Cyclospora Cayetanensis-Major Outbreaks from Ready to Eat Fresh Fruits and Vegetables.

Cyclospora cayetanensis is a coccidian protozoan that causes cyclosporiasis, a severe gastroenteric disease, especially for immunocompromised patients, children, and the elderly. The parasite is considered as an emerging organism and a major contributor of gastroenteritis worldwide. Although the global prevalence of cyclosporiasis morbidity and mortality has not been assessed, global concern has arisen since diarrheal illness and gastroenteritis significantly affect both developing countries and industrialized nations. In the last two decades, an increasing number of foodborne outbreaks has been associated with the consumption of fresh produce that is difficult to clean thoroughly and is consumed without processing. Investigations of these outbreaks have revealed the necessity to increase the awareness in clinicians of this infection, since this protozoan is often ignored by surveillance systems, and to establish control measures to reduce contamination of fresh produce. In this review, the major cyclosporiasis outbreaks linked to the consumption of ready to eat fresh fruits and vegetables are presented.

Disruption and Overexpression of the Gene Encoding ACC (1-Aminocyclopropane-1-Carboxylic Acid) Deaminase in Soil-Borne Fungal Pathogen Verticillium dahliae Revealed the Role of ACC as a Potential Regulator of Virulence and Plant Defense.

It has been suggested that some microorganisms, including plant growth-promoting rhizobacteria, manipulate the level of ethylene in plants by degrading 1-aminocyclopropane-1-carboxylic acid (ACC), an ethylene precursor, into α-ketobutyrate and ammonia, using ACC deaminase (ACCd). Here, we investigated whether ACCd of Verticillium dahliae, a soil-borne fungal pathogen of many important crops, is involved in causing vascular wilt disease. Overexpression of the V. dahliae gene encoding this enzyme, labeled as ACCd, significantly increased virulence in both tomato and eggplant, while disruption of ACCd reduced virulence. Both types of mutant produced more ethylene than a wild-type (70V-WT) strain, although they significantly differed in ACC content. Overexpression strains lowered ACC levels in the roots of infected plants, while the amount of ACC in the roots of plants infected with deletion mutants increased. To test the hypothesis that ACC acts as a signal for controlling defense, roots of WT and Never-ripe (Nr) tomato plants were treated with ACC before V. dahliae inoculation. Plants pretreated with ACC displayed less severe symptoms than untreated controls. Collectively, our results suggest a novel role of ACC as a regulator of both plant defense and pathogen virulence.

Biodiversity and ochratoxin A profile of Aspergillus section Nigri populations isolated from wine grapes in Cyprus vineyards.

The objective of this study was to evaluate the biodiversity of Aspergillus section Nigri populations from Cyprus vineyards by morphological, toxigenic and phylogenetic analysis. Aspergillus section Nigri populations were isolated from grapes of the varieties 'Maratheftiko' and 'Cabernet Sauvignon' originating from six growing regions of Cyprus during 2010 and 2011 years. The isolation frequency of Aspergillus section Nigri from grape samples was 43.3% and a total of 284 isolates were selected for further analyses based on the macroscopic characteristics of black aspergilli. The isolates were characterized by sequencing analysis of the calmodulin gene in order to identify species responsible for ochratoxin A (OTA) production. The phylogenetic analysis showed that the isolates were grouped in three major clusters. The A. tubingensis cluster included 262 isolates (92.25%), the A. niger cluster included 15 isolates identified as A. niger (5.3%) and 6 isolates identified as A. welwitschiae (2.1%). One isolate was classified as A. carbonarius (0.35%) and was grouped in a cluster together with the reference isolates of A. carbonarius, A. sclerotioniger, A. sclerotiocarbonarius and A. ibericus. All the isolates were evaluated for their ochratoxigenic ability by HPLC coupled with a fluorescence detector (HPLC-FLD) and the positive isolates were re-examined using ultra high-performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS). The Aspergillus carbonarius isolate produced an average quantity of 1436.1 ng OTA/g Czapek Yeast Agar (CYA); From the A. niger strains three isolates (20%) produced OTA and only one isolate from A. welwitschiae (16.7%) was proved ochratoxigenic with toxin production average at 23.9 ng/g and 9.1 ng/g CYA respectively. Grape must samples derived from the collected berries were also analyzed for OTA and none of the samples were found contaminated with the mycotoxin. The results showed that the geographic area and the meteorological conditions had no significant effect on the incidence and the distribution of black aspergilli in this 2-year project. However, absence of rainfall and low humidity during the harvesting period were critical for the low incidence of the ochratoxigenic A. carbonarius on grapes.