کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4369663 1616751 2007 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Nonaflatoxigenic Aspergillus flavus TX9-8 competitively prevents aflatoxin accumulation by A. flavus isolates of large and small sclerotial morphotypes
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک دانش تغذیه
پیش نمایش صفحه اول مقاله
Nonaflatoxigenic Aspergillus flavus TX9-8 competitively prevents aflatoxin accumulation by A. flavus isolates of large and small sclerotial morphotypes
چکیده انگلیسی

Aflatoxins are a family of highly toxic and carcinogenic toxins produced by several Aspergillus species. Aflatoxin contamination of agricultural commodities both pre- and postharvest is a serious food safety issue and a significant economic concern. Using nonaflatoxigenic A. flavus isolates to competitively exclude toxigenic A. flavus isolates in agricultural fields has become an adopted approach to reduce aflatoxin contamination. From screening subgroups of nonaflatoxigenic A. flavus, we identified an A. flavus isolate, TX9-8, which competed well with three A. flavus isolates producing low, intermediate, and high levels of aflatoxins, respectively. TX9-8 has a defective polyketide synthase gene (pksA), which is necessary for aflatoxin biosynthesis. Co-inoculating TX9-8 at the same time with large sclerotial (L strain) A. flavus isolates at a ratio of 1:1 or 1:10 (TX9-8:toxigenic) prevented aflatoxin accumulation. The intervention of TX9-8 on small sclerotial (S strain) A. flavus isolates varied and depended on isolate and ratio of co-inoculation. At a ratio of 1:1 TX9-8 prevented aflatoxin accumulation by A. flavus CA28 and reduced aflatoxin accumulation 10-fold by A. flavus CA43. No decrease in aflatoxin accumulation was apparent when TX9-8 was inoculated 24 h after toxigenic L- or S strain A. flavus isolates started growing. The competitive effect likely is due to TX9-8 outgrowing toxigenic A. flavus isolates.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Food Microbiology - Volume 114, Issue 3, 20 March 2007, Pages 275–279
نویسندگان
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