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Occurrence of fumonisins B1, B2 and B3 in maize-products commercialized in Italy and Spain
S234
Abstracts / Toxicology Letters 180S (2008) S32–S246
7.4 to 6.0 increased the initial uptake and the apical-to-basolateral transport of MCPA by about 4 and 10 times, respectively. Coincubation of MCPA with 10 mM benzoic acid or acetic acid, substrate of MCTs, from the apical side (pH 6.0) markedly decreased the uptake and the transport of MCPA from apical side to basolateral side (pH 7.4), whereas that with l-lactic acid, or alpha-cyano4-hydroxycinnamate, other type of MCPA substrate (inhibitor) marginally decreased those of MCPA. Furthermore, coincubation with succinic acid (dicarboxylic acid) did not decrease those of MCPA. These results support the previous conclusion that the uptake of MCPA from the apical membrane of Caco-2 cells is mediated by common MCTs along with benzoic acid but also in part by l-lactic acid. doi:10.1016/j.toxlet.2008.06.045 Z23 Occurrence of fumonisins B1 , B2 and B3 in maize-products commercialized in Italy and Spain Guillermina Font 1,∗ , Gilda D’Arco 2 , Monica Fernández 3 , Pietro ˜ 1 Damiani 4 , Jordi Manes 1
Laboratori de Bromatologia i Toxicologia, Facultat de Farmacia, Universitat de Valencia, Valencia, Spain, 2 Dipartimento di Science Economico-Estimative e degli Alimenti, Sezione di Chimica Bromatologica, Università degli Studi di Perugia, Perugia, Italy, 3 Universitat de Valencia, Valencia, Spain, 4 UniveDipartimento di Science Economico-Estimative e degli Alimenti, Sezione di Chimica Bromatologica, Università degli Studi di Perugia, Perugia, Italy Fumonisins are toxic and carcinogenic compounds produced by strains of fusarium species that can be readily found in maize and maize products. A survey of 186 samples of corn-based foods from different food products as baby foods (62), breakfast cereals (23), cookies (17), flours (13), pasta (14) and other foods (57) collected from Italian and Spanish markets during 2007 were studied for fumonisins B1 , B2 and B3 . Samples were analyzed by pressurized liquid extraction and liquid chromatography/electrospray ionization tandem mass spectrometry with a triple quadrupole (QqQ) analyzer. Of the 81 Italian samples analyzed, 32% were positive with quantifiable levels lower than 234, 187 and 70 mg kg−1 for fumonisins B1 , B2 and B3 , respectively. On the other hand, 33% of the 105 samples of Spanish markets were positive with levels lower than 449, 229 and 105 mg kg−1 for fumonisins B1 , B2 and B3 , respectively. None of the Italian samples and only one organic baby food from a Spanish market was above the maximum residue levels established by the European legislation. Eleven samples from Spain and nine samples from Italy were organic, being contaminated in that order 90% and 66%. Analysis of the obtained results showed that levels of fumonisins in corn products were similar in Italy and Spain. The safety of the intake of corn products by the population was demonstrated by comparing the low estimated daily intake with the tolerable daily intake of 2 g kg−1 bw/day established by the European Union. doi:10.1016/j.toxlet.2008.06.046
Z24 Glucose influence on copper ion-dependent oxidation of native and glycated low density lipoprotein Mohammad Ali Ghaffari ∗ , Samad Mojab Ahwaz Jundishapour University of Medical Sciences, Ahwaz, Kozestan, Islamic Republic of Iran Introduction: It is well established that oxidative modification of low density lipoprotein (LDL) plays a causal role in human atherogenesis and the risk of atherosclerosis is increased in patients with diabetes mellitus. We examined the in vitro effect of glucose on native and glycated LDL oxidation using copper ion dependent oxidation system. Methods: In this study, LDL was isolated from plasma by ultracentrifugation using a single step discontinuous gradient. Native LDL preparations were glycated by glucose and it’s also were oxidized by copper ions. LDL glycation and oxidation levels were estimated by sodium periodate assay and thiobarbitoric acid reactive substances (TBARS), respectively. Then native LDL incubated with glucose and copper and LDL oxidation was