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1.
Ecotoxicol Environ Saf ; 269: 115804, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38091671

RESUMO

The cyanotoxin cylindrospermopsin (CYN) has been postulated to cause neurotoxicity, although the studies in this concern are very few. In addition, some studies in vitro indicate its possible effects on development. Furthermore, pesticides can be present in the same environmental samples as cyanotoxins. Therefore, chlorpyrifos (CPF) has been one of the most common pesticides used worldwide. The aim of this report was to study the effects of CYN, isolated and in combination with CPF, in a developmental neurotoxicity in vitro model. The human neuroblastoma SH-SY5Y cell line was exposed during 6 days of differentiation to both toxics to study their effects on cell viability and neurite outgrowth. To further evaluate effects of both toxicants on cholinergic signaling, their agonistic and antagonistic activities on the α7 homomeric nicotinic acetylcholine receptor (nAChR) were studied upon acute exposure. Moreover, a transcriptomic analysis by qPCR was performed after 6 days of CYN-exposure during differentiation. The results showed a concentration-dependent decrease on both cell viability and neurite outgrowth for both toxics isolated, leading to effective concentration 20 (EC20) values of 0.35 µM and 0.097 µM for CYN on cell viability and neurite outgrowth, respectively, and 100 µM and 58 µM for CPF, while the combination demonstrated no significant variations. In addition, 95 µM and 285 µM CPF demonstrated to act as an antagonist to nicotine on the nAChR, although CYN up to 2.4 µM had no effect on the efficacy of these receptors. Additionally, the EC20 for CYN (0.097 µM) on neurite outgrowth downregulated expression of the 5 genes NTNG2 (netrin G2), KCNJ11 (potassium channel), SLC18A3 (vesicular acetylcholine transporter), APOE (apolipoprotein E), and SEMA6B (semaphorin 6B), that are all important for neuronal development. Thus, this study points out the importance of studying the effects of CYN in terms of neurotoxicity and developmental neurotoxicity.


Assuntos
Alcaloides , Clorpirifos , Toxinas de Cianobactérias , Neuroblastoma , Síndromes Neurotóxicas , Praguicidas , Humanos , Clorpirifos/toxicidade , Receptor Nicotínico de Acetilcolina alfa7/genética , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Netrinas/metabolismo , Proteínas Ligadas por GPI/metabolismo
2.
Ecotoxicol Environ Saf ; 191: 110222, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31982683

RESUMO

Cylindrospermopsin (CYN) is a cyanotoxicant which occurrence is increasing due to climate change. Cylindrospermopsin is able to exert damage in the organism at several levels, among them, in the nervous system. Moreover, it is important to take into account that it is not usually present isolated in nature, but in combination with some other pollutants, being the case of the pesticide chlorpyrifos (CPF). Thus, the aim of the present work was to assess the effects of the interaction of CYN in combination with CPF in the human neuroblastoma cell line SH-SY5Y by evaluating cytotoxicity and mechanistic endpoints. The mixtures 0.25 + 21, 0.5 + 42, 1 + 84 µg/mL of CYN + CPF based on cytotoxicity results, were evaluated, and the isobologram method detected an antagonistic effect after 24 and 48 h of exposure. Moreover, although no alterations of reactive oxygen species were detected, a significant decrease of glutathione levels was observed after exposure to both, CPF alone and the combination, at all the concentrations and times of exposure assayed. In addition, CYN + CPF caused a marked decrease in the acetylcholinesterase activity, providing similar values to CPF alone. However, these effects were less severe than expected. All these findings, together with the morphological study results, point out that it is important to take into account the interaction of CYN with other pollutants. Further research is required to contribute to the risk assessment of CYN and other contaminants considering more realistic exposure scenarios.


