Keita Yunoki

Effect of dietary wine pomace extract and oleanolic acid on plasma lipids in rats fed high-fat diet and its DNA microarray analysis.

The aim of this study was to evaluate the concentration of oleanolic acids (OA) in pomace, a winemaking byproduct, and its influence on the levels of plasma lipids in rats fed a high-fat diet and on hepatic gene expression using DNA microarray analysis in vivo. HPLC analyses of pomace ethanol extract (PEE) revealed a high amount of OA ranging from 4 to 11 g/100 g. Male Sprague-Dawley rats were fed a normal-fat diet (NF group), a high-fat diet with 21% lard (HF group), a high-fat diet with 0.05% OA (OA group, 50 mg/kg/day), or a high-fat diet with 0.45% PEE (PEE group, 450 mg/kg/day). Plasma triacylglycerol and phospholipid concentrations were significantly lower in the OA and PEE groups than in the HF group. The microarray analysis of hepatic mRNA revealed reduced expression levels of lipogenic genes including acetyl-CoA carboxylase and glycerol-3-phosphate acyltransferase, probably resulting from the suppression of transcription factor Srebf1 expression. Gene expression of gluconeogensis and inflammatory cytokines was also down-regulated in the OA and PEE groups, suggesting that administration of OA or PEE could ameliorate obesity-induced insulin resistance, as well as prevent hyperlipidemia.

Analysis of sphingolipid classes and their contents in meals.

Sphingolipids have attracted attention as physiologically functional lipids. We determined their class and content in Japanese meals that had been prepared by a nutritionist, mainly by using HPLC-ELSD. In all 12 meals tested, cerebroside and/or sphingomyelin were generally detected as the major sphingolipids. The total amounts of sphingolipids in typical high- and low-calorie meal samples over 2 days were 292 and 128 mg/day, and 81 and 45 mg/day, respectively.

Simultaneous preparation of purified plasmalogens and sphingomyelin in human erythrocytes with phospholipase A1 from Aspergillus orizae.

A method for the simultaneous purification of plasmalogens and sphingomyelin (SM) in human erythrocytes is described. Treatment of total lipids with n-hexane/acetone (1:1 v/v) resulted in selective precipitation of SM. Both the supernatant and the precipitate fractions were incubated with a phospholipase A1 (PLA1) from Aspergillus orizae for 3.5 h. The PLA1-treated lipids were extracted with n-hexane/isopropanol, the hexane layer was obtained using a Na2SO4 solution, and the hexane layer was further washed with water. At this step, the relative concentration of the plasmalogens was 92% of the total phospholipids in the supernatant fraction, and that of SM was 97.7% in the precipitate fraction. Each fraction was applied to high performance liquid chromatography (HPLC) for further purification. The plasmalogen and SM obtained were almost free of the other lipids. The purity of the plasmalogens and SM was monitored by HPLC, which can separate intact plasmalogens from their diacyl analogs.

Screening for beneficial effects of oral intake of sweet corn by DNA microarray analysis.

To identify novel functions of the oral intake of sweet corn, we performed DNA microarray analysis of the livers of sweet corn-fed mice. Functional annotation clustering 1600 genes with expression levels that were affected (more than 1.5-fold change) by dietary sweet corn indicated that both cell proliferation and programmed cell death were modulated by sweet corn intake. In the Wnt signaling pathway, which is involved in cell proliferation, the levels of Jun and beta-catenin expression were downregulated by dietary sweet corn. The mRNA levels of Rb and p53, negative regulators of the cell cycle, were increased in mice fed with sweet corn. Dietary corn upregulated expression levels of genes that regulate apoptosis positively (for example, BOK, BID, CASP4). These results suggested that sweet corn is a valuable food for suppressing cancer. Oral administration of sweet corn inhibited tumor growth (36.6% reduce in tumor weight, P < 0.05) in mice inoculated with Ehrlich tumor cells.

Prominent Differences in Leaf Fatty Acid Composition in the F1 Hybrid Compared with Parent Trees Larix gmelinii var. japonica and L. kaempferi

Fatty acid (FA) compositions in leaves were investigated for two families of F1 hybrids of Larix gmelinii var. japonica × L. kaempferi (F1) and their parent clones. Twenty-one FAs, from C12 to C32, were found in the leaves of both adult trees and seedlings. The levels of 18:1/(18:2 + 18:3) increased in the order L. kaempferi, F1, and L. gmelinii var. japonica, with significant differences between L. gmelinii var. japonica and F1 in adult trees, but these differences were not found in the seedlings. Moreover, in the adult trees, the 18:1/(18:2 + 18:3) levels in the neutral phospholipid fraction and the ΣC18/ΣC16, especially in the glycolipid fraction, showed significant differences among the three species. These characteristics are discussed from the viewpoint of lipid synthesis in the endoplasmic reticulum and chloroplasts, and of the activities and substrate specificities in sequential FA desaturation. Linear discriminant analysis suggested that the FA compositions are useable as an index in the identification of hybrid seedlings.

Ethyl Esterification of Long-Chain Unsaturated Fatty Acids Derived from Grape Must by Yeast during Alcoholic Fermentation

The composition of total fatty acid ethyl ester (FAEE) in yeast cells and the liquid phase separated from grape must during alcoholic fermentation at different temperatures was investigated by using the solid-phase extraction method. Thirteen FAEE from butyric to linolenic acids were detected during fermentation. Significant amounts of long-chain unsaturated FAEE, including linoleic and linolenic acids derived from grape material, had already accumulated in the yeast cells by day 3 during fermentation.

Comparative analysis of diterpene composition in the bark of the hybrid larch F1, Larix gmelinii var. japonica × L. kaempferi and their parent trees

The diterpene compositions in the bark of branches were investigated for two families of the F1 hybrid, Kurile larch (Larix gmelinii var. japonica Pilg.) × Japanese larch [Larix kaempferi (Lamb.) Carr.] (hereafter F1) and their parents clones. 13-Epimanool, larixol, larixyl acetate, 13-epitorulosyl acetate (not detected in L. gmelinii var. japonica), isopimaric acid, abietic acid, dehydroabietic acid, and neoabietic acid were detected. Larixol and abietic acid represented more than 50% of the diterpene content in L. gmelinii var. japonica and L. kaempferi, respectively. Larixol and abietic acid were the predominant diterpene components in the F1, and the proportions of these diterpenes were between those of the parental species. Therefore, the diterpene compositions in the F1 were hereditarily infl uenced by their parents. The ratios of labdane, pimarane, and abietane diterpenes suggested that the main diterpene biosynthesis pathway in L. gmelinii var. japonica was from copalyl diphosphate (CDP) to labdane-type diterpenes, and that in L. kaempferi was from CDP to abietane-type diterpenes via pimarane type. Furthermore, linear discriminant analysis suggested that the diterpene contents are effective indices for the discrimination of the hybrid seedlings.

Chemical Properties of Epidermal Lipids, Especially Sphingolipids, of the Antarctic Minke Whale

It is well known that sphingolipids specifically exist in the terrestrial mammal epidermis and correlate with skin barrier functions. However, the lipid properties of the marine mammal epidermis have not been examined in detail. We thus investigated the chemical composition of lipid components, especially sphingolipids, in the black epidermis (outer skin) of Antarctic minke whales (six mature and six immature specimens). Complex lipid fractions mainly contained cerebroside (CE), cholesteryl sulfate and sphingomyelin (SM), as well as two glycerophospholipids. Moreover, in the superficial layer of the black epidermis, CE was richly abundant but phospholipids were scarce. As component fatty acids, the non-hydroxy monounsaturated very long chain fatty acids (VLFA) within 34 carbons were generally present in CE and SM in the black epidermis. CE also consisted of α-hydroxy fatty acids with monounsaturation within C34 (17%) and a slight proportion of ω-hydroxy ones (32:1 and 34:1), the latter being probably derived from acyl-CE. Component sphingoid bases of both sphingolipids were predominantly 4-sphingenine (64%), followed by a C16 analogue (21%). When comparing these by different maturities, mature whales showed sphingolipid profiles with higher levels of unsaturated fatty acids and with shorter sphingoid base chains than those of immature ones. Component analysis revealed that CE sugars were 67% glucose and 33% galactose, and α-hydroxy fatty acids only bound to galactose.

Content and fatty acid composition of sulfoquinovosyldiacylglycerol in conifer leaves grown in Hokkaido, Japan.

Sulfoquinovosyldiacylglycerol (SQDG) contents in conifer leaves and their fatty acid (FA) compositions were determined. The SQDG content was 16–36 mg/100 g, and was high in Picea glehnii. Palmitic and α-linolenic acid were the usually predominant FAs. In Picea, the proportion of α-linolenic acid was low, and those of oleic and linoleic acid were high. The essential oil residues of Abies sachalinensis leaves were found to be a potential source of SQDG material.