Localization analysis of essential oils in perilla herb (Perilla frutescens var. crispa) using derivatized mass spectrometry imaging.

The localization of essential oils, including flavor components, in perilla herb (Perilla frutescens var. crispa) were visually determined using matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS) imaging. The surface of a perilla leaf was peeled using a cyanoacrylate adhesion compound and contained oil glands that retained their morphology and chemical properties. We imaged the three essential oils perillaldehyde, ß-caryophyllene, and rosmarinic acid (RA). Perillaldehyde was derivatized using glycine to prevent evaporation and allow its detection and imaging while localized in oil glands. ß-caryophyllene also localized in the oil glands and not in the epidermis region. RA was detected throughout the leaf, including the oil glands. Quantitative data for the three essential oils were obtained by gas chromatography- or liquid chromatography-MS. The concentrations of perillaldehyde, ß-caryophyllene, and RA were 12.6 ± 0.62, 0.27 ± 0.02, and 0.16 ± 0.02 [mg/g] in the paste sample of perilla herb. Peeling using a cyanoacrylate adhesion compound, and derivatization of a target such as an aroma component have great potential for mass spectrometry imaging for multiple essential oils.

Localization Analysis of Multiple Vitamins in Dried Persimmon (Diospyros kaki) Using Matrix-assisted Laser Desorption/ionization Mass Spectrometry Imaging.

The drying process used for persimmon fruit (Diospyros kaki) can alter the composition of nutrients, and especially vitamins. We visually determined whether the amounts of vitamin A1, vitamin B6 and vitamin C vary after drying persimmon fruit, using matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS) imaging. Drying altered the amount of moisture between the fruit interior and surface. Vitamin A1 is lipophilic and localized at the desiccated outer regions (pericarp) and not in the inner region (mesocarp and endocarp), and its concentration was increased 3.4 times in dried fruit compared with raw persimmon. Vitamin B1 and B6 are water-soluble and concentrated in the moist mesocarp. The vitamin C content of dried persimmon is decreased by drying in the sun. The drying process affected the localizations and amounts of all the vitamins. The observed opposite localization of vitamin A1 compared to B1 and B6 was due to vitamin A1 being lipophilic and B1 and B6 being water soluble. Multiplevitamin imaging using MALDI-MSI has great potential for enhancing commodity value and for visually investigating the effects of manufacturing processes.

Stimuli-responsive hydrogel-silver nanoparticles composite for development of localized surface plasmon resonance-based optical biosensor.

In this paper, the development of a localized surface plasmon resonance (LSPR)-based optical enzyme biosensor using stimuli-responsive hydrogel-silver nanoparticles composite is described. This optical enzyme biosensor was constructed by immobilizing glucose oxidase (GOx) into the stimuli-responsive hydrogel. When a sample solution such as glucose was applied to the surface of this optical enzyme biosensor, the interparticle distances of the silver nanoparticles present in the stimuli-responsive hydrogel were increased, and thus the absorbance strength of the LSPR was decreased. Furthermore, hydrogen peroxide, which was produced by the enzymatic reaction, induced the degradation of highly clustered silver nanoparticles by the decomposition of hydrogen peroxide. Hence, a drastic LSPR absorbance change, which depends on the glucose concentrations, could be observed. On the basis of the abovementioned mechanism, the characterization of the LSPR-based optical enzyme biosensor was carried out. It was found that the LSPR-based optical enzyme biosensor could be used to specifically determine glucose concentrations. Furthermore, the detection limit of this biosensor was 10 pM. Therefore, this LSPR-based optical enzyme biosensor has the potential to be applied in cost-effective, highly simplified, and highly sensitive test kits for medical applications.

Estimation of maturity of compost from food wastes and agro-residues by multiple regression analysis.

The composting process of food wastes and tree cuttings was examined on four composting types composed from two kinds of systems and added mixture of microorganisms. The time courses of 32 parameters in each composting type were observed. The efficient composting system was found to be the static aerated reactor system in comparison with the turning pile one. Using the multiple regression analysis of all the data (159 samples) obtained from this study, some parameters were selected to predict the germination index (GI) value, which was adopted as a marker of compost maturity. For example, using the regression model generated from pH, NH(4)(+) concentration, acid phosphatase activity, and esterase activity of water extracts of the compost, GI value was expressed by the multi-linear regression equation (p<0.0001). High correlations between the measured GI value and the predicted one were made in each type of compost. As a result of these observations, the compost maturity might be predicted by only sensing of the water extract at the composting site without any requirements for a large-size equipment and skill, and this prediction system could contribute to the production of a stable compost in wide-spread use for the recycling market.