Assuntos
Toxinas Bacterianas/toxicidade , Clorpirifos/toxicidade , Inibidores da Colinesterase/toxicidade , Poluentes Ambientais/toxicidade , Inseticidas/toxicidade , Uracila/análogos & derivados , Alcaloides , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Toxinas de Cianobactérias , Glutationa/metabolismo , Humanos , Uracila/toxicidade
3.
J Water Health ; 12(1): 69-80, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24642434

RESUMO

Cyanobacteria are able to produce several metabolites that have toxic effects on humans and animals. Among these cyanotoxins, the hepatotoxic microcystins (MC) occur frequently. The intracellular MC content produced by two strains of Microcystis aeruginosa, PCC7806 and PCC7820, and its production kinetics during the culture time were studied in order to elucidate the conditions that favour the growth and proliferation of these toxic strains. Intracellular MC concentrations measured by liquid chromatography (LC) coupled to electrospray ionization mass spectrometer (MS) were compared with those obtained by enzyme-linked immunosorbent assay (ELISA) anti-Adda and protein phosphatase 2A (PP2A) inhibition assays. It has been demonstrated there are discrepancies in the quantification of MC content when comparing ELISA and LC-MS results. However, a good correlation has been obtained between PP2A inhibition assay and LC-MS. Three MC were identified using LC-MS in the PCC7806 strain: MC-LR, demethylated MC-LR and a new variant detected for the first time in this strain, [L-MeSer(7)] MC-LR. In PCC7820, MC-LR, D-Asp(3)-MCLR, Dglu(OCH3)-MCLR, MC-LY, MC-LW and MC-LF were identificated. The major one was MC-LR in both strains, representing 81 and 79% of total MC, respectively. The total MC content in M. aeruginosa PCC7820 was almost three-fold higher than in PCC7806 extracts.


Assuntos
Microcistinas/metabolismo , Microcystis/crescimento & desenvolvimento , Microcystis/metabolismo , Bioensaio/métodos , Calcineurina/análise , Técnicas de Cultura de Células , Cromatografia Líquida , Ensaio de Imunoadsorção Enzimática , Espectrometria de Massas por Ionização por Electrospray
4.
Toxicol Rep ; 9: 1130-1138, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36518447

RESUMO

Graphene derivatives are expected to have a great impact in a wide range of applications, among them as food packaging materials. This is one of the sources of potential human oral exposure to them. However, studies devoted to investigating their putative toxic effects at the intestinal level are underrepresented in the scientific literature. Thus, this study aimed to investigate the in vitro toxicity of reduced graphene oxide (rGO) and graphene oxide (GO) in the human intestinal Caco-2 cell line. rGO and GO were firstly characterized and later, cell viability was assessed after exposure to 0-250 µg/mL rGO/GO for 24 and 48 h. Internalization was evidenced for both materials using transmission electron microscopy. A mean effective concentration (24 h) of 176.3 ± 7.6 µg/mL for cytotoxicity was obtained for rGO, whereas GO did not induce any change at the concentration range evaluated. However, both of them altered oxidative stress biomarkers, causing increased reactive oxygen species (ROS) and depletion of the glutathione content (GSH) after exposures up to 24 h. Further studies, particularly with rGO, are required to elucidate their toxicity profile in experimental models relevant for oral exposures.

5.
Food Chem Toxicol ; 146: 111846, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33166674

RESUMO

A biopreservative derived from the fermentation of a dairy byproduct by Enterococcus faecalis UGRA10 strains being developed. This product possesses a strong and wide antibacterial spectrum mainly due to the presence of Enterocin AS-48 in its composition. To assess its potential as food additive, the mutagenicicity and genotoxicity has been assayed by means of the bacterial reverse-mutation assay in Salmonella typhimurium TA97A, TA98, TA100, TA102, TA1535 strains (Ames test, OECD 471, 2020) and the micronucleus test (MN) (OECD 487, 2016) in L5178Y/Tk ± cells. The results in the Ames test after exposure to the byproduct (6.75-100 µg/plate) with absence and presence of the metabolic activation system from rat liver (S9 fraction), revealed not mutagenicity at the conditions tested. For the MN test, the exposition to five enterocin AS-48 concentrations (0.2-1 µg/µl) was tested in the absence and presence of S9 fraction, with no evidence of genotoxicity. Negative results in the mutagenicity and genotoxicity assays point out the good safety profile of the byproduct and support its use as additive. Further toxicological studies are required before its approval and commercial application.


