Tetrandrine, a constituent of Chinese herb Stephania tetrandra, causes cell death in prostate cancer, but the molecular mechanisms leading to apoptosis is not known. Here we demonstrated that tetrandrine selectively inhibits the growth of prostate cancer PC3 and DU145 cells compared to normal pr...

BackgroundSleep disorders have been found to be associated with hypertension in both cross-sectional and longitudinal epidemiological studies. Tetrandrine, a major component of Stephania tetrandra, is well known as an antihypertensive agent. The anti-hypertension mechanism mainly relies on its L...

Proton magnetic resonance spectra at 220 MHz of mesoporphyrin IX dimethyl ester, deuteroporphyrin IX dimethyl ester, and protoporphyrin IX dimethyl ester are sufficiently resolved to show clearly that all of these compounds have surprisingly low symmetry. An examination of the concentration depe...

H2-mesoporphyrin IX and Zn-mesoporphyrin IX have been investigated as sensitizers for the titanium dioxide (TiO2) film electrode to construct a new two-compartment photoelectrochemical biofuel cell (PEBFC). The PEBFC can convert the light and chemical energy to electricity by consuming photons a...

From blossoms of Viola tricolor, four new naturally occurring geometrical isomers of violaxanthin (5,6,5′,6′-diepoxy-5,6,5′,6′-tetrahydro-β,β-carotene-3,3′-diol) have been isolated in the crystalline state. By two-dimensional 1H NMR methods, the new pigments are shown to be the 9,9′-, 9,...

Lutein, neoxanthin and violaxanthin are the main xanthophyll pigment constituents of the largest light-harvesting pigment–protein complex of photosystem II (LHCII). High performance liquid chromatography analysis revealed photoisomerization of LHCII-bound violaxanthin from the conformation all-...

A new cis isomer in the violaxanthin series has been isolated from the blossoms of Viola tricolor and identified by MS, IR and UV as the central-monocis form. It was converted to all-trans-violaxanthin by stereomutation. The CD correlation between 15-cis-violaxanthin and natural violaxanthin (5,...

The xanthophyll cycle is recognized as one of several mechanisms involved in the protection of plant membranes against damage resulting from excess excitation in high light. However, in most plants, only a proportion (typically ∼60%) of violaxanthin undergoes de-epoxidation into zeaxanthin. Whe...

Chlorophyll fluorescence excitation and emission spectroscopy, electron absorption spectroscopy and resonance Raman spectrometry of light-harvesting pigment-protein complex of Photosystem II (LHC II), isolated and incorporated to liposomes, indicate that a carotenoid pigment violaxanthin is pres...

A tin-containing compound, bis(triphenyltin) oxide (BTO), was added to two polymeric materials in an effort to reduce the erosion of the materials in the presence of atomic oxygen. The BTO was added to a solution of a thermoplastic polyetherimide, and to the amic acid solution of a polyimide the...

A combinational study of structural chemistry and dyestuff chemistry has been carried out to reveal the structure–performance relationship for eight disperse azo dyes by comparing their structures, electronic spectra, solvatochromism and theoretic computations. All eight structural analogues ha...

A photo-active nano-hybrid material consisting of titania nanoparticles, carminic acid, and sulphonic acid functionalized porphyrin is reported here. In an attempt to extend the absorption spectrum of titania to visible region by co-adsorbing carminic acid and sulphonic acid functionalized porph...

The role of siderite in catalyzing the H2O2 degradation of carmine was studied by using batch experiments. The effects of the size of siderite particles, ratio of H2O2 to siderite, initial pH, reaction time, and reaction temperature were examined, and the degradation mechanism and kinetics were ...

Hybrid materials based on one organic dye, the carminic acid, and montmorillonite have been prepared and characterized by a multi-technical approach. Aluminum and tin II cations were used in the experimental mixtures in order to have a chelating effect with the carminic acid. X-Ray diffraction p...

This article reports the synthesis of TiO2 nanotube arrays (TiO2 NTs), grown by Ti anodization, and their use as photoanode in a hybrid photelectrocatalytic (PEC)/photoelectro-Fenton (PEF) treatment of Indigo Carmine solutions in sulfate medium at pH 3.0. The anode was combined with an air-diffu...

Using the carminic acid assay, we determined the concentration of boron in oilfield waters. We investigated the effect of high concentrations of salts and dissolved metals on the assay performance. The influence of temperature, development time, reagent concentration, and water volume was studie...

The stepwise approach takes advantage of simple, versatile, low-cost screening tools that can be applied to several posts of the saffron trade chain to specifically detect adulteration with carminic acid (CA). This natural dye is of insect origin and should not be present in Kosher and Halal foo...

Late stage CH functionalization is a powerful tool for modification of natural compounds. Herein we report that the rhodium-catalyzed reaction of brassinosteroids with aryloxysulfonamides proceeds regio- and stereoselectively at C15 position. The derivative obtained from 24-epibrassinolide was e...

RésuméUn nouveau principe amer, la Glaucarubinone, a été isolé des graines de Simaruba glauca. Il est montré que cette substance a la formule (IIa).

p-21-Activated kinase 1 (PAK1) enhances colorectal cancer (CRC) progression by stimulating Wnt/β-catenin, ERK and AKT pathways. PAK1 also promotes CRC survival via up-regulation of hypoxia-inducible factor 1α (HIF-1α), a key player in cancer survival. Glaucarubinone, a quassinoid natural prod...