Abstract
The aim of the study was to monitor the mycobiota in grape samples at 3 maturation stages (pea berry, early veraison and ripe berry) and to test the ability of selected Penicillium strains to produce mycotoxins in year 2014. Grapes came from Nitra wine growing region, Šintava subregion and were analyzed by plating methods. From Devín grape variety the 339 strains were detected and identified. The most abundant genera found by descending order were Alternaria (42.8%), Cladosporium (24.2%) and Epicoccum (10.0%). Penicillium expansum was isolated from all 3 maturation stages but in low average relative density (1.2%). From Frankovka modrá (Frankish) grape variety the 562 strains were detected and identified. The most abundant genera found by descending order were Alternaria (30.6%), Cladosporium (21.3%) and Penicillium (20.3%). Totally were identified 8 species of the genus Penicillium. The most important species, on the basis of the isolation from all maturation stages and relative density, was P. expansum. Selected isolates of Penicillium species were tested for their toxigenity, according to thin layer chromatography method. In total 14 Penicillium strains representing 3 potentially toxigenic species were tested for their toxigenic ability, namely P. expansum, P. griseofulvum and P. chrysogenum. Out of 14 strains, 64% produced et least one mycotoxin as revealed by the method used here.
Highlights
The grape microbial ecosystem is composed of highly diverse microorganisms, including yeasts, bacteria and fungi (Barata et al, 2012)
The changes occurred in the incidence of Alternaria, Cladosporium and Penicillium expansum, which decreased from early veraison to ripe berry
Two grape varieties Devín and Frankovka modrá (Blue Frankish) were collected in the maturation stages corresponding to pea berry, early veraison and harvest from the Nitra wine region
Summary
The grape microbial ecosystem is composed of highly diverse microorganisms, including yeasts, bacteria and fungi (Barata et al, 2012). Fungal spoilage of grapes causes substantial financial losses to growers and processors and may pose a health threat to the consumer if the contaminating fungi produce mycotoxins. Rotting and spoilage of grape berries before harvest can be caused by a variety of fungal species such as Alternaria spp., Aspergillus spp., Botrytis cinerea, Cladosporium spp., Eurotium spp., Penicillium spp. and Rhizopus spp. These genus are regarded as the main natural contaminants of grapes (Valero et al, 2005). It is important to identify fungal contaminants in grapes because some moulds can grow and produce mycotoxins while certain yeasts and moulds can cause infections or allergies (Tournas and Katsoudas, 2005). The major mycotoxigenic fungi that attack harvested fruits and vegetables are Aspergillus, Penicillium and Alternaria species – and the mycotoxins produced by them in the host tissues, e.g., aflatoxins, ochratoxin A, patulin and alternaria toxins (Barkai-Golan, 2001)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Journal of microbiology, biotechnology and food sciences
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
