Zearalenone is a mycotoxin produced by Fusarium species.It frequently contaminates cereals used for foods or animal feeds,especially deposited in crude corn oil.Certain amounts of zearalenone can be removed during ref...Zearalenone is a mycotoxin produced by Fusarium species.It frequently contaminates cereals used for foods or animal feeds,especially deposited in crude corn oil.Certain amounts of zearalenone can be removed during refining processes.In this study,we studied the influence of activated carbon and six industial absorbents(zeolite,diatomite,attapulgite,perlite,montmorillonite and activated clay)on the elimination of zearalenone during bleaching process of corn oil and explored the absorption mechanism of activated carbon.Results showed that activated carbon had an excellent adsorption capacity of zearalenone compared with the other six industrial adsorbents.For activated carbon,a high removal rate of zearalenone(exceeding 83%)from heavily zearalenone-polluted corn oil was achieved and the removal rate of zearalenone was kept above 60%after five regeneration cycles.The research on the adsorption mechanism of activated carbon showed that Freundlich adsorption isotherm model and pseudo-second-order kinetic model could well described the adsorption process.The thermodynamic study demonstrated that adsorption process was spontaneous and exothermic.Fourier transform infrared spectroscopy and Raman spectroscopy further revealed that activated carbon was effectively combined with zearalenone viaπ-πinteraction.Thus,activated carbon is an efficient and suitable adsorbent to control the levels of zearalenone during bleaching process of corn oil.This study not only proposed a systematic research scheme for the mechanism study of activated carbon for the elimination of zearalenone in corn oil,but also provided the scientific basis for developing effective methods to eliminate zearalenone in refined vegetable oils.展开更多
The widespread contamination by mycotoxins,especially zearalenone and aflatoxins,in crops and their by-products has caused severe undesirable effects on human health and commercial trade.Researchers had screened out m...The widespread contamination by mycotoxins,especially zearalenone and aflatoxins,in crops and their by-products has caused severe undesirable effects on human health and commercial trade.Researchers had screened out microorganisms from various media for degrading zearalenone and aflatoxins,and the results of a lot of studies showed that enzymes derived from microbial strains play a key role in degrading mycotoxins.Genetic engineering technology had been applied to improve the heterologously expressed degrading enzymes in several mature microbial hosts such as Escherichia coli and Pichia pastoris.The separated and purified recombinant enzyme had high activity in degrading mycotoxins in vitro.This review summarized the types of mycotoxins-degrading microorganisms and enzymes,and the progress on synthesis of heterologously expressed degrading enzymes by genetic engineering technology as well as related researches on improving the effect of degrading enzymes.We also prospected the future development in the study of using recombinant enzymes formed by genetic engineering technology to realize the simultaneous degradation of multiple mycotoxins in crops.展开更多
The natural curcumin-mediated photodynamic inactivation(PDI)was developed,and its inactivation potency against Fusarium graminearum in vitro and in vivo was systematically investigated by fluorescence probe assay,tryp...The natural curcumin-mediated photodynamic inactivation(PDI)was developed,and its inactivation potency against Fusarium graminearum in vitro and in vivo was systematically investigated by fluorescence probe assay,trypan blue staining,scanning electron microscope(SEM),confocal laser scanning microscopy(CLSM),etc.Results showed that under the irradiation of blue LED,the photosensitizer of curcumin was excited to generate massive reactive oxygen species(ROS)in the cells of F.graminearum,and the PDI completely inactivated their mycelia and spores under the treatment of 150μM curcumin and 10.8 J/cm^(2)irradiation.Further analysis found that the PDI ruptured the cellular microstructures,damaged the cell membrane by increasing its permeability and oxidizing the lipids,degraded the intracellular DNA and proteins inside the spores of F.graminearum.Meanwhile,the PDI also potently killed>99.99%spores of F.graminearum on maize under the treatment of 200μM curcumin and 10.8 J/cm^(2)irradiation.Moreover,the PDI suppressed the production of zearalenone(ZEN),and residual ZEN could not be detected after the storage of maize for 10 days.Therefore,this study systematically explored the inactivation efficiency of curcumin-mediated PDI against both the mycelia and spores of F.graminearum,which provides a valid and promising method to control the fungal hazards in grains.展开更多
基金This work was supported by the National Natural Science Foundation of China(No.31972110)the National Key Research and Development Program of China(2018YFD0401102).
