Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Toxicon ; 202: 27-39, 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34562492

RESUMO

Mycotoxins are secondary metabolites produced by several fungi, mainly from Penicillium, Fusarium, and Aspregillus genera. They can contaminate many raw materials both in the field and during storage under very different conditions. This study aimed to evaluate mycotoxin contamination levels of raw materials and products for animals in Poland in the years 2015-2020. Producers, farmers, and veterinary doctors delivered a total of 3980 samples (642 maize samples, 2027 feed samples, 990 small grain samples, 142 maize silage samples and 179 TMR samples). Samples were analyzed for the occurrence of several mycotoxins, including aflatoxins, fumonisins, ochratoxin A, deoxynivalenol, nivalenol, T-2 toxin, H-2 toxin, and zearalenone. Trichothecenes, zearalenone, and fumonisins were determined using the LC-MS/MS technique. Ochratoxin A and aflatoxins were determined using the HPLC-FLD method. Deoxynivalenol and zearalenone were the most common contamination in maize samples (97.3% and 98.4%, respectively) and feed samples (99.7% and 100% samples, respectively). They were also present in all maize silage and TMR samples. The highest concentration levels of deoxynivalenol and zearalenone were 16,889 µg/kg in the wheat sample and 1420 µg/kg in the maize sample. Additionally, in 51 samples, mycotoxins level (mainly deoxynivalenol and zearalenone levels) was above recommended levels set by the European Union. The present study showed that both feeding and raw materials are contaminated by mycotoxins, often by more than one.


Assuntos
Fumonisinas , Micotoxinas , Animais , Cromatografia Líquida , Contaminação de Alimentos/análise , Micotoxinas/análise , Espectrometria de Massas em Tandem
2.
Org Biomol Chem ; 16(6): 981-987, 2018 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-29344591

RESUMO

Novel chiral macrocyclic polyimines with spiro carbon atoms are described. The key feature of the synthesis is the formation of an axially chiral quaternary carbon atom having four constitutionally identical substituents. This is possible either by the freezing of the labile conformation of a spiro-diboronate moiety or by the diastereomeric fitting of a conformationally stable spiro-acetal moiety into a chiral framework. A general model for the description of this type of axial chirality is proposed.

3.
Chem Zvesti ; 71(6): 1073-1082, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28553006

RESUMO

Mycotoxins and selected hazardous alkaloids in the medicinal plants (Panax ginseng, Angelica sinensis, and Withania somnifera) and dietary supplements were determined. Purine alkaloids were found in majority of samples; however, isoquinoline alkaloids were less abundant than indole. The predominant alkaloids appear to be caffeine (purine group), harman (indole group) and berberine (isoquinoline). Examined medicinal plants and dietary supplements were contaminated by mycotoxins (especially ochratoxin A 1.72-5.83 µg kg-1), and many species of mold (e.g. Cladosporium, Eurotium, Aspergillus, Rhizopus, Penicillium). MTT cytotoxicity tests revealed that plant and supplements extracts exhibited medium or high cytotoxicity (only Dong quai-low). Moreover, antioxidant activity, total phenolics content and selected phytochemicals were analyzed by spectrophotometric and chromatographic methods. Quercetin and rutin were predominant flavonols (1.94-9.51 and 2.20-7.28 mg 100 g-1, respectively). Analysis of phenolic acids revealed-gallic acid, as the most abundant, except Panax ginseng, where ferulic acid was prevailing. The results were analyzed by chemometric methods (cluster analysis, ANOVA).

4.
Artigo em Inglês | MEDLINE | ID: mdl-24919718

RESUMO

In this study moulds and 12 mycotoxins in dry pet food samples (25 for dogs and 24 for cats) were determined. Primary moulds identified were Aspergillus, Mucor and Penicillium, found in 55% of the samples. Deoxynivalenol and zearalenone (ZEN) were detected in all samples with mean respective concentrations being 97.3 and 38.3 µg kg(-1) in cat food and 114 and 20.1 µg kg(-1) in dog food. T-2 and HT-2 toxins were present in 88% and 84% of the samples, respectively. Two samples contained fumonisins, with a maximum concentration of 108 µg kg(-1). Aflatoxin B1 and ochratoxin A were detected in 8% and 45% of the samples, respectively. The measured mould and mycotoxin levels were consistent with results obtained by other studies. However, potential exposure to relatively high concentrations of an oestrogen mycotoxin as is ZEN, especially when in combination with other mycotoxins, needs attention.