Assuntos
Bacteriocinas/química , Conservantes de Alimentos/química , Conservantes de Alimentos/toxicidade , Animais , Fígado , Testes de Mutagenicidade , Ratos , Salmonella typhimurium
6.
Toxicol In Vitro ; 23(3): 546-53, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19444932

RESUMO

Reduced glutathione (GSH) protects cells against injury by oxidative stress and maintains a range of vital functions. In vitro cell cultures have been used as experimental models to study the role of GSH in chemical toxicity in mammals; however, this approach has been rarely used with fish cells to date. The present study aimed to evaluate sensitivity and specificity of three fluorescent dyes for measuring pro-oxidant-induced changes of GSH contents in fish cell lines: monochlorobimane (mBCl), 5-chloromethylfluorescein diacetate (CMFDA) and 7-amino-4-chloromethylcoumarin (CMAC-blue). Two cell lines were studied, the EPC line established from a skin tumour of carp Cyprinus carpio, and BF-2 cells established from fins of bluegill sunfish Lepomis macrochirus. The cells were exposed for 6 and 24 h to low cytotoxic concentrations of pro-oxidants including hydrogen peroxide, paraquat (PQ), copper and the GSH synthesis inhibitor, L-buthionine-SR-sulfoximine (BSO). The results indicate moderate differences in the GSH response between EPC and BF-2 cells, but distinct differences in the magnitude of the GSH response for the four pro-oxidants. Further, the choice of GSH dye can critically affect the results, with CMFDA appearing to be less specific for GSH than mBCl and CMAC-blue.


Assuntos
Antioxidantes/metabolismo , Células Epiteliais/efeitos dos fármacos , Corantes Fluorescentes/metabolismo , Glutationa/metabolismo , Oxidantes/toxicidade , Animais , Antioxidantes/análise , Butionina Sulfoximina/farmacologia , Carpas , Linhagem Celular Tumoral , Sobrevivência Celular , Sulfato de Cobre/toxicidade , Cumarínicos/química , Cumarínicos/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Fluoresceínas/química , Fluoresceínas/metabolismo , Corantes Fluorescentes/química , Glutationa/análise , Peróxido de Hidrogênio/toxicidade , Paraquat/toxicidade , Perciformes , Valor Preditivo dos Testes , Pirazóis/química , Pirazóis/metabolismo
7.
Arch Environ Contam Toxicol ; 56(1): 52-9, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18392883

RESUMO

The toxicity assessment of chemicals is one of the main issues in the current policies in order to protect the health of the environment and human beings. Food and cosmetic additives have been extensively studied in relation to their toxicity to humans, but data about their ecotoxicological effects are scarce. The aim of this study was to evaluate the toxic effects of the additive 6-methylcoumarine in the aquatic milieu using a test battery comprising experimental model systems from different trophic levels. The inhibition of bioluminiscence was studied in the bacteria Vibrio fischeri (decomposer), the inhibition of growth was evaluated in the alga Chlorella vulgaris (producer) and immobilization was studied in the cladoceran Daphnia magna (first consumer). Finally, several end points were evaluated in the RTG-2 salmonid fish cell line, including neutral red uptake, protein content, methylthiazol tetrazolium salt metabolization, glucose-6-phosphate dehydrogenase activity, lactate dehydrogenase activity and leakage, and morphology. The sensitivity of the test systems employed was as follows: V. fischeri > D. magna > C. vulgaris > RTG-2 cell line. The results show that 6-methylcoumarine is not expected to produce acute toxic effects on the aquatic biota. However, chronic and synergistic effects with other chemicals cannot be excluded and should be further investigated.


