biogenic amines (ba) are nitrogenous compounds that possess biological activity. the source of production is the microbial decarboxylation of amino acids. this compounds are found in various types of cheese. the aim of this work was to evaluate the ba content of some traditional cheeses in west azerbaijan province iran. for this purpose, 70 samples of koopeh, 10 samples of lighvan and 5 samples...

use of raw milk and dairy products containing aflatoxin m1 (afm1) has led to concern inconsumers. the present study determined the afm1 in raw cow's milk in qazvinprovince. in this research, 170 raw cow's milk were collected from dairy farm, dairyfactories, milk collection centers, and milk supply centers in qazvin province during coldseasons in 2013, and all samples were examined for afm1. the...

oligosaccharide prepared from Pl.-B was eluted as a single peak on both reversed-phase {RP-) HPLC and size-fractionation (SF-) HPLC, and its strueture was estimated to be Manoct-qManal -. 3)(Xylfi1-.2) Manfi1-4GlcNAcfi1-4(Fuc=1-3)GlcNAc by a combination of component analysis, successive exogl)'cosidase digestions, IS-MS anal)'sis, and 500MHz 'H-NMR, Two tryptic gl)'copeptides were isolated from...

Filtration is a common method of sample preparation in dissolution testing, prior to HPLC injection. The purpose of sample filtration is to remove non-dissolved solids prior to HPLC injection. Non-dissolved solids interfere with the resulting chromatography by continuing to dissolve throughout the period of the analysis and also by plugging the HPLC column. It has already been shown that sample...

PURPOSE To analyze and compare the high performance liquid chromatography (HPLC) runs of tear proteins from diabetic (DIDRY) and non-diabetic (DRY) dry-eye patients, and healthy subjects (CTRL). The patterns were analyzed using multivariate statistical methods. METHODS Tears (total 56 eyes: CTRL: n=16, DIDRY: n=21, and DRY: n=19) were analyzed by HPLC, using a size-exclusion column with an el...

Mycolic acids extracted from saponified mycobacterial cells were examined as p-bromophenacyl esters by high-performance liquid chromatography (HPLC). Standard HPLC patterns were developed for species of Mycobacterium by examination of strains from culture collections and other well-characterized isolates. Relative retention times of peaks and peak height comparisons were used to develop a diffe...

Five different methods for the determination of 3-methoxy-4-hydroxymandelic acid (vanilmandelic acid, VMA) in urine were compared: a GLC-FID catecholamine metabolite profiling method, an HPLC method with electrochemical detection, the method of Pisano et al. [1962) Clin. Chim. Acta 7, 285-291), a one dimensional paper chromatographic method with diazotized p-nitroaniline staining and the commer...

Dereplication and chemotaxonomic studies of six marine algae of the Ochrophyta and one of the Rhodophyta phyla resulted in the detection of 22 separate compounds. All 16 secondary metabolites, including four new compounds (16-19), could be rapidly dereplicated using HPLC-NMR and HPLC-MS methodologies in conjunction with the MarinLit database. This study highlights the advantages of using NMR da...

This study describes a multistage methodology to detect minute amounts of tetrodotoxin in fishes, plan that may be broadened include other marine organisms. was applied porcupinefish (Diodon hystrix) collected Punta Chiquirín, El Salvador. A three-stage approach along with post-acquisition processing employed, wit: (a) Sample screening by selected reaction monitoring (HPLC-MS/MS-SRM) analyses q...