A simple and rapid microextraction procedure based on dispersive liquid-liquid microextraction (DLLME) was developed for determination and speciation of trace amounts of chromium (Cr) by flame atomic absorption spectrometry (FAAS). In the proposed approach, chloroform and methanol were used as extraction and dispersive solvents. A new Schiff's base ligand, bis(2-methoxy benzaldehyde) ethylene d...

urinary 1-hydroxypuren (1-ohp) is commonly used as a major metabolite and biological indicator of the overall exposure to polycyclic aromatic hydrocarbons (pahs). for evaluation of human exposure to such compounds, biological monitoring is an essential process, in which, preparation of samples is one of the most time-consuming and error-prone aspects prior to chromatographic techniques. in this...

Surface induced smectic order was found for the ionic liquid 1-methyl-3-docosylimidazolium bis(trifluoromethlysulfonyl)imide by X-ray reflectivity and grazing incidence scattering experiments. Near the free liquid surface, an ordered structure of alternating layers composed of polar and non-polar moieties is observed. This leads to an oscillatory interfacial profile perpendicular to the liquid ...

EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA); Scientific Opinion on the substantiation of health claims related to L-theanine from Camellia sinensis (L.) Kuntze (tea) and improvement of cognitive function (ID 1104, 1222, 1600, 1601, 1707, 1935, 2004, 2005), alleviation of psychological stress (ID 1598, 1601), maintenance of normal sleep (ID 1222, 1737, 2004) and reduction of m...

The critical Casimir force (CF) is observed in thin wetting films of a binary liquid mixture close to the liquid/vapor coexistence. X-ray reflectivity shows thickness (L) enhancement near the bulk consolute point. The extracted Casimir amplitude Delta(+-)=3+/-1 agrees with the theoretical universal value for the antisymmetric 3D Ising films. The onset of CF in the one-phase region occurs at L/x...

Previously, we revealed that theanine, a green tea component, induced phospholipase C (PLC)-beta1 and -gamma1, stress-responsible molecules, in primary cultured rat cerebral cortical neurons, suggesting its protective effect on oxidative stress in neurons. In this study, we investigated whether the same favorable effect occurs in vivo. On the oral administration of theanine (10 mmol (1.74 g)/kg...

298 Introduction Environmental and biological analyses are especially challenging for the analyst because sample matrices tend to be very complex and the analytes are present at very low levels. Selective and sensitive methods are needed for both sample preparation and analysis. Typically, extraction and clean-up are needed in the sample preparation, and the analyses are performed by chromatogr...

Theanine is an amide exclusively present in tea and some fungi, and is an important bioactive component of tea. The bioactive effects of theanine include antitumour, anti-diabetic, antihypertensive, anti-stress activities, and the ability to improve cardiovascular and cerebrovascular diseases. It also has protective effect on nerve cells against damage induced by environmental neurotoxins as we...

recovery of metabolites from fermentation broth by solvent extraction can be used to optimize fermentation processes. end-product reutilization, low product concentration and large volumes of fermentation broth and the requirements for large bioreactors, in addition to the high cost largely contributed to the decline in fermentative 2,3-butanediol production. extraction can successfully be used...