Peroxidase is an enzyme in the group of oxidoreductases that is widely distributed in nature. It ... more Peroxidase is an enzyme in the group of oxidoreductases that is widely distributed in nature. It can catalyze the oxidation of various organic and inorganic substrates by reacting with hydrogen peroxide and similar molecules. Due to its wide catalytic activity, peroxidases can act in the removal of both phenolic compounds and peroxides, in chemical synthesis and, according to recent studies, in mycotoxin degradation. Therefore, this study aimed at introducing an overview of the mechanism of peroxidase action, extraction sources, mycotoxin degradation capacity and other potential applications in the food industry.
Environmental Science and Pollution Research, 2020
The aim of our study is to develop a one-step procedure to remove and degrade dyes from wastewate... more The aim of our study is to develop a one-step procedure to remove and degrade dyes from wastewater using a low-cost and efficient system based on aqueous two-phase system (ATPS), a well-known technique used to concentrate and recover enzymes. We investigated the catalytic proprieties of rice bran peroxidase (RBP) and found that this homemade enzyme can remain bound to its substrate for up to 5 days in controlled environments, without denaturing and while maintaining stable oxidation reduction potential (ORP) and pH. This biomolecule showed affinity for the ATPS technique prepared with polyethylene glycol and salt, which improved the relative activity up to 170%. The red dye separation in ATPS top phase was achieved in 3 min, in the RBP presence, with 100% of efficiency, and color removal of 87% was obtained in 24 h of enzymatic reaction. The process has promise to be scaled up to 10-fold and to reuse the reagents from the bottom phase of the ATPS.
The study gathered publications from 2003 to 2018 reporting the occurrence of aflatoxin M1 (AFM1)... more The study gathered publications from 2003 to 2018 reporting the occurrence of aflatoxin M1 (AFM1) in samples of milk and milk products from Latin America. Results showed that in 3547 milk and 969 d...
Peroxidases pertencem a familia das oxidorredutases cuja funcao e catalisar a oxidacao de substra... more Peroxidases pertencem a familia das oxidorredutases cuja funcao e catalisar a oxidacao de substratos orgânicos tendo H2O2 e outros peroxidos como moleculas aceptoras. Diversas aplicacoes sao atribuidas a essas enzimas, e sua purificacao depende da sua aplicacao final. O objetivo deste trabalho foi verificar a influencia de diferentes sais na etapa de eluicao durante purificacao peroxidases por cromatografia de troca ionica (CTI) em coluna de leito expandido. Para tal, foi avaliado o uso de sais como NaCl, CaCl2 e KCl na concentracao de 1 mol/L, bem como o uso combinado de NaCl 1 mol/L e CaCl2 0,001 mol/L. O uso da eluicao em modo degrau de 0,15 mol/L e gradiente linear de 0,15 a 1 mol/L de NaCl acrescido de 0,001 mol/L de CaCl2 em tampao acetato de sodio 0,025 mol/L pH 5,5, proporcionou fator de purificacao e recuperacao enzimatica de 14,6 vezes e 51,5%, respectivamente.
This study aimed to investigate the effects of magnetic field (MF) application (1, 12 and 24 h da... more This study aimed to investigate the effects of magnetic field (MF) application (1, 12 and 24 h day −1) to Spirulina sp. LEB 18 in different photosynthesis cycles (dark and/or light) during short (15 days) and long periods (50 days) of cultivation. MF application was performed via two sources: ferrite magnets and solenoids. At the end of cultivation, the biomass was characterized in terms of lipids, proteins, and carbohydrates. In the 15 day cultures, the highest maximum biomass concentrations (2.06 g L−1 and 1.83 g L−1) were observed when 30 mT was applied for 24 h day −1 or 12 h day −1 (on the light cycle), respectively. MF application throughout cultivation (24 h day −1) for more than 30 days is not recommended. In all conditions, there was an increase in the lipid concentration (from 14 to 45%). The protein profile suggested important changes in photosystems I and II due to MF application. Cell morphology was not altered by MF application. In conclusion, the effects on the metabolism of Spirulina sp. are directly related to the photosynthesis cycle and time period in which the MF was applied.
