Solid-liquid phase behavior of binary fatty acid mixtures. 1. Oleic acid/stearic acid and oleic acid/behenic acid mixtures

Solid-liquid phase behavior of binary fatty acid mixtures was investigated by means of differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FT-IR) for the mixture composed of oleic acid (OA) and stearic acid (SA) and that composed of OA and behenic acid (BA). The DSC results provided a monotectic type T-X phase diagram for these mixtures, from which it was suggested that the two fatty acid species are completely immiscible in a solid phase regardless of the two polymorphs of OA, i.e., alpha-form or gamma-form. The solid phase immiscibility was confirmed by the FT-IR observation that the spectra obtained for the mixtures correspond to the superposition of the two spectra for respective components. Thermodynamic analysis of liquidus line demonstrated that OA and SA form an ideal mixture in a liquid phase, whereas the mixing of OA and BA in a liquid phase is slightly non-ideal.     

Absorption and metabolism of delphinidin 3-O-beta-D-glucopyranoside in rats

The absorption and metabolism of delphinidin 3-O-beta-d-glucopyranoside (Dp3G), which is the most potent antioxidant among the blueberry anthocyanins, were studied in rats. Dp3G rapidly appeared in the blood plasma within 15 min of oral administration (100 mg/kg body wt). The plasma level of absorbed Dp3G showed two peaks at 15 and 60 min after ingestion and then decreased time-dependently. However, the plasma level was maintained at approximately 30 nmol/l even after 4 h. Besides the Dp3G peak, a single major metabolite peak was detected by HPLC in the blood plasma obtained at 15 min. MS and NMR spectroscopy clarified that the chemical structure of the metabolite was 4'-O-methyl delphinidin 3-O-beta-d-glucopyranoside (methylation of the 4'-OH on the delphinidin B-ring). The present finding of this unique metabolite in anthocyanin metabolism strongly suggests that methylation of the 4'-OH on the flavonoid B-ring is a common metabolic pathway for flavonoids that carry the pyrogallol structure on the B-ring, as the same type of metabolite has been reported for other flavonoids such as epigallocatechin, but not for flavonoids carrying the catechol structure.     

Expression and purification of the Bacillus subtilis thioredoxin superfamily protein YkvV

Bacillus subtilis YkvV protein, an extracellular thioredoxin superfamily protein, was successfully expressed both in Brevibacillus choshinensis culture medium using an efficient promoter and the secretion signal of its surface layer protein, and in Escherichia coli cytoplasm with the amino-terminal His-tag (His-YkvV). His-YkvV was purified to homogeneity by Ni-NTA column. Both secreted YkvV and purified His-YkvV exhibited thiol-disulfide oxidoreductase activity.     

Oxysterol regulation of estrogen receptor alpha-mediated gene expression in a transcriptional activation assay system using HeLa cells

In order to test the estrogenic activity of sterol oxidation products from cholesterol and phytosterols, an estrogen-dependent gene expression assay was performed in estrogen receptor alpha-stably transformed HeLa cells. The ranking of the estrogenic potency of these compounds was different: 17beta-estradiol > genistein > beta-epoxycholesterol = daidzein = cholestanetriol = 22(R)-hydroxycholesterol = 20(S)-hydroxycholesterol = sitostanetriol > campestanetriol = beta-epoxysitosterol = 7beta-hydroxycholesterol. These compounds were not estrogenic in estrogen receptor-negative HeLa cells.     

Fatty acid compositions of commercial red wines

A determination was made of fatty acid compositions in twelve commercial red wines made from grapes differing in kind and vintage. Twelve fatty acids were identified, palmitic, myristic, and lauric acids being found predominant. Total acyls (32 approximately 81 nmol/100 ml) differed considerably. Changes in fatty acid constituents in must from grape berries and wines according to the process of manufacture were also examined.     

Presence of higher alcohols as ferulates in potato pulp and its radical-scavenging activity

Higher alcohols with a carbon length ranging from 16 to 30 found in the lipophilic fraction from potato pulp were shown to be present as ferulate and in a free form, but not as wax. Thin-layer chromatography of the neutral lipids in potato pulp indicated a few spots with scavenging activity toward the 1,1-diphenyl-2-picrylhydrazyl (DPPH) stable radical, the major active component being characterized as alkyl ferulate which showed almost the same level of activity as gamma-oryzanol.     

Identification and characterization of a new pair of immunoglobulin-like receptors LMIR1 and 2 derived from murine bone marrow-derived mast cells

We have identified and characterized two mouse cDNAs in a mouse antigen-stimulated bone marrow-derived mast cell cDNA library, both of which encode type I transmembrane proteins. The genes were closely mapped in the distal region of mouse chromosome 11 and expressed not only in mast cells but also widely in leukocytes. The extracellular domains of their encoded proteins contain a single variable immunoglobulin (Ig) motif sharing about 90% identity with amino acids, showing that they comprise a pair of molecules and belong to the Ig superfamily. We named these molecules leukocyte mono-Ig-like receptor1 and 2 (LMIR1 and 2). The intracellular domain of LMIR1 contains several immunoreceptor tyrosine-based inhibition motifs (ITIMs). When cross-linked, the intracellular domain was tyrosine phosphorylated and capable of recruiting tyrosine phosphatases, SHP-1 and SHP-2 and inositol polyphosphate 5-phosphatase, SHIP. LMIR2, on the other hand, contains a short cytoplasmic tail and a characteristic transmembrane domain carrying two positively charged amino acids associated with three kinds of immunoreceptor tyrosine-based activation motif (ITAM)-bearing molecules, DAP10, DAP12, and FcRgamma. These findings suggest that a new pair of ITIM/ITAM-bearing receptors, LMIR1 and 2, regulate mast cell-mediated inflammatory responses through yet to be defined ligand(s).