A molecular method for detection of Aspergillus carbonarius in coffee beans.
Ochratoxin A (OTA) is a carcinogenic and nephrotoxic mycotoxin that has been detected in a variety of food products, including green coffee beans. About 80% of Aspergillus carbonarius strains collected from coffee beans are able to produce OTA on this substrate. The rapid identification of this fungal species would be desirable. RAPD assays were applied to identify amplification products specific for A. carbonarius. One selected fragment, denoted OPX7809, was cloned and sequenced. Based on the nucleotide sequence obtained, specific oligonucleotides (OPX7F809 and OPX7R809) were designed and used as primers for DNA amplification. One amplified band of 809 bp was obtained from A. carbonarius genomic DNA, whereas no amplified fragment from DNA of other Aspergillus species was detected. This PCR analysis was also successfully employed to detect A. carbonarius in coffee beans. This PCR assay could contribute to the early and rapid detection of the potential presence of OTA in coffee samples.
Centro de Ciências Biológicas, Universidade Estadual de Londrina, P.O. Box 6001, 86051-990 Londrina-PR, Brazil. fungaro@uel.br
Maria Helena Pelegrinelli
MH
Fungaro
Patrícia Cristina
PC
Vissotto
Danieli
D
Sartori
Laurival Antônio
LA
Vilas-Boas
Márcia Cristina
MC
Furlaneto
Marta Hiromi
MH
Taniwaki
D001230:Aspergillus / Q000235:genetics* / Q000302:isolation & purification*; D016000:Cluster Analysis; D040503:Coffea / Q000382:microbiology*; D016172:DNA Fingerprinting; D004271:DNA, Fungal / Q000737:chemistry / Q000302:isolation & purification; D009793:Ochratoxins / Q000032:analysis; D016133:Polymerase Chain Reaction; D019105:Random Amplified Polymorphic DNA Technique; D012639:Seeds / Q000382:microbiology*; D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA
D004271:DNA, Fungal; D009793:Ochratoxins