Abstract
Some Alternaria species are able to produce plant pathogenic as well as toxic metabolites. In both agriculture and the food industry it is important know if toxigenic Alternaria are present to rapidly employ the correct corrective actions. The purpose of this work was to establish a real-time PCR method, which can detect and quantify apple pathogenic and toxigenic Alternaria. An AM-toxin I primer set, which could recognize Alternaria DNA only, was designed by using primers complementary to the AM-toxin I gene. The method could detect small amounts of DNA (4 pg) and still obtain a large dynamic range (4 decades) without interference from apple material. Eight Alternaria isolates were analyzed for the presence of AM-toxin I gene and their production of secondary metabolites. Then analyses showed that all eight isolates contained the AM toxin gene and were able to produce the plant pathogenic tentoxin in addition to AM toxin I. The analyses also showed the production of tenuazonic acid, alternariols, Altenuene, altenusin and/or altertoxin I in pure culture. Analyses of inoculated apples showed that both the AM-toxin gene and alternariol monomethyl ether could be detected. Morphological analyses suggested that the eight Alternaria strains, though they all carried the AM toxin genes, probably belong to different but closely related un-described Alternaria taxa in the A. tenuissima species-group based on morphological and chemical differences.
Original language | English |
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Journal | International Journal of Food Microbiology |
Volume | 111 |
Issue number | 2 |
Pages (from-to) | 105-111 |
Number of pages | 7 |
ISSN | 0168-1605 |
DOIs | |
Publication status | Published - 1 Sept 2006 |
Bibliographical note
Funding Information:The authors are grateful to Professor H. Otani for the donation of the AM-toxin standard and Professor E.G. Simmons for the Alternaria cultures. This work was partly supported by the Danish Ministry of Food, Agriculture and Fisheries through the program “Food Quality with a focus on Food Safety” and party by the LMC-Centre for Advanced Food Studies.
Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
Keywords
- Food fungi
- Metabolite profiles
- PCR
- Mycotoxins