Effects of bis(2-ethylhexyl) phthalate and benzo[a]pyrene on the embryos of Japanese medaka (Oryzias latipes).

Effects of two widely found chemical pollutants, bis(2-ethylhexyl) phthalate (DEHP) and benzo[a]pyrene (BaP), on the embryos of Japanese medaka were investigated. The embryos were exposed to different concentrations (0.01, 0.1, 1, and 10µg/l) of DEHP and BaP. The following were investigated: (1) hatching time and hatching rate in embryos, (2) mortality, sex ratio, body weight and gonadosomatic index (GSI) in adulthood. These two chemicals delayed the hatching time without dose-dependence, but these chemicals had no effect on hatching rate. Mortality was raised and body weight was reduced by DEHP and BaP-treatment; distortion of sex ratio appeared at the lowest concentration of DEHP tested. GSI was decreased because of the BaP-treatment. DEHP and BaP negatively affected Japanease medaka embryos, and the influences of the effects continued into adult stage. Moreover, the effects did not appear to be necessarily dose-dependent.

Effects of tamoxifen, 17α-ethynylestradiol, flutamide, and methyltestosterone on plasma vitellogenin levels of male and female Japanese medaka (Oryzias latipes).

The effects of oral administration of tamoxifen, 17α-ethynylestradiol (EE2), flutamide, and methyltestosterone (MT), on plasma vitellogenin levels of male and female medaka were investigated. Medaka were fed diets containing different concentrations of these chemicals for 7 days, and these plasma vitellogenin levels were measured. Tamoxifen increased significantly the vitellogenin levels in male, but inhibited the normal vitellogenin induction in female in the high concentration groups. EE2 increased significantly vitellogenin levels in both sexes. Flutamide increased significantly the vitellogenin levels in female, but gave no effects on male. MT inhibited the normal vitellogenin induction in female, but increased slightly vitellogenin levels in male without a clear tendency. Administration of tamoxifen, EE2, flutamide, and MT showed the different pattern in vitellogenin levels in both sexes.

Effects of bis(2-ethylhexyl) phthalate, γ-hexachlorocyclohexane, and 17ß-estradiol on the fry stage of medaka (Oryzias latipes).

The effects of bis(2-ethylhexyl) phthalate (DEHP), γ-hexachlorocyclohexane (γ-HCH), and 17ß-estradiol (E2) on the fry stage of medaka were investigated. The medaka fry were exposed to different concentrations (0.01, 0.1, 1, and 10µg/L) of these chemicals for 3 weeks after hatching. Then, mortality, body weight, sex ratio, and gonadosomatic index (GSI) of the matured fish (after 5 months) were measured. Mortality was increased significantly in the 10µg/L E2 group. Distortion of sex ratio was found in 1 and 10µg/L E2 groups. DEHP treated groups showed the GSI reduction only in male fish. All the γ-HCH and parts of the E2 treated groups showed the GSI reduction in both sexes. Exposure of DEHP, γ-HCH, and E2 during the fry stage affected normal maturation of medaka at the concentrations which had no impact on mortality or sex ratio.

Effect of alkylphenols on adult male medaka: plasma vitellogenin goes up to the level of estrous female.

The effect that oral administration of four alkylphenols, (1) bisphenol A (BPA), (2) p-t-octylphenol (OP), (3) p-nonylphenol (NP) and (4) p-n-nonylphenol (n-NP), as well as 17α-ethynylestradiol (EE2) had on male medaka fish vitellogenin was investigated. The male medaka was fed diets containing different concentrations of these chemicals for 7 days, after which their plasma vitellogenin levels were measured. Vitellogenin levels up to ≈10(7) ng/ml were found. This value is close to that of the normal estrous female medaka. The median effective concentration (EC(50)) values resulting from BPA, OP, NP and EE2 in the diet were calculated as 1600, 2600, 940 and 0.37 µg/g diet, respectively.