0000000000976654
AUTHOR
Misericordia Jiménez Escamilla
Rapid characterization of potential ochratoxin-producing fungi isolated from grapes and study of natamycin efficacy for its control
Fungal flora on ripe grape and fungi characterization are very critical for assessing the risk of OTA presence in wine, a mycotoxin classified as possible carcinogen to humans. In the present work, the PCR-RFLP technique has been applied to the ITS1- 5.SS-ITS2 region of the rDNA to carry out the characterization of potential OTA producing species of Aspergillus section Nigri from different grape varieties grown in Spain. The toxin production levels of the different isolates have also been analysed and the ability of natamycin, a fungicide, to control fungal development and OTA production in vitro has been studied, as well as the interaction with environmental factors {water activity, temper…
Study of Spanish Grape Mycobiota and Ochratoxin A Production by the Isolates of Aspergillus tubingensis and other Aspergillus section Nigri
The native mycobiota of five grape varieties grown in Spain has been studied. Four (Bobal, Tempranillo, Garnacha, and Monastrell) were red varieties and one (Moscatel) was white. The main fungal genera isolated were Alternaria, Cladosporium, and Aspergillus. The isolation frequency of Aspergillus spp. section Nigri in contaminated samples was 82%. Ochratoxin A (OTA) production was assessed using yeast extract-sucrose broth supplemented with 5% bee pollen. Cultures of 205 isolates from this section showed that 74.2% of Aspergillus carbonarius and 14.3% of Aspergillus tubingensis isolates produced OTA at levels ranging from 1.2 to 3,530 ng/ml and from 46.4 to 111.5 ng/ml, respectively. No Asp…