Recovery of pectinases from Aspergillus niger using aqueous two-phase systems / Recuperação de pectinases de Aspergillus niger usando sistemas aquosos bifásicos

This work aimed to study the purification of pectinases by aqueous two-phase systems (ATPS). The crude enzymatic extract was produced by Aspergillus niger ATCC 9642 and contained exo-polygalacturonase (exo-PG), pectinmethylesterase (PME) and pectin lyase (PMGL). The ATPS systems tested consisted in the combinations of polyethylene glycol (PEG) and potassium phosphate and sodium citrate, alcohol (ethanol, n-propanol and isopropanol) and salt (ammonium sulfate, potassium phosphate and sodium citrate). The experiments showed higher recoveries using ATPS system - PEG/phosphate for the exo-PG were using 16% PEG 4.0 kDa/4.8% NaCl and 16% PEG 1.5 kDa/without NaCl, obtaining purification factors (PF) of 1.37 and 1.21 times and recovery (R) of 49 and 59%, respectively. However, for the enzymes PME and PMGL were of 4.8 and 4.7 fold and 478 and 241%, respectively. When used ATPS system - PEG/sodium citrate the best PF were of 2.4, 7.85 and 5.7 and R of 100, 331 and 239% for exo-PG, PME and PMGL, respectively. The ATPS system is an alternative and efficient method for the recovery and/or purification of pectinases. This work aimed to study the purification of pectinases by aqueous two-phase systems (ATPS). The crude enzymatic extract was produced by Aspergillus niger ATCC 9642 and contained exo-polygalacturonase (exo-PG), pectinmethylesterase (PME) and pectin lyase (PMGL). The ATPS systems tested consisted in the combinations of polyethylene glycol (PEG) and potassium phosphate and sodium citrate, alcohol (ethanol, n-propanol and isopropanol) and salt (ammonium sulfate, potassium phosphate and sodium citrate). The experiments showed higher recoveries using ATPS system - PEG/phosphate for the exo-PG were using 16% PEG 4.0 kDa/4.8% NaCl and 16% PEG 1.5 kDa/without NaCl, obtaining purification factors (PF) of 1.37 and 1.21 times and recovery (R) of 49 and 59%, respectively. However, for the enzymes PME and PMGL were of 4.8 and 4.7 fold and 478 and 241%, respectively. When used ATPS system - PEG/sodium citrate the best PF were of 2.4, 7.85 and 5.7 and R of 100, 331 and 239% for exo-PG, PME and PMGL, respectively. The ATPS system is an alternative and efficient method for the recovery and/or purification of pectinases. This work aimed to study the purification of pectinases by aqueous two-phase systems (ATPS). The crude enzymatic extract was produced by Aspergillus niger ATCC 9642 and contained exo-polygalacturonase (exo-PG), pectinmethylesterase (PME) and pectin lyase (PMGL). The ATPS systems tested consisted in the combinations of polyethylene glycol (PEG) and potassium phosphate and sodium citrate, alcohol (ethanol, n-propanol and isopropanol) and salt (ammonium sulfate, potassium phosphate and sodium citrate). The experiments showed higher recoveries using ATPS system - PEG/phosphate for the exo-PG were using 16% PEG 4.0 kDa/4.8% NaCl and 16% PEG 1.5 kDa/without NaCl, obtaining purification factors (PF) of 1.37 and 1.21 times and recovery (R) of 49 and 59%, respectively. However, for the enzymes PME and PMGL were of 4.8 and 4.7 fold and 478 and 241%, respectively. When used ATPS system - PEG/sodium citrate the best PF were of 2.4, 7.85 and 5.7 and R of 100, 331 and 239% for exo-PG, PME and PMGL, respectively. The ATPS system is an alternative and efficient method for the recovery and/or purification of pectinases

Swine manure digestate treatment using electrocoagulation

ABSTRACT Anaerobic biodigestion is an appropriate alternative for the treatment of swine wastewater due to its biogas generation properties and the possibility of its application as a source of energy for heating or electricity. However, digestate can still contain high levels of turbidity, organic carbon and nutrients and must be correctly managed as a biofertilizer, or treated to avoid any impact on the environment. Considering this, electrocoagulation (EC) shows promise as a technology because of its ease of handling and high efficiency in effluent remediation. This study aimed to evaluate the performance of EC in a batch system in the treatment of swine wastewater digestate. The wastewater used in the treatment was sampled from a 10 m3 biodigestor effluent (digestate) located at Concórdia, Santa Catarina, Brazil. A batch-scale experiment was carried out to evaluate the following two variables: electrode distance (ED) and voltage applied (V). The removal efficiency levels (%) for the best operational condition (2 cm, 5 V) after 30 min were: 97 %, 98 %, 77 % and 10 % for color, turbidity, total organic carbon (TOC) and total nitrogen (TN), respectively. The EC batch system produced efficient results, underlining its promise as an alternative to be applied in the treatment of digestate

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

This study reports the optimization of geranyl butanoate production by esterification of geraniol and butanoic acid in a solvent-free system using two immobilized lipases as catalyst. The operating conditions that optimized geranyl butanoate production were determined to be 40 °C, a geraniol to butanoic acid molar ratio of 3:1, 150 rpm, 5 wt% of enzyme, and 1 h of reaction, which resulted in a reaction conversion of about 97% for Novozyme 435. When homemade Novozyme NZL-102-LYO-HQ (Cal-B) immobilized in polyurethane foam was used as catalyst, the experimental conditions of an alcohol to acid molar ratio of 5:1, 70 °C, 150 rpm, 5 wt% of enzyme, and 1 h of reaction gave a conversion of 95%. New experimental data on enzymatic esterification of geraniol and butanoic acid for geranyl butanoate production are reported in this work, showing that the technique is promising for overcoming the well-known drawbacks of the chemical-catalyzed route

Purification of inulinases by changing the ionic strength of the medium and precipitation with alcohols

ABSTRACT The present study evaluated the purification of inulinase by changing the ionic strength of the medium by addition of NaCl and CaCl2 followed by precipitation with n-propyl alcohol or iso-propyl alcohol. The effects of the concentration of alcohols and the rate of addition of alcohols in the crude extract on the purification yield and purification factor were evaluated. Precipitation caused an activation of enzyme and allowed purification factors up to 2.4-fold for both alcohols. The purification factor was affected positively by the modification of the ionic strength of the medium to 0.5 mol.L-1 NaCl before precipitation with the alcohol (n-propyl or iso-propyl). A purification factor of 4.8-fold and an enzyme yield of 78.1 % could be achieved by the addition of 0.5 mol.L-1 of NaCl to the crude extract, followed by the precipitation with 50 % (v/v) of n-propyl alcohol, added at a flow rate of 19.9 mL/min