Aspergillus ibericus: a new species of section Nigri isolated from grapes.

As part of a study on the ochratoxin producing mycoflora of grapes, several Aspergillus strains were isolated and tested for their ochratoxin A (OTA) producing abilities. Aspergillus strains of the section Nigri, which did not produce detectable amounts of OTA but which had a similar morphology to A. carbonarius, were isolated from wine grapes and/or dried vine fruit in Portugal and Spain. These strains, however, have characters that allow morphological distinction from the other species in the section, particularly the conidia size (5-7 microm), which allows separation of the species from the two most common biseriate species in section Nigri: A. carbonarius (7-9 microm) and A. niger and its aggregate species (3-5 microm). The strains are described here as belonging to a new species, named A. ibericus. The validation of this new taxon is supported further by analysis of the ITS-5.8S rDNA and calmodulin gene sequences and by analysis of the amplified fragment length polymorphism (AFLP) patterns, which were consistent in separating these strains from other species in the section. A. ibericus strains do not produce OTA therefore they are interesting for biotechnological exploration because many metabolites with commercial value are produced by other species in the section.

[1]  B. Summerell,et al.  Gibberella konza (Fusarium konzum) sp. nov. from prairie grasses, a new species in the Gibberella fujikuroi species complex. , 2003, Mycologia.

[2]  Charles Thom,et al.  A Manual of the Penicillia , 1949 .

[3]  M. Nei,et al.  Mathematical model for studying genetic variation in terms of restriction endonucleases. , 1979, Proceedings of the National Academy of Sciences of the United States of America.

[4]  S. Mínguez,et al.  What is the source of ochratoxin A in wine? , 2002, International journal of food microbiology.

[5]  P. Battilani,et al.  Occurrence of ochratoxin A-producing fungi in grapes grown in Italy. , 2003, Journal of food protection.

[6]  K. O’Donnell,et al.  A multigene phylogeny of theGibberella fujikuroi species complex: Detection of additional phylogenetically distinct species , 2000 .

[7]  T. O. Larsen,et al.  Molecular characterization of ochratoxin A producing strains of the genus Penicillium. , 2002, Systematic and applied microbiology.

[8]  T. White.  Amplification and direct sequencing of fungal ribosomal RNA genes for phylogenetics , 1990 .

[9]  G. Mulè,et al.  PCR Assay for Identification of Aspergillus Carbonarius and Aspergillus Japonicus , 2004, European Journal of Plant Pathology.

[10]  José Cano,et al.  Taxonomy and significance of black aspergilli , 2004, Antonie van Leeuwenhoek.

[11]  P. Battilani,et al.  Ochratoxin a in Grapes and Wine , 2002, European Journal of Plant Pathology.

[12]  K. Raper,et al.  The genus Aspergillus , 1966 .

[13]  C. Magnoli,et al.  Mycoflora and ochratoxin‐producing strains of Aspergillus section Nigri in wine grapes in Argentina , 2003, Letters in applied microbiology.

[14]  A. Venâncio,et al.  Mycotoxin-producing and other fungi isolated from grapes for wine production, with particular emphasis on ochratoxin A. , 2005, Research in microbiology.

[15]  S. Mínguez,et al.  Ochratoxigenic species from Spanish wine grapes. , 2005, International journal of food microbiology.

[16]  Lucile Sage,et al.  Fungal microflora and ochratoxin a risk in French vineyards. , 2004, Journal of agricultural and food chemistry.

[17]  F J Cabañes,et al.  Ochratoxin A production by strains of Aspergillus niger var. niger , 1994, Applied and environmental microbiology.

[18]  C. Kubicek,et al.  Industrial acids and other small molecules. , 1992, Biotechnology.

[19]  F. Accensi,et al.  New PCR method to differentiate species in the Aspergillus niger aggregate. , 1999, FEMS microbiology letters.

[20]  J. Smedsgaard,et al.  Biochemical Characterization of Ochratoxin A-Producing Strains of the Genus Penicillium , 2001, Applied and Environmental Microbiology.

[21]  J. Pitt.  The genus Penicillium and its teleomorphic states Eupenicillium and Talaromyces , 1981 .

[22]  Armando Venâncio,et al.  Black Aspergillus species as ochratoxin A producers in Portuguese wine grapes. , 2003, International journal of food microbiology.

[23]  S. Marín,et al.  Occurrence of ochratoxin A and toxigenic potential of fungal isolates from Spanish grapes , 2004 .

[24]  J. Visser,et al.  Combined Molecular and Biochemical Approach Identifies Aspergillus japonicus and Aspergillus aculeatus as Two Species , 2001, Applied and Environmental Microbiology.

[25]  E. Creppy,et al.  Fungal flora and ochratoxin a production in grapes and musts from france. , 2002, Journal of agricultural and food chemistry.

[26]  J. Thompson,et al.  The CLUSTAL_X windows interface: flexible strategies for multiple sequence alignment aided by quality analysis tools. , 1997, Nucleic acids research.

[27]  J. Guarro,et al.  Molecular characterization, relatedness and antifungal susceptibility of the basidiomycetous hormographiella species and Coprinus cinereus from clinical and environmental sources , 1996, Antonie van Leeuwenhoek.

[28]  Jens Christian Frisvad,et al.  New ochratoxin A or sclerotium producing species in Aspergillus section Nigri. , 2004 .

[29]  F. Cabañes,et al.  Influence of pH and incubation time on ochratoxin A production by Aspergillus carbonarius in culture media. , 2005, Journal of food protection.

[30]  Sudhir Kumar,et al.  MEGA2: molecular evolutionary genetics analysis software , 2001, Bioinform..

[31]  S. E. Tjamos,et al.  Aspergillus niger and Aspergillus carbonarius in Corinth Raisin and Wine‐Producing Vineyards in Greece: Population Composition, Ochratoxin A Production and Chemical Control , 2004 .

[32]  N. Crosby,et al.  Confirmation of ochratoxin A by chemical derivatisation and high-performance liquid chromatography , 1980 .

[33]  F. Cabañes,et al.  DNA-based characterization of ochratoxin-A-producing and non-producing Aspergillus carbonarius strains from grapes. , 2005, Research in microbiology.

[34]  F. Cabañes,et al.  Effects of temperature and incubation time on production of ochratoxin A by black aspergilli. , 2004, Research in microbiology.

[35]  F J Cabañes,et al.  An easy screening method for fungi producing ochratoxin A in pure culture. , 2001, International journal of food microbiology.

[36]  Rita Serra.  Micoflora das uvas portuguesas e seu potencial para a contaminação das uvas com micotoxinas, com destaque para a ocratoxina A , 2005 .

[37]  C. Magnoli,et al.  Potential ochratoxin A producers from wine grapes in Argentina and Brazil , 2002, Food additives and contaminants.

[38]  F. Accensi,et al.  Aspergillus carbonarius as the main source of ochratoxin A contamination in dried vine fruits from the Spanish market. , 2003, Journal of food protection.

[39]  N. Saitou,et al.  The neighbor-joining method: a new method for reconstructing phylogenetic trees. , 1987, Molecular biology and evolution.

[40]  J. Pitt,et al.  Occurrence of fruit rot fungi (Aspergillus section Nigri) on some drying varieties of irrigated grapes , 2008 .