文摘Zearalenone is a mycotoxin produced by Fusarium species.It frequently contaminates cereals used for foods or animal feeds,especially deposited in crude corn oil.Certain amounts of zearalenone can be removed during refining processes.In this study,we studied the influence of activated carbon and six industial absorbents(zeolite,diatomite,attapulgite,perlite,montmorillonite and activated clay)on the elimination of zearalenone during bleaching process of corn oil and explored the absorption mechanism of activated carbon.Results showed that activated carbon had an excellent adsorption capacity of zearalenone compared with the other six industrial adsorbents.For activated carbon,a high removal rate of zearalenone(exceeding 83%)from heavily zearalenone-polluted corn oil was achieved and the removal rate of zearalenone was kept above 60%after five regeneration cycles.The research on the adsorption mechanism of activated carbon showed that Freundlich adsorption isotherm model and pseudo-second-order kinetic model could well described the adsorption process.The thermodynamic study demonstrated that adsorption process was spontaneous and exothermic.Fourier transform infrared spectroscopy and Raman spectroscopy further revealed that activated carbon was effectively combined with zearalenone viaπ-πinteraction.Thus,activated carbon is an efficient and suitable adsorbent to control the levels of zearalenone during bleaching process of corn oil.This study not only proposed a systematic research scheme for the mechanism study of activated carbon for the elimination of zearalenone in corn oil,but also provided the scientific basis for developing effective methods to eliminate zearalenone in refined vegetable oils.
基金supported by Program for Innovative Research Team(in Science&Technology)in University of Henan Province(No.20IRTSTHN023)supported by Key research and development and promotion special project of Science and Technology Department of Henan Province,China(No.192102310254)。
文摘The widespread contamination by mycotoxins,especially zearalenone and aflatoxins,in crops and their by-products has caused severe undesirable effects on human health and commercial trade.Researchers had screened out microorganisms from various media for degrading zearalenone and aflatoxins,and the results of a lot of studies showed that enzymes derived from microbial strains play a key role in degrading mycotoxins.Genetic engineering technology had been applied to improve the heterologously expressed degrading enzymes in several mature microbial hosts such as Escherichia coli and Pichia pastoris.The separated and purified recombinant enzyme had high activity in degrading mycotoxins in vitro.This review summarized the types of mycotoxins-degrading microorganisms and enzymes,and the progress on synthesis of heterologously expressed degrading enzymes by genetic engineering technology as well as related researches on improving the effect of degrading enzymes.We also prospected the future development in the study of using recombinant enzymes formed by genetic engineering technology to realize the simultaneous degradation of multiple mycotoxins in crops.
基金supported by the National Key Research and Development Program of China(2022YFE0139500)National Natural Science Foundation of China(32102105)+3 种基金Guangdong Basic and Applied Basic Research Foundation(2024A15150130262023A1515140136)Special Projects in Key Areas of Higher Education Institution in Guangdong Province(2024ZDZX2090)Guangdong Provincial Key Laboratory of Intelligent Food Manufacturing(2022B1212010015)。
文摘The natural curcumin-mediated photodynamic inactivation(PDI)was developed,and its inactivation potency against Fusarium graminearum in vitro and in vivo was systematically investigated by fluorescence probe assay,trypan blue staining,scanning electron microscope(SEM),confocal laser scanning microscopy(CLSM),etc.Results showed that under the irradiation of blue LED,the photosensitizer of curcumin was excited to generate massive reactive oxygen species(ROS)in the cells of F.graminearum,and the PDI completely inactivated their mycelia and spores under the treatment of 150μM curcumin and 10.8 J/cm^(2)irradiation.Further analysis found that the PDI ruptured the cellular microstructures,damaged the cell membrane by increasing its permeability and oxidizing the lipids,degraded the intracellular DNA and proteins inside the spores of F.graminearum.Meanwhile,the PDI also potently killed>99.99%spores of F.graminearum on maize under the treatment of 200μM curcumin and 10.8 J/cm^(2)irradiation.Moreover,the PDI suppressed the production of zearalenone(ZEN),and residual ZEN could not be detected after the storage of maize for 10 days.Therefore,this study systematically explored the inactivation efficiency of curcumin-mediated PDI against both the mycelia and spores of F.graminearum,which provides a valid and promising method to control the fungal hazards in grains.
