Fumonisinas em produtos e em variedades de milho argentinos

AUTOR(ES)
DATA DE PUBLICAÇÃO

1998

RESUMO

Com, or maize (Zea mays L.), is the world third leading cereal crop, after wheat and rice. The United States produces nearly 40% of the total world production. The next largest comproducing countries are the People s Republic of China and Brazil. Argentinean com accounts for 2 percent of the total world production. In Argentina com occupies a third of the cultivated area and ranks third among cereals, after soybean and wheat. About 50% of Argentinean com is destined to export markets, mainly Asian countries and Brazil. Fumonisins are toxic metabolites of Fusarium moniliforme, which occurs widely in com. They cause mycotoxicosis in animais, such as equine leukoencephalomalacia and porcine pulmonary edema. Fumonisin B1 has been showed to be hepatocarcinogenic to rats. Fumonisins appear to be endemic in com and have been detected in a wide array of com-based products. In addition, the high incidence of human esophageal cancer in certain parts of the world, such as in Transkei, South Africa, and in Linxian, China, has been correlated with fumonisins presence in the food consumed locally. The first aim of the present work was to collect data on fumonisins incidence on com and com products produced by a neibouring country which is also an important Brazilian commercial partner. A second objective was to investigate possible factors responsible for fumonisins production in the field. The factors chosen were: cultivar, endosperm type, vegetative cycle length, temperature , relative humidity, and rainfall. With these objectives in mind (a) Fumonisin levels were investigated in com products offered to consumers in Buenos Aires, Argentina, and (b) Maize genotypes grown in Argentina during two consecutive growing seasons were examined for the incidence of fumonisins. Fumonisins B1 and B2 were determined in 35 samples of com flour and com grits destined to human consumption and purchased directly from Buenos Aires food shops and supermarkets during October 1996 to January 1997 and during the month of January 1998. During the first period of sample collecting, 16 out of 19 samples were found contaminated. Considering ali 19 samples contamination levels were between not detected and 1860 ng/g FB1, with an average of 300 ng/g, and from not detected to 768 ng/g FB2, with an average of 95 ng/g. During the second period ali 16 samples were found contaminanted with levels ranging from 75 to 4987 ng/g FB1, with an average of 844 ng/g, and from not detected to 1818 ng/g FB2, with an average of 304 ng/g. The levels of FB1 and FB2 in the samples collected during January 1998 were significatively higher than the samples collected during the period of October 1996 to January 1997. No signifficative difference was found in terms of fumonisins levels between the branded and the unbranded samples. The natural occurrence of fumonisin 81 (F81) and fumonisin 82 (F82) has been investigated in 37 full cycle hybrids and 29 intermediate cycle hibrids grown in Junin, and 42 full cycle hybrids and 32 intermediate cycle hybrids grown in Pergamino during the growing season of October 1995 to April 1996 and the growing season of October 1996 to Apri11997, respectively. The maize hybrids grown in Junin during the first season contained fumonisin 81 at levels ranging from not detected to 838 ng/g (mean concentration 131 ng/g) for intermediate cycle maize hybrids and from not detected to 662 ng/g for F82 (mean concentration 58 ng/g). Fumonisins 81 and 82 ranged from not detected to 470 ng/g for F81 (mean concentration of 62 ng/g) and from not detected to 138 ng/g for F82 (mean concentration of 13 ng/g) for full cycle maize hybrids. The maize hybrids grown in Pergamino during the second season contained fumonisins 81 and 82 at levels ranging from 66 to 11160 ng/g for F81 (mean concentration of 3183 ng/g) and from 27 to 3526 ng/g for F82 (mean concentration of 995 ng/g) for intermediate cycle maize hybrids. The levels of contamination ranged from 499 to 10791 ng/g for F81 (mean concentration of 3846 ng/g) and from 87 to 4597 ng/g for F82 (mean concentration of 1166 ng/g) for full cycle maize hybrids. Forty four of the com hybrids were planted during both growing seasons. No correlation was found between fumonisins levels and endosperm type, number of crosses of the hybrid, and vegetative cycle length. The fumonisins levels were significantly different from one growing season to the other as was the average monthly relative humidity but not the average monthly temperature and the total monthly rainfall.

ASSUNTO(S)

farinhas milho - argentina

ACESSO AO ARTIGO

Documentos Relacionados