A sensory evaluation of irradiated cookies made from flaxseed meal

The growing consumer demand for food with sensory quality and nutritional has called for research to develop new products with consumer acceptance as cookies made from flaxseed meal, that can be inserted in diet of celiacs. Celiac disease characterized by an inappropriate immune response to dietary proteins found in wheat, rye and barley (gluten and gliadin). It can affect anyone at any age and is more common in women. The celiac disease does not have cure and the only scientifically proven treatment is a gluten free diet. Irradiation as a decontamination method used for a many variety of foodstuffs, being very feasible, useful method to increase the shelf life, effective and environmental friendly without any sensory properties significant change. Sensory analyses were used to assess gluten-free bakery foods subjected to ionizing radiation sensory attributes.     

Simultaneous quantitation of sphingoid bases and their phosphates in biological samples by liquid chromatography/electrospray ionization tandem mass spectrometry

We developed a liquid chromatography/electrospray ionization tandem mass spectrometry method for the simultaneous quantitative determination of C18 sphingosine (Sph), C18 dihydrosphingosine (dhSph), C18 phytosphingosine (pSph), C18 sphingosine-1-phosphate (S1P), C18 dihydrosphingosine-1-phosphate (dhS1P), and C18 phytosphingosine-1-phosphate (pS1P). Samples were prepared by simple methanol deproteinization and analyzed in selected reaction monitoring modes. No peak tailing was observed on the chromatograms using a Capcell Pak ACR column (1.5 mm i.d. × 250 mm, 3 μm, Shiseido). The calibration curves of the sphingoids showed good linearity (r > 0.996) over the range of 0.050-5.00 pmol per injection. The accuracy and precision of this method were demonstrated using four representative biological samples (serum, brain, liver, and spleen) from mice that contained known amounts of the sphingoids. Samples of mice tissue such as plasma, brain, eye, testis, liver, kidney, lung, spleen, lymph node, and thymus were examined for their Sph, dhSph, pSph, S1P, dhS1P, and pS1P composition. The results confirmed the usefulness of this method for the physiological and pathological analysis of the composition of important sphingoids.     

Sunlight-driven synthesis of γ-diketones via oxidative coupling of enamines with silyl enol ethers catalyzed by [Ru(bpy)3]2+

A photosensitizer [Ru(bpy)(3)](2+) catalyzes oxidative coupling reaction of enamines with silyl enol ethers under visible light irradiation by a Xe lamp or sunlight to produce γ-diketones. A 2e-oxidation process involved in this reaction is achieved by a combination of the photoexcited [Ru(bpy)(3)](2+) species and duroquinone, a 2e-acceptor.     

Sensitive Detection of Small Molecule–Protein Interactions on a Metal–Insulator–Metal Label‐Free Biosensing Platform

The need to develop label‐free biosensing devices that enable rapid analyses of interactions between small molecules/peptides and proteins for post‐genomic studies has increased significantly. We report a simple metal–insulator–metal (MIM) geometry for fabricating a highly sensitive detection platform for biosensing. MIM substrates consisting of an Au–PMMA–Ag nanolayer were extensively studied using both theoretical and experimental approaches. By monitoring reflectivity changes at the normal incidence angle, we observed molecular interactions as the thickness of the biolayer increased on the substrate surface. These interactions included the adsorption of various proteins (Mw=6–150 kD) and interactions between small molecules (Mw≤2 kD) and the immobilized proteins. The interaction of designed monosaccharide‐modified designed peptides with various lectins was also clearly detected. These interactions could not be detected by the conventional Au‐only substrate. Thus, the MIM approach affords a powerful label‐free biosensing device that will aid our understanding of protein interactions and recognition.     