Assuntos
Grão Comestível/microbiologia , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Fungos , Micotoxinas/análise , Animais de Estimação , Animais , Aspergillus , Gatos , Cromatografia Líquida/métodos , Cães , Fluorescência , Espectrometria de Massas/métodos , Mucor , Penicillium
5.
Poult Sci ; 91(4): 844-51, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22399723

RESUMO

Recent data suggest that Fusarium trichothecenes may reduce broiler performance at levels previously thought not to affect this variable in chickens. In the present study, we investigated the effects of deoxynivalenol (DON), a type-B trichothecene, on broilers. Male broilers at 7 d of age were fed either a basal diet (0.265 ± 0.048 mg of DON; 0.013 ± 0.001 mg of zearalenone/kg), a low DON diet (1.68 mg of DON/kg; 0.145 ± 0.007 mg of zearalenone/kg), or a high DON diet (12.209 ± 1.149 mg of DON/kg; 1.094 ± 0.244 mg of zearalenone/kg). Increasing levels of DON decreased the weekly weight gain linearly (P ≤ 0.041) during the first 3 wk of exposure; there were no significant differences in the weight gain of the birds after wk 3. With increasing levels of DON, the titers against Newcastle disease virus increased linearly during wk 2 (P = 0.022) and wk 4 (P = 0.033) of exposure, whereas the titers against infectious bronchitis virus decreased linearly (P = 0.006) during wk 5 of exposure. The serum protein concentration increased linearly (P = 0.017) during wk 2 and quadratically (P = 0.002) during wk 4 of exposure. Under these experimental conditions, the performance and vaccine response of the broilers were modulated to varying degrees at concentrations of DON that are currently permitted (up to 5 mg/kg of diet) in many countries. Further studies are therefore required to clarify the implications of these results on the welfare of chickens.


Assuntos
Ração Animal , Galinhas/crescimento & desenvolvimento , Galinhas/imunologia , Contaminação de Alimentos , Micotoxinas/toxicidade , Doenças das Aves Domésticas/imunologia , Tricotecenos/toxicidade , Ração Animal/análise , Ração Animal/microbiologia , Animais , Anticorpos Antivirais/sangue , Proteínas Sanguíneas/análise , Ensaio de Imunoadsorção Enzimática/veterinária , Fusarium/química , Masculino , Micotoxinas/análise , Distribuição Aleatória , Tricotecenos/análise , Vacinas Virais/imunologia
6.
J Anim Physiol Anim Nutr (Berl) ; 96(5): 870-7, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22356129

RESUMO

We performed a 4-year survey (2006-2009, 1255 samples) of fungal secondary metabolites in feed material (cereal and corn grains) and feedstuffs (silages, mixed feeds). Five major mycotoxin groups were studied, including aflatoxins (AF), ochratoxin A (OTA), trichothecenes [deoxynivalenol (DON), nivalenol (NIV), T-2 toxin, HT-2 toxin], zearalenone (ZEA) and fumonisins (FUM). The metabolites were identified using HPLC methods with fluorescent, UV and MS/MS detection. Both immunoaffinity and SPE columns were used for sample preparation. In eleven samples, the concentration of several mycotoxins exceeded the recommended guidelines for feedstuffs. DON was detected at the highest concentration in the majority of analysed samples (cereal grains, silages and mixed feeds, maximum values ranged from 409 to 14,470 ng/g). Corn grains also contained other Fusarium toxins (FUM) at maximum levels ranging from 435 to 9409 ng/g. The highest average(positive) concentration of the other trichothecenes (NIV, T-2 and HT-2 toxins) was <5.0-139 ng/g. ZEA was found at the highest concentration in corn grains and silages (maximum values ranging from 292 to 603 ng/g and 116 to 1150 ng/g, respectively). The highest average(positive) concentration and the maximum level of OTA were detected in cereal grains (33.0 ng/g in 2009 and 760 ng/g in 2007, respectively). Less than 7% of the 557 samples were contaminated with AF at low levels (maximum of 0.61 ng/g). Our results support the need for further monitoring of mycotoxins in Polish feedstuffs and their components.


Assuntos
Ração Animal/análise , Micotoxinas/química , Animais , Polônia , Fatores de Tempo
7.
Adv Med Sci ; 55(2): 242-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20934960

RESUMO

PURPOSE: It is essential in the medical care for immunocompromised patients that the environment should create minimal infection risk. Particularly, it concerns fungal infections. Fungi belonging to the Aspergillus genus are second frequent group of nosocomial pathogens producing opportunistic infections. MATERIAL AND METHODS: The objective of the study was evaluation of prevalence and cytotoxicity of selected Aspergillus strains isolated from the neonatal intensive care unit environment. During 5 consecutive days, 30 samples of indoor air and 120 imprints from the ward environment were collected. Cytotoxicity of 17 strains was evaluated using a MTT (3-(4,5-dimethylthiazol-2-yl) 2,5 diphenyltetrazolium bromide) test. RESULTS: Mean numbers of fungi in the indoor air varied from 50 to 2370 c.f.u.xm-3 while in the imprints from 0.04 to 8.83 c.f.u.xcm-2. Moulds were isolated from most of the materials. All of the 17 strains subject to MTT test were cytotoxic. CONCLUSION: All of the Aspergillus strains isolated from the neonatal intensive care unit were cytotoxic. Cytotoxic Aspergillus strains present in the environment of immunocompromised patients may be potentially dangerous to them.


