Thermodynamic properties of the enzymatic hydrolysis of sunflower oil in high‐pressure reactors

Abstract

On the basis of our previous results, where optimal conditions for the lipase-catalyzed hydrolysis of sunflower oil in a high-pressure batch stirred tank reactor were determined, some thermodynamic and kinetic properties of lipase preparation Lipolase 100T (Aspergillus niger lipase) were established. Activation energy (32.7 kJ/mol) was determined from an Arrhenius plot. Activity of the Lipolase 100T increased between 35 and 50°C, but with further temperature increase thermal deactivation occurred. The thermal deactivation rate constant was 0.40, and the deactivation enthalpy was 123.0 kJ/mol. Because of the desirability of continuous applications of enzyme-catalyzed reactions, a high-pressure continuous flat-shape membrane reactor (HP CFSMR) was designed. Hydrolysis of sunflower oil in this reactor was performed. Maximal conversion in the HP CFSMR was achieved after 1 h. A polysulfone membrane was successfully used as a separation unit, and the highest conversion of FFA was determined at 50°C, 200 bar, and a flow rate for substrates of 0.1 mL/min (each).Paper no. J10347 in JAOCS 80, 785-788 (August 2003).

A Review on the Effects of Supercritical Carbon Dioxide on Enzyme Activity

“…Because lipases were found to be stable in SC-CO 2 , a lipase-catalyzed hydrolysis of sunflower oil was performed in two kinds of high-pressure reactors in this medium, a high-pressure batch stirredtank reactor (HP BSTR [ 62 ]) and a high-pressure continuous flat-shape membrane reactor (HP CFSMR [ 63 ]), in this medium. The reaction rates of enzyme-catalyzed reactions were higher than those of the conventional reactions.…”

Biocatalysis in Supercritical Fluids, in Fluorous Solvents, and under Solvent-Free Conditions

“…It is suggested that the dry compressed CO 2 stabilizes the protein structure of NZ 435 65 or that there is a faster mass transfer of the substrate to the active site of the enzyme plus higher reaction rates at elevated temperatures . In contrast, Primozic et al demonstrated the deactivation of lipolase 100T (L 100T) above 50 °C . They suggest that this is due to the denaturation of the enzyme.…”

“…66 In contrast, Primozic et al demonstrated the deactivation of lipolase 100T (L 100T) above 50 °C. 67 They suggest that this is due to the denaturation of the enzyme. For the esterification of oleic acid, LZ gains activity from 40 to 60 °C but is thermally denatured at 80 °C, 66 and this is in agreement with the observations of Habulin et al 68 Other reports suggest an increase in enzyme thermal stability in nc-propane as compared to that in water; for example, the optimum reaction temperature for PPL in water is 40 °C, but in nc-propane, the optimum temperature is 50 °C.…”

Plant Products for Pharmacology: Application of Enzymes in Their Transformations

“…[ 118 ] studied the thermodynamic and kinetic properties of the immobilized lipase from Aspergillus niger (Lipolase 100T), and used this enzyme for catalysis of hydrolysis of sunflower oil in supercritical carbon dioxide. Employing a high-pressure continuous flat-shape membrane reactor, they achieved maximum conversion after 1 hour of the reaction at 50 °C, 90 MPa, and at a flow rate for substrates of 0.1 mL/min, improved during following investigation [ 119 , 120 ].…”