Assuntos
Cumarínicos/toxicidade , Poluentes Químicos da Água/toxicidade , Aliivibrio fischeri/efeitos dos fármacos , Aliivibrio fischeri/crescimento & desenvolvimento , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular/citologia , Linhagem Celular/efeitos dos fármacos , Linhagem Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Chlorella vulgaris/efeitos dos fármacos , Chlorella vulgaris/crescimento & desenvolvimento , Cosméticos/efeitos adversos , Daphnia/efeitos dos fármacos , Daphnia/crescimento & desenvolvimento , Relação Dose-Resposta a Droga , Gônadas/efeitos dos fármacos , Gônadas/metabolismo , Gônadas/patologia , Luminescência , Oncorhynchus mykiss , Valor Preditivo dos Testes , Testes de Toxicidade Aguda/métodos
8.
Food Chem Toxicol ; 133: 110810, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31505236

RESUMO

TetraSOD® is a powder of the lyophilized biomass of Tetraselmis chuii strain CCFM03, a marine microalga with a history of use as feed in the aquaculture industry. Recently, algae including T. chuii have been investigated for their potential use in human food. However, published toxicology studies addressing the safety of T. chuii as a food ingredient are not available. To address this issue, the toxicity of TetraSOD® was evaluated using a 90-day oral toxicology study in rats following the Organisation for Economic Co-operation and Development (OECD) test guideline 408. No treatment-related mortality or clinical signs were noted with TetraSOD® at doses of 625, 1667, or 2500 mg/kg/day. Additionally, no adverse effects on haematology, blood biochemistry, organ weights, gross or histopathology were observed. The Non Observed Adverse Effect Level (NOAEL) for TetraSOD® is greater than the highest tested dose of 2500 mg/kg/day.


Assuntos
Biomassa , Alimentos/toxicidade , Microalgas , Animais , Clorófitas , Feminino , Liofilização , Masculino , Nível de Efeito Adverso não Observado , Ratos Sprague-Dawley , Testes de Toxicidade Subcrônica
9.
Sci Total Environ ; 668: 547-565, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-30856566

RESUMO

Microcystins (MCs) and cylindrospermopsin (CYN) are among the most frequent toxins produced by cyanobacteria. These toxic secondary metabolites are classified as hepatotoxins and cytotoxin, respectively. Furthermore, both may present the ability to induce damage to the nervous system. In this sense, there are many studies manifesting the potential of MCs to cause neurotoxicity both in vitro and in vivo, due to their probable capacity to cross the blood-brain-barrier through organic anion transporting polypeptides. Moreover, the presence of MCs has been detected in brain of several experimental models. Among the neurological effects, histopathological brain changes, deregulation of biochemical parameters in brain (production of oxidative stress and inhibition of protein phosphatases) and behavioral alterations have been described. It is noteworthy that minority variants such as MC-LF and -LW have demonstrated to exert higher neurotoxic effects compared to the most studied congener, MC-LR. By contrast, the available studies concerning CYN-neurotoxic effects are very scarce, mostly showing inflammation and apoptosis in neural murine cell lines, oxidative stress, and alteration of the acetylcholinesterase activity in vivo. However, more studies are required in order to clarify the neurotoxic potential of both toxins, as well as their possible contribution to neurodegenerative diseases.


Assuntos
Toxinas Bacterianas/toxicidade , Microcistinas/toxicidade , Sistema Nervoso/efeitos dos fármacos , Uracila/análogos & derivados , Alcaloides , Apoptose , Encéfalo , Cianobactérias , Toxinas de Cianobactérias , Estresse Oxidativo , Uracila/toxicidade
10.
Chemosphere ; 224: 751-764, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30851527

