検量線の上限濃度である50μMから算出したHorRat値は溶液試料で1.48～5.62，粉末試料で1.54～3.03であり，本室間共同試験によって妥当性が確認されたとは言い難かった．室間再現性低下の要因として，プレートリーダーの特性に起因するウェル間での蛍光強度変化の差異挙げられ，これを低減することがH-ORAC法の室間再現性向上に重要と考えられた．

The antioxidant activity of a provitamin C agent, 2-O-beta-D-glucopyranosyl-L-ascorbic acid (AA-2betaG), was compared to that of 2-O-alpha-D-glucopyranosyl-L-ascorbic acid (AA-2G) and ascorbic acid (AA) using four in vitro methods, 1,1-diphenyl-picrylhydrazyl (DPPH) radical-scavenging assay, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS(*+))-scavenging assay, oxygen radical absorbance capacity (ORAC) assay, and 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH)-induced erythrocyte hemolysis inhibition assay. AA-2betaG slowly and continuously scavenged DPPH radicals and ABTS(*+) in roughly the same reaction profiles as AA-2G, whereas AA quenched these radicals immediately. In the ORAC assay and the hemolysis inhibition assay, AA-2betaG showed similar overall activities to AA-2G and to AA, although the reactivity of AA-2betaG against the peroxyl radical generated in both assays was lower than that of AA-2G and AA. These data indicate that AA-2betaG had roughly the same radical-scavenging properties as AA-2G, and a comprehensive in vitro antioxidant activity of AA-2betaG appeared to be comparable not only to that of AA-2G but also to that of AA.

1,4-dihydroxyl-2-naphtoic acid (DHNA) is a bifidogenic growth stimulator from Propionibacterium freudenreichii. According to a method described earlier, the peak area of DHNA measured by a high-performance liquid chromatography (HPLC) gradually increases with repeated analyses of the same sample. We hypothesized that the oxidizability of DHNA was the cause of poor precision. Therefore, we attempted to develop an improved method using dl-dithiothreitol (DTT) as a mobile phase additive. A DHNA standard solution (5 µg/ml) was analyzed five times in a row by either the original or the improved method. The relative standard deviation (R.S.D.) of the peak area was 37.0% and 1.6%, respectively. The linearity of the improved method was confirmed in the range of 0.25-10 µg/ml (R2 = 0.9998). These data indicate that the addition of DTT to the mobile phase improves precision of the analysis of DHNA by HPLC.

The 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging mechanism of 2-O-alpha-D-glucopyranosyl-L-ascorbic acid (AA-2G) was studied. We found two undefined products, named X and Y, in the reaction mixture of AA-2G and the DPPH radical under acidic conditions by HPLC analysis. The reaction mixture was further subjected to LC-MS analysis. X was found to be a covalent adduct of AA-2G and the DPPH radical. On the other hand, Y could not be identified, probably because it was a mixture. A time-course study of the radical-scavenging reaction revealed that one molecule of AA-2G scavenged one molecule of DPPH radical to generate an AA-2G radical, which readily reacted with another molecule of the DPPH radical to form a covalent adduct (X). Subsequently, this adduct slowly quenched a third molecule of the DPPH radical, resulting in reaction products (Y). Therefore, one molecule of AA-2G has only one oxidizable -OH group, but can scavenge three molecules of the DPPH radical. The radical-scavenging mechanism of AA-2G elucidated in this study should be useful in understanding the biological roles of AA-2G per se in the food and cosmetic fields.

2-O-alpha-D-glucopyranosyl-6-O-hexadecanoyl-L-ascorbic acid (6-sPalm-AA-2G), a novel stable lipophilic ascorbic acid derivative, was hydrolyzed to 2-O-alpha-D-glucopyranosyl-L-ascorbic acid (AA-2G), ascorbyl 6-palmitate (6-sPalm-AA) and ascorbic acid (AA) with alpha-glucosidase and lipase. An HPLC method for the simultaneous determination of AA, AA-2G, 6-sPalm-AA and 6-sPalm-AA-2G was developed using a cyanopropyl column with an isocratic solution of methanol-phosphate buffer (pH 2.1) (65:35, v/v) containing 20mg/l of dithiothreitol at a detection wavelength of 240 nm. The calibration curves were found to be linear in the range of 10-200 microM. Linear regression analysis of the data demonstrated the efficacy of the method in terms of precision and accuracy. This method was satisfactorily applied to the determination of 6-sPalm-AA-2G and its three metabolites in a 6-sPalm-AA-2G solution treated with purified enzymes or a small intestine post-mitochondrial supernatant and to the separation of novel stable lipophilic AA derivatives other than 6-sPalm-AA-2G and their metabolites. AA, AA-2G and other well-known stable AA derivatives, ascorbic acid 2-phosphate and ascorbic acid 2-sulfate, were also separated under the same conditions. The results show that the procedure is rapid and simple and that it can be employed for in vitro metabolic analysis of various AA derivatives.

