Biodiversity of mycobiota throughout the Brazil nut supply chain: From rainforest to consumer. (February 2017)

• Record Type: Journal Article
• Authors: Taniwaki, Marta H.; Frisvad, Jens C.; Ferranti, Larissa S.; de Souza Lopes, Aline; Larsen, Thomas O.; Fungaro, Maria Helena P.; Iamanaka, Beatriz T.
• Is Part Of: Food microbiology. Volume 61(2017:Feb.)
• Page Start: 14
• Page End: 22
• Publication Date: 2017-02
• Subjects: Food Microbiology -- Periodicals; Aliments -- Microbiologie -- Périodiques; Food -- Microbiology; Periodicals; Food -- Microbiology -- Periodicals; Food contamination -- Periodicals; 664.001579
• DOI: 10.1016/j.fm.2016.08.002
• Languages: English
• ISSNs: 0740-0020

Abstract

Abstract: A total of 172 Brazil nut samples (114 in shell and 58 shelled) from the Amazon rainforest region and São Paulo state, Brazil was collected at different stages of the Brazil nut production chain: rainforest, street markets, processing plants and supermarkets. The mycobiota of the Brazil nut samples were evaluated and also compared in relation to water activity. A huge diversity of Aspergillus and Penicillium species were found, besides Eurotium spp., Zygomycetes and dematiaceous fungi. A polyphasic approach using morphological and physiological characteristics, as well as molecular and extrolite profiles, were studied to distinguish species among the more important toxigenic ones in Aspergillus section Flavi and A. section Nigri. Several metabolites and toxins were found in these two sections. Ochratoxin A (OTA) was found in 3% of A. niger and 100% of A. carbonarius. Production of aflatoxins B and G were found in all isolates of A. arachidicola, A. bombycis, A. nomius, A. pseudocaelatus and A. pseudonomius, while aflatoxin B was found in 38% of A. flavus and all isolates of A. pseudotamarii. Cyclopiazonic acid (CPA) was found in A. bertholletius (94%), A. tamarii (100%), A. caelatus (54%) and A. flavus (41%). Tenuazonic acid, a toxin commonly found in Alternaria species was produced by A. bertholletius (47%), A. caelatus (77%), A. nomius (55%), A. pseudonomius (75%), A. arachidicola (50%) and A. bombycis (100%). This work shows the changes of Brazil nut mycobiota and the potential of mycotoxin production from rainforest to consumer, considering the different environments which exist until the nuts are consumed. Highlights: Changes of Brazil nut mycobiota supply chain are described. Production of tenuazonic acid was found in several species of Aspergillus section Flavi . Over 50 species of fungi identified using polyphasic approaches.