Mycotoxin-producing and other fungi isolated from grapes for wine production, with particular emphasis on ochratoxin A

Abstract

Mycotoxins are toxic secondary metabolites produced by filamentous fungi that have been detected in food commodities, including grapes and wine. A survey was conducted to assess mycotoxin-producing fungi in grapes destined for wine production. The mycotoxigenic capacity of the isolates was tested in culture media. Grapes were analyzed by plating methods from 4 Portuguese wine-growing regions at 3 maturation stages (pea berry, early veraison and ripe berry) between 2001 and 2003. From the 10,602 strains detected and identified, the most frequent genera were Cladosporium (25%), Alternaria (24%), Botrytis (15%), Penicillium (9%) and Aspergillus (8%). Most (92.0%) were non-mycotoxigenic or produced mycotoxins of unknown relevance to health. Potential producers of ochratoxin A (OTA) (Aspergillus niger aggregate, 5.4%, Aspergillus carbonarius, 0.6%) and trichothecenes (Fusarium spp., 0.4%; Trichothecium roseum, 0.8%) were the most frequent mycotoxigenic species isolated from grapes. OTA was detected in all cultures of A. carbonarius and 4% of A. niger aggregate strains. There was potential for OTA and trichothecene production in grapes by A. carbonarius and T. roseum, respectively, prior to harvest time. Data presented herein indicate that A. carbonarius is most likely to occur in vineyards with Mediterranean climates, while T. roseum is more likely to occur in more temperate climates, and is associated with gray rot. The present work emphasizes the need to use grapes under good condition so as to reduce the risk of contamination with mycotoxigenic fungi and subsequent mycotoxin occurrence in wine.

Alternaria mycotoxins associated with grape berries in vitro and in situ

“…(Serra et al 2005;Bellí et al 2006) and confirmed that this species belong to the mycoflora of wine grapes. Significant changes occurred in the incidence of Alternaria spp.…”

Effects of different mycotoxins on humans, cell genome and their involvement in cancer

“…5) for their lethal effect on humans and animal. Aflatoxin B1 has the highest carcinogenicity among all mycotoxins and it is capable of penetrating the cell membrane and attach to its DNA where it makes changes to the genome in order to become more stable (2,82,83). Aflatoxin B1 is considered a liposoluble compound which can be absorbed from the site of exposure and move into the blood stream throughout the body (84).…”

Determination of mycotoxin profiles characteristic ofAlternariastrains isolated from Malbec grapes

“…was observed with the maturation of the berries [36,37,39,41]; however in Slovenia, A. alternata increased its incidence in 2008 and decreased in 2009; while the incidence of A. tenuissima was maintained in 2008 and declined in 2009 [13].…”

“…The incidence of Alternaria in grapes has been reported in different percentages with respect to total mycobiota: 5-23% in USA, 25% in Italy, 80% in Argentina; 3-18%, 24%, 17% in different studies in Portugal, 75%, 3-58%, 13% in Spain, and A. alternata and A. tenuissima were reported in 16-19% in Slovakia [7,8,13,15,24,25,[35][36][37][38][39][40][41][42].…”