The Microwave-assisted Synthesis of Polyethersulfone (PES) as A Matrix in Immobilization of Candida antarctica Lipase B (Cal-B)

Abstract

Candida antarctica lipase B (Cal-B) has been widely used in the hydrolysis reaction. However, it has some weaknesses, such as: forming of the heavy emulsion during the process, which is difficult to resolve and has no reusability. Therefore, it needs to be immobilized into a suitable matrix. One of the suitable supporting materials is polyethersulfone (PES) and its synthesis becames the objective of this paper. The PES was synthesized via a polycondensation reaction between hydroquinone and 4,4'-dichlorodiphenylsulfonein N-methylpyrrolidone (NMP) as solvent using Microwave Assisted Organic Synthesis (MAOS) method at170 °C for 66 minutes using an irradiation power of 300 watt. The synthesized PES was characterized by FTIR and 1 H-NMR (500 MHz, DMSO-d6). Then the PES membrane was prepared from 20% of the optimized mixtures of PES, PSf (polysulfone), and PEG (polyethylene glycol) dissolved in 80% NMP. The Cal-B was immobilized on the PES membrane by mixing it in a shaker at 30 °C and 100 rpm for 24 h using phosphate buffered saline (PBS). The identification of the immobilized Cal-B was done by using FTIR-ATR spectroscopy and SEM micrographs. The results of Lowry assay showed that the 'Cal-B immobilized' blended-membrane has a loading capacity of 91 mg/cm 2 in a membrane surface area of 17.34 cm 2 . In this work, the activity of immobilized Cal-B was twice higher than the native enzyme in p-NP (p-Nitrophenolpalmitate) hydrolyzing. The results indicated that the synthesized PES showed a good performance when used as a matrix in the immobilization of Cal-B.

Bioinspired Lipase Immobilized Membrane for Improving Hesperidin Lipophilization

“…The functional group changes of the new membrane, CAL-B@PES, CAL-B@PDA/PES and GA/CAL-B@PDA/PES were analyzed by FTIR spectrum ( Figure 3 ). In comparison with the new membrane, CAL-B@PES had a new peak value at 3390 cm −1 , which belonged to the stretching vibration of -NH and -OH groups, confirming the successful immobilization of CAL-B on the membrane [ 13 ]. Furthermore, compared with CAL-B@PES, the peak stretching vibration of PDA-coated CAL-B@PDA/PES enhanced at 3390 cm −1 , and some new bands appeared at the range of -CH 2 (2930 cm −1 ), which provided evidence for the successful PDA coating on the new membrane [ 37 ].…”

“…Lipase, with high selectivity and specificity, is regarded as the desirable choice for the acylation reaction [ 10 , 11 ]. Nevertheless, the free lipase cannot be recycled after the acylation reaction, making continuous production difficult, and resulting in a high operating cost [ 12 , 13 , 14 ]. To overcome the above stated disadvantages during the biocatalysis process, bioinspired lipase immobilized membranes (BLIMs), which immobilize lipase on the membrane surface or into the membrane pore, can combine catalysis and separation into one step, as well as to achieve lipase recycling, greatly improving the enzymatic esterification efficiency [ 15 ].…”