The Experts below are selected from a list of 291 Experts worldwide ranked by ideXlab platform
Xiaodong Zheng - One of the best experts on this subject based on the ideXlab platform.
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Detoxification of mycotoxin patulin by the yeast Rhodosporidium paludigenum.
Food chemistry, 2015Co-Authors: Ruiyu Zhu, Kirstin Feussner, Fujie Yan, Petr Karlovsky, Xiaodong ZhengAbstract:Patulin is a mycotoxin produced by Penicillium species which often contaminates fruit and fruit-derived products. In this work the degradation of patulin by the yeast Rhodosporidium paludigenum was studied and the toxicity of the degradation product was determined. Patulin-degrading activity of R. paludigenum was inducible by patulin; it was located within yeast cells and the enzyme did not require a dissociable cofactor. Chromatographic behavior and molecular mass of the degradation product indicated that R. paludigenum transformed patulin into desoxypatulinic acid. The degradation product was significantly less toxic to Arabidopsis thaliana and human liver cells than patulin; it was not toxic to Escherichia coli at the highest concentration tested. The detoxification activity of R. paludigenum toward patulin is a promising tool for the control of patulin contamination in food and feed.
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effect of the yeast rhodosporidium paludigenum on postharvest decay and patulin accumulation in apples and pears
Journal of Food Protection, 2015Co-Authors: Ruiyu Zhu, Xiaodong Zheng, Shuanghuan Guo, Petr KarlovskyAbstract:The effect of a strain of marine yeast Rhodosporidium paludigenum on postharvest blue mold and patulin accumulation in apples and pears stored at 23°C was evaluated. The occurrence and severity of apple and pear decay caused by Penicillium expansum were significantly inhibited by R. paludigenum. However, the application of the yeast at a high concentration (10(8) cells per ml) enhanced patulin accumulation after 7 days of storage; the amount of patulin increased 24.2 times and 12.6 times compared to the controls in infected apples and pears, respectively. However, R. paludigenum reduced the patulin concentration in the growth medium by both biological degradation and physical adsorption. Optimal in vitro patulin reduction was observed at 30°C and at pH 6.0. R. paludigenum incubated at 28°C was tolerant to patulin at concentrations up to 100 mg/liter. In conclusion, R. paludigenum was able to control postharvest decay in apples and pears and to remove patulin in vitro effectively. However, because the yeast induced patulin accumulation in fruit, the assessment of mycotoxin content after biological treatments in postharvest decay control is important. R. paludigenum may also be a promising source of gene(s) and enzyme(s) for patulin degradation and may be a tool to decrease patulin contamination in commercial fruit-derived products.
Petr Karlovsky - One of the best experts on this subject based on the ideXlab platform.
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Detoxification of mycotoxin patulin by the yeast Rhodosporidium paludigenum.
Food chemistry, 2015Co-Authors: Ruiyu Zhu, Kirstin Feussner, Fujie Yan, Petr Karlovsky, Xiaodong ZhengAbstract:Patulin is a mycotoxin produced by Penicillium species which often contaminates fruit and fruit-derived products. In this work the degradation of patulin by the yeast Rhodosporidium paludigenum was studied and the toxicity of the degradation product was determined. Patulin-degrading activity of R. paludigenum was inducible by patulin; it was located within yeast cells and the enzyme did not require a dissociable cofactor. Chromatographic behavior and molecular mass of the degradation product indicated that R. paludigenum transformed patulin into desoxypatulinic acid. The degradation product was significantly less toxic to Arabidopsis thaliana and human liver cells than patulin; it was not toxic to Escherichia coli at the highest concentration tested. The detoxification activity of R. paludigenum toward patulin is a promising tool for the control of patulin contamination in food and feed.
