Resumen

GODOY, Susmira; CHICCO, Claudio; MESCHY, François  y  REQUENA, Fanny. Phytic phosphorus and phytase activity of animal Feed Ingredients . INCI [online]. 2005, vol.30, n.1, pp.24-28. ISSN 0378-1844.

To determine total and phytic phosphorus and endogenous phytase activity in cereals, oilseeds and by-products, feed ingredients used in animal production in the tropics were evaluated. The cereals and by-products were yellow corn, sorghum, hard wheat, broken rice, wheat bran, fine and gross defatted corn germ and bran, and rice polishing; the oilseeds and by-products were cotton seed and cotton meal, and soy, palm oil and coconut meals. In five samples of each ingredient, phytic acid was measured by a colorimetric procedure and phytase activity with an enzymatic-colorimetric method. In addition, mineral and chemical components were determined by conventional methods. Crude protein, ether extract, ash and mineral content were similar to values reported in feed composition tables. Total P concentration in cereal grains and by-products ranged from 0.12 to 1.57%, and in oilseeds and by-products, from 0.43 to 1.34%. In cereals and oilseeds, phytic acid concentrations varied from 0.08 to 0.49%, and in by-products, from 0.24 to 1.13%. Significant regressions were found between total and phytic P in cereals and by-products, and in oilseeds and by-products. In the former, correlations were also found between phytic P and Mg, K and Ca content. Phytase activity (U/kg) was significantly higher in wheat (1565). Rice, wheat bran and rice polishing had values >100U/kg. The remaining grains and by-products did not show phytase activity.

Palabras clave : Cereals; Oilseeds; Phosphorus; Phytase; Phytate.