Author
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YAMAMOTO, SHIGEKI |
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Voss, Kenneth |
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Submitted to: Journal of Food Additives & Contaminants
Publication Type: Proceedings Publication Acceptance Date: 8/15/2008 Publication Date: 9/12/2008 Citation: Yamamoto, S., Voss, K.A. 2008. Meeting the challenges of toxic microorganisms and pathogens: Implications for food safety and public health. Journal of Food Additives & Contaminants. 25(9):1047-1049. Interpretive Summary: An interdisciplinary approach is needed to meet the longstanding and emerging challenges for protecting animals and humans from illnesses caused by feed- or food-borne microorganisms and their toxins. The reports in this special issue illustrate some components of a broad-based approach for characterizing, managing and reducing health threats associated with food-borne pathogens and the mycotoxins produced by fungi found in commodities. Monitoring exposure intake is important to assess risk and the need for control measures. This is illustrated by Kumagai et al., who surveyed aflatoxin and ochratoxin A levels in selected retail foods from Japan. They found that exposure to these mycotoxins through consumption of most products, including cacao, is low but that further measures to control aflatoxin exposures are desirable. Physical and chemical treatments can be useful for reducing mycotoxin concentrations in harvested commodities and minimizing exposures in feed and food products. Murata et al. demonstrated the potential use of ultraviolet light for degrading the zearalenone and deoxynivalenol, mycotoxins which can be found together in grains and are toxic to swine. An example of a novel chemical method was described by Yabe et al., who have isolated the compound cyclo(L-leucyl-L-prolyl), from the bacteria, Achromobacter xylosoxidans, and showed that it inhibited aflatoxin production by Aspergillus parasiticus. Advances in fungal genomics have improved understanding of fundamental fungal biology and have contributed to the identification of potential control points for inhibiting mycotoxin biosynthesis by fungi. One approach for identifying the genes required for mycotoxin biosynthesis is to compare the genomes from closely related mycotoxin-producing and non-producing species, such as Aspergillus flavus and A. oryzae, as presented by Machida et al. Yu et al have also identified genes that are involved in aflatoxin production by using microarray analyses of A. flavus. The usefulness of genomics is further illustrated by Brown et al., who have used genome sequencing, Expressed Sequence Tags, and microarray analyses to reveal the genes of Fusarium verticillioides that are involved in synthesis of the mycotoxins, the fumonisins, which are toxic to farm animals and suspected risk factors for cancer or birth defects. Risk assessment and establishment of scientifically sound regulatory measures continue to be an important component of the strategy to minimize mycotoxin exposures. Characterizing the biological effects of mycotoxins, their underlying molecular mechanisms and determining dose-response are critical data for risk assessment. Pestka reviewed the molecular events involved in the immunologic and cytotoxic effects of deoxynivalenol, a trichothecene mycotoxin commonly found in wheat, barley and maize. Sugita-Konishi et al. reported the hematological, reproductive and other effects in mice of the related trichothecene, nivalenol. Other presentations covered recent advances in risk assessment, epidemiology and modeling of food poisoning outbreaks related to bacteria, trends in anti-microbial resistance, and evaluation of a high-throughput method for identification of bacteria involved in outbreaks. Technical Abstract: An interdisciplinary approach is needed to meet the longstanding and emerging challenges for protecting animals and humans from illnesses caused by feed- or food-borne microorganisms and their toxins. The reports in this special issue illustrate some components of a broad-based approach for characterizing, managing and reducing health threats associated with food-borne pathogens and the mycotoxins produced by fungi found in commodities. Monitoring exposure intake is important to assess risk and the need for control measures. This is illustrated by Kumagai et al., who surveyed aflatoxin and ochratoxin A levels in selected retail foods from Japan. They found that exposure to these mycotoxins through consumption of most products, including cacao, is low but that further measures to control aflatoxin exposures are desirable. Physical and chemical treatments can be useful for reducing mycotoxin concentrations in harvested commodities and minimizing exposures in feed and food products. Murata et al. demonstrated the potential use of ultraviolet light for degrading the zearalenone and deoxynivalenol, mycotoxins which can be found together in grains and are toxic to swine. An example of a novel chemical method was described by Yabe et al., who have isolated the compound cyclo(L-leucyl-L-prolyl), from the bacteria, Achromobacter xylosoxidans, and showed that it inhibited aflatoxin production by Aspergillus parasiticus. Advances in fungal genomics have improved understanding of fundamental fungal biology and have contributed to the identification of potential control points for inhibiting mycotoxin biosynthesis by fungi. One approach for identifying the genes required for mycotoxin biosynthesis is to compare the genomes from closely related mycotoxin-producing and non-producing species, such as Aspergillus flavus and A. oryzae, as presented by Machida et al. Yu et al have also identified genes that are involved in aflatoxin production by using microarray analyses of A. flavus. The usefulness of genomics is further illustrated by Brown et al., who have used genome sequencing, Expressed Sequence Tags, and microarray analyses to reveal the genes of Fusarium verticillioides that are involved in synthesis of the mycotoxins, the fumonisins, which are toxic to farm animals and suspected risk factors for cancer or birth defects. Risk assessment and establishment of scientifically sound regulatory measures continue to be an important component of the strategy to minimize mycotoxin exposures. Characterizing the biological effects of mycotoxins, their underlying molecular mechanisms and determining dose-response are critical data for risk assessment. Pestka reviewed the molecular events involved in the immunologic and cytotoxic effects of deoxynivalenol, a trichothecene mycotoxin commonly found in wheat, barley and maize. Sugita-Konishi et al. reported the hematological, reproductive and other effects in mice of the related trichothecene, nivalenol. Other presentations covered recent advances in risk assessment, epidemiology and modeling of food poisoning outbreaks related to bacteria, trends in anti-microbial resistance, and evaluation of a high-throughput method for identification of bacteria involved in outbreaks. |
