Ultrasonic pretreatment in lipase-catalyzed synthesis of structured lipids with high 1,3-dioleoyl-2-palmitoylglycerol content

Abstract

Production of structured lipid 1,3-dioleoyl-2-palmitoylglycerol (OPO), from tripalmitin (PPP) and oleic acid (OA) using lipases and ultrasonic pretreatment was conducted. Factors influencing both the ultrasonic conditions and enzymatic reaction were investigated. Optimum conditions could be attained with 6 min pretreatment time, 50% ultrasonic power, 3 s/9 s (work/pause) cycle of ultrasonic pulse, 1:8 PPP/OA molar ratio, 12% enzyme dosage and 50 °C temperature of. At the optimum conditions, the OPO yield of 51.8% could be achieved in 4h. Studies showed that the OPO content increased to 35.9% in 1h with ultrasonic pretreatment, in comparison to 4h without ultrasonic pretreatment. Reuse of Lipozyme RM IM for 10 cycles under ultrasonic irradiation did not cause essential damage to its lipase activity. Reaction kinetic model fitted well with the proposed Ping-Pong mechanism. The apparent kinetic constant (Vm'/K₂) of ultrasound pretreatment reaction was 2.52 times higher than the conventional mechanical stirring, indicating that ultrasound pretreatment enhanced the substrates affinity to the enzyme. This study confirmed that ultrasonic pretreatment was more efficient in OPO production than conventional mechanical agitation.

Enzymolysis kinetics, thermodynamics and model of porcine cerebral protein with single-frequency countercurrent and pulsed ultrasound-assisted processing

“…The decrease in k us was due to the decrease of gas solubility in the bulk of fluid and a lower value for the ratio of specific heats of water vapor; the increase of equilibrium vapor pressure of the system and the formed cavitation bubbles as the temperature increased [35]. The effect of ultrasound appeared to be weak at higher temperatures, which was in agreement with results reported by Liu et al [36].…”

Enzyme-Catalyzed Synthesis and Kinetics of Ultrasonic-Assisted Methanolysis of Waste Choice White Grease for Fatty Acid Methyl Ester Production

“…The concentrations of the substrates and FAME at different times were determined experimentally starting with 10 g of waste CWG and varied methanol amounts of 1.51, 2.27, and 3.03 g to obtain molar ratios of methanol/ CWG of 1:4, 1:6, and 1:8, respectively. The effects of processing parameters, such as ultrasonic amplitudes (30,35,40,45, and 50%) at varied reaction times (5,10,15,20,25, and 30 min), on the reaction rates of enzyme-catalyzed transesterification of waste CWG were investigated. This was achieved by fitting the reaction rate differential equations generated on the basis of the Ping Pong Bi Bi mechanism to the experimental data.…”

Ultrasound effects on the activity of Aspergillus niger lipases in their application in dairy wastewater treatment

“…In the case of lipases, we did not find any work that reported the effect of ultrasound on the enzyme individually in order to improve its activity; we only found some studies reporting the use of ultrasound to treat the whole of the enzyme and substrate during enzyme reaction to improve its performance, such as in the work presented by Liu et al (2015).…”

“…The use of ultrasound as a pretreatment has led to significant improvements in the apparent rate constant of lipid production reaction. 1,3-Dioleoyl-2-palmitoylglycerol from tripalmitin and oleic acid showed the best performance improvement of the enzyme and the affinity between the substrate and enzyme (Liu et al, 2015). The results presented by Ramón et al (2015) demonstrate the potential use of ultrasound on enzymatic hydrolytic reaction, as there was an increase of 32% in the amount of fermentable sugars when this technology was used in association with the treatment temperature.…”

“…The use of ultrasound as a pretreatment has led to significant improvements in the apparent rate constant of lipid production reaction. 1,3‐Dioleoyl‐2‐palmitoylglycerol from tripalmitin and oleic acid showed the best performance improvement of the enzyme and the affinity between the substrate and enzyme (Liu et al., ). The results presented by Ramón et al.…”