Immobilization of an Antarctic Pseudomonas AMS8 Lipase for Low Temperature Ethyl Hexanoate Synthesis

Abstract

The demand for synthetic flavor ester is high, especially in the food, beverage, and cosmetic and pharmaceutical industries. It is derived from the reaction between a short-chain fatty acid and alcohol. Lipases from Antarctic bacteria have gained huge interest in the industry due to its ability react at low temperatures. The use of immobilization enzymes is one of the methods that can improve the stability of the enzyme. The current work encompasses the low temperature enzymatic synthesis of ethyl hexanoate by direct esterification of ethanol with hexanoic acid in a toluene and solvent-free system. The effects of various reaction parameters such as the organic solvent, temperature, time, substrate, substrate ratio and concentration, enzyme concentration on ethyl hexanoate synthesis were tested. Several matrices were used for immobilization and comparisons of the efficiency of immobilized enzyme with free enzyme in the synthesis of flavor ester were conducted. Ester production was optimally synthesized at 20 • C in both systems-immobilized and free enzyme. A 69% ester conversion rate was achieved after a two-hour incubation in toluene, compared to 47% in a solvent-free system for free enzyme. Immobilized AMS8 lipase showed a higher conversion of ester in toluene with respect to free-solvents, from 80% to 59%, respectively. Immobilized enzymes showed enhancement to the stability of the enzyme in the presence of the organic solvent. The development of AMS8 lipase as an immobilized biocatalyst demonstrates great potential as a cost-effective enzyme for biocatalysis and biotransformation in the food industry.

Production of Cold-Active Lipase by Free and Immobilized Marine Bacillus cereus HSS: Application in Wastewater Treatment

“…These findings were consistent with previous studies, where lower fermentation temperature had a positive effect on lipase production (Anasontzis et al, 2014) Among the tested range of temperature (15–35°C), the optimum temperature for cold-active lipase production by Pichia lynferdii NRRL Y-7723 was 20°C as previously reported (Park et al, 2013). The effect of temperature on enzyme activity is attributed to its effect on stability, rate of the reaction, substrate solubility as well as direct influence on esterification reaction (Musa et al, 2018). …”

“…The productivity obtained by the immobilized cells on sponge was considerably higher than the free cells. A comparative study indicated that the dramatic variation and the efficiency of an immobilization process rely on the support used (Musa et al, 2018). Thus, cells adsorbed on sponge (Figure 8C) were chosen to complete the study, when these immobilized cells were reused for five successive cycles.…”

Effects of Lid 1 Mutagenesis on Lid Displacement, Catalytic Performances and Thermostability of Cold-active Pseudomonas AMS8 Lipase in Toluene

“…This yield was higher than reactions without organic solvents (35%). This means, the conversion percentage of ethyl hexanoate was significantly improved in the presence of toluene compared to other organic solvents and solvent-free system [ 52 ]. Our views in improving the esterification yield is by achieving higher solvent-accessibility via lid 1 surface engineering.…”

Determination the Lipase Activity of Staphylococcus sp. Strain Isolated from Clinical Specimens

“…also the present study suggest that the production of lipase at high temperature due to that temperature stimuli the secretion 23 . The study of 31 reported that the effect of temperature on enzyme activity is attributed to its effect on stability, rate of the reaction, substrate solubility as well as direct influence on esterification reaction. The results in the present study agree with 9,32 it reported the optimum incubation temperature for lipase production at 37°C of Pseudomonas gessardii and certain species of Pseudomonas.…”