Publications by authors named "Sandra C Oliveira"

Free pectinase is commonly employed as a biocatalyst in wine clarification; however, its removal, recovery, and reuse are not feasible. To address these limitations, this study focuses on the immobilization of a commercial pectinolytic preparation (Pec) onto highly porous polymer microparticles (MPs). Seven microparticulate polyamide (PA) supports, namely PA4, PA6, PA12 (with and without magnetic properties), and the copolymeric PA612 MP, were synthesized through activated anionic ring-opening polymerization of various lactams.

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The use of free pectinases as clarification biocatalysts constitutes a well-established practice in the large-scale production of various types of wines. However, when in the form of free enzymes, the recovery and reusability of pectinases is difficult if not impossible. To address these limitations, the present study focuses on the noncovalent adsorption immobilization of a commercial pectinolytic preparation onto highly porous polyamide 6 (PA6) microparticles, both with and without magnetic properties, prepared via activated anionic polymerization.

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This study aimed to evaluate the effects of seed inoculation with Bradyrhizobium sp. and co-inoculation with Azospirillum brasilense. The seed treatments were as follows: control (without inoculation); A.

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Ultrahigh hydrostatic pressure (UHP) was applied to enhance the enzymatic hydrolysis of xylan in cellulosic fibers. The pretreatment improved xylan accessibility in the fiber cell wall and a 5-10-fold increase in the initial hydrolysis rate of xylan by xylanase was observed when Eucalyptus globulus kraft bleached pulp was pretreated at hydrostatic pressures of 300-400 MPa for 15-45 min. The rate and the extent of hydrolysis can be controlled by varying the pressure and the exposure time of UHP treatment prior to enzymatic hydrolysis.

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