44G-20 |
Caffeine and poliphenolic compounds associated with mycotoxin production by toxigenic moulds from Ilex paraguariensis St. Hill |
I. L. NUNES1, D. D. Bortolato2, G. Hermanns3, H. H. C. Carvalho3, E. E. Badiale-Furlong1, and I. B. Noll3. (1) Chemistry Department - Food Science, Federal University of Rio Grande, Eng. Alfredo Huch, 475, Rio Grande, 96201-900, Brazil, (2) Chemistry Departament - Food Science, Federal University of Rio Grande, Eng. Alfredo Huch, 475, Rio Grande, 96201-900, Brazil, (3) Food Science and technology Institute, Federal University of Rio Grande do Sul, Box 15090, Porto Alegre, 91501-970, Brazil Ilex paraguariensis St. Hill called "erva-mate", is the symbol tree of Rio Grande do Sul, the southern state of Brazil. Mate or "chimarrão" is a traditional beverage from Argentina, Paraguay, Uruguay and South Brazil, prepared from the well dried powder, originated from the harvested leaves of erva-mate. Although high temperatures are reached in processing erva-mate, the presence of moulds have been reported in the literature, mainly from Argentine. Caffeine contents has been associated as a inhibitor of mycotoxins production. Taking these facts into consideration the objectives of this study was to evaluate the presence of moulds in erva-mate, observe their toxigenic potential, identify the mycotoxin production and its relation to the caffeine and poliphenolic levels detected. Samples of erva mate (1 Kg) were purchased at supermarkets of Porto Alegre city, the capital of the State Rio Grande do Sul. Caffeine content was analyzed by UV and the poliphenolic compounds extracted with methanol, cleaned with precipitant agents and quantified by spectrofotometric method. Potato Dextrose Agar was utilized for the mould counts, Sabouraud Dextrose Agar for the isolation of the strains and Coconut Agar for the mycotoxigenic potential analysis. Mycotoxins (aflatoxins, ochratoxins and zearalenone) were analyzed by a multitoxin thin layer chromatographic method. The average total counts for filamentous fungi obtained in PDA ranged from <10 to 1,1 x 102cfu-1. The genus Aspergillus spp. (64 %) was the most prevalent fungi with 5% mycotoxigenic potential. Aflatoxins, ochratoxins and zearalenone were´nt detected in the samples analyzed. The average levels of caffeine were 0,36 - 0,97% and poliphenolic compounds were detected in levels ranging 946 - 1465 ug/g. The results suggest that the poliphenolic and caffeine contents of erva mate represent an important role in the mycotoxin production, considering the high incidence of potential toxigenic moulds and the absence of toxins.
Session 44G, Toxicology & Safety Evaluation
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