The deacetylation of peroxisome proliferator-activated receptor gamma coactivator-1alpha (PGC-1α) by the activation of mammalian sirtuins (SIRTs) promotes mitochondrial function and metabolic homeostasis. We previously demonstrated that alkylresorcinols (ARs) from rye wheat raised the Vmax of recombinant SIRT1 for NAD+ and extended the lifespan of the fruit fly Drosophila melanogaster. Olivetol (1,3-Dihydroxy-5-pentylbenzene), the smallest alkyl chain AR from lichen, also raised the Vmax of recombinant SIRT1. We hypothesized that the specific deacetylation of PGC-1α would: (i) be enhanced by increasing the rate of the enzyme-catalyzed reaction of SIRT1, and (ii) affect mitochondrial function and obesity-related metabolic disorders. We investigated the effect of ARs on obesity in mice fed a high-fat diet and in humans. The weight of the olivetol-high-fat diet (HFD) mice was significantly suppressed compared to the control-HFD group. The human subjects’ BMI was significantly lower in both the first and second halves of the 40-day test period compared to the placebo group. Compared to the control-HFD data, the amount of acetylated PGC-1α in the skeletal muscle of the olivetol-HFD mice was significantly decreased and the number of mitochondria in their brown adipose tissue (BAT) was significantly increased. In a supplementary experiment, the median lifespan of Drosophila melanogaster fed the olivetol-HFD was significantly extended by up to 113% in males and 109% in females versus that in the D. melanogaster fed a normal diet. The AR effects were thus associated with an induction of genes for lipid metabolism and were largely explained by PGC-1α deacetylation.

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This study determined the properties of Earl Grey Japanese black tea, called wakocha or jikocha in Japanese. Wakocha Earl Grey samples were as follows: “Aun” Earl Grey from Shimanto-cho in Kochi prefecture; “Ureshino” Earl Grey from Saga City in Saga prefecture; and “Sashima” Earl Grey from Sashima-gun in Ibaraki prefecture. We determined the content of essential oil and theaflavins in Earl Grey wakocha and the active oxygen-scavending function (SOD). We compared these results with those for nine other varieties of Earl Grey from around the world. The essential oil level of Aun which ranked second among the 12 tea samples, was around twice that of Ureshino and Sashima. The theaflavin content of the three Earl Grey wakocha samples ranked in the mid range of all tea samples. The caffeine level of all samples ranged from 2.10 to 2.98 mg per 100 g of tea leaf. The activity of SOD was higher in Aun than in Ureshino and Sashima. Enantiomer analysis of linalool was determined in order to verify the authenticity of the bergamot peel oil used to flavor the tea leaves. The purity of genuine bergamot oil was more than 99% enantiomeric excess of (R) (-)-linalool, the highest concentration, while the purity of (R)-(-)-linalool in other citrus oils was less than 96%ee; hence among the Earl Grey flavoring materials, it is possible to distinguish genuine bergamot oil from artificially blended bergamot oil. This analysis provided substantial evidence that the following Earl Grey varieties were flavored using genuine bergamot oil, Aun and Ureshino, and Sashima, Nittoh, Mariage. Wedgwood and Fortnum & Mason were also in this category.

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Olive leaf cold-water extract (OEx), which has cross-linking activity of protein molecules, modifies the physical properties of heat-induced chicken egg white gel. In this study, we investigated the effect of OEx in the range of 0.1 to 1.0% (w/w egg white) on the physical properties of egg white meringue. The overrun of meringue prepared from egg white decreased with increasing amount of OEx. For meringue baked at 121ºC, the specific volume of baked meringues with 0.1 and 0.5% OEx tended higher than that of OEx-free counterpart. Baked meringue with 0.5% OEx had 1.3 times higher breaking stress than that without OEx. On the other hand, for meringue baked at 93ºC, baked meringue with 0.5% OEx had 1.6 and 1.9 times higher breaking stress and breaking strain than OEx-free meringue, respectively. Scanning electron observation showed that the addition of 0.5% OEx to egg white induced denser microstructure of baked meringue. The contents of primary amino group and SH group in egg white protein decreased with increasing addition of OEx, contrarily the cross-linkage formation between protein molecules enhanced. It is presumed that the chemical changes, that is protein cross-linkage etc, link to the denser microstructure in baked meringue; resulting in the modification of the physical properties. The present study suggests that OEx is feasible to improve the texture of meringue-based confectioneries.

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As reported in previously, we established a sample preparation method for determining residual apramycin in livestock products by LC-MS/MS, where we utilized an external calibration method. In this study, the n-hexane–trichloroacetic acid (hexane–TCA) method by us was applied to the sample preparation method for LC-MS/MS analysis, and evaluated the linearity of the calibration curve and the validity of the quantitative value. Bovine tissue samples (e.g., muscle, fat, and liver) were extracted using the hexane– TCA method, and cleanup was performed using two different hydrophilic–lipophilic balance (HLB) cartridge columns and a MCX cartridge column for these samples. The apramycin in the resulting samples was quantified by LC-MS/MS by utilizing an external calibration curve. The validation study was performed on bovine tissues spiked with apramycin at maximum residue limits (MRLs; muscle and fat: 0.5 ppm; liver: 5 ppm) and a value equivalent to 1/10 of MRLs (1/10 MRLs; muscle and fat: 0.05 ppm, liver: 0.5 ppm). The trueness (n = 5) values of apramycin based on the used three kinds of bovine tissue were 84.3%–92.7% at MRLs and 79.2%–97.8% at 1/10 MRLs, and the relative standard deviations (RSD) were 2.1%–5.9% at MRLs and 2.8%–5.7% at 1/10 MRLs. The limit of quantification (LOQ) of the developed method were 0.05 mg/kg (0.05 ppm) for bovine muscle and fat and 0.5 mg/kg (0.5 ppm) for the bovine liver according to the results of the validation study.

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The applicability of HPLC to the official testing method for methyl methacrylate (MMA) in food utensils, containers and packaging made from poly (methyl methacrylate) was investigated. The HPLC conditions were determined according to Japanese Industrial Standards (JIS) as follows, the column: ODS column; the mobile phases: acetonitrile and water; and the detection wavelength: 205 nm. Furthermore, the gradient condition was optimized so that the MMA peak did not overlap with the peaks derived from the contaminant. Although the MMA standard solution was specified to be prepared in 20% ethanol (EtOH) in the official testing method, MMA seemed to be unstable in 20% EtOH. Therefore, the standard solution was prepared with EtOH. Furthermore, the obtained test solution was diluted more than 10-fold with EtOH, which made stable analysis of MMA. We validated the performance in terms of limit testing and quantitative testing methods. All parameters corresponding to the trueness, repeatability, and reproducibility as intermediate precision, satisfied the target values in both cases, indicating that this method demonstrates good performance as a testing method.

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Vitamin K and (-)-Epigallocatechin-3-gallate(EGCg) are components of tea leaves, and both are effective in maintenance of bone health. Vitamin K is hydrophobic, so is not contained in water-extracts. However, consumption of tea powder enables intake of both substances. In this study, in order to investigate the effects of tea powder consumption on bone health in postmenopausal females, experimental feeds were provided to postmenopausal-osteoporosis-model mice for 4 weeks, after which bone tissue parameters were measured by micro-CT. The findings were that bone mineral density decrease was suppressed in the group provided feed containing 0.03% (w/w) tea powder, and it was thought that the main effect ingredient in tea powder was vitamin K1. These findings suggest that tea powder intake may be effective for suppressing bone mineral density decrease in postmenopausal females.

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