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  • Author or Editor: E. Amorim x
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Abstract  

Twenty six bottom sediment samples were collected from the Cananéia estuary in summer and winter of 2005. Multielemental analysis was carried out by instrumental neutron activation analysis. Total mercury was determined by cold vapor atomic absorption. As, Cr, Hg and Zn concentrations were compared to the Canadian oriented values (TEL and PEL). Sample points 4 and 9 presented higher concentration for most elements and As and Cr exceeded the TEL values. Organic matter (>10%) associated with siltic and clay sediments was observed. Climatic conditions, hydrodynamic and biogeochemical processes promote differences in seasonal concentrations of elements at some points, which contribute to special distributions.

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Abstract  

The high costs of cereals and vegetable protein supplements used for animal nutrition have directed much attention toward non-conventional alternative protein sources. Brazil has a significant potential to provide such material, since it is the world’s largest producer of ethanol (13 billion liters per year) derived from fermentation by yeasts (sugar cane being the basic raw material). Distilleries are recovering surplus yeast to produce dry yeast for use in animal food formulations. With regard to the yeast biomass elemental composition, INAA analyses performed on a pool of samples from various different fermentations have shown the presence of various trace elements, e. g. As, Br, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Na, Rb, Sc, Sm, Th, and Zn. This reinforces the need for additional studies concerning the suitability of yeast in terms of maximum tolerable levels of these elements in formulations for domestic animals.

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