estimated by TBARS. Finally, oxidation of glycated LDL was studied in presence of copper ions by TBARS and relative electrophoretic mobility on polyacrylamide gel. Results: This study was showed that glucose considerably decreased the oxidation of native LDL by copper ions. But oxidation of glycated LDL elevated with presence of copper ions. Discussion: The results of this investigation show that LDL glycated in vitro is prone to oxidation by copper ions. Thus promotion of glycated LDL oxidation by glucose is specific for copper ion dependent oxidation and involves increased copper ion reduction. These results provide one mechanism that may enhanced LDL oxidation in diabetes and thus contribute to the pathogenesis of atherosclerosis in diabetic patients. Keywords: Low density lipoprotein (LDL); Glucose; Copper; Glycation; Oxidation doi:10.1016/j.toxlet.2008.06.047 Z25 Erum ochratoxin a levels in healthy Turkish subjects Pinar Erkekoglu ∗ , Suna Atasayar, Sevtap Aydin, Gonul Sahin, Belma Giray Hacettepe University Faculty of Pharmacy, Ankara, Turkey The present study was aimed to determine serum ochratoxin A (OTA) concentrations in healthy subjects from different regions of Turkey. Therefore, blood samples were collected from 120 healthy volunteers of all ages in Black Sea and Mediterranean regions. Serum OTA concentrations were measured by ELISA technique and found to be 0.55 ± 0.12 ng/ml in children (n = 15); 0.27 ± 0.07 ng/ml in adults (n = 31) and 0.12 ± 0.01 ng/ml in elderly people (n = 14) in Black Sea Region. In Mediterranean region, the mean OTA levels were determined to be 0.15 ± 0.03 ng/ml, 0.37 ± 0.06 ng/ml and 0.33 ± 0.11 ng/ml in children, adult and elderly volunteers, respectively. The difference between the levels in adults and children was found to be statistically significant in both regions and the highest serum OTA levels were determined in the children lived in Black Sea Region. On the other hand, the daily intake levels of OTA in Black Sea and Mediterranean regions were calculated as 0.56 ± 0.11 and 0.44 ± 0.06 ng/kg bw/day, respectively and these levels were lower than the tolerable daily intake proposed by Joint FAO/WHO Expert
Abstracts / Toxicology Letters 180S (2008) S32–S246
7.4 to 6.0 increased the initial uptake and the apical-to-basolateral transport of MCPA by about 4 and 10 times, respectively. Coincubation of MCPA with 10 mM benzoic acid or acetic acid, substrate of MCTs, from the apical side (pH 6.0) markedly decreased the uptake and the transport of MCPA from apical side to basolateral side (pH 7.4), whereas that with l-lactic acid, or alpha-cyano4-hydroxycinnamate, other type of MCPA substrate (inhibitor) marginally decreased those of MCPA. Furthermore, coincubation with succinic acid (dicarboxylic acid) did not decrease those of MCPA. These results support the previous conclusion that the uptake of MCPA from the apical membrane of Caco-2 cells is mediated by common MCTs along with benzoic acid but also in part by l-lactic acid. doi:10.1016/j.toxlet.2008.06.045 Z23 Occurrence of fumonisins B1 , B2 and B3 in maize-products commercialized in Italy and Spain Guillermina Font 1,∗ , Gilda D’Arco 2 , Monica Fernández 3 , Pietro ˜ 1 Damiani 4 , Jordi Manes 1
Laboratori de Bromatologia i Toxicologia, Facultat de Farmacia, Universitat de Valencia, Valencia, Spain, 2 Dipartimento di Science Economico-Estimative e degli Alimenti, Sezione di Chimica Bromatologica, Università degli Studi di Perugia, Perugia, Italy, 3 Universitat de Valencia, Valencia, Spain, 4 UniveDipartimento di Science Economico-Estimative e degli Alimenti, Sezione di Chimica Bromatologica, Università degli Studi di Perugia, Perugia, Italy Fumonisins are toxic and carcinogenic compounds produced by strains of fusarium species that can be readily found in maize and maize products. A survey of 186 samples of corn-based foods from different food products as baby foods (62), breakfast cereals (23), cookies (17), flours (13), pasta (14) and other foods (57) collected from Italian and Spanish markets during 2007 were studied for fumonisins B1 , B2 and B3 . Samples were analyzed by pressurized liquid extraction and liquid chromatography/electrospray ionization