Molecular identification and aflatoxin screening of Aspergillus species found on Philippine dried fish products

Madelaine L. Ebarvia, Thomas Edison E. dela Cruz
Abstract:
Mycotoxin contamination due to toxigenic fungi occurs frequently in various food commodities. These can have serious human and animal health risks. In the Philippines, dried fish is widely distributed and are considered as an important commodity due to its availability in the market, ease of processing and cheapness. Testing of these market food products ensures food and consumers safety. This study therefore evaluated the occurrence of aflatoxin-producing Aspergillus from Philippine dried fish products found on its local markets. Thirty-one samples of eleven types of dried fish products from nine local markets were collected for the isolation of toxigenic fungi. A total of 115 Aspergillus isolates were recorded from all dried fish products. Morphological characterization grouped the isolates into nine morphospecies. Identification of these fungi using morphocultural characterization and sequence analysis of the ITS genes confirmed its identities as Aspergillus alliaceus, Aspergillus clavatus, Aspergillus flavus, Aspergillus niger, Aspergillus ochraceous, Aspergillus oryzae, Aspergillus steynii, Aspergillus tamarii var. 1, and Aspergillus tamarii var. 2. The nine morphosphecies were cultured and mass produced on Malt Extract Broth for 14 days for the detection of aflatoxin using TLC and HPLC. Aflatoxin was initially observed only in A. oryzae crude culture extracts with TLC, but absence was not confirmed by the HPLC analysis.
Keywords:
aflatoxin, Aspergillus, dried fish products, mycotoxin
Download:
IMEKO-TC23-2017-151.pdf
DOI:
-
Event details
IMEKO TC:
TC23
Event name:
3rd IMEKOFOODS Conference
Title:

Metrology Promoting Standardization and Harmonization in Food and Nutrition

Place:
Thessaloniki, GREECE
Time:
01 October 2017 - 04 October 2017