Trans-fatty acids are a type of unsaturated fatty acid in which the double bonds have a trans structure, as opposed to the cis structure often found in nature. Natural types of trans-fatty acids are produced in the first stomach (rumen) of ruminant animals and are known to accumulate in the milk and meat of these animals. A large-scale epidemiological survey in Europe and the U.S.A. has suggested that excessive intake of trans-fatty acids increases the risk of coronary heart disease. We have performed a comprehensive study of the amount of trans-fatty acids present in meat circulating throughout Japan to assess the current amounts of trans-fatty acids. The results reveal that the amount of trans-fatty acids in the type of beef (lean and fat) regularly consumed in Japan ranges from 0.33 to 1.87 g per 100 g. In addition, in beef fat, the amount of trans-fatty acids ranges from 1.43 to 9.83 g per 100 g. Among offal, rumen showed 1.70 g/100 g, the highest level. The results of this study indicate that, even between the same cuts, trans-fatty acid levels vary depending on the type of feed and duration of the grain-feeding period. In addition, in a study of pork and chicken, the amount of trans-fatty acids did not exceed 0.3 g/100 g in any part of the animal.

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In the course of our evaluation of the quality of crude drugs, we examined the conditions under which ginger is processed. In an examination of the relationship between the drying conditions after harvest and inhibitory activity toward nitric oxide (NO) production, we found that drying at a higher temperature gave greater inhibitory activity than drying at a lower temperature. In addition, five constituents were isolated from ginger extract, and their inhibitory activities toward NO production were investigated. Among them, shogaol analogues showed the strongest inhibitory activity.

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A method has been developed for determining amygdalin (AM) and its degradation products, benzyl alcohol (BeOH), benzaldehyde (BAL) and benzoic acid (BA) in Chinese quince fruit utilizing high performance liquid chromatography (HPLC). A sample was extracted with 0.05 mol/L citric acid solution (pH2.2) and cleaned in an InertSep C18 cartridge and an InertSep NH₂ cartridge. The HPLC separation was performed on an Inertsil ODS-4 column using acetonitrile-0.01 mol/L phosphate buffer (pH2.0) (15:85) in the mobile phase. A UV monitor was used for detection. The effects during growth period on the amount of 4 components of sarcocarp and seed of Chinese quince was examined. AM content in seed increased proportionally each month. This increase was especially significant in seed retrieved in November. AM was detected in commercially available Chinese quince in the range of 0.03-0.06 mg/g sarcocarp, 0.21-1.75 mg/g seed. BA was not detected in any samples.

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We performed the comparative study on changes of cytochemical Mg²⁺-adenosine triphosphatase (Mg²⁺-ATPase) activity and its localization caused by a decrease in freshness of white (W), pink (P), and red (R) muscles in cultured carp during storage in ice. The contents of ATP-related compounds in the three muscle types were higher in the order of R>P>W, and the increasing of K value was faster in the order of R>P>W. Mg²⁺-ATPase activity was found on the A band of myofibril, sarcoplasmic reticulum and mitochondria menbrane/crista in each muscle type at just after killing. The deactivation of Mg²⁺-ATPase activity in these organella was faster in the order of R>P>W during storage period. The interposition of pink muscle fibers into the dorsal ordinary muscle might accelerate the deterioration of fish mucle in post-mortem.

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An LC-MS/MS method for the simultaneous determination of pesticide residues in tea was developed by modifying the Japanese official multiresidue method. In the optimal sample preparation procedure, the following sequence of steps was adopted: (1) swelling of the sample in water; (2) extraction with acetonitrile; (3) removal of water by salting-out; (4) cleanup on an ODS column and then on a tandem graphitized carbon/PSA column. The resulting test solution was subjected to LC-MS/MS and determined by external solvent standard calibration. The recoveries for 135 pesticides from fortified green tea, black tea, oolong tea, and matcha (powdered green tea) after spiking at the Japanese maximum residue limits were mostly within the range 70-120%, with relative standard deviations of <20%. The test solutions obtained by the modified method were cleaner than those obtained by the original multiresidue method and contained relatively smaller amounts of pigments and other matrix components. No interfering peak was observed in the blank chromatograms, indicating the high selectivity of the modified method. Therefore, the developed method is considered to be highly efficient and suitable for the quantitative analysis of pesticide residues in tea.

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Asiasari Radix [roots and rhizomes of Asiasarum sieboldii F. Maekawa and Asiasarum heterotropoides F. Maekawa var. mandshuricum F. Maekawa (Aristolochiaceae)] is a traditional medicine. Sesamin and asarinin are important components of Asiasari Radix, and it is reported that their stereochemistry is l-form. On the contrary, the stereochemistry of sesamin and episesamin from sesame are reported as d-form. Therefore, we established a method for analyzing lignans with HPLC-chiral column to invesitigate precise stereochemistry of them from Asiasari Radix and sesame. As a result, we clarified that asarinin from Asiasari Radix existed as only l-form, and sesamin and episesamin from sesame existed as only d-form. In addition, we found that sesamin from Asiasari Radix was a mixture of 96〜95% l-form and 4〜5% d-form.