tandem mass spectrometry with a triple quadrupole (QqQ) analyzer. Of the 81 Italian samples analyzed, 32% were positive with quantifiable levels lower than 234, 187 and 70 mg kg−1 for fumonisins B1 , B2 and B3 , respectively. On the other hand, 33% of the 105 samples of Spanish markets were positive with levels lower than 449, 229 and 105 mg kg−1 for fumonisins B1 , B2 and B3 , respectively. None of the Italian samples and only one organic baby food from a Spanish market was above the maximum residue levels established by the European legislation. Eleven samples from Spain and nine samples from Italy were organic, being contaminated in that order 90% and 66%. Analysis of the obtained results showed that levels of fumonisins in corn products were similar in Italy and Spain. The safety of the intake of corn products by the population was demonstrated by comparing the low estimated daily intake with the tolerable daily intake of 2 g kg−1 bw/day established by the European Union. doi:10.1016/j.toxlet.2008.06.046
Z24 Glucose influence on copper ion-dependent oxidation of native and glycated low density lipoprotein Mohammad Ali Ghaffari ∗ , Samad Mojab Ahwaz Jundishapour University of Medical Sciences, Ahwaz, Kozestan, Islamic Republic of Iran Introduction: It is well established that oxidative modification of low density lipoprotein (LDL) plays a causal role in human atherogenesis and the risk of atherosclerosis is increased in patients with diabetes mellitus. We examined the in vitro effect of glucose on native and glycated LDL oxidation using copper ion dependent oxidation system. Methods: In this study, LDL was isolated from plasma by ultracentrifugation using a single step discontinuous gradient. Native LDL preparations were glycated by glucose and it’s also were oxidized by copper ions. LDL glycation and oxidation levels were estimated by sodium periodate assay and thiobarbitoric acid reactive substances (TBARS), respectively. Then native LDL incubated with glucose and copper and LDL oxidation was estimated by TBARS. Finally, oxidation of glycated LDL was studied in presence of copper ions by TBARS and relative electrophoretic mobility on polyacrylamide gel. Results: This study was showed that glucose considerably decreased the oxidation of native LDL by copper ions. But oxidation of glycated LDL elevated with presence of copper ions. Discussion: The results of this investigation show that LDL glycated in vitro is prone to oxidation by copper ions. Thus promotion of glycated LDL oxidation by glucose is specific for copper ion dependent oxidation and involves increased copper ion reduction. These results provide one mechanism that may enhanced LDL oxidation in diabetes and thus contribute to the pathogenesis of atherosclerosis in diabetic patients. Keywords: Low density lipoprotein (LDL); Glucose; Copper; Glycation; Oxidation doi:10.1016/j.toxlet.2008.06.047 Z25 Erum ochratoxin a levels in healthy Turkish subjects Pinar Erkekoglu ∗ , Suna Atasayar, Sevtap Aydin, Gonul Sahin, Belma Giray Hacettepe University Faculty of Pharmacy, Ankara, Turkey The present study was aimed to determine serum ochratoxin A (OTA) concentrations in healthy subjects from different regions of Turkey. Therefore, blood samples were collected from 120 healthy volunteers of all ages in Black Sea and Mediterranean regions. Serum OTA concentrations were measured by ELISA technique and found to be 0.55 ± 0.12 ng/ml in children (n = 15); 0.27 ± 0.07 ng/ml in adults (n = 31) and 0.12 ± 0.01 ng/ml in elderly people (n = 14) in Black Sea Region. In Mediterranean region, the mean OTA levels were determined to be 0.15 ± 0.03 ng/ml, 0.37 ± 0.06 ng/ml and 0.33 ± 0.11 ng/ml in children, adult and elderly volunteers, respectively. The difference between the levels in adults and children was found to be statistically significant in both regions and the highest serum OTA levels were determined in the children lived in Black Sea Region. On the other hand, the daily intake levels of OTA in Black Sea and Mediterranean regions were calculated as 0.56 ± 0.11 and 0.44 ± 0.06 ng/kg bw/day, respectively and these levels were lower than the tolerable daily intake proposed by Joint FAO/WHO Expert