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Journal of the Brazilian Chemical Society

versão impressa ISSN 0103-5053

Resumo

CESTARI, Antonio R. et al. Factorial Design Evaluation of Some Experimental Factors for Phenols Oxidation using Crude Extracts from Jackfruit (Artocarpus integrifolia). J. Braz. Chem. Soc. [online]. 2002, vol.13, n.2, pp. 260-265. ISSN 0103-5053.  http://dx.doi.org/10.1590/S0103-50532002000200019.

This study presents some additional information on the alternative utilization of Jackfruit crude extracts in selective phenol oxidation reactions, using catechol and the o-, m- e p- cresols and pyrogallol substracts. The effects of pH, concentration of phosphate buffer and kinds of natural phenol extractors are evaluated. By using the conventional univariate procedure, the best enzymatic activities were obtained with the catechol substract, phosphate buffer (pH 5.0) at a concentration 0.10 mol L-1, and the commercial polymer Polyclar SB-100â as natural phenol extractor. Using a full 23 factorial design the best catalytic results were obtained by employing phosphate buffer at pH 5.0 and it 0.050 mol L-1. However, the kind of phenol extractor was not statistically important. The best results for selective catechol oxidation were obtained by using the multivariate technique. In this way, the multivariate methodology is indicated to increase the performance of the crude extract in the selective oxidation reactions.

Palavras-chave : homogeneous enzymatic catalysis; jackfruit; phenol oxidations; factorial designs.

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