The aim of this study was to characterize the antioxidant activity of three ascorbic acid (AA) derivatives O-substituted at the C-2 position of AA: ascorbic acid 2-glucoside (AA-2G), ascorbic acid 2-phosphate (AA-2P), and ascorbic acid 2-sulfate (AA-2S). The radical-scavenging activities of these AA derivatives and some common low molecular-weight antioxidants such as uric acid or glutathione against 1,1-diphenyl-picrylhydrazyl (DPPH) radical, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS+), or galvinoxyl radical were kinetically and stoichiometrically evaluated under pH-controlled conditions. Those AA derivatives slowly and continuously reacted with DPPH radical and ABTS+, but not with galvinoxyl radical. They effectively reacted with DPPH radical under acidic conditions and with ABTS+ under neutral conditions. In contrast, AA immediately quenched all species of radicals tested at all pH values investigated. The reactivity of Trolox, a water-soluble vitamin E analogue, was comparable to that of AA in terms of kinetics and stoichiometrics. Uric acid and glutathione exhibited long-lasting radical-scavenging activity against these radicals under certain pH conditions. The radical-scavenging profiles of AA derivatives were closer to those of uric acid and glutathione rather than to that of AA. The number of radicals scavenged by one molecule of AA derivatives, uric acid, or glutathione was equal to or greater than that by AA or Trolox under the appropriate conditions. These data suggest the potential usage of AA derivatives as radical scavengers.

We investigated the weight loss efficacy and safety of Citrus aurantium (CA, 1,000 mg/kg diet) along with usual levels of adrenergic stimulants in foods, i.e. caffeine (100 mg/kg diet) and/or tea catechins (500 mg/kg diet), in rats for 44 or 45 days. Even in combination with caffeine and tea catechins, the suppressive effect of CA against body fat accumulation was negligible, whereas no deleterious influences concerning cardiotoxicity were observed. Thus, although the efficacy of CA for weight loss seems to be questionable, no safety problems may occur even in people who habitually consume coffee and tea. However, it is noteworthy that the intake of CA markedly elevated the urinary excretion of adrenaline, and this was not affected by intake of caffeine and/or tea catechins at the usual levels. Therefore, the safety of CA intake with high levels of caffeine and tea catechins, especially in people at risk of heart disease, remains to be elucidated further.

The efficient extraction of antioxidants from food samples is necessary in order to accurately measure their antioxidant capacities. α-Tocopherol and gallic acid were spiked into samples of 5 lyophilized and pulverized vegetables and fruits (onion, cabbage, Satsuma mandarin orange, pumpkin, and spinach). The lipophilic and hydrophilic antioxidants in the samples were sequentially extracted with a mixed solvent of n-hexane and dichloromethane, and then with acetic acid-acidified aqueous methanol. Duplicate samples were extracted: one set was extracted using an automated pressurized liquid extraction apparatus, and the other set was extracted manually. Spiked α-tocopherol and gallic acid were recovered almost quantitatively in the extracted lipophilic and hydrophilic fractions, respectively, especially when pressurized liquid extraction was used. The expected increase in lipophilic oxygen radical absorbance capacity (L-ORAC) due to spiking with α-tocopherol, and the expected increase in 2,2-diphenyl-1-picrylhydrazyl radical scavenging activities and total polyphenol content due to spiking with gallic acid, were all recovered in high yield. Relatively low recoveries, as reflected in the hydrophilic ORAC (H-ORAC) value, were obtained following spiking with gallic acid, suggesting an interaction between gallic acid and endogenous antioxidants. The H-ORAC values of gallic acid-spiked samples were almost the same as those of postadded (spiked) samples. These results clearly indicate that lipophilic and hydrophilic antioxidants are effectively extracted from lyophilized food, especially when pressurized liquid extraction is used.