Assuntos
Microbiologia do Ar , Aspergillus/isolamento & purificação , Unidades de Terapia Intensiva Neonatal , Cladosporium/isolamento & purificação , Humanos , Recém-Nascido , Penicillium/isolamento & purificação , Sais de Tetrazólio
8.
Mycotoxin Res ; 24(3): 140-50, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23604749

RESUMO

Mucorales are regarded as the aetiological agents of Mucormycosis. Their capabilities to produce mycotoxins are not profoundly investigated, in contrast to those of the fungi from the generaPenicillium, Aspergillus, orFusarium. The aim of this study was to isolate and identify fungi of the order Mucorales and investigate mycotoxins production. Twelve samples of visibly moulded grass silage and eight samples of damaged whole crop maize silage were analysed. Malt extract agar plates were used for sub cultivation. Three fungal species of the order Mucorales were isolated from grass silage, which were identified by their macro-and micro-morphology asAbsidia corymbifera, Mucor circinelloides andRhizopus stolonifer. The cytotoxicity ofMucor circinelloides extract was analysed using the cytotoxicity test (MTT assay) and the result, showed a low cytotoxicity. Additionally extracts fromAbsidia corymbifera, Mucor circinelloides andRhizopus stolonifer were tested for mycotoxin-production using an LC/MS/MS-based multimycotoxin method. 3-nitropropionic acid was detected in the culture extract ofMucor circinelloides.

9.
Mycotoxin Res ; 23(1): 22-6, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23605812

RESUMO

Ochratoxin A (OTA) was analyzed in human serum and kidney samples, collected in Poland in the Pomeranian region from March to September 2005. OTA was determined using reversed phase liquid chromatography with fluorescence detection. The collected samples were from patients after nephrectomy (9 from men and 11 from women) and control serum samples from people without kidney diseases (3 and 3, respectively). The mean concentration OTA in serum of the healthy group was 0.37 ng/ml in both men and women. In patients subjected to nephrectomy it reached 1.06 ng/ml in men and 0.94 ng/ml in women, the mean content of ochratoxin A in kidneys was 0.23 ng/g and 0.20 ng/g, respectively. The highest concentration of OTA in serum among the patients subjected to nephrectomy was 3.77 ng/ml in men and 2.27 ng/ml in women while in kidneys 0.45 ng/g and 0.39 ng/g, respectively.

10.
Org Lett ; 5(18): 3301-3, 2003 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-12943412

RESUMO

[reaction: see text] Achiral molecules or ions can display induced circular dichroism (ICD) within their absorption bands on association with chiral inducing molecules. The reverse process is equally important, although less appreciated: chiral inducing molecules, such as tartrates, can show significantly differing CD bands in different achiral environments. Therefore true ICD due to achiral molecules can only be demonstrated in the spectral region outside the absorption bands of the chiral inducing molecules. The case of tartrate-trisimidazoline helical assembly in aqueous solvent is discussed.

11.
Mycotoxin Res ; 18 Suppl 2: 142-4, 2002 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-23606150

RESUMO

Growing consumption of beer in present diet may lead to higher risk of piling up of ochratoxin A. In our studies we evaluated malt and beer from the local Pomeranian brewery which offers its products at the market in the lowest price. The evaluation had been conducted for 3 months during winter time and the content of fungi, OTA and ergosterol had been analyzed.High concentration of ergosterol was found in all the malt samples, whereas ochratoxin A was present in one delivery of the product only. In contrast, in 70% beer samples low concentration of OTA was found.

12.
J Anim Physiol Anim Nutr (Berl) ; 85(7-8): 212-6, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11686791

RESUMO

The occurrence of ochratoxin A (OTA) in canned (26 samples) as well as dry pet foods (17 samples) for cats and dogs was investigated. In addition, 26 feline kidney samples with or without kidney alterations were surveyed for OTA-residues. The separation and detection of OTA was carried out by an isocratic high-performance liquid chromatography system based on reversed phase with fluorescence detection. After homogenization and extraction steps, immuno-affinity columns were applied for sample clean up. OTA could be detected in 47% (n=40) of the pet food samples. Those found positive contained generally low amounts of OTA (0.1-0.8 microg/kg original substance). Higher levels were only detected in two pet food samples (3.2 and 13.1 microg/kg toxin, respectively). Low concentrations of ochratoxin A could also be found iIn tissue of cat kidneys, with 16 of the analysed kidneys (n=26) being positive. The concentration levels were between 0.35 and 1.5 microg/kg OTA in tissue. No relation between pathological findings and ochratoxin levels in feline kidneys could be assessed.


Assuntos
Ração Animal/análise , Carcinógenos/análise , Gatos/metabolismo , Cães/metabolismo , Rim/química , Ocratoxinas/análise , Animais , Cromatografia Líquida de Alta Pressão/veterinária , Fluorescência , Contaminação de Alimentos/análise , Rim/patologia
13.
Mycotoxin Res ; 17 Suppl 2: 137-41, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23605858

RESUMO

The studies focused on the effect of 1-ppm ochratoxin A solution on the activity of some enzymes during successive embryogenesis stages ofAscaris suum. As a result of OTA-affected incubation ofA suum eggs, inhibition of AcP reactions was observed throughout the embryonic development, reduction in of SDH and LDH activity during cleavage and gastrulation, and enhancement of the SDH and LDH activity was found in larvae. Moreover, inhibition of the processes of cleavage, gastrulation and organogenesis was recorded. The observed morphological and metabolic embryo disorders demonstrated teratogenic properties of the studied mycotoxin, and the presence of granules of various sizes in the developing eggs may indicate that OTA penetrated into the eggs.

14.
Mycotoxin Res ; 17 Suppl 2: 229-33, 2001 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-23605878

RESUMO

In 1997, large areas in South Poland were affected by a flood of the River Oder. As a immediate measure to support shelterless people living in these areas, simple pavillons were built, which two years later had to be evacuated because of high contamination with moulds. The rate of mould contamination on the walls in interior microclimate and the occurrence of OTA was estimated in two of these pavillions. The air-flow and the moisture were regulated in the experimental rooms where wallpaper was used as the research material. The gypsum cardboards on the walls were also observed. It was found that the moulds were of different species and the number of them was constantly changing irrespective of the accepted configuration of the research position. In every single wallpaper sample OTA was detected. The greatest amount of OTA was found in the pavillions with humidified air. The test of gipsum cardboard walls in pavilions chosen at random, showed an enormous amount of moulds. However, the OTA was not detected.

15.
Mycotoxin Res ; 16 Suppl 1: 70-4, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23605419

RESUMO

In vitro biodegradation experiments were done using some probiotic microorganisms. DifferentSaccharomyces cerevisiae, Lactobacilli andBacilli strains were tested for their ability to degrade Nivalenol (NIV), Deoxynivalenol (DON), Diacetoxyscirpenol (DAS), T2-Toxin and Ochratoxin A (OTA). The concentrations of selected mycotoxins were in the range of natural occurring toxin contaminations (1ppm for NIV and DON, 500ppb for DAS and T-2 and 50ppb for OTA). No alteration of concentrations could be registered for the tested trichothecenes. The best results could be achieved in experiments with OTA by up to 94% detoxification. Influence of toxins on colony forming unit of all tested microorganisms were recorded. Especially T-2 toxin and DAS have a slowing effect on growth of some strains.

16.
Mycotoxin Res ; 16 Suppl 2: 208-12, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23605533

RESUMO

Effects of high and low dose of ochratoxin A (OTA) as pure toxin supplemented to feed were investigated on the performance of growing chicken. Two groups were fed with different doses of chemical pure OTA 0.5 ppm and 5 ppm in feed and the effects of toxin on body and organ weights were studied and compared with control group. No effects were observed by feeding 0.5 ppm OTA, whereas 5 ppm had a negative effect on the daily body mass gain. OTA in feed had a negative effect on the daily body mass gain. In contrary nephrotoxic effects could be observed by feeding the naturally OTA contaminated feed with only 0.2 ppm of OTA produced byPenicillium verrucosum.

17.
Mycotoxin Res ; 7 Suppl 1: 8-11, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23605730

RESUMO

The effect of dietary fibre on zearalenone absorption, metabolic pathway and urinary excretion was investigated in a prepubertal gilt. Levels of zearalenone and metabolites were measured in the portal vein, in the carotid artery and in urine after feeding one portion of a standard diet or a high fibre diet (85 % standard diet + 15 % oat husks), both containing 5 ppm zearalenone. Independently of diet, the levels of zearalenone in the portal vein were higher than in the carotid artery during the following 48 hrs. Regarding the metabolite α-zearalenol, strikingly lower systemic levels were observed when high fibre diet was fed to the animal. The decrease of α-zearalenol level, due to high fibre diet, was also reflected in urine. The total amount of zearalenone and α-zearalenol excreted in urine, during 24 hours after feeding, was about 9 % of the zearalenone intake, independently of diet. Almost all zearalenone and α-zearalenol were found conjugated with glucuronic acid in both plasma and urine.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...