Real light emitter in the bioluminescence of the calcium-activated photoproteins aequorin and obelin: light emission from the singlet-excited state of coelenteramide phenolate anion in a contact ion pair

Fluorescence of the phenolate anion (3(O)⁻) and the amide anion (5(N)⁻) of coelenteramide analogues in ion pairs with various counter cations was systematically investigated to elucidate the ionic structure of the light emitter in the bioluminescence of the calcium-activated photoproteins aequorin and obelin. The fluorescent properties of 3(O)⁻ in an ion pair with a conjugate acid of an organic base (BASE-H⁺) were varied depending on the structural variation of the ion pair and the solvent polarity. In particular, the fluorescence of 3(O)⁻ in the ion pair with the conjugate acid of n-butylamine (NBA-H⁺) indicates that the singlet-excited state of 3(O)⁻ (¹3(O)^−∗) and NBA-H⁺ make a contact ion pair in which the fluorescence emission maxima of 3(O)⁻ is sensitive to the solvent polarity and the fluorescence quantum yields of 3(O)⁻ increase in a less polar solvent. The results also confirm that ¹3(O)^−∗ is a twisted intramolecular charge transfer state. By contrast, the fluorescence of 5(N)⁻ in an ion pair depends little on the BASE-H⁺ or the solvent polarity. Based on these results, we conclude that the light emitter in aequorin and obelin bioluminescences is the singlet-excited state of coelenteramide phenolate anion 2(O)⁻ (¹2(O)^−∗) in a contact ion pair with an imidazolium side chain of a histidine residue, which is located at the less polar active sites of the photoproteins. We also propose a mechanism for the bioluminescence reaction, including the chemiexcitation process to give ¹2(O)^−∗.     

Maskless microfabrication of thermosensitive gels using a microscope and application to a controlled release microchip

Here we show a simple and convenient method to prepare micropatterned gels by the use of a microscope, without large-scale or special-order experimental setup. UV light focused by an objective lens was locally irradiated to a pre-gel solution in a microchannel. This method would be useful for preparing microgels at target positions in microchips. A controlled drug-release microchip has actually been fabricated by utilizing this local photo-irradiation method, and pulsatile drug release in response to temperature changes was demonstrated.     

A new quassinoid, ailantinol H, from Ailanthus altissima

A new quassinoid, ailantinol H, was isolated from the aerial parts of Ailanthus altissima. The structure was elucidated based on spectral evidence.     

Function of membrane protein in silica nanopores: incorporation of photosynthetic light-harvesting protein LH2 into FSM

A high amount of functional membrane protein complex was introduced into a folded-sheet silica mesoporous material (FSM) that has nanometer-size pores of honeycomb-like hexagonal cylindrical structure inside. The photosynthetic light-harvesting complex LH2, which is a typical membrane protein, has a cylindrical structure of 7.3 nm diameter and contains 27 bacteriochlorophyll a and nine carotenoid molecules. The complex captures light energy in the anoxygenic thermophilic purple photosynthetic bacterium Thermochromatium tepidum. The amount of LH2 adsorbed to FSM was determined optically and by the adsorption isotherms of N2. The FSM compounds with internal pore diameters of 7.9 and 2.7 nm adsorbed LH2 at 1.11 and 0.24 mg/mg FSM, respectively, suggesting the high specific affinity of LH2 to the interior of the hydrophobic nanopores with a diameter of 7.9 nm. The LH2 adsorbed to FSM showed almost intact absorption bands of bacteriochlorophylls, and was fully active in the capture and transfer of excitation energy. The LH2 complex inside the FSM showed increased heat stability of the exciton-type absorption band of bacteriochlorophylls (B850), suggesting higher circular symmetry. The environment inside the hydrophobic silica nanopores can be a new matrix for the membrane proteins to reveal their functions. The silica-membrane protein adduct will be useful for the construction of new probes and reaction systems.     

Stereogradient polymers by ruthenium-catalyzed stereospecific living radical copolymerization of two monomers with different stereospecificities and reactivities

Stereogradient polymers, a fundamentally new type of polymers, were prepared by the stereospecific living radical copolymerization of two monomers that have different stereospecificities and reactivities. The ruthenium-catalyzed living radical copolymerization of 2-hydroxyethyl methacrylate (HEMA) and the silyl-capped HEMA [(tert-butyldimethylsilyl)-HEMA] (SiHEMA) in (CF3)2C(Ph)OH afforded stereogradient poly(HEMA), in which the rr content gradually increased from 62 to 77% at 0 degrees C, due to the lower reactivity and the higher syndiospecificity of SiHEMA.