RESUMO

Microcystin-LR (MC-LR) and Cylindrospermopsin (CYN) are produced by cyanobacteria. Although being considered as a hepatotoxin and a cytotoxin, respectively, different studies have revealed neurotoxic properties for both of them. The aim of the present work was to study their cytotoxic effects, alone and in combination, in the SH-SY5Y cell line. In addition, toxicity mechanisms such as oxidative stress and acetylcholinesterase (AChE) activity, and morphological studies were carried out. Results showed a cytotoxic response of the cells after their exposure to 0-100 µg/mL of MC-LR or 0-10 µg/mL CYN in both differentiated and undifferentiated cells. Thus, CYN resulted to be more toxic than MC-LR. Respect to their combination, a higher cytotoxic effect than the toxins alone in the case of undifferentiated cells, and almost a similar response to the presented by MC-LR in differentiated cells were observed. However, after analyzing this data with the isobolograms method, an antagonistic effect was mainly obtained. The oxidative stress study only showed an affectation of glutathione levels at the highest concentrations assayed of MC-LR and the combination in the undifferentiated cells. A significant increase in the AChE activity was observed after exposure to MC-LR in undifferentiated cells, and after exposure to the combination of both cyanotoxins on differentiated cells. However, CYN decreased the AChE activity only on differentiated cultures. Finally, the morphological study revealed different signs of cellular affectation, with apoptotic processes at all the concentrations assayed. Therefore, both cyanotoxins isolated and in combination, have demonstrated to cause neurotoxic effects in the SH-SY5Y cell line.


Assuntos
Toxinas Bacterianas/toxicidade , Microcistinas/toxicidade , Neurotoxinas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Uracila/análogos & derivados , Acetilcolinesterase/metabolismo , Alcaloides , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Toxinas de Cianobactérias , Antagonismo de Drogas , Combinação de Medicamentos , Humanos , Toxinas Marinhas , Neuroblastoma/tratamento farmacológico , Uracila/toxicidade
11.
Toxicon ; 52(1): 1-12, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18588906

RESUMO

The effects of cyanobacterial cells containing microcystins (MCs), toxins from cyanobacteria, on oxidative stress biomarkers from liver and kidney of Tenca fish (Tinca tinca) were investigated under laboratory conditions. Moreover, a histopathological study of liver, kidney, heart and intestine tissues was performed. Fish were orally exposed to cyanobacterial cells dosing 0, 5, 11, 25 and 55 microg MC-LR/fish mixed with the food. Results showed a dose-dependent decrease of superoxide dismutase (SOD) activity, and also of catalase (CAT) in the liver. Glutathione levels and protein oxidation, however, were not altered by the exposure to the cyanobacterial material. The microscopic study revealed tissue alterations even at the lower cyanobacterial cells doses. Onion-like hepatocytes in the liver, glomerulopathy in the kidney, loss of myofibrils in the heart and vacuolated enterocytes in the gastrointestinal tract were the main changes observed. These findings suggest that this fresh water fish can be adversely affected by cyanobacterial blooms in their natural habitats.


Assuntos
Cyprinidae/metabolismo , Microcystis/patogenicidade , Estresse Oxidativo , Administração Oral , Animais , Glutationa/análise , Rim/metabolismo , Rim/patologia , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Tamanho do Órgão , Superóxido Dismutase/metabolismo
12.
Toxicol In Vitro ; 21(8): 1460-7, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17706912

RESUMO

Approximately 80 microcystins (MCs) variants have been isolated in surface water worldwide. The toxicity of the most frequently MCs are encountered, MC-LR and MC-RR, has been extensively studied in humans and animals. However, studies dealing with MC-YR toxicity are still scarce. In this work, the toxic effects of MC-YR were investigated in the fish cell line PLHC-1, derived from a hepatocellular carcinoma of the topminnow Poeciliopsis lucida, and RTG-2 fibroblast-like cells derived from the gonads of rainbow trout Oncorhynchus mykiss. After 48 h, morphological and biochemical changes (total protein content, neutral red uptake and methylthiazol tetrazolium salt metabolization) were determined. The most sensitive endpoint for both cell lines was the reduction of total protein content, with EC(50) values of 35 microM for PLHC-1 cells and 67 microM for the RTG-2 cell line. Lysosomal function and methylthiazol tetrazolium salt metabolization were stimulated at low concentrations, while they decreased at high doses. Increase of piknotic cells, rounding effects, reduction in cell number and cell size, hydropic degeneration, and death mainly by necrosis but also by apoptosis were observed in the morphological study. Furthermore, PLHC-1 cells are more sensitive than RTG-2 cells to MC-YR exposure. These results were similar to those obtained when both cell lines were exposed for 24h to a Microcystis aeruginosa isolated strain extract containing MC-LR.