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Based on the traditional use of the calyx of eggplants for treatment of common warts and a clinical report that the ethanol extract of the calyx of the eggplant is effective for curing genital warts, the cytotoxicity of the ethanol extract of the eggplant against various cell lines established from human cancer cells was examined. The extract of eggplants inhibited cell growth of human ovary cancer (HRA) cells, which are of epithelial cell origin similar to common warts. The cytotoxicity of the extract from the calyx of the eggplants is much higher than that of the extract from the edible part of the eggplants. Two compounds, 9-oxo-(10E, 12Z)-octadecadienoic acid (9-EZ-KODE) and 9-oxo-(10E, 12E) octadecadienoic acid (9-EE-KODE) were isolated as cytotoxic constituents from the calyx of the eggplants. 9-EE-KODE exhibited approximately 10-fold higher cytotoxicity than 9-EZ-KODE. Furthermore, 9-EE-KODE revealed 5-fold more potent cytotoxicity against HRA cells than against other cell lines examined. The calyx contained higher levels of 9-EE-KODE than the edible part of the eggplants.

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Plasmids containing polymerase chain reaction (PCR) target sequences are widely used as positive controls for analyses of genetically modified food. To eliminate amplification of false positives due to plasmid contamination, we developed a qualitative PCR control plasmid containing amplicons with an additional internal restriction enzyme recognition site. We designed a control plasmid template having target sequence with additional BamHI site for detecting genetically modified rice line Shanyou 63 (Bt63). The target amplicons derived from the designed plasmid were completely digested by BamHI, whereas amplicons derived from the unaltered Bt63 genomic DNA template could not be digested. Thus, our control plasmid enables distinction between detection of false positives (caused by amplicons derived from the plasmid) and true positives (due to the presence of Bt63 rice genomic DNA) in qualitative PCR testing of genetically modified rice products.

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The leaf of Perilla frutescens var. frutescens (perilla leaf) contains rosmarinic acid and α-linoleinic acid; these compounds have antioxidative properties and reduce the risk of cardiovascular diseases. However, the beneficial effects of perilla leaf on metabolic syndrome have not been explored. In this study, we investigated whether perilla leaf powder, dried by microwave under reduced pressure, can reduce the risk of metabolic syndrome using SHR.Cg-Lepr^cp/NDmer (SHR-cp), a rat model of metabolic syndrome. The SHR-cp rats were divided into 3 groups: (1) the control group, which was given only sterile distilled water only, (2) the MH group, which was given 5 g/kg body weight/day of perilla leaf powder, (3) the ML group, which was given 1 g/kg body weight/day of perilla leaf powder. Perilla leaf powder was dissolved in sterile distilled water for administration. Body weight and food intake were measured every week and blood pressure was determined every 2 weeks. After 14 weeks of perilla leaf powder administration, rat plasma was collected and subjected to biochemical analysis, and fatty acid compositions and lipid peroxide levels were measured. Body weight and food intake were not significantly different among the groups. The changes in blood pressure from baseline to week 14 decreased significantly in the MH group compared with the other groups. Plasma triglyceride and total cholesterol levels also decreased significantly in the MH group compared with the levels in the other groups. Plasma levels of α-linoleinic acid, docosapentaenoic acid, and total n-3 fatty acids increased significantly in the MH group compared with the levels in the other groups. Lipid peroxide (LPO) levels in plasma were also decreased significantly in the MH group. Regression analysis revealed a significant positive correlation between plasma LPO levels and changes in the mean blood pressure and diastolic blood pressure from baseline to week 14 and a significant negative correlation between plasma LPO and α-linolenic acid levels and between plasma α-linolenic acid and plasma triglyceride levels. These results suggest that the administration of the perilla leaf powder, dried by microwave under reduced pressure, can potentiate anti-oxidative, anti-hypertensive, and antihyperlipidemic effects, leading to preventive effects on cardiovascular diseases.

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"Koshikon" (the roots of Lithospermum erythrorhizon) and "Nanshikon" (the roots of Arnebia euchroma) have been used as natural dye and medicine. Interestingly, shikonins, the components of those species, exist as mixture of enantiomers. In this report, we isolated six shikonins from "Koshikon", and five shikonins from "Nanshikon", and determined the enantiomer ratios of them by chiral-HPLC analysis. From the "Koshikon", acetylshikonin and β-hydroxyisovalerylshikonin were obtained with the low R/S ratio (74/26 and 90/10), while isobutyrylshikonin, β,β-dimethylacrylshikonin, α-methyl-n-butyrylshikonin and isovalerylshikonin were obtained as almost pure R-form (>95%). On the other hand, the "Nanshikon" gave acetylshikonin with the low R/S ratio (34/64), and isobutyrylshikonin, β,β-dimethylacrylshikonin, α-methyl-n-butyrylshikonin and isovalerylshikonin as almost pure S-form (just about 100%). Generally, enantiopure shikonins have been obtained by hydrolysis of shikonin derivatives followed by several recrystallizations. We established an easy and efficient method for preparing enantiomerically pure (R)-shikonin and (S)-shikonin by removing low-enanntiopure acetylshikonin and β-hydroxyisovalerylshikonin from shikonins before the hydrolysis.

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As a method for nutrition labeling, the quantitative analysis of molybdenum in food by inductively coupled plasma mass spectrometry after dry ashing at 500℃ was studied and validated. Single laboratory validation has been performed to evaluate the trueness, precision, applicability, limit of detection, limit of quantification and linearity of the method. Repeatability and intermediate precision of the method for analysis of molybdenum content in certified reference material (NIST SRM 3280, multivitamin/multielement tablets) were 3.8 and 3.8% relative standard deviation, respectively, with HorRat value 0.5. Recovery tests of molybdenum contents were performed 18 food samples. Consequently, the recovery rate of molybdenum ranged from 71 to 123% indicating the high applicability of the method.

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