Novelty of Penicillium camembertii Lipase Supported on Glutaraldehyde Activated-SBA-15 Mesoporous Silica for Mono-Esterification of Bioglycerol in Non-Aqueous Media

Hexagonal mesoporous type silica SBA-15 with pore sizes in the range 5.0–8.3 nm was synthesized using non-ionic triblock copolymer and characterized by Accelerated Surface Area Porosimetry (ASAP), FT-IR spectroscopy, X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). Different lipases were immobilized in glutaraldehyde activated mesoporous SBA-15 support. The resulting supported enzymes were shown to be active and stable catalysts for esterification of glycerol with oleic acid to produce monoglyceride (MG) which is commonly used in food industry. Various parameters were studied systematically to study kinetics. MG Synthesis using enzymatic process is an environmentally friendly approach. Enzyme immobilized on SBA-15 showed the best stability and catalytic activity in organic solvents. Out of various lipases studied penicillium camembertii (Lipase G) produced MG efficiently at low temperature. Reusability was studied on immobilized enzymes. Immobilized lipase maintained 90 % of its esterification activity in non-aqueous media even after 4 cycles of use. The selectivity of Lipase G is found to be 98 % for monoacylglyceride.

Immobilization of a Commercial Lipase from Penicillium camembertii (Lipase G) by Different Strategies

The objective of this work was to select the most suitable procedure to immobilize lipase from Penicillium camembertii (Lipase G). Different techniques and supports were evaluated, including physical adsorption on hydrophobic supports octyl-agarose, poly(hydroxybutyrate) and Amberlite resin XAD-4; ionic adsorption on the anