Simultaneous Synthesis of Vitamins D, D, D, D, and D from Commercially Available Phytosterol, β-Sitosterol, and Identification of Each Vitamin D by HSQC NMR.

We succeeded in simultaneously synthesizing the vitamin D family, vitamins D, D, D, D, and D, from β-sitosterol, which is sold as a commercially available reagent from Tokyo Chemical Industry Co., Ltd. It is officially sold as a mixture of four phytosterols {β-sitosterol (40-45%), campesterol (20-30%), stigmasterol, and brassicasterol}.

Diversity in γ-oryzanol profiles of Japanese black-purple rice varieties.

The γ-oryzanol contents and the composition of steryl ferulates distributed in Japanese pigmented rice varieties were investigated using the high-performance liquid chromatography-ultraviolet detection method for the purpose of expanding their utilisation. The average γ-oryzanol content in nine black-purple, four red, four green and three brown rice varieties was 54.2, 47.

Synthesis of three deoxy-sophorose derivatives for evaluating the requirement of hydroxy groups at position 3 and/or 3' of sophorose by 1,2-β-oligoglucan phosphorylases.

Sophorose (Sop) is known as a powerful inducer of cellulases in Trichoderma reesei, and in recent years 1,2-β-D-oligoglucan phosphorylase (SOGP) has been found to use Sop in synthetic reactions. From the structure of the complex of SOGP with Sop, it was predicted that both the 3-hydroxy group at the reducing end glucose moiety of Sop and the 3'-hydroxy group at the non-reducing end glucose moiety of Sop were important for substrate recognition. In this study, three kinds of 3- and/or 3'-deoxy-Sop derivatives were synthesized to evaluate this mechanism.

Degradation of Fucoxanthin to Elucidate the Relationship between the Fucoxanthin Molecular Structure and Its Antiproliferative Effect on Caco-2 Cells.

Fucoxanthin has an antiproliferative effect on cancer cells, but its detailed structure⁻activity correlation has not yet been elucidated. To elucidate this correlation, fucoxanthin was degraded by ozonolysis. The degraded compounds of fucoxanthin obtained by ozonolysis were purified by HPLC and analyzed by NMR.

The content and distribution of steryl ferulates in wheat produced in Japan.

Oryzanol contained in rice bran is a complex mixture of steryl ferulates (SFs) with many identified health benefits. Recently, SF has been shown to exist in other cereals such as wheat, rye, and corn. In this study, SFs in several wheats produced in Japan were analyzed.

Inconsistencies in a highly polar capillary gas chromatography column and necessity of column performance checks for trans fatty acid measurement.

GC with a capillary column (60-100 m length) is widely used to measure trans fatty acids in dietary fats and biological tissues. Recently, we have occasionally observed that isothermal operation of an SP-2560 column at 180 degrees C results in incomplete separation of gondoic acid (11c-20:1) and one of the geometric isomers of alpha-linolenic acid (9t,12c,15c-18:3), although it has been known to produce their baseline separation in American Oil Chemists' Society Official Method Ce 1h-05, as well as in previous studies. Thus, trans isomer (9t,12c,15c-18:3) is one of the main components of trans fatty acids in refined edible oils, and the baseline separation of this peak from that of 11c-20:1 is indispensable.

cis-trans isomerization of carbon double bonds in monounsaturated triacylglycerols via generation of free radicals.

We investigated the heat-induced cis/trans isomerization of double bonds in monounsaturated lipids. When triolein (9-cis, 18:1) was heated around 180 degrees C, small amounts of isomerization products were obtained depending on the heating period. The heat-induced isomerization of triolein was considerably suppressed by the addition of different antioxidants or under nitrogen stream, and these additives simultaneously inhibited the thermal oxidation of double bonds in triolein.

Preparative separation of cis- and trans-isomers of unsaturated fatty acid methyl esters contained in edible oils by reversed-phase high-performance liquid chromatography.

In order to measure exactly the trans-fatty acids content in food materials, a preparative group separation of cis- and trans-isomers of unsaturated fatty acid methyl esters (FAMEs) was achieved by an isocratic reversed-phase HPLC (RP-HPLC) method. The trans-isomers of 16:1, 18:1, 18:2, 18:3, 20:1 and 22:1 FAMEs were readily separated from the corresponding cis-isomers by a COSMOSIL Cholester C18 column (4.6 mm I.

Absorption properties of micellar lipid metabolites into Caco2 cells.

To elucidate the absorption characteristics of dietary lipids in the human intestine, we investigated the cellular uptake of lipid metabolites using a differential monolayer of the Caco2 cells. As lipid metabolites, several free fatty acids and 2-monoacylglycerols, were formed a mixed micelle by bile salts and lysophospholipids and they were supplied to the Caco2 cells. To estimate the effect of the mixed micelles on the permeability of cells' membranes during incubation with the mixed micelles, the transepitherial electrical resistance (TEER) value was monitored, and no pronounced changes of TEER was detected.

Intestinal epithelial cells absorb gamma-tocotrienol faster than alpha-tocopherol.

To elucidate the transepithelial transport characteristics of lipophilic compounds, the cellular uptake of tocopherol and tocotrienol isomers were investigated in Caco2 cell monolayer models. These vitamin E isomers formed mixed micelles consisting of bile salts, lysophospholipids, free fatty acid, and 2-monoacylglycerols, then the micelles were supplied to Caco2 cells. The initial accumulation of tocotrienol isomers in Caco2 cells was larger than those of corresponding tocopherol isomers.

Acyl moieties modulate the effects of phospholipids on beta-carotene uptake by Caco-2 cells.

The intestinal absorption of carotenoids is thought to be mediated by the carotenoid assembly in mixed micelles, followed by its transfer into the enterocytes and subsequent secretion to the lymph as chylomicron particles. In the present study we investigated the effects of phospholipids and lysophospholipids with diverse fatty acyl moieties on the uptake of beta-carotene solubilized in mixed micelles by Caco-2 cells. Compared with phospholipid-free mixed micelles (NoPL), those containing long-chain PC inhibited beta-carotene uptake (16:0,18:1-PC approximately equal to 16:0,18:2-PC < 14:0,14:0-PC approximately equal to 16:0, 14:0-PC < 16:0,16:0-PC < NoPL).

Acidolysis between triolein and short-chain fatty acid by lipase in organic solvents.

Ten kinds of lipases were examined as biocatalysts for the incorporation of short-chain fatty acids (acetic, propionic, and butyric acids) into triolein in order to produce one kind of reduced-calorie structured lipids. Trans-esterification (acidolysis) was successfully done in n-hexane by several microbial lipases. Among them, lipase from Aspergillus oryzae was used to investigate the effects of incubation time, substrate molar ratio, and water content on acidolysis.

Inhibitory effect of lysophosphatidylcholine on pancreatic lipase-mediated hydrolysis in lipid emulsion.

In the lipid metabolism pathway, dietary lipid emulsified with bile salts and phospholipids is mainly digested by pancreatic lipase into free fatty acids and monoacylglycerols. In order to study substrate recognition mechanism of a pancreatic lipase, we investigated its catalytic property toward the lipid emulsion prepared with long- or intermediate-chain acylglycerols and several physiological surfactants. When lysophosphatidylcholine (LysoPC), rather than bile salts or phospholipid, was incorporated into the lipid emulsion, it caused an increase in the Km(app) and a decrease in the Vmax(app) values in the interactions between the lipase and triacylglycerol (triolein or tricaprin).

Polar organic solvent added to an aqueous solution changes hydrolytic property of lipase.

For developing further uses of lipase as a biocatalyst, its hydrolytic activity toward some esters was investigated in a miscible solution composed of a buffer and a polar organic solvent. Twenty percent dimethylformamide, 35% dimethylsulfoxide, 15% 1,4-dioxane, 15% dimethoxyethane, and 2% diethoxyethane promoted the hydrolysis by a lipase from Rhizomucor miehei toward some hydrophobic substrates, 4-methylumbelliferyl oleate, 4-methylumbelliferyl palmitate, and monoolein. While hydrolysis by this lipase toward the substrates with a relatively weak hydrophobicity (4-metylumbelliferyl heptanoate and 4-methylumbelliferyl nanoate) was suppressed by these solvents.

Fluorimetric analysis of lipase hydrolysis of intermediate- and long-chain glycerides.

For the purpose of deducing the digestive behavior of dietary fat in the digestive organs, a fluorimetric method for the measurement of hydrolysis by porcine pancreatic lipase was performed using intermediate- and long- acyl chain glycerides as substrates. Insoluble glycerides constituted by C10-C16 acyl chains were mechanically dispersed in 100% buffer and hydrolyzed by porcine pancreatic lipase. After the reaction, fatty acid released by the enzyme was extracted and its carboxyl group was fluorescently labeled with 9-bromomethylacridine.

Brown algae fucoxanthin is hydrolyzed to fucoxanthinol during absorption by Caco-2 human intestinal cells and mice.

The metabolic fate in mammals of dietary fucoxanthin, a major carotenoid in brown algae, is not known. We investigated the absorption and metabolism of fucoxanthin in differentiated Caco-2 human intestinal cells, a useful model for studying the absorption of dietary compounds by intestinal cells. Fucoxanthin was taken up by Caco-2 cells incubated with micellar fucoxanthin composed of 1 micromol/L fucoxanthin, 2 mmol/L sodium taurocholate, 100 micromol/L monoacylglycerol, 33.