Geciane Toniazzo Backes

Biotechnological potential of agro-industrial waste in the synthesis of pectin lyase from Aspergillus brasiliensis

This study aims at investigating pectin lyase bioproduction in submerged fermentation with synthetic medium and agro-industrial residues, using the filamentous fungus Aspergillus brasiliensis. The maximum pectin lyase activity in a synthetic medium (42 g/l pectin, 40 g/l yeast extract, and 0.02 g/l iron sulfate) was 31 U/ml, and 46 U/ml in the agro-industrial medium (160 g/l orange peel, 150 g/l corn steep liquor, and 300 g/l parboiled rice water), obtained over 60 and 124 h of bioproduction, 180 r/min, 30 ℃, pHinitial 5.5, and 5·106 spores/ml, respectively. Partial characterization of pectin lyase crude enzyme extract obtained from the synthetic medium and the one made of agro-industrial residues showed optimum conditions at pH of 5.5 and 4.5 and temperatures of 37 and 55 ℃, respectively. The Ed obtained was 3.13 and 9.15 kJ/mol, and the half-life time (t1/2) was 5.71 and 80 h at 55 ℃ for pectin lyase produced in synthetic and agro-industrial medium, respectively.

Production and characterization of Penicillium brasilianum pectinases with regard to industrial application

Abstract The objective of this study was to evaluate the production of pectinase by an isolated strain of Penicillium brasilianum in a bioreactor and to consider its potential for industrial applications (i.e. fruit juice). The optimization of production was achieved through experimental design. The maximum exo-polygalacturonase (Exo-PG) production in the bioreactor was 53.8 U mL−1 under the conditions of 180 rpm, an aeration rate of 1.5 vvm, 30 °C, pHinitial of 5.5, 5 × 106 spores mL−1, 32 g L−1 pectin, 10 g L−1 of yeast extract and 0.5 g L−1 magnesium sulfate and bioproduction for 36 h. The production of Exo-PG in the bioreactor was 1.3 times higher than that obtained in shake flasks, with aeration (1.5 vvm) and agitation (180 rpm) control. The crude enzyme complex, beyond the pectinolytic activity of Exo-PG (53.8 U mL−1), also contained activity pectin methylesterase (6.0 U mL−1) and pectin lyase (6.61 U mL−1). At a crude enzyme complex with a concentration of 0.5% (v/v), viscosity of peach juice was reduced by 11.66%, turbidity was reduced by 13.71% and clarification was increased by 26.92%. Based on the present results, we can conclude that the new strain of isolated P. brasilianum produced high amounts of pectinases in a bioreactor with mechanical agitation, and has the potential to be applied to in the clarification of juices.

Water absorption and dripping of chicken breast and carcasses during pre-cooling in an industrial system

Abstract This study aimed to evaluate the parameters that influence the water absorption and drip of chicken carcasses due to the processing and pre‐cooling of the meat in an industrial chiller. A total of 1,179 chickens were sampled during industrial processing to evaluate the influence of variables, validate the parameters, and conduct histological analysis. The best parameters for guaranteeing absorption levels and drip tests within acceptable limits on chicken carcasses were total residence time of 60 min (in the pre‐chiller, chiller 1, and chiller 2); air pressure of chillers at 0.5 bar; the abdominal opening of carcasses at a maximum of 2 cm. These parameters did not influence the protein content, moisture/protein ratio, pH, or lipid content. The validation of the parameters and the histological analysis performed after each cooling stage showed that the most significant structural changes occurred in the pre‐chiller, where the temperature of carcasses and water was higher, which contributes to greater absorption.

Synthesis of Pectin Methylesterase from Aspergillus niger in Submerged Fermentation Using as Citrus Pectin and Orange Peel as Inducers

Abstract This work is a comparative study of the bioproduction of pectin methylesterase (PME) with medium composed of agro-industrial residues and synthetic medium using the filamentous fungus Aspe...