ABSTRACT In this study Aflatoxin B1 (AFB1), ochratoxin A (OTA) and zearalenone (ZEN) occurrence i... more ABSTRACT In this study Aflatoxin B1 (AFB1), ochratoxin A (OTA) and zearalenone (ZEN) occurrence in fish feed, regarding its chemical composition, were investigated. Besides, AFB1 bioaccessibility to fish was evaluated by in vitro digestion. Mycotoxins were extracted by QuEChERS and quantified by HPLC-FLD. Results showed that 93.3% of the samples were contaminated at maximum levels of 16.5, 31.6, and 322 µg/kg in the cases of AFB1, OTA, and ZEN, respectively. A positive correlation between OTA, ZEN contamination, and lipid content was observed. Risk estimation of feed consumption by fish at the highest levels of AFB1, OTA, and ZEN shows that the younger the fish, the higher the risk of exposure to mycotoxins. The AFB1 bioaccessibility assay showed that 85% of this mycotoxin may be absorbed by fish. Therefore, establishing maximum levels in the fishing sector is fundamental to contribute to feed quality and nutritional safety of fish species.
This study aimed at evaluating mitigation of nivalenol (NIV) in alcoholic fermentation with magne... more This study aimed at evaluating mitigation of nivalenol (NIV) in alcoholic fermentation with magnetic field application (MF). Mitigation was related to both the glutathione (GSH) redox molecule and the enzyme peroxidase (PO), which were synthesized by Saccharomyces cerevisiae US-05. Conditions under evaluation were NIV (0.2 µg mL-1), MF application (35 mT) and simultaneous use of mycotoxin and MF. The GSH content and the PO activity were increased when the culture contained NIV and the alcohol profile was altered after 48 h of fermentation. At the end of the alcoholic fermentation, NIV was mitigated by 56.5%. Therefore, this process is a promising method to reduce contamination by NIV, although the mycotoxin affects the chemical characteristics of the final product.
Abstract With the productive intensification of fish farming, the partial or total replacement of... more Abstract With the productive intensification of fish farming, the partial or total replacement of fishmeal by ingredients of plant origin became a reality within the feed industry, with the aim of reducing costs. However, this practice increased the impact of mycotoxin contamination. Studies have shown that mycotoxins can induce various disorders in fish, such as cellular and organic alterations, as well as impair functional and morphological development, and, in more severe cases, mortality. Thus, studies have been conducted to evaluate and develop strategies to prevent the formation of mycotoxins, as well as to induce their elimination, inactivation or reduction of their availability in feed.
Peroxidase is an enzyme in the group of oxidoreductases that is widely distributed in nature. It ... more Peroxidase is an enzyme in the group of oxidoreductases that is widely distributed in nature. It can catalyze the oxidation of various organic and inorganic substrates by reacting with hydrogen peroxide and similar molecules. Due to its wide catalytic activity, peroxidases can act in the removal of both phenolic compounds and peroxides, in chemical synthesis and, according to recent studies, in mycotoxin degradation. Therefore, this study aimed at introducing an overview of the mechanism of peroxidase action, extraction sources, mycotoxin degradation capacity and other potential applications in the food industry.
Environmental Science and Pollution Research, 2020
The aim of our study is to develop a one-step procedure to remove and degrade dyes from wastewate... more The aim of our study is to develop a one-step procedure to remove and degrade dyes from wastewater using a low-cost and efficient system based on aqueous two-phase system (ATPS), a well-known technique used to concentrate and recover enzymes. We investigated the catalytic proprieties of rice bran peroxidase (RBP) and found that this homemade enzyme can remain bound to its substrate for up to 5 days in controlled environments, without denaturing and while maintaining stable oxidation reduction potential (ORP) and pH. This biomolecule showed affinity for the ATPS technique prepared with polyethylene glycol and salt, which improved the relative activity up to 170%. The red dye separation in ATPS top phase was achieved in 3 min, in the RBP presence, with 100% of efficiency, and color removal of 87% was obtained in 24 h of enzymatic reaction. The process has promise to be scaled up to 10-fold and to reuse the reagents from the bottom phase of the ATPS.
The study gathered publications from 2003 to 2018 reporting the occurrence of aflatoxin M1 (AFM1)... more The study gathered publications from 2003 to 2018 reporting the occurrence of aflatoxin M1 (AFM1) in samples of milk and milk products from Latin America. Results showed that in 3547 milk and 969 d...
