The outer coating of the seeds Bixa orellana is the source of annatto color and its liquid extract usually contains (16E)-bixin, which is an isomer of the principal pigment, bixin (20-methyl ester of (2E, 4E, 6E, 8E, 10E, 12E, 14E, 16Z, 18E)-4,8,13,17-tetramethyl-2,4,6,8,10,12,14,16,18-icosanonaen-1,20-dioic acid). In order to clarify whether (16E)-bixn is natural or not, the outer coating seeds were extracted with supercritical fluid carbon dioxide and the extract adsorbed in a trap column was directly analyzed on ODS column chromatography using supercritical fluid carbon dioxide as eluent. In the chromatogram, (16E)-bixin was not observed and this strongly indicated that (16E)-bixin is not a naturally occurring compound.

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Sepia color is a black food color made from the ink sacks of cuttlefish, e.g. Sepia officinalis L. To establish specifications for sepia color, the methods for identifying and describing the pigment content as a color value were examined. These methods are based on eumelanin degradation by hydrogen peroxide. The amount of sample and the reaction time were optimized for identification. Sufficient reproducibility and linearity of the assay were obtained under a low concentration of hydrogen peroxide, which facilitates application to the determination of color value. The protein content of sepia color as the concentration of amino acid residues not directly bound to insoluble eumelanin was determined by hydrolysis with hydrogen chloride. The protein content was estimated to be about 10%.

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We analyzed the serum fatty acid of 30 asthmatic children at the age of 6 years and 60 healthy controls. The proportion of linolic acid and n-6/n-3 ratio of asthmatic children were greater than that of healthy controls. And the proportion of DHA and arachidonic acid were lower than controls. As for asthmatic children who were positive RAST testing for Dermatophagoides farinae (Df), the proportion of n-3 series fatty acid was lower than controls who were positive RAST testing for Df. In both asthmatic children and controls, n-6/n-3 ratio was negative correlated with n-3 series fatty acids. So, for reducing n-6/n-3 ratio, it might be most effective that more intake of n-3 series fatty acids was recommended. These results suggested that asthmatic children had different dietary life style from healthy controls, which was one of the main risk factor of asthmatic children as well as other environmental factors.

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Food additives have contributed to safe and stable supply of food. Although acceptable daily intake (ADI) has been used for the safety assessment of each food additive, their synergistic effcts on our health is unclear. Actually, several food additives are usually used together in a food, therefore, they may have some adverse effect on cellular levels and/or whole animals even if their individual used levels are below ADI, or commercially used levels. In this parer, we carried out to investigate their cellular effects as well as whole body effects in case of simultaneous use on ADI and daily intake level. Two commonly used preservatives (sodium benzoate and potassium sorbate) and four artificial red colors (Nos.3, 40, 102 and 106) certified by the Japanese Standard of Food Additives) were chosen and used. Each preservative was dissolved in Ca²⁺, Mg²⁺ free Tyrode buffer pH 7.4 at final concentrations corresponded to 1/10ADI and 1/40ADI, and each red colors was used at concentrations of 0.01% and 0.001%. Washed rabbit platelets were prepared by the method decribed. An aliquot (2×10⁷ platelets) was incubated with calcium ionophore A-23187 (10^-6M) or thrombin (1U), or without either agonist in the presence or absence of preservative and red coloring mixture. Commercially used amount of each preservative and color was added together to drinking water and administered to a rabbit for 5 days, then washed platelets were prepared and subjected to incubation. Incubation lasted for 5 min at 37℃ with vigorous shaking and was terminated by placing the reaction mixture on ice followed by centrifugation. The magnitude of platelet activation was determined by the amount of thromboxane B₂ (TXB₂) synthesis and the extent of platelet aggregation. Among several combinations of preservative and artificial red color, mixtures of sodium benzoate and red No.3 had inhibitory effect on both agonists' induced TXB₂ synthesis (Fig.1, 2) in vitro. On the other hand, mixtures of potassium sorbate and red colors revealed no effect on both agonists induced TXB₂ synthesis (Fig.3, 4). In an ex vivo experiment, only a weak inhibitory effect was observed at thrombin induced TXB₂ synthesis in combination of potassium sorbate and red No.106 (Fig.6B). There was not any significant effect on platelet aggregation (Fig.7-10) or blood biochemical assay data (Table 1, 2). These results indicate that it is important to consider an interactive effect of food additives used together when we make safety assessment of food additives.