Assuntos
Peixes , Microcistinas/toxicidade , Animais , Linhagem Celular , Relação Dose-Resposta a Droga , Esquema de Medicação , Proteínas de Peixes/metabolismo
13.
Food Chem Toxicol ; 101: 36-47, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28065759

RESUMO

Oregano essential oil (Origanum vulgare L. virens) (OEO) is being used in the food industry due to its useful properties to develop new active packaging systems. In this concern, the safety assessment of this natural extract is of great interest before being commercialized. The European Food Safety Authority requests different in vivo assays to ensure the safety of food contact materials. One of these studies is a 90 days repeated-dose oral assay in rodents. In the present work, 40 male and 40 female Wistar rats were orally exposed to 50, 100 and 200 mg/kg body weight (b.w.) OEO during 90 days following the OECD guideline 408. Data revealed no mortality and no treatment-related adverse effects of the OEO in food/water consumption, body weight, haematology, biochemistry, necropsy, organ weight and histopathology. These findings suggest that the oral no-observed-adverse-effect level (NOAEL) of this OEO is 200 mg/kg b.w. in Wistar rats, the highest dose tested. In conclusion, the use of this OEO in food packaging appears to be safe based on the lack of toxicity during the subchronic study at doses 330-fold higher than those expected to be in contact consumers in the worst scenario of exposure.


Assuntos
Óleos Voláteis/toxicidade , Origanum/química , Testes de Toxicidade Subcrônica/métodos , Administração Oral , Animais , Peso Corporal/efeitos dos fármacos , Feminino , Masculino , Nível de Efeito Adverso não Observado , Óleos Voláteis/administração & dosagem , Ratos , Ratos Wistar
14.
J Chromatogr A ; 1525: 145-151, 2017 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-29031968

RESUMO

Compound-specific isotope analysis (CSIA) usually requires preparative steps (pretreatments, extraction, derivatization) to get amenable chromatographic analytes from bulk geological, biological or synthetic materials. Analytical pyrolysis (Py-GC/MS) can help to overcome such sample manipulation. This communication describe the results obtained by hyphenating analytical pyrolysis (Py-GC) with carbon isotope-ratio mass spectrometry (IRMS) for the analysis of a polylactic acid (PLA) a based bio-plastic extruded with variable quantities of a natural plant extract or oregano essential oil. The chemical structural information of pyrolysates was first determined by conventional analytical pyrolysis and the measure of δ13C in specific compounds was done by coupling a pyrolysis unit to a gas chromatograph connected to a continuous flow IRMS unit (Py-GC-C-IRMS). Using this Py-CSIA device it was possible to trace natural additives with depleted δ13C values produced by C3 photosystem vegetation (cymene: -26.7‰±2.52; terpinene: -27.1‰±0.13 and carvacrol: -27.5‰±1.80 from oregano and two unknown structures: -23.3‰±3.32 and -24.4‰±1.70 and butyl valerate: -24.1‰±3.55 from Allium spp.), within the naturally isotopically enriched bio-plastic backbone derived from corn (C4 vegetation) starch (cyclopentanones: -14.2‰±2.11; lactide enantiomers: -9.2‰±1.56 and larger polymeric units: -17.2‰±1.71). This is the first application of Py-CSIA to characterize a bio-plastic and is shown as a promising tool to study such materials, providing not only a fingerprinting, but also valuable information about the origin of the materials, allowing the traceability of additives and minimizing sample preparation.


