Untitled

Abstract

A wide range of field and storage fungi were isolated from black pepper, white pepper and Brazil nut kernels from Amazonia. A total of 42 species were isolated from both peppers. Aspergillus flavus and A. niger were isolated more frequently from black than from white pepper. Other potential mycotoxigenic species isolated included: A. ochraceus, A. tamarii, A. versicolor, Emericella nidulans and Chaetomium globosum, Penicillium brevicompactum, P. citrinum, P. islandicum and P. glabrum. Species isolated from pepper for the first time were Acrogenospora sphaerocephala, Cylindrocarpon lichenicola, Lacellinopsis sacchari, Microascus cinereus, Petriella setifera and Sporormiella minima. Seventeen species were isolated from Brazil nut kernels. A. flavus was the dominant species followed by A. niger. P. citrinum and P. glabrum were the only penicillia isolated. Species isolated for the first time included Acremonium curvulum, Cunninghamella elegans, Exophiala sp., Fusarium oxysporum, Pseudoallescheria boydii, Rhizopus oryzae, Scopulariopsis sp., Thielavia terricola and Trichoderma citrinoviride. Considerably more metabolites were detected from black than white pepper in qualitative analyses. Chaetocin, penitrem A, and xanthocillin were identified only from black pepper, and tenuazonic acid was identified from both black and white pepper. Aflatoxin G2, chaetoglobosin C, and spinulosin were identified from poor quality brazil nuts. Aflatoxin B1 and B2 were also only detected in poor quality brazil nuts at concentrations of 27.1 micrograms kg-1 and 2.1 micrograms kg-1 respectively (total 29.2 micrograms kg-1).

Determinação de aflatoxina B1 em pimenta (Piper nigrum L.) e orégano (Origanum vulgare L.) por cromatografia em camada delgada e densitometria

“…No Brasil, Gatti et al 9 realizaram um monitoramento em duas das principais regiões produtoras de pimenta (Pará e Espírito Santo) e não detectaram aflatoxinas em 115 amostras de sementes secas de pimenta preta, utilizando a cromatografia em camada delgada como metodologia analítica. Resultados semelhantes foram encontrados por Freire et al 13 após analisarem 10 amostras de pimenta branca e preta da região da Amazônia. Semelhantemente, Elshafie et al 12 em Omã não detectaram aflatoxinas em 105 amostras de condimentos, inclusive pimenta preta.…”

“…Apesar de inúmeros trabalhos descritos na literatura relacionarem a ocorrência de aflatoxinas em diferentes tipos de alimentos, poucos descrevem sua presença em condimentos. 2,3,5,[9][10][11][12][13][14] Tradicionalmente, métodos analíticos para a determinação de aflatoxinas empregam extração das toxinas com solventes orgâni-cos, coluna de imunoafinidade, partição líquido-líquido ou coluna de fase sólida para a remoção de compostos interferentes e quantificação por cromatografia em camada delgada (CCD) ou cromatografia líquida de alta eficiência (CLAE). 4,[15][16][17][18][19] O monitoramento de aflatoxinas requer método simples, rápi-do, exato, preciso e sensível.…”

Characterization of Aspergillus species on Brazil nut from the Brazilian Amazonian region and development of a PCR assay for identification at the genus level

“…A total of three localities were sampled per state. Isolation into pure culture from shell tissues was performed according to Freire et al [45]. Single spore cultures were used throughout the study, with all strains preserved both in 20% glycerol at – 80°C and on silica gel at 4°C.…”

“…In order to test primer specificity in silico , electronic PCR was conducted using the program primersearch, available through The European Molecular Biology Open Software Suite (EMBOSS). Based upon BLAST searches, the specific primers were tested against both the NCBI nucleotide database and a local database of mtDNA SSU rDNA gene sequences for fungi documented on Brazil nut [29,45], comprising members of the genera Aspergillus , Acremonium, Chaetomium, Cladosporium, Colletotrichum, Exophiala, Fusarium, Graphium, Hypocrea, Paecilomyces, Penicillium, Phialophora, Phoma, Rhizopus and Trichoderma (Additional file 3). …”

Chaetocin induces apoptosis in human melanoma cells through the generation of reactive oxygen species and the intrinsic mitochondrial pathway, and exerts its anti-tumor activity in vivo

“…Chaetocin is a small-molecule natural product produced by Chaetomium species fungi [6,7], and its chemical structure belongs to diketoepiperazines, and was described in 1970 [8]. However, its effects on cellular processes were studied only in the two past decades.…”