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In this study, change of the total carotenoid contents and β-cryptoxanthin contents of Satsuma mandarin juice caused by heating, illumination and storage were examined. Carotenoid of Satsuma mandarin juice were extracted and saponified before quantitation. There was 16% reduction of total carotenoid and 21% reduction of β-cryptoxanthin of Satsuma mandarin juice, when exposed of heating at 95℃ for 10 minutes. There was 10% reduction of total carotenoid and 18% reduction of β-cryptoxanthin of Satsuma mandarin juice, when exposed of illumination at 600 W/m² for 80 hours. The cis isomers increased by heating were estimated as 15-, 13- and 13'-cis-β-cryptoxanthin. The cis isomers increased by illumination were estimated as 9- and 9'-cis-β-cryptoxanthin. In these results, it was shown that the cis isomers increased by heating were different from the cis isomers increased by illumination. Total carotenoid and β-cryptoxanthin contents of Satsuma mandarin juice were decreased by storage, and higher storage temperature brought on more reduction. Cis isomers increased by storage were same as that increased by heating.

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A thermophile producing high amounts of extracellular pectolytic enzyme was isolated from soil. The isolate (KP1280) that grew from 40 to 60 ℃ was identified as a strain of Thermomonospora fusca. Maximum production of the enzyme was achieved after 60 h of cultivation at 60℃ and at an initial pH of 7.5 on a medium containing 5.0% polygacturonic acid, 0.5% peptone, 0.1% yeast extract and 0.3% KH₂PO₄. The hydrolyzing activity towards polygalacturonic acid was most active at 80℃ in the presence of 6 mM CaCl₂. The enzyme was stable up to 75℃ when it was incubated at pH 6.8 for 30 min in the presence of 7.5 mM CaCl₂. The end produnt of the reaction contained a mixture of galacturonic acid and unsaturated oligogalactutonic acids. The application of this enzyme to the fruit juice industry is discussed.

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A combination of the extraction and hydrolyzation procedures with acidified aqueous methanol was proposed to analyse strophanthidin and digitoxigenin in Corchorus olitorius (Moroheiya) and its commercial products. Plant and product samples were refluxed in methanol-0.2 mol/LHCl (2+1) at 70℃ for 2 hrs, and then stood in methanol-1.0 mol/LHCl (2+1) at room temperature for 24 hrs. A solution of the hydrolysate from well-matured seeds was directly subjected to HPLC to determine strophanthidin and digitoxigenin. For the sample from immatured seeds, Sep-pak plus Silica cartridge was used to concentrate the genins in the hydrolysate before HPLC. Since the leaves, the stems, and the products contained large amounts of contaminants, the successive purification of the hydrolysate with GPC, Sep-pak plus Silica cartridge, and ENVI-Carb Packing tube was needed to apply HPLC. The determination limits of strophanthidin and digitoxigenin in well-matured seeds, immatured seeds and others were, 10μg/g, 1μg/g and 0.02μg/g, respectively. Recoveries from the leaves, the stems, and products spiked with the genins (each 2μg/g) were 72.2-73.0% for strophanthidin and 79.6-82.6% for digitoxigenin, respectively.

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When simple handmade yogurt was prepared using the mixture of Streptococcus thermophilus NB-1, Lactobacillus bulgaricus NB-15, Lactobacillus acidophilis NB-20 and Bifidobacterium longum NB-26 as a starter, selective media were needed for detecting the bacterial flora, and then developed. TSM agar was devised as a selective medium for S. thermophilus NB-1 by pH (8.0) arrangement of Tryptosoy agar; MSN-LBS agar for L. acidophilus NB-20 by the addition of NaN₃ to LBS agar in which glucose was replaced with maltose and sucrose; BSM agar for B. longum NB-26 by decreasing antibiotic amounts in BS agar. A selective medium of L. bulgaricus NB-15 was not devised, but the viable counts was enumerated by subtracting numbers of colonies on MSN-LBS agar from the ones on modified LBS agar. Tryptosoy agar, LBS agar and BL agar, a main compoment of BS agar are commercial media, while BS agar is well known as a medium for Bifidobacterium isolation from intestinal materials. The developed media were used for analysis of the flora in the handmade yogurt incubated at 37℃ for 6 hours. At the end of incubation the viable counts of S. thermophilus NB-1 and L. bulgaricus NB-15 increased up to 1000 times of those at 0 hours, with being 1.5×10⁹/ml and 6.5×10⁸/ml, respectively, while those of L. acidophilus NB-20 and B. longum NB-26 increased only 10 times, with being 5.6×10⁴/ml and 2.3×10⁶/ml, respectively.

