196,106 research outputs found
Food Coloring Agents and Plant Food Supplements Derived from Vitis vinifera: A New Source of Human Exposure to Ochratoxin A
No full textGrape pomaces are increasingly being used as starting material in the industrial production of plant food supplements (PFS), food coloring, and tartrates, but they are at risk of ochratoxin A (OTA) contamination, a mycotoxin with nephrotoxic and carcinogenic effects. We analyzed 24 commercial PFS and 13 food coloring samples derived from Vitis vinifera, mainly pomaces, using a HPLC−FLD method for OTA determination. OTA was found in 75% of PFS samples and 69% of food coloring samples at levels of <1.16−20.23 μg/kg and <1.16−32.00 μg/kg, respectively. The four commercial leavening agents containing tartrates were found to be negative for OTA. All eight samples collected in two distilleries that use grape pomaces and wine lees to produce tartrates and other byproducts contained OTA at levels of <1.16−240.93 μg/kg. The high incidence of OTA contamination in PFS and food coloring agents derived from V. vinifera suggests that maximum permitted level(s) should be established for this mycotoxin in these products
Isolation and structure elucidation of isoaltenuene, a new metabolite of Alternaria alternata.
No full textIsolamento e caratterizzazione di metaboliti di Phomopsis helianthi con attività fitotossica
No full textStudi precedenti ed in particolare prove di patogenicità e analisi sull'estratto colturale dell'isolato F1 di Phomopsis helianthi avevano evidenziato la presenza di due composti, molto simili, solubili in solventi polari (acqua, metanolo, etanolo), insolubili in solventi apolari (cloruro di metilene, cloroformio, acetone), stabili a temperatura ambiente e a pH acido, fotosensibili. Le analisi spettroscopiche hanno confermato che trattasi due diastereoisomeri polichetidici derivati idrossilati della melleina.
Questa è la prima segnalazione sulla capacità di P.helianthi di produrre derivati della melleina
Isolamento di fitotossine da colture di Phomopsis helianthi
No full textQuattro isolati di Phomopsis helianthi, reperiti da piante infette in Francia (F1 e F2) e in Italia (I1 e I2) e dotati di un diverso grado di patogenicità sono stati messi in coltura su substrati artificiali per valutarne la capacità di produzione di fomozina (il cui standard non è reperibile in commercio) e/o di metaboliti secondari a questa correlati. L'isolato francese F1 di P.helianthi è risultato più fitotossico rispetto agli altri e capace di provocare necrosi e clorosi su foglie e su piantine di girasole. Dall'estratto colturale dell'isolato, allevato su riso, sono stati recuperati due composti che, analizzati tramite HPLC e spettro di massa sono risultati molto simili tra loro, probabilmente due isomeri, diversi comunque dalla fomozina
Patulin risk associated with blue mould of pome fruit marketed in southern Italy
No full textBlue mould is one of the most important postharvest diseases of pome fruit in all producing countries. It is mainly associated to Penicillium expansum that produces the mycotoxin patulin, although other species might be involved. The aim of the present study was to characterise Penicillium isolates associated with blue mould decay of pome fruit marketed in Apulia region (southern Italy), and verify their ability to produce patulin in vitro. Twenty-nine isolates of Penicillium spp. were recovered from pome fruit showing visible blue mould symptoms, and analysed for patulin production. After fungal isolation, the fruits were singularly analysed for patulin content. In general, the isolates proved to produce patulin and most of the pome fruit contained significant amounts of patulin, but there was no quantitative correspondence between in vitro and in vivo toxin accumulation. Isolate identification at species level was based on DNA analysis by P. expansum species-specific primers and sequencing of ß-tubulin gene. Furthermore, fungal isolates were tested for the occurrence of the patN gene coding the enzyme isoepoxydon dehydrogenase (IDH), involved in patulin metabolic pathway and considered a useful indicator of critical control points for patulin contamination. All 26 isolates identified as P. expansum were positive for patN and produced patulin. Moreover, three pear isolates belonging to other Penicillium species were found. They were positive for patN, but only two actually produced patulin. It can be concluded that toxigenic P. expansum isolates are associated with blue mould of pome fruit marketed in Apulia, thus a rapid detection is important to avoid patulin contamination beyond regulatory limits. Nevertheless, the presence of patN gene alone cannot be considered a predictive assay for patulin production. An evaluation of its expression level should be carried out
Toxicity of some Fusarium section Sporotrichiella strains in relation to mycotoxin production
No full textIdentification of bioactive metabolites produced by Trichoderma strains antagonistics towards phytopathogenic fungi
No full textTesting a toolbox for impact assessment of food safety regulations: maximum levels for T-2 and HT-2 toxins in the European Union
No full textIntroduction The aim of socio-economic research in the MoniQA Network of Excellence is to develop a toolbox to support impact assessment of proposed food safety regulatory changes. Objectives The scope of this contribution is to present an initial version of such a toolbox with its application to a case study, which concerns a proposal on setting maximum levels of T-2 and HT-2 toxins in cereals and cereal products. A regulatory proposal of ‘strict’ maximum limits is compared with two alternative options: the ‘do nothing’ option and the ‘soft’ regulatory option. Methods The proposed toolbox involves a preliminary qualitative assessment of the likely impacts of each of the policy options considered, with a coding/scoring procedure, in order to identify the greatest impacts. A feasibility filter subsequently considers the availability of data necessary for impact quantification. The subsequent quantitative assessment is performed with different methodologies for the most important impacts. Finally, a multi-criteria analysis approach – which allows for a combination of qualitative and quantitative measurements – is used to arrive at a ranking of policy options. Results The outcome of this assessment exercise is that the ‘do nothing’ option is clearly the most preferable option, and, between the two regulatory options (options 2 and 3), the setting out of ‘strict’ maximum limits is preferable to ‘soft’ maximum limits. Conclusion This case study shows the potentialities of the toolbox as support to policy makers, which will be improved and tested with additional case studies in the remaining years of the MoniQA Network of Excellence
Control of Penicillium expansum by an Epiphytic Basidiomycetous Yeast
No full textPostharvest biocontrol agents are considered a viable alternative to the use of synthetic chemicals as demonstrated by extensive research conducted by scientists and companies worldwide. In the present investigation, the biocontrol potential of a carotenoid-producing basidiomycetous yeast isolated from table grape flowers was analyzed. The strain RY1 proved to be Sporobolomyces roseus. In vitro and in vivo tests were conducted to assess its efficacy against Penicillium expansum, one of the most important postharvest pathogens and producer of the mycotoxin patulin. The yeast proved to control both fungal growth and patulin production, and, in addition, to greatly affect disease incidence and severity on apples. Its mode of action is presumably related both to the competition for nutrients and the production of antifungal volatiles. As such, although further large-scale trials are needed, our S. roseus strain represents a potential interesting biocontrol agent to be applied after harvest
Applicazione combinata di lieviti antagonisti e sostanze naturali contro la muffa verde-azzurra delle pomacee
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