background: urinary organic acids are water-soluble intermediates and end products of the metabolism of amino acids, carbohydrates, lipids, and a number of other metabolic processes. in the hereditary diseases known as organic acidurias, an enzyme or co-factor defect in a metabolic pathway leads to the accumulation and increased excretion of one or more of these acidic metabolites. gas chromato...

Pitnenta is a genus of flowering plants in the Myrtaceae family, which has about 15 species, mostly found in the Caribbean region of the Americas. Commonly used for culinary and medicinal purposes, the best known commercial species are allspice, P. dioica (P. officinalis) and bay rum, P. racemosa, but there is little information concerning P. guatemalensis. The aim of the present study was to i...

A quantitative analysis of the individual compounds in tobacco essential oils is performed by comprehensive two-dimensional gas chromatography (GC x GC) combined with flame ionization detector (FID). A time-of-flight mass spectrometer (TOF/MS) was coupled to GC x GC for the identification of the resolved peaks. The response of a flame ionization detector to different compound classes was calibr...

The purpose of this research was to produce cocoa butter equivalent from the blend of mango seed almond fat (MAF) from “Keaw” variety mango kernels and palm oil mid-fraction (POMF). Seven MAF-POMF blends with different proportions (100/0, 90/10, 80/20, 70/30, 60/40, 50/50 and 0/100 (%wt) of MAF to POMF) including cocoa butter were characterized using various techniques. Fatty acid composition w...

The characterization of essential oils of Mentha aquatica L grown in two Provinces of Vietnam was performed by means of gas chromatography-flame ionization detector (GC-FID) and gas chromatography-mass spectrometry (GC-MS) techniques. The major constituents of the essential oils were epi-bicyclosesquiphellandrene (58.9% and 52.4% respectively) and limonene (21.1% and 31.4% respectively) for Tha...

Hyphenated gas chromatography (GC) (Chaturvedi & Nanda, 2010; Coleman III & Gordon, 2006) mainly refers to the coupling of the high-performance separation technique of gas chromatography with 1) information-rich and sophisticated GC detectors which otherwise can be mostly operated as a stand-alone instrument for chemical analysis, and 2) automated online sample preparation systems. The term “hy...

An analytical method, based on separation with gas chromatography (GC) and detection with optical fiber (OF), was used for the separation, detection and quantification of benzene, toluene, ethylbenzene, p-xylene, m-xylene and o-xylene. The use of OF as a detector is based on the variations of the reflected optical power detected when the aromatic compounds eluted from the GC column are sorbed i...

the zinc-cadmium oxide (zno-cdo) nanocomposites with different weight percentages of cadmium oxide (cdo) nanoparticles were successfully synthesized by the sonochemical method using zinc and cadmium nitrates as precursors to probe their nano-structured surfaces for the decomposition reactions of chloroethyl phenyl sulfide (ceps) as a surrogate of sulfur mustard agent simulant. scanning electron...