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effect of the yeast rhodosporidium paludigenum on postharvest decay and patulin accumulation in apples and pears
Journal of Food Protection, 2015Co-Authors: Ruiyu Zhu, Xiaodong Zheng, Shuanghuan Guo, Petr KarlovskyAbstract:The effect of a strain of marine yeast Rhodosporidium paludigenum on postharvest blue mold and patulin accumulation in apples and pears stored at 23°C was evaluated. The occurrence and severity of apple and pear decay caused by Penicillium expansum were significantly inhibited by R. paludigenum. However, the application of the yeast at a high concentration (10(8) cells per ml) enhanced patulin accumulation after 7 days of storage; the amount of patulin increased 24.2 times and 12.6 times compared to the controls in infected apples and pears, respectively. However, R. paludigenum reduced the patulin concentration in the growth medium by both biological degradation and physical adsorption. Optimal in vitro patulin reduction was observed at 30°C and at pH 6.0. R. paludigenum incubated at 28°C was tolerant to patulin at concentrations up to 100 mg/liter. In conclusion, R. paludigenum was able to control postharvest decay in apples and pears and to remove patulin in vitro effectively. However, because the yeast induced patulin accumulation in fruit, the assessment of mycotoxin content after biological treatments in postharvest decay control is important. R. paludigenum may also be a promising source of gene(s) and enzyme(s) for patulin degradation and may be a tool to decrease patulin contamination in commercial fruit-derived products.
Ruiyu Zhu - One of the best experts on this subject based on the ideXlab platform.
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Detoxification of mycotoxin patulin by the yeast Rhodosporidium paludigenum.
Food chemistry, 2015Co-Authors: Ruiyu Zhu, Kirstin Feussner, Fujie Yan, Petr Karlovsky, Xiaodong ZhengAbstract:Patulin is a mycotoxin produced by Penicillium species which often contaminates fruit and fruit-derived products. In this work the degradation of patulin by the yeast Rhodosporidium paludigenum was studied and the toxicity of the degradation product was determined. Patulin-degrading activity of R. paludigenum was inducible by patulin; it was located within yeast cells and the enzyme did not require a dissociable cofactor. Chromatographic behavior and molecular mass of the degradation product indicated that R. paludigenum transformed patulin into desoxypatulinic acid. The degradation product was significantly less toxic to Arabidopsis thaliana and human liver cells than patulin; it was not toxic to Escherichia coli at the highest concentration tested. The detoxification activity of R. paludigenum toward patulin is a promising tool for the control of patulin contamination in food and feed.
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effect of the yeast rhodosporidium paludigenum on postharvest decay and patulin accumulation in apples and pears
Journal of Food Protection, 2015Co-Authors: Ruiyu Zhu, Xiaodong Zheng, Shuanghuan Guo, Petr KarlovskyAbstract:The effect of a strain of marine yeast Rhodosporidium paludigenum on postharvest blue mold and patulin accumulation in apples and pears stored at 23°C was evaluated. The occurrence and severity of apple and pear decay caused by Penicillium expansum were significantly inhibited by R. paludigenum. However, the application of the yeast at a high concentration (10(8) cells per ml) enhanced patulin accumulation after 7 days of storage; the amount of patulin increased 24.2 times and 12.6 times compared to the controls in infected apples and pears, respectively. However, R. paludigenum reduced the patulin concentration in the growth medium by both biological degradation and physical adsorption. Optimal in vitro patulin reduction was observed at 30°C and at pH 6.0. R. paludigenum incubated at 28°C was tolerant to patulin at concentrations up to 100 mg/liter. In conclusion, R. paludigenum was able to control postharvest decay in apples and pears and to remove patulin in vitro effectively. However, because the yeast induced patulin accumulation in fruit, the assessment of mycotoxin content after biological treatments in postharvest decay control is important. R. paludigenum may also be a promising source of gene(s) and enzyme(s) for patulin degradation and may be a tool to decrease patulin contamination in commercial fruit-derived products.
Hui Tang - One of the best experts on this subject based on the ideXlab platform.