An adenosquamous-cell carcinoma of the bile duct is relatively rare. A 65-year-old woman was admitted to our hospital because of obstructive jaundice. Percutaneous transhepatic biliary drainage (PTBD) was performed. Cytology of the PTBD bile showed many keratinizing squamous carcinoma cells and a few clusters of adenocarcinoma cells. Cholangiography through the PTBD tube and endoscopic retrograde cholangiography, performed simultaneously, revealed irregular stenosis of the lower bile duct. Endoscopic ultrasonography also revealed a hyperechoic tumor and no choledochal stone. Pancreaticoduodenectomy was performed for the diagnosis of adenosquamous-cell carcinoma of the lower bile duct. Pathological examination of the tumor showed nodular invasive type of cholangioma and histological findings showed an adenosquamous-cell carcinoma. The patient has had hepatic metastasis for about one year, since the operation, but she is still alive and being treated with chemotherapy.

We experienced four cases of tumor forming pancreatitis. In this paper two out of four cases are presented with some notes on differential diagnosis from pancreatic cancer. Case 1, A 54-year-old man was admitted to the hospital with a doubt of pancreatic cancer with obstructive jaundice. Abdominal US, EUS, and ERCP revealed specific findings, and so we diagnosed the patient as having tumor forming pancreatitis. Case 2, A 53-year-old woman was admitted to the hospital with a suspicion of pancreatic tumor. The patients was diagnosed as tumor forming pancreatitis on EUS and ERCP. We studied the images of four patients of tumor forming pancreatitis retrospectively, and found that the most reliable image for diagnosis was ERCP, followed by US, and EUS. CT and angiography were comparatively poor in diagnosis. The reason might lie in that CT was uncapable of offering relieable differentiation of the density between the lesion and surrounding pancreas, and that angiography was not most appropriate for differentiation between hypovascular (pancreatic cancer) and isovascular areas (tumor forming pancreatitis).

症例は71歳の男性で, 平成6年8月17日肝内胆管癌に対して拡大肝左葉切除術を施行し, 術後外来にてfollow upしていたが, 平成8年7月29日早朝より大量に吐血し, 当科外来を受診した. 腹部CT, 超音波検査にて肝切離断端に腫瘍を認め, 肝内胆管癌術後再発が疑われた. 同腫瘍は十二指腸に浸潤しており, 上部消化管内視鏡検査でも十二指腸球部に腫瘍の露出を認め, 生検にて再発を確定しえた. 肝動脈造影で残肝に広範囲なtumor stainを認め, 根治的切除は不可能と判断した. 腫瘍により十二指腸は著明に狭窄し, 経口摂取は困難であった. 全身化学療法および放射線治療の後, 内視鏡を用いて病変部にcovered stentを留置したところ, 普通食の摂取が可能となり, 患者のQOLは著しく改善された. 約6か月後に癌死する直前まで, 十分な経口摂取が可能であった.

We improved the procedure for lipophilic-oxygen radical absorbance capacity (L-ORAC) measurement for better repeatability and intermediate precision. A sealing film was placed on the assay plate, and glass vials and microdispensers equipped with glass capillaries were used. The antioxidant capacities of food extracts can be evaluated by this method with nearly the same precision as antioxidant solutions.

Case 1: A 57-year-old man was admitted to the hospital because of a rest pain of the right lower limb. Angiography revealed that the right common iliac artery was obstructed for arteriosclerosis obliterans (ASO). The patient was complicated with ischemic heart disease, so we selected interventional therapy. Iliac revascularization by percutaneous transluminal angioplasty (PTA) and stenting were performed successfully. Case 2: A 73-year-old man was admitted to the hospital because of intermittent claudication and rest pain of the left lower limb. Angiography showed an obstruction of the left common iliac artery due to ASO. We revascularized the left common iliac artery with percutaneous transluminal angioplasty and stenting, with a successful outcome. Angioplasty and stenting is useful for iliac obstruction due to ASO. In the Western countries, the stenting has been applied to ASO of the pelvic or lower limb vein which does not respond to PTA alone and we can see favorable outcomes. This regimenwith angioplasty and stenting would promise to be a selectable therapy for ASO in the future.

Soy isoflavone is the generic name for the isoflavones found in soy. We determined the concentrations of 15 soy isoflavone species, including 3 succinyl glucosides, in 22 soy foods and isoflavone supplements by high-performance liquid chromatography (HPLC). The total isoflavone contents in 14 soy foods and 8 supplements ranged from 45 to 735 μg/g and from 1,304 to 90,224 μg/g, respectively. Higher amounts of succinyl glucosides were detected in natto, a typical fermented soy product in Japan; these ranged from 30 to 80 μg/g and comprised 4.1-10.9% of the total isoflavone content. In soy powder, 59 μg/g of succinyl glucosides were detected, equivalent to 4.6% of the total isoflavone content. These data suggest that the total isoflavone contents may be underestimated in the previous studies that have not included succinyl glucosides, especially for Bacillus subtilis -fermented soy food products.