Jamile Zeni

Experimental Design Applied to the Optimization and Partial Characterization of Pectin Liase from a Newly Isolated Penicillium brasilianum

Penicillium brasilianum was previously isolated from tea and identified by molecular biology technique. A Plackett-Burman design, followed by a complete second order design was used for the screening of most important factors and to maximize the pectin liase (PMGL) activity, respectively. The maximum PMGL activity by P. brasilianum achieved was 9.0 U/mL after 48 h of cultivation in a medium containing pectin (33.0 g/L), yeast extract (30.0 g/L) and potassium phosphate (2.0 g/L) at 30oC, with a stirring rate of 180 rpm, initial pH 5.5 and 5x106spores/mL inoculum size. The kinetic evaluation in terms of substrate consumption demonstrated that the maximum production of PMGL was at 72 h, and 40% of the total organic carbon, 25% of the nitrogen, 88% of the magnesium, 13% of the potassium and 66% of the iron were consumed. The pH remained almost stable during the whole period of production (5.33 to 4.9). The partial characterization of the crude PMGL enzyme extract showed optimal pH and temperature of 5.5 and 37°C, respectively.

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.

Inactivation of Staphylococcus aureus in raw salmon with supercritical CO2 using experimental design

Considering the microbial safety of consumption of raw foods (Asian food), this study aimed to explore the inactivation S. aureus in raw salmon by supercritical CO2 treatment (SC-CO2). For this purpose, experimental design methodology was employed as a tool to evaluate the effects of pressure (120-220 bar), the depressurization rate (10 to 100 bar.min–1) and the salmon:CO2 mass relation (1:0.2 to 1:1.0). It was observed that the pressure and the depressurization rate was statistically significant, i.e. the higher the system pressure and depressurization rate, the greater the microbial inactivation. The salmon: CO2 mass relation did not influence the S. aureus inactivation in raw salmon. There was a total reduction in S. aureus with 225 bar, a depressurizing rate of 100 bar.min–1, a salmon: CO2 mass relation of 1:0.6, for 2 hours at 33 °C.

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.

OPTIMIZATION OF SOLVENT-FREE GERANYL BUTANOATE PRODUCTION USING NOVOZYME 435 AND HOMEMADE POLYURETHANE IMMOBILIZED NOVOZYME NZL-102-LYO-HQ AS CATALYSTS

Carla R. Sbardelottoa, Suelen P. Piazzaa, Nadia L. D. Nyaria, Rogério M. Dallagoa, Débora de Oliveirab, Vladimir de Oliveirab, Jamile Zenia, Rogério L. Cansiana,* and Natalia Paroula Departamento de Engenharia de Alimentos, Universidade Regional Integrada do Alto Uruguai e das Missões, 99700-000 Erechim – RS, Brasil Departamento de Química e Engenharia de Alimentos, Universidade Federal de Santa Catarina, 88040-900, Florianópolis – SC, Brasil

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...

Experimental design applied to the optimization and partial characterization of pectin-methyl-esterase from a newly isolated Penicillium brasilianum

The objective of this work was to optimize the medium composition for maximum pectin-methylesterase (PME) production from a newly isolated strain of Penicillium brasilianum by submerged fermentation. A Plackett-Burman design was first used for the screening of most important factors, followed by a 2 3 full experimental design, to maximize the enzyme production. The maximum pectinmethyl-esterase activity was 4.0 U/mL at 24 h of bioproduction using a pectin concentration of 32.0 g/L, yeast extract of 30.0 g/L, potassium phosphate of 8.0 g/L, iron (II) sulfate of 0.02 g/L, at 30°C, stirring rate of 180 rpm and initial pH of 5.5. The kinetic evaluation showed that after 27 h of fermentation, a consumption of 15% of total organic carbon and 10% of nitrogen was observed. The crude enzymatic extract kept about 80% of its initial activity after 1848 h under low temperatures. An increase of PME activity was observed after incubation at high temperatures. The residual activity of the extracts after 1728 h of incubation was about 95% for all tested pH values (5, 7, 9 and 11). The application of 0.5% (v/v) of PME crude extract for clarification of peach juice showed a reduction on the viscosity (7.20%) and turbidity (14.11%). Keywords: Penicillium brasilianum , pectin-methyl-esterase, experimental design, pectin-methyl-esterase (PME). African Journal of Biotechnology Vol. 12(40), pp. 5886-5896