Assuntos
Técnicas de Química Analítica/métodos , Embalagem de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Poliésteres/química , Isótopos de Carbono/análise , Cimenos , Monoterpenos/análise , Óleos Voláteis/análise , Extratos Vegetais/análise , Polímeros/química
15.
Food Chem Toxicol ; 90: 18-29, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26827789

RESUMO

Proallium AP(®) is a commercial Allium extract intended to be used in active food packaging as the antibacterial and antioxidant effects of some organosulfur compounds are well known. However, there is little information on its toxicity and the Scientific Committee on Food (UE) requires the safety assessment of substances used in food contact materials. Thus, the aim of this study was to conduct for the first time a subchronic oral toxicity study of Proallium AP(®) with groups of 10 males and 10 females Sprague-Dawley rats fed a diet containing 0, 25, 100, 400 mg/kg/d for 90 days. No treatment-related clinical signs or mortality were noted. Besides, no treatment-related effects with regard to any of the toxicological biomarkers considered were observed, including biochemical, haematological and histopathology parameters. In conclusion, the non-observed-adverse-effect-level (NOAEL) for Proallium AP(®) in rats was determined to be a dietary dose of 400 mg/kg/d under the present experimental conditions, a value 500-fold higher than the exposure derived from its potential use in active packaging.


Assuntos
Allium/química , Extratos Vegetais/toxicidade , Animais , Relação Dose-Resposta a Droga , Feminino , Embalagem de Alimentos , Masculino , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Ratos , Ratos Sprague-Dawley
16.
Artigo em Inglês | MEDLINE | ID: mdl-27455176

RESUMO

Consumers' concerns about the environment and health have led to the development of new food packaging materials avoiding petroleum-based matrices and synthetic additives. The present study has developed polylactic acid (PLA) films containing different concentrations of essential oil from Origanum vulgare L. virens (OEO). The effectiveness of this new active packaging was checked for use in ready-to-eat salads. A plasticising effect was observed when OEO was incorporated in PLA films. The rest of the mechanical and physical properties of developed films did not show much change when OEO was included in the film. An antioxidant effect was recorded only for films containing the highest percentages of the active agent (5% and 10%). In addition, films exhibited in vitro antibacterial activity against Staphylococcus aureus, Yersinia enterocolitica, Listeria monocytogenes, Enterococcus faecalis and Staphylococcus carnosus. Moreover, in ready-to-eat salads, antimicrobial activity was only observed against yeast and moulds, where 5% and 10% of OEO was the most effective.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Embalagem de Alimentos , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Origanum/química , Poliésteres/química , Antibacterianos/química , Antioxidantes/química , Enterococcus faecalis/efeitos dos fármacos , Listeria monocytogenes/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Poliésteres/farmacologia , Staphylococcus/efeitos dos fármacos , Yersinia enterocolitica/efeitos dos fármacos
17.
Toxicon ; 45(4): 395-402, 2005 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-15733560

RESUMO

The effect of acute exposure of intraperitoneal injection of microcystin-LR (MCLR) on antioxidant enzymes and lipid peroxidation has been studied in liver and kidney of rats. Rats were treated with two doses, i.e. 100 and 150 microg of pure MCLR/kg body weight or saline solution. The enzyme activities of glutathione peroxidase (GSH-Px), glutathione reductase (GR), superoxide dismutase (SOD) and catalase (CAT) in the liver were significantly decreased in MCLR-treated rats. The decrease of GR activity in the liver was 60%, followed by GSH-Px, SOD and CAT. Similarly, a decrease in the antioxidant enzymes was found in the kidney of MCLR-treated rats, such as GSH-Px (27-31%), GR (22%), SOD (42%) and CAT (25-28%). Concomitantly, significant increases in lipid peroxidation levels were recorded in liver (121 and 196% for 100 and 150 microg/kg, respectively) and kidney (48 and 58% for 100 and 150 microg/kg, respectively) from MCLR-treated rats. In conclusion, acute exposure to MCLR results in a decrease in the antioxidant enzymes and an increase in lipid peroxidation in liver and kidney rats, suggesting the oxidative stress as an important role in the pathogenesis of MCLR-induced toxicity. Antioxidant enzymes were significantly consumed in the liver and a minor decrease was found in kidney, confirming the organ-specific effects of MCLR.


