Determination of Aspergillus section Flavi and their aflatoxin and cyclopiazonic acid production patterns in naturally dried figs


Heperkan D., Karbancioglu-Guler F.

Symposium Mycotoxin Prevention and Control in Agriculture, Louisiana, Amerika Birleşik Devletleri, 6 - 10 Nisan 2008, cilt.1031, ss.77-90 identifier identifier

  • Cilt numarası: 1031
  • Basıldığı Şehir: Louisiana
  • Basıldığı Ülke: Amerika Birleşik Devletleri
  • Sayfa Sayıları: ss.77-90

Özet

Aspergillus section Flavi contamination in naturally dried figs were investigated in samples collected from orchards. Isolated fungi were identified using morphological and phenotypic characteristics. Isolates in Aspergillus section Flavi from fig were tested for aflatoxin (AF) and cyclopiazonic acid (CPA) production using thin-layer chromatography (TLC)-high performance liquid chromatography (HPLC) and TLC respectively. Of fig samples collected from 115 different orchards before any treatment, forty three (37.4%) were contaminated with Aspergillus flaw's, whereas Aspergillus parasiticus contamination was rare - only in 4 samples (3.5%) of dried figs for two consecutive years. A. flavus is the predominant species among Aspergillus section Flavi members for figs (85.7%). In some sample groups, both nontoxic and aflatoxins B(1) and B(2) producing A. flavus strains were found together on the same fig sample; also both A. flavus (producing aflatoxins B(1) and B(2)) and A. parasiticus (producing aflatoxins B(1), B(2), G(1) and G(2)) were found together on the same fig sample. All aflatoxin producing A. flavus isolates also produced CPA. Most of the A. flavus strains produced aflatoxins B(1) and B(2) and CPA at the same time during the first and second year, with ratios of 71.9% and 62.5% respectively, averaging to 68.7%. A. flavus strains producing only AFB(1) and CPA were rare, with a ratio of 7.9% and 0% with an average of 6.2% for the first and second year, respectively. All A. parasiticus strains produced only aflatoxins B(1), B(2), G(1) and G(2) but no CPA. A. tamarii, another member of Aspergillus section Flavi, is rarely present in Turkish figs.