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The method of simple and rapid determination of sodium azide in foods was examined by steam distillation-ion chromatography. The solid samples were distilled after homogenization under alkalinity. A samples (40g of liquid, 10g of solids) was added 4N H₂SO₄ and distilled under acid condition. The 15mL of the distillate were trapped into 5 mL of 10.8mM Na₂CO₃/1.2mM NaHCO₃ (or 50mM Na₂CO₃). The 50μL of distillate was injected into the ion chromatography system (Column: IonPacAS12A+IonPacAG12A, Eluent: 2.7mM Na₂CO₃/0.3mM NaHCO₃, Flow Rate: 1.5mL/min) to analyze. When 5 or 20μg/g of azide ions were added, the average recoveries of sodium azide in 33 kinds of food, such as beverages, shucks, and the vomit were 89.0-102.3% with low variation coefficients (0.7 to 7.9%). The detection limits were ranged 0.03-0.04μg/g for liquid samples, 0.1μg/g for solid samples and the vomit. It took 20 minutes for the liquid food and 25 minutes for the solid foods to analyze.

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Concentrations of five isoflavones, daidzin, glycitin, genistin, daidzein and genistein, in various soybean materials in soy process and soybean products (miso, natto and tempe) were determined by HPLC. Soybean and defatted soybean contained large amount of daidzin and genistin and the concentrations of their aglycone compounds, daidzein and genistein, in these materials were low. Isoflavone concentration of soybean husk was very low (below 0.01% dry weight). Although isoflavones were detected in various soybean fermented products such as miso, natto and tempe, but not in soy sauce. Soy sauce oil contained large amount of isoflavone aglycones (daidzein: 0.09 mg/ml and genistein: 0.47 mg/ml). Soy sauce oil as well as soy sauce lee would become a new good material for the supply of these important isoflavones.

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A survey of pesticide residues in 20 samples of health tea and 13 samples of herbal tea shown in table 1 was done. Ninety-seven kinds of pesticides, that is, 13 kinds of organochlorine, 12 kinds of pyrethroid, 31 kinds of organophosphorus, 13 kinds of carbamate (containing matabolites), 25 kinds of the other organonitrogen and 3 kinds of the other pesticides were surveyed (table 2). The results were shown as follows. 1) Thirteen kinds of insecticides, that is, β-BHC, δ-BHC, op'-DDT, pp'-DDT and pp'-DDE of organochlorine, DDVP, malathion, MEP, EPN and chlorpyriphos of organophosphorus, MIPC of carbamate, diflubenzuron and pyridaben of the other organonitrogen pesticides were detected in 15 out of the 33 samples of herbal tea and health tea (table 4). 2) Pesticide except for organochlorine was not detected in tea of flower and roast tea. Organochlorine pesticides was scarcely detected in roast tea (table 3). Chlorpyriphos, MEP and EPN of organophosphorus, diflubenzuron of the other organonitrogen pesticides were detected at high levels (table 4). 3) op'-DDT in addition to pp'-DDE of highly residual pesticides were detected in high frequency. And organochlorine pesticides were detected in all of health tea and herbal tea cultivated in China (table 4, fig.1). 4) Comparing with the criteria of pesticide residues for 'tea' based on the Food Sanitation Law, DDT, MEP, EPN and chlorpyriphos were detected at exceeded levels. Therefore, inspecting levels of these pesticides by extraction method with boiling water based on that law, detection levels of all pesticides were less than that criteria. However, MEP was detected at rather high levels of 50 % of the criterion. From the above-mentioned results, it will be necessary to make a more detailed survey of pesticide residues in health tea and herbal tea.

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