Efficient substrate accessibility of cross-linked levanase aggregates using dialdehyde starch as a macromolecular cross-linker

Protein Interaction Studies of Cross-Linked Endolevanase Aggregates From Bacillus Lehensis G1

“…Enzyme (rlevblg1) expression, purification and development of CLEAs was performed using the protocol of Abd Rahman, Jaafar [15] with some modifications. For enzyme precipitation, 60% of ammonium sulphate was added to 0.4 mg/mL of the enzyme with 200 rpm orbital stirring at 4 °C for 1 h. The aggregated enzyme was then cross-linked by the addition of the optimal concentration (0.8% (v/v)) of the macromolecular cross-linker [15] (cellulose, chitosan, dialdehyde-starch (DAS), dextran, pectin, polyethylene glycol 8000 (PEG8000) and sodium alginate) in total volume of 1 mL with constant agitation of 200 rpm at 4 °C for 1 h. The enzyme assay [20] and recovery activity of immobilized enzyme were calculated from equation 1 and 2, respectively:…”

“…Therefore, computational estimation was expected to facilitate the finding of the suitable macromolecular cross-linker for endolevanase from Bacillus lehensis G1 (rlevblg1). Previously, rlevblg1 was immobilized via CLEAs using GA [14] and dialdehydestarch (DAS) [15] serving as cross-linking agents. Compared to GA, the larger size of DAS helped in decreasing the compactness of CLEAs, improving substrate accessibility and producing longer levantype-fructooligosaccharides (L-FOS).…”

Lipase/tannic acid magnetic hydrogel microspheres and their continuous catalytic application

“…However, study on the immobilization of lipases on polyacrylamide hydrogel microbeads is usually realized by hydrogen-bond interactions, which are weak and lead to the shedding of the lipase during continuous production. [18][19][20] Chemical covalent bonds [21][22][23][24] could make the lipase more firmly immobilized on the carrier. A common chemical method to immobilize enzymes is to use glutaraldehyde [25][26][27] to connect the carrier with the enzyme molecule.…”

Magnetic cross-linked enzyme aggregate based on ionic liquid modification as a novel immobilized biocatalyst for phytosterol esterification

“…11 Firstly, the enzyme was purified by forming protein precipitates, then amino groups of enzyme proteins were crosslinked directly by crosslinking agents (e.g., glutaraldehyde, polyacetal, and dextran) to quickly form low-cost CLEAs. 12,13 Carrier-free CLEA technology due to its low cost and simple preparation process has been widely used to immobilize various enzymes, such as peroxidases, 14 lipases, 15 and proteases. 16 However, CLEAs also have some problems, such as low mechanical strength due to the absence of a carrier, difficulty in recovery after reaction due to nanoscale particles of CLEAs, and difficulty in controlling the degree of crosslinking.…”