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Biodegradation of the mycotoxin patulin in apple juice by Orotate phosphoribosyltransferase from Rhodotorula mucilaginosa
Food Control, 2019Co-Authors: Hui Tang, Fang Zhang, Xiaohong Li, Xianghong MengAbstract:Abstract Patulin is a mycotoxin produced by Penicillium species, which causes severe food safety issues throughout the apple industry. The study was focused to investigate the degradation of patulin in apple juice by Orotate phosphoribosyltransferase, separated from Rhodotorula mucilaginosa (R. mucilaginosa). Both optimal degradation conditions and physicochemical characteristics changes were evaluated between before and after patulin degradation in apple juice. The research showed that the optimal degradation conditions were 25 °C for 18 h, adding 0.15 g/L Orotate phosphoribosyltransferase and degraded 1 mg/L patulin. Moreover, after the degradation of patulin, there was no significant difference arised in quality of apple juice and the final patulin degradation effect was over 80% (1 mg/L). Meanwhile, under the condition of 25 °C, pH 3.67, the Vmax, Km and Kcat of Orotate phosphoribosyltransferase were 0.76 μM/h, 16.2 μM and 3.44 × 10−5 S−1, respectively. It will be a promising material for the control of patulin in apple juice.
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Detoxification of mycotoxin patulin by the yeast Rhodotorula mucilaginosa
Food Control, 2019Co-Authors: Hui Tang, Xianghong Meng, Chao Yang, Bingjie LiuAbstract:Abstract Patulin is a kind of mycotoxin, which occurs in food industry frequently and constitutes serious threats to human health. In this work, a strain of yeast with patulin degradation was screened, and identified as Rhodotorula mucilaginosa (R. mucilaginosa JM19) by 26S rDNA D1/D2 region gene sequencing. Subsequently, the patulin detoxification process was analyzed by HPLC-UV. The results showed that patulin was degraded into desoxypatulinic acid by R. mucilaginosa JM19. In addition, patulin degrading capacity of R. mucilaginosa JM19 was strongly dependent on temperature, cell density and initial patulin concentration. Up to 90% of patulin was significantly reduced after 21 h in MES buffer at 35 °C when cell density of yeast was above 1 × 108 cells/L. The R. mucilaginosa JM19 is capable of detoxifying over 50% of initial patulin concentration at 100 μg/mL. The detoxification activity of R. mucilaginosa JM19 toward patulin would be a potential approach for the control of patulin contamination in food and raw materials.
Celia Maria De ,sylos - One of the best experts on this subject based on the ideXlab platform.
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Avaliação dos metodos de determinação e incidencia de aflatoxina M1, patulina e acido ciclopiazonico em alguns alimentos brasileiros
[s.n.], 2018Co-Authors: Celia Maria De ,sylosAbstract:Orientador: Delia Rodriguez- AmayaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de AlimentosResumo: Avaliou-se os métodos analíticos e a incidência de aflatoxina, patulina e ácido ciclopiazônico em produtos alimentícios comercializados na cidade de Campinas. Varias tentativas foram realizadas para a escolha do solvente extratante e da melhor técnica para remover os interferentes das amostras de leite e derivados para determinação de aflatoxina M1. Na extração foram utilizados acetona, metanol e clorofórmio puros, misturados entre si ou com água. Precipitação com sais de metais pesados, partição entre solventes imiscíveis e colunas cromatográficas foram avaliados para promover a limpeza do extrato. A utilização de metais pesados não foi eficiente para eliminar os interferentes. O uso conjunto de clorofórmio e uma coluna cromatográfica demonstrou ser a maneira mais eficiente de extrair a aflatoxina e remover substâncias interferentes. Colunas cromatográficas de sílica e sílica-C18 presentaram melhores resultados que a coluna de celulose. A cromatografia líquida de alta eficiência dos derivados com ácido trifluoroacético e detecção por fluorescência apresentou sensibilidade e especificidade bem maior que o método por cromatografia em camada delgada com quantificação visual da intensidade de fluorescência para determinação de aflatoxina M1. Duzentas e quatro amostras de leite pasteurizado (103), leite em pó (35), queijos (36) e iogurte (30) coletadas durante os anos de 1989/90 e de 1992 foram analisadas. A aflatoxina M1 foi encontrada em apenas quatro amostras de leite