| Full text | |
| Author(s): |
Massi, Fernanda Pelisson
;
Iamanaka, Beatriz Thie
;
Barbosa, Rafaella Liviero
;
Sartori, Daniele
;
Ferrranti, Larissa
;
Taniwaki, Marta Hiromi
;
Fungaro, Maria Helena Pelegrinelli
Total Authors: 7
|
| Document type: | Journal article |
| Source: | Brazilian Journal of Microbiology; v. 52, n. 1, p. 6-pg., 2020-10-22. |
| Abstract | |
The aim of this study was to isolate Aspergillus section Nigri from onion samples bought in supermarkets and to analyze the fungal isolates by means of molecular data in order to differentiate A. niger and A. welwitschiae species from the other non-toxigenic species of black aspergilli, and detect genes involved in the biosynthesis of ochratoxin A and fumonisin B-2. Aspergillus section Nigri were found in 98% (94/96) of the onion samples. Based on the results of multiplex PCR (performed on 500 randomly selected strains), 97.4% of the Aspergillus section Nigri strains were recognized as A. niger/A. welwitschiae. Around half of them were subjected to partial sequencing of the CaM gene to distinguish one from the other. A total of 97.9% of the isolates were identified as A. welwitschiae and only 2.1% as A. niger. The fum8 gene, involved in fumonisin B-2 biosynthesis, was found in 36% of A. welwitschiae isolates, but radH and pks genes, involved in ochratoxin A biosynthesis, were found in only 2.8%. The presence/absence of fum8 gene in the A. welwitschiae genome is closely associated with ability/inability of the isolates to produce fumonisin in vitro. Based on these results, we suggest that in-depth studies are conducted to investigate the presence of fumonisins in onion bulbs. (AU) | |
| FAPESP's process: | 13/05414-8 - Isolation, identification and development of molecular marks for evaluation of Aspergillus niger producers of fumonisin B2 and ochratoxin A |
| Grantee: | Beatriz Thie Iamanaka |
| Support Opportunities: | Regular Research Grants |