Multi-mycotoxins and mycoflora in commercial Brazilian roasted baru nuts (Dipteryx alata vog).

Baru nut is a tree nut obtained through sustainable extraction from the Brazilian Cerrado. It is an important economic source for rural communities and for environmental preservation of the region. The aim of this study was to evaluate the mycoflora and mycotoxins contamination in70 roasted baru nut samples available in the Brazilian market. For mycotoxin determination, an analytical method using a miniaturized Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method and ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was validated. Filamentous fungi were enumerated by spread-plate in Dichloran Rose Bengal Chloramphenicol agar and identification was performed by Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF/MS) and D2 ribosomal ribonucleic acid region sequencing. Among the analyzed baru nut samples, six (8.5%) showed contamination by alternariol with concentration levels ranging between 12.2 and 148.2 μg kg−1. Fumonisins B1 (242.7 μg kg−1) and B2 (27.6 μg kg−1) were found in one (1.4%) sample. No other mycotoxins, including regulated aflatoxins, were found. Eleven fungal strains were isolated and Penicillium spp. was the most frequently isolated genus. All fungal strains were identified to the genus level. None of the isolated fungal strains showed mycotoxigenic potential. Baru nuts comply with mycotoxin regulations, displaying lower contamination levels than other nuts. These findings support rural economic growth, sustainable harvesting practices, and the conservation of the Cerrado's native flora. • Fungal contamination was found in 14.3% of Brazilian roasted baru nuts. • Penicillium spp. was the most frequent fungal genus isolated. • Regulated aflatoxins were not found. • Alternariol was found in 8.5% of the samples. • Fumonisins (B1 and B2) were found in 1.4% of the samples. [ABSTRACT FROM AUTHOR]