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Ochratoxin A (OTA) can occur in a wide range of foods, but unexpectedly high concentrations have been detected in dried vine fruits of various origins. The European Union has recently established a maximum OTA limit of 10 microg/kg for these foodstuffs. In order to determine the likely origin of OTA, a mycological study of 50 dried fruit samples (currants, raisins, and sultanas) representative of the Spanish market was conducted. Fungal contamination was detected in 49 of 50 (98%) samples. Black aspergilli were isolated from all of the positive samples. Aspergillus niger var. niger was isolated from 98% of the samples, and Aspergillus carbonarius was found in 58% of the samples. One hundred sixty-eight A. niger var. niger isolates and 91 A. carbonarius isolates were screened for their ability to produce OTA. Eighty-eight (96.7%) A. carbonarius isolates and one (0.6%) A. niger var. niger isolate were found to be OTA producers. Black aspergilli were the dominant fungi. Among black aspergilli, A. carbonarius has shown a consistent ability to produce OTA and is the most probable source of this mycotoxin in these substrates.

In a survey of the occurrence of ochratoxin A (OA)-positive strains isolated from feedstuffs, two of the 19 isolates ofAspergillus niger var. niger that were studied produced OA in 2% yeast extract-15% sucrose broth and in corn cultures. This is the first report of production of OA by this species.

Beauvericin is a cyclohexadepsipeptide mycotoxin which has insecticidal properties and which can induce apoptosis in mammalian cells. Beauvericin is produced by some entomo- and phytopathogenicFusarium species (Fusarium proliferatum,F. semitectum, and F. subglutinans) and occurs naturally on corn and corn-based foods and feeds infected byFusarium spp. We tested 94 Fusarium isolates belonging to 25 taxa, 21 in 6 of the 12 sections of theFusarium genus and 4 that have been described recently, for the ability to produce beauvericin. Beauvericin was produced by the following species (with the number of toxigenic strains compared with the number of tested strains given in parentheses): Fusarium acuminatum var. acuminatum (1 of 4), Fusarium acuminatum var. armeniacum (1 of 3), F. anthophilum (1 of 2), F. avenaceum (1 of 6), F. beomiforme (1 of 1), F. dlamini (2 of 2),F. equiseti (2 of 3), F. longipes (1 of 2),F. nygamai (2 of 2), F. oxysporum (4 of 7),F. poae (4 of 4), F. sambucinum (12 of 14), andF. subglutinans (3 of 3). These results indicate that beauvericin is produced by many species in the genusFusarium and that it may be a contaminant of cereals other than maize.

Ochratoxin A (OTA) producing fungi are members of the genera Aspergillus and Penicillium. Nowadays, there are about 20 species accepted as OTA producers, which are distributed in three phylogenetically related but distinct groups of aspergilli of the subgenus Circumdati and only in two species of the subgenus Penicillium. At the moment, P. verrucosum and P. nordicum are the only OTA producing species accepted in the genus Penicillium. However, during the last century, OTA producers in this genus were classified as P. viridicatum for many years. At present, only some OTA producing species are known to be a potential source of OTA contamination of cereals and certain common foods and beverages such as bread, beer, coffee, dried fruits, grape juice and wine among others. Penicillium verrucosum is the major producer of OTA in cereals such as wheat and barley in temperate and cold climates. Penicillium verrucosum and P. nordicum can be recovered from some dry-cured meat products and some cheeses.

Members of the genus Malassezia have rarely been associated with lagomorphs. During the course of an investigation of the lipophilic mycobiota of rabbit skin, two lipiddependent isolates which could not be identifi ed were recovered on Leeming and Notman agar medium from different animals. No growth of Malassezia yeasts was obtained either on Sabouraud ' s glucose agar or modifi ed Dixon agar media. In this study, we describe a new taxon, Malassezia cuniculi sp. nov., including its morphological and physiological characteristics. The validation of this new species was supported by analysis of the D1/ D2 regions of the 26S rRNA gene and the ITS-5.8S rRNA gene sequences. The results of these studies confi rm the separation of this new species from the other species of the genus Malassezia , as well as the presence of Malassezia yeasts on lagomorphs. (Table 1) and of these M. caprae , M. equina and M. nana have only been isolated from domestic animals [5].In this paper, we describe a new lipid-dependent species in the genus Malassezia isolated in the course of an investigation of the lipophilic mycobiota of the healthy skin of rabbits. For these isolates we proposed the name Malassezia cuniculi sp. nov. Material and methods Animals, sampling and culture media usedThe study was conducted during 2009 on 11 healthy New Zealand white male rabbits ( Oryctolagus cuniculus ) at the Rabbit Production Unit of the IRTA-Torre Marimon (Caldes de Monbui, Barcelona, Spain) which were used for breeding and meat production.Samples were collected from the external ear canals and the perianal, the inguinal and the submandibular areas of the skin. Perianal skin areas and right and left external ear canals of each animal were sampled by using a swab soaked in the wash fl uid, i.e., 0.075 mol/l phosphate-buffered physiological saline, pH 7.9 containing 0.1% Tween 80. Areas of the chin and groin were sampled using a modifi cation of the detergent scrub technique [6,7]. Skin areas were gently rubbed for 20 seconds with sterile tubes containing 2 ml of wash fl uid. Aliquots of 25 μ l of centrifuged wash fl uid (4000 rpm, 10 min) were inoculated onto paired quadrants of duplicate agar plates. Med Mycol Downloaded from informahealthcare.com by University of Nebraska on 01/05/15 For personal use only. © 2011 ISHAM, Medical Mycology, 49, 40-48 Malassezia cuniculi sp. nov.

Malassezia pachydermatis fungemia has been reported in patients receiving parenteral nutrition. Biofilm formation on catheters may be related to the pathogenesis of this mycosis. We investigated the biofilm-forming ability of 12 M. pachydermatis strains using a metabolic activity plate-based model and electronic microscopic evaluation of catheter surfaces. All M. pachydermatis strains developed biofilms but biofilm formation showed variability among the different strains unrelated to their clinical origin. This study demonstrates the ability of M. pachydermatis to adhere to and form biofilms on the surfaces of different materials, such as polystyrene and polyurethane.

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