Search results for "toxin"
showing 10 items of 1434 documents
DNA binding, nuclease activity, DNA photocleavage and cytotoxic properties of Cu(II) complexes of N-substituted sulfonamides.
2013
Abstract Ternary copper(II) complexes [Cu(NST)2(phen)] (1) and [Cu(NST)2(NH3)2]·H2O (2) [HNST = N-(4,5-dimethylthiazol-2-yl)naphthalene-1-sulfonamide] were prepared and characterized by physico-chemical techniques. Both 1 and 2 were structurally characterized by X-ray crystallography. The crystal structures show the presence of a distorted square planar CuN4 geometry in which the deprotonated sulfonamide, acting as monodentate ligand, binds to the metal ion through the thiazole N atom. Both complexes present intermolecular π–π stacking interactions between phenanthroline rings (compound 1) and between naphthalene rings (compound 2). The interaction of the complexes with CT DNA was studied b…
Indoor air quality in schools of a highly polluted south Mediterranean area
2019
This study aimed at surveying lower secondary schools in southern Italy, in a highly polluted area. A community close to an industrial area and three villages in rural areas was investigated. Indoor temperature, relative humidity (RH), gaseous pollutants (CO 2 and NO 2 ), selected biological pollutants in indoor dust, and the indoor/outdoor mass concentration and elemental composition of PM 2.5 were ascertained. Temperature and RH were within, or close to, the comfort range, while CO 2 frequently exceeded the threshold of 1000 ppm, indicating inadequate air exchange rate. In all the classrooms, median NO 2 levels were above the WHO threshold value. Dermatophagoides p. allergen concentration…
Comparison and improvement of the existing methods for the determination of aflatoxins in human serum by LC-MS/MS
2010
Aflatoxins are toxic metabolites of some Aspergillus flavus, A. parasiticus and A. nomius strains that occur in many foods and feeds. Aflatoxin B1 is the most abundant and toxic member of the family, and it is also the most potent hepatocarcinogen known. In order to estimate the potential human health risk of aflatoxin B1, it is useful to measure its blood concentration. In this work a rapid liquid chromatography coupled to mass spectrometry (LC-MS/MS) method for the simultaneous determination of aflatoxins B1, B2, G1 and G2 and its metabolites, aflatoxins M1 and M2 in human serum, is proposed. Small serum volumes have been used and the extracts have been obtained without any clean-up proce…
Quantitative determination of moniliformin in vegetable foods and feeds
1984
A suitable and simple method for the quantitative determination of moniliformin in vegetable foods and feeds is described. The mycotoxin was extracted by Soxhlet extraction with methanol from mouldy maize, rice, rye, oats, wheat and barley samples. Moniliformin was determined by thin-layer chromatography (TLC) using N-methylbenzthiazolon-2-hydrazone (MBTH) as a new derivatization reagent for this mycotoxin. The moniliformin derivative was assayed at 518 nm. Quantification could be performed after calibration. A linear relationship between mycotoxin amount and peak area was found from 100 to 400 ng/spot. The detection limit is 75 ng/spot.
Analysis of T-2 toxin by HPLC and GC in samples of corn and oats
1984
HPLC is the only physico-chemical method for the analysis of trichothecenes for which no derivatization is necessary. Hence a combination of different methods can be performed. For exclusion of any faulty interpretation of data and in order to decrease the detection limit HPLC should be followed by GC.
Rapid whole protein quantification of staphylococcal enterotoxin B by liquid chromatography
2012
Abstract Food poisoning caused by Staphylococcus aureus is one of the most important foodborne diseases in the world. The ability of these bacteria to produce one or more enterotoxins in milk and dairy products is linked to staphylococcal food poisoning. Enterotoxin B (SEB) is an exotoxin produced by S. aureus and is one of the compounds most frequently involved in staphylococcal food poisoning worldwide. In this work, 20 samples of milk collected from restaurants have been studied for the presence of S. aureus enterotoxigenic strains. All the isolates from milk samples have been analysed by liquid chromatography-coupled with diode array detector for the rapid identification and quantificat…
Comparative assessment of three extraction procedures for determination of emerging Fusarium mycotoxins in pasta by LC–MS/MS
2013
Abstract A new rapid, sensitive, reproducible and reliable method was developed for the quantitative determination of enniatins A, A1, B and B1, beauvericin and fusaproliferin in dry and fresh pasta by liquid chromatography-triple quadrupole-tandem mass spectrometry. A comparative study of different rapid and economical extraction procedures was performed for the extraction of these mycotoxins in pasta. For this purpose, three different approaches were studied during the extraction step (Ultra-Turrax, ultrasonic bath and microwave). Optimal extraction conditions were reached using Ultra-Turrax with acetonitrile for 3 min without purification step. The chromatographic separation of the six m…
Optimization of clean-up procedure for patulin determination in apple juice and apple purees by liquid chromatography
2009
Patulin (PAT) is a mycotoxin produced in fruits, mainly in apples, by several fungal species that can be carried into industrial apple juice by-products during factory processing. An analytical method for determination of PAT in apple juice and another one for determination of this compound in apple purees and apple compotes by liquid chromatography are proposed in the present paper. These methods have better precision and sensitivity than previously reported methods and focus mainly on extraction and clean-up. To accomplish analytical methods with higher accuracy, lower limits of detection and simpler procedures for application in quality control of the goods, different extraction and clea…
Optimization of Matrix Solid-Phase Dispersion method for simultaneous extraction of aflatoxins and OTA in cereals and its application to commercial s…
2010
Abstract A method based on Matrix Solid-Phase Dispersion (MSPD) has been developed for the determination of 5 mycotoxins (ochratoxin A and aflatoxins B and G) in different cereals. Several dispersants, eluents and ratios were tested during the optimization of the process in order to obtain the best results. Finally, samples were blended with C 18 and the mycotoxins were extracted with acetonitrile. Regarding to matrix effects, the results clearly demonstrated the necessity to use a matrix-matched calibration to validate the method. Analyses were performed by liquid chromatography–triple quadrupole-tandem mass spectrometry (LC–QqQ-MS/MS). The recoveries of the extraction process ranged from …
Simple liquid chromatography assay for analyzing ochratoxin A in bovine milk
2008
Abstract Ochratoxin A (OTA) is a mycotoxin with teratogenic and carcinogenic properties. Animal intake of feedstuffs contaminated with OTA may cause that some residues may be found in bovine milk, therefore, its analysis requires a highly sensitive, simple and precise technique. This method is based on a liquid–liquid extraction with methanol, followed by filtration and extract concentration. Liquid chromatography coupled to fluorescence detection was used for OTA analysis. In this way, several impurities are filtered off and OTA is quantified with a mean recovery of 93.0 ± 7.4% and a limit of detection of 0.01 ng mL −1 . Therefore, this methodology allows a simple quantitative extraction o…