Assuntos
Antioxidantes/metabolismo , Rim/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Peptídeos Cíclicos/toxicidade , Análise de Variância , Animais , Catalase/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Rim/enzimologia , Rim/fisiologia , Peroxidação de Lipídeos/fisiologia , Fígado/enzimologia , Fígado/fisiologia , Masculino , Toxinas Marinhas , Microcistinas , Ratos , Ratos Wistar , Espectrofotometria Ultravioleta , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
18.
Toxicol In Vitro ; 19(7): 865-73, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16081241

RESUMO

Cyanobacterial toxins, especially microcystins (MC), are found in eutrophied waters through the world. Acute poisonings of animals and humans has been reported following MC exposure. In the present study, two fish cell lines, PLHC-1 and RTG-2, were evaluated after exposure to the cyanobacterial toxins MC-LR and MC-RR. The effects of different concentrations of the toxins were investigated in both cell lines at morphological and biochemical levels (total protein content, lactate dehydrogenase leakage, lysosomal activity and succinate dehydrogenase activity). The results obtained showed a decrease in protein content and no relevant increase in cell disruption, except for MC-LR in PLHC-1 cells. Morphological changes produced by microcystins were cellular swelling, blebbling, rounding, reduction in the cell number and increase in the number and size of lysosomal bodies. In addition, steatosis was produced in hepatoma PLHC-1 cells, particularly with MC-RR. Furthermore, the fish PLHC-1 cell line was more sensitive than RTG-2 cells to the cyanobacterial toxins compared, being the stimulation of the lysosomal function and the induction of steatosis the most specific changes detected.


Assuntos
Toxinas Bacterianas/toxicidade , Peptídeos Cíclicos/toxicidade , Animais , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cianobactérias , Relação Dose-Resposta a Droga , Peixes , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Toxinas Marinhas , Microcistinas , Coloração e Rotulagem , Succinato Desidrogenase/metabolismo
19.
Food Chem Toxicol ; 86: 365-73, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26607106

RESUMO

Essential oils from onion (Allium cepa L.), garlic (Allium sativum L.), and their main components, such as propyl thiosulfinate oxide (PTSO) are being intended for active packaging with the purpose of maintaining and extending food product quality and shelf life. The present work aims to assess for the first time the potential mutagenicity/genotoxicity of PTSO (0-50 µM) using the following battery of genotoxicity tests: (1) the bacterial reverse-mutation assay in Salmonella typhimurium (Ames test, OECD 471); (2) the micronucleus test (OECD 487) (MN) and (3) the mouse lymphoma thymidine-kinase assay (OECD 476) (MLA) on L5178YTk(+/-), cells; and (4) the comet assay (with and without Endo III and FPG enzymes) on Caco-2 cells. The results revealed that PTSO was not mutagenic in the Ames test, however it was mutagenic in the MLA assay after 24 h of treatment (2.5-20 µM). The parent compound did not induce MN on mammalian cells; however, its metabolites (in the presence S9) produced positive results (from 15 µM). Data from the comet assay indicated that PTSO did not induce DNA breaks or oxidative DNA damage. Further in vivo genotoxicity tests are needed to confirm its safety before it is used as active additive in food packaging.


Assuntos
Allium/química , Extratos Vegetais/farmacologia , Ácidos Sulfínicos/toxicidade , Animais , Células CACO-2 , Linhagem Celular , Ensaio Cometa , Embalagem de Alimentos , Humanos , Camundongos , Testes para Micronúcleos , Mutação , Extratos Vegetais/química , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Ácidos Sulfínicos/química
20.
Talanta ; 45(2): 379-86, 1997 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-18967016

RESUMO

Forty wine vinegar samples from the south of Spain were analyzed for mineral content. Nine metals (As, Ca, Cu, Fe, K, Mg, Mn, Na and Zn) were chosen as chemical features that may account for the rate of the vinegar fermentation process. Pattern recognition techniques were applied for distinguishing quick and slow processed vinegars. The results obtained indicated an excellent performance in both recalling and prediction ability.

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