Peroxidases pertencem a familia das oxidorredutases cuja funcao e catalisar a oxidacao de substra... more Peroxidases pertencem a familia das oxidorredutases cuja funcao e catalisar a oxidacao de substratos orgânicos tendo H2O2 e outros peroxidos como moleculas aceptoras. Diversas aplicacoes sao atribuidas a essas enzimas, e sua purificacao depende da sua aplicacao final. O objetivo deste trabalho foi verificar a influencia de diferentes sais na etapa de eluicao durante purificacao peroxidases por cromatografia de troca ionica (CTI) em coluna de leito expandido. Para tal, foi avaliado o uso de sais como NaCl, CaCl2 e KCl na concentracao de 1 mol/L, bem como o uso combinado de NaCl 1 mol/L e CaCl2 0,001 mol/L. O uso da eluicao em modo degrau de 0,15 mol/L e gradiente linear de 0,15 a 1 mol/L de NaCl acrescido de 0,001 mol/L de CaCl2 em tampao acetato de sodio 0,025 mol/L pH 5,5, proporcionou fator de purificacao e recuperacao enzimatica de 14,6 vezes e 51,5%, respectivamente.
This study aimed to investigate the effects of magnetic field (MF) application (1, 12 and 24 h da... more This study aimed to investigate the effects of magnetic field (MF) application (1, 12 and 24 h day −1) to Spirulina sp. LEB 18 in different photosynthesis cycles (dark and/or light) during short (15 days) and long periods (50 days) of cultivation. MF application was performed via two sources: ferrite magnets and solenoids. At the end of cultivation, the biomass was characterized in terms of lipids, proteins, and carbohydrates. In the 15 day cultures, the highest maximum biomass concentrations (2.06 g L−1 and 1.83 g L−1) were observed when 30 mT was applied for 24 h day −1 or 12 h day −1 (on the light cycle), respectively. MF application throughout cultivation (24 h day −1) for more than 30 days is not recommended. In all conditions, there was an increase in the lipid concentration (from 14 to 45%). The protein profile suggested important changes in photosystems I and II due to MF application. Cell morphology was not altered by MF application. In conclusion, the effects on the metabolism of Spirulina sp. are directly related to the photosynthesis cycle and time period in which the MF was applied.
ABSTRACT In this study Aflatoxin B1 (AFB1), ochratoxin A (OTA) and zearalenone (ZEN) occurrence i... more ABSTRACT In this study Aflatoxin B1 (AFB1), ochratoxin A (OTA) and zearalenone (ZEN) occurrence in fish feed, regarding its chemical composition, were investigated. Besides, AFB1 bioaccessibility to fish was evaluated by in vitro digestion. Mycotoxins were extracted by QuEChERS and quantified by HPLC-FLD. Results showed that 93.3% of the samples were contaminated at maximum levels of 16.5, 31.6, and 322 µg/kg in the cases of AFB1, OTA, and ZEN, respectively. A positive correlation between OTA, ZEN contamination, and lipid content was observed. Risk estimation of feed consumption by fish at the highest levels of AFB1, OTA, and ZEN shows that the younger the fish, the higher the risk of exposure to mycotoxins. The AFB1 bioaccessibility assay showed that 85% of this mycotoxin may be absorbed by fish. Therefore, establishing maximum levels in the fishing sector is fundamental to contribute to feed quality and nutritional safety of fish species.
This study aimed at evaluating mitigation of nivalenol (NIV) in alcoholic fermentation with magne... more This study aimed at evaluating mitigation of nivalenol (NIV) in alcoholic fermentation with magnetic field application (MF). Mitigation was related to both the glutathione (GSH) redox molecule and the enzyme peroxidase (PO), which were synthesized by Saccharomyces cerevisiae US-05. Conditions under evaluation were NIV (0.2 µg mL-1), MF application (35 mT) and simultaneous use of mycotoxin and MF. The GSH content and the PO activity were increased when the culture contained NIV and the alcohol profile was altered after 48 h of fermentation. At the end of the alcoholic fermentation, NIV was mitigated by 56.5%. Therefore, this process is a promising method to reduce contamination by NIV, although the mycotoxin affects the chemical characteristics of the final product.
Abstract With the productive intensification of fish farming, the partial or total replacement of... more Abstract With the productive intensification of fish farming, the partial or total replacement of fishmeal by ingredients of plant origin became a reality within the feed industry, with the aim of reducing costs. However, this practice increased the impact of mycotoxin contamination. Studies have shown that mycotoxins can induce various disorders in fish, such as cellular and organic alterations, as well as impair functional and morphological development, and, in more severe cases, mortality. Thus, studies have been conducted to evaluate and develop strategies to prevent the formation of mycotoxins, as well as to induce their elimination, inactivation or reduction of their availability in feed.
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