Study of ultrasound-promoted, lipase-catalyzed synthesis of fructose ester

Abstract

The effect of low energy ultrasound in biochemistry and biotechnology has attracted great attention in recent years. It can enhance substrate dissolution and improve mass transfer within and outside of a cell, both of which are beneficial to the synthesis of fructose ester. Here we describe the experimental study of the effect of ultrasounds of different intensity on the lipase-catalyzed synthesis of fructose ester in the solvent butanone. The results were compared with control reactions performed with no ultrasound. High performance liquid chromatography (HPLC) and thin layer chromatography (TLC) were used for qualitative and quantitative analyses. The results show the following: 1) the concentration of monoester and diester increased with the reaction time, either with or without ultrasonic irradiation. Low energy ultrasound accelerated the reaction due to the effect of ultrasonic steady cavitations, and high energy ultrasound was not beneficial to the reaction. 2) The application of ultrasound played an important role in our lipase-catalyzed reaction. It decreased reaction time as compared to a reaction without ultrasound that resulted in the same yield, increased reaction rate, and enhanced the amount of fructose ester produced. When the frequency was 10 kHz and sound intensity was 0.16 W%m -2 , the concentration of ester was twofold more than without ultrasonic irradiation after a reaction time of up to 12 h. With the proper ultrasonic parameters, the overall concentration of production appeared to increase exponentially with the reaction time. 3) Ultrasound had little effect on the initial reaction rate, and continuous ultrasonic irradiation was favorable for the reaction. The longer the reaction continued, the more obvious the effects of the ultrasound became in our experiments.

Enzyme-catalyzed production of biodiesel by ultrasound-assisted ethanolysis of soybean oil in solvent-free system

“…Low intensities of ultrasound enhance the movement through the medium, favoring the flux of reactants to the active sites of the enzyme, favoring the reaction. However, the intensity and/ or the time of irradiation can lead to the enzyme inactivation by cavitational collapses [33].…”

Accelerating Enzymatic Catalysis Using Vortex Fluidics

“…A similar lag period before rate acceleration has been described previously for ultrasound-accelerated enzyme acceleration. [13] …”

Ultrasound-assisted biosynthesis of novel methotrexate-conjugates

“…the steady cavitation corrosion of ultrasound which might cause the enzyme molecule or cell granulation around it to be shared by microstreaming [12], improving the mass transfer inside or outside of the enzyme. The final reason is related with the enzyme structure which in the presence of ultrasound become more flexible, and thus, may shift into its active configuration [18]. Considering that different enzymes have different stereo-configurations for the same ultrasonic parameters adopted, different enzyme behavior was observed for both immobilized CALB and liquid lipase.…”

“…The enzymatic catalysis assisted by ultrasound has been proved to overcome some of the negative aspects associated with the reactional processes using lipases. The presence of ultrasound improves the enzymatic reactions comparing with the reactions performed its absence, by improving the mass transfer, enhancing the substrate dissolution, minimizing the reactional time, increasing the reaction yield and the chemo-, regio-and stereo selectivities [16][17][18]. An example, is reported by Gumel et al, that used Lipase from Candida antarctica B for the polymerization of ε-caprolactone to poly-6-hydroxyhexanoate by ring opening method.…”