Improving selenium extraction by sequential enzymatic processes for Se-speciation of selenium-enriched Agaricus bisporus.

M Dernovics; Zs Stefánka; P Fodor

doi:10.1007/s00216-001-1215-5

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Improving selenium extraction by sequential enzymatic processes for Se-speciation of selenium-enriched Agaricus bisporus.

M Dernovics·Zs Stefánka·P Fodor

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Abstract

Sample preparation methods based on the use of proteolytic and cell wall digesting enzymes for the speciation analysis of selenized mushroom were investigated. The sample (Agaricus bisporus; 160 microg total Se per g sample) was grown on compost supplemented with selenized yeast. Experiments were carried out to elucidate the possible role of the cell wall digesting enzymes--Lysing enzyme and Driselase--in the improvement of extraction efficiency with and without inhibiting proteolysis during cell wall digestion. A 3-step procedure applying Lysing enzyme and pronase gave the highest extraction efficiency (89%); however, the best species recovery was achieved by a one-step proteolytic procedure. All the procedures of selenium speciation were controlled by independent ICP-AES analysis measuring the total amount of selenium.

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Agaricus Cell Wall Endopeptidases Fungal Proteins Glycoside Hydrolases Selenium Compounds Spectrometry, Fluorescence Journal Article Research Support, Non-U.S. Gov't

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M Dernovics, Zs Stefánka, P Fodor. 2001-12-21. Improving selenium extraction by sequential enzymatic processes for Se-speciation of selenium-enriched Agaricus bisporus.. https://doi.org/10.1007/s00216-001-1215-5

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