pasteurizado com níveis de 73 a 370 ng/L em 1992, ano em que as análises foram realizadas por cromatografia líquida de alta eficiência. Três métodos foram avaliados para a determinação de patulina: os da AOAC (1990), de SIRIWARDANA & LAFONT (1979b) e de MOLLER & JOSEFSSON (1980). A quantificação foi realizada por cromatografia líquida de alta eficiência, inclusive para os dois primeiros métodos nos quais a técnica especificada era cromatografia em camada delgada. O método de MOLLER & JOSEFSSON foi o que apresentou melhores porcentagens de recuperação e um extrato mais limpo, resultando um cromatograma cujo pico da patulina apareceu livre de interferentes. Sessenta e cinco amostras de sucos de frutas (maçã (20), uva (17) , abacaxi (10), goiaba (6) , manga (6) , mamão (3) e banana (3)) e 24 amostras de frutas (maçã (15), mamão (6) e manga (3)) foram analisadas e apenas uma de suco de maçã estava contaminada por patulina com 17 µg/L. Seis amostras de maçã deteriorada foram também analisadas e todas continham patulina em níveis que variaram de 150 a 340 µg/ kg. Foi investigada também a ocorrência simultânea de ácido ciclopiazônico e aflatoxinas B e G em amostras de amendoim, milho e seus derivados, utilizando o método de URANO et all (1992a) e de SOARES & RODRIGUEZ-AMAYA (1989), respectivamente. Em 28 amostras de amendoim e derivados, a presença de ácido ciclopiazônico foi constatada em 4 amostras de amendoim cru, com níveis de 150 a 369 µg/kg. As aflatoxinas foram encontradas em 11 amostras de amendoim cru, amendoim torrado salgado e paçoca com teores de 8 a 340 µg/kg (aflatoxinas totais). As duas toxinas ocorreram simultaneamente em três amostras de amendoim cru. Tanto ácido ciclopiazônico como as aflatoxinas não foram detectados em 25 amostras de milho e derivados (milho de pipoca, farinha de milho e fubá). Os resultados demonstram que a contaminação de leite e derivados por aflatoxina M1 e de frutas e sucos de frutas por patulina não constitui um problema de saúde pública na cidade de Campinas. Por outro lado, a ocorrência de ácido ciclopiazônico agrava ainda mais a situação do amendoim e seus derivados que são largamente contaminados por aflatoxinas B e G. Estas duas também não são problemáticas em milho e derivadosAbstract: In Brazil there is a paucity of information in relation to the mycotoxins aflatoxin M1, patulin and cyclopiazonic acid. Thus, these mycotoxins were investigated in terms of the analytical methods used for their determination and of their incidence in food products commercialized in Campinas. Various trials were carried out to choose the extracting solvent and the best technique for removing interfering substances from samples of milk and dairy products for the determination of aflatoxin Ml. For extraction acetone, methanol and chloroform were utilized either singly, in combination with each other or with water. Precipitation with heavy metal salts, partition between immiscible solvents and conventional column chromatography were evaluated for clean-up. Heavy metals by themselves were not effective in eliminating interfering substances. The combined use of chloroform and a chromatographic column proved to be the most efficient procedure for extraction and clean-up. Columns packed with silica or silica-C18 gave better results than those of cellulose. High performance liquid chromatography of trifluoroacetic acid derivatives and using fluorescence detection, presented much higher sensitivity and specificity than thin layer chromatography with visual quantification of the fluorescence intensity for aflatoxin M1 determination. Two hundred and four samples of milk (103), powdered milk (35) , cheese (36) and yoghurt (30), collected in 1989/90 and in 1992, were analyzed. Aflatoxin M, was found in only 4 samples of milk at 73 to 370 ug/L in 1992, the year when the analyses were carried out by high performance liquid chromatography. Three methods for the determination of patulin were evaluated: those of the AOAC (1990), SIRIWARDANA & LAFONT (1979b) and MOLLER & JOSEFSSON (1980). Quantification was performed by high performance liquid chromatography, even for the first two methods where thin layer chromatography was the specified technique. The method of MOLLER & JOSEFSSON presented higher recovery perceriteges and resulted in a clean extract, giving chromatograms with the patulin peak free of interferences. Sixty-five samples of fruit juices (apple (20), grape (17), pineapple (10), guava (6), mango (6), papaya (3) and banana (3)) and 24 samples of fruits (apple (15), papaya (6) and mango (3)) were analyzed and only one sample of apple juice had patulin at 17 ug/L. Six samples of spoiled apple were also submitted to analysis, all of which were contaminated with patulin at 150 to 340 ug/ kg. The co-occurrence of cyclopiazonic acid and aflatoxins B and G in peanuts, corn and their products was also investigated, using the methods of URANO et alii (1992) and SOARES & RODRIGUEZ-AMAYA (1989) , respectively. Of 28 samples of peanuts and peanut products, cyclopiazonic acid was encountered in 4 samples of raw peanuts at 150 to 369 ug/ kg. Aflatoxins were found in 11 samples of raw peanuts, roasted salted peanuts and ground peanut bar at 8 to 340 ug/kg (total aflatoxins). The two toxins co-existed in 3 samples. Cyclopiazonic acid and aflatoxins were not detected in 25 samples of corn (popcorn, corn flour and grits). The results show that contamination of milk and dairy products with aflatoxin M1 and of fruits and fruit juices with patulin does not constitute a public health problem in the city of Campinas. On the other hand, the occurrence of cyclopiazonic acid can aggravate the situation of peanuts and peanut products, already shown to be highly contaminated with aflatoxins B and G. These two toxins are not problematic in corn and corn productsDoutoradoDoutor em Ciência de Alimento
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Avaliação dos metodos de determinação e incidencia de aflatoxina M1, patulina e acido ciclopiazonico em alguns alimentos brasileiros
2017Co-Authors: Celia Maria De ,sylosAbstract:Resumo: Avaliou-se os métodos analíticos e a incidência de aflatoxina, patulina e ácido ciclopiazônico em produtos alimentícios comercializados na cidade de Campinas. Varias tentativas foram realizadas para a escolha do solvente extratante e da melhor técnica para remover os interferentes das amostras de leite e derivados para determinação de aflatoxina M1. Na extração foram utilizados acetona, metanol e clorofórmio puros, misturados entre si ou com água. Precipitação com sais de metais pesados, partição entre solventes imiscíveis e colunas cromatográficas foram avaliados para promover a limpeza do extrato. A utilização de metais pesados não foi eficiente para eliminar os interferentes. O uso conjunto de clorofórmio e uma coluna cromatográfica demonstrou ser a maneira mais eficiente de extrair a aflatoxina e remover substâncias interferentes. Colunas cromatográficas de sílica e sílica-C18 presentaram melhores resultados que a coluna de celulose. A cromatografia líquida de alta eficiência dos derivados com ácido trifluoroacético e detecção por fluorescência apresentou sensibilidade e especificidade bem maior que o método por cromatografia em camada delgada com quantificação visual da intensidade de fluorescência para determinação de aflatoxina M1. Duzentas e quatro amostras de leite pasteurizado (103), leite em pó (35), queijos (36) e iogurte (30) coletadas durante os anos de 1989/90 e de 1992 foram analisadas. A aflatoxina M1 foi encontrada em apenas quatro amostras de leite pasteurizado com níveis de 73 a 370 ng/L em 1992, ano em que as análises foram realizadas por cromatografia líquida de alta eficiência. Três métodos foram avaliados para a determinação de patulina: os da AOAC (1990), de SIRIWARDANA & LAFONT (1979b) e de MOLLER & JOSEFSSON (1980). A quantificação foi realizada por cromatografia líquida de alta eficiência, inclusive para os dois primeiros métodos nos quais a técnica especificada era cromatografia em camada delgada. O método de MOLLER & JOSEFSSON foi o que apresentou melhores porcentagens de recuperação e um extrato mais limpo, resultando um cromatograma cujo pico da patulina apareceu livre de interferentes. Sessenta e cinco amostras de sucos de frutas (maçã (20), uva (17) , abacaxi (10), goiaba (6) , manga (6) , mamão (3) e banana (3)) e 24 amostras de frutas (maçã (15), mamão (6) e manga (3)) foram analisadas e apenas uma de suco de maçã estava contaminada por patulina com 17 µg/L. Seis amostras de maçã deteriorada foram também analisadas e todas continham patulina em níveis que variaram de 150 a 340 µg/ kg. Foi investigada também a ocorrência simultânea de ácido ciclopiazônico e aflatoxinas B e G em amostras de amendoim, milho e seus derivados, utilizando o método de URANO et all (1992a) e de SOARES & RODRIGUEZ-AMAYA (1989), respectivamente. Em 28 amostras de amendoim e derivados, a presença de ácido ciclopiazônico foi constatada em 4 amostras de amendoim cru, com níveis de 150 a 369 µg/kg. As aflatoxinas foram encontradas em 11 amostras de amendoim cru, amendoim torrado salgado e paçoca com teores de 8 a 340 µg/kg (aflatoxinas totais). As duas toxinas ocorreram simultaneamente em três amostras de amendoim cru. Tanto ácido ciclopiazônico como as aflatoxinas não foram detectados em 25 amostras de milho e derivados (milho de pipoca, farinha de milho e fubá). Os resultados demonstram que a contaminação de leite e derivados por aflatoxina M1 e de frutas e sucos de frutas por patulina não constitui um problema de saúde pública na cidade de Campinas. Por outro lado, a ocorrência de ácido ciclopiazônico agrava ainda mais a situação do amendoim e seus derivados que são largamente contaminados por aflatoxinas B e G. Estas duas também não são problemáticas em milho e derivadosAbstract:In Brazil there is a paucity of information in relation to the mycotoxins aflatoxin M1, patulin and cyclopiazonic acid. Thus, these mycotoxins were investigated in terms of the analytical methods used for their determination and of their incidence in food products commercialized in Campinas. Various trials were carried out to choose the extracting solvent and the best technique for removing interfering substances from samples of milk and dairy products for the determination of aflatoxin Ml. For extraction acetone, methanol and chloroform were utilized either singly, in combination with each other or with water. Precipitation with heavy metal salts, partition between immiscible solvents and conventional column chromatography were evaluated for clean-up. Heavy metals by themselves were not effective in eliminating interfering substances. The combined use of chloroform and a chromatographic column proved to be the most efficient procedure for extraction and clean-up. Columns packed with silica or silica-C18 gave better results than those of cellulose. High performance liquid chromatography of trifluoroacetic acid derivatives and using fluorescence detection, presented much higher sensitivity and specificity than thin layer chromatography with visual quantification of the fluorescence intensity for aflatoxin M1 determination. Two hundred and four samples of milk (103), powdered milk (35) , cheese (36) and yoghurt (30), collected in 1989/90 and in 1992, were analyzed. Aflatoxin M, was found in only 4 samples of milk at 73 to 370 ug/L in 1992, the year when the analyses were carried out by high performance liquid chromatography. Three methods for the determination of patulin were evaluated: those of the AOAC (1990), SIRIWARDANA & LAFONT (1979b) and MOLLER & JOSEFSSON (1980). Quantification was performed by high performance liquid chromatography, even for the first two methods where thin layer chromatography was the specified technique. The method of MOLLER & JOSEFSSON presented higher recovery perceriteges and resulted in a clean extract, giving chromatograms with the patulin peak free of interferences. Sixty-five samples of fruit juices (apple (20), grape (17), pineapple (10), guava (6), mango (6), papaya (3) and banana (3)) and 24 samples of fruits (apple (15), papaya (6) and mango (3)) were analyzed and only one sample of apple juice had patulin at 17 ug/L. Six samples of spoiled apple were also submitted to analysis, all of which were contaminated with patulin at 150 to 340 ug/ kg. The co-occurrence of cyclopiazonic acid and aflatoxins B and G in peanuts, corn and their products was also investigated, using the methods of URANO et alii (1992) and SOARES & RODRIGUEZ-AMAYA (1989) , respectively. Of 28 samples of peanuts and peanut products, cyclopiazonic acid was encountered in 4 samples of raw peanuts at 150 to 369 ug/ kg. Aflatoxins were found in 11 samples of raw peanuts, roasted salted peanuts and ground peanut bar at 8 to 340 ug/kg (total aflatoxins). The two toxins co-existed in 3 samples. Cyclopiazonic acid and aflatoxins were not detected in 25 samples of corn (popcorn, corn flour and grits). The results show that contamination of milk and dairy products with aflatoxin M1 and of fruits and fruit juices with patulin does not constitute a public health problem in the city of Campinas. On the other hand, the occurrence of cyclopiazonic acid can aggravate the situation of peanuts and peanut products, already shown to be highly contaminated with aflatoxins B and G. These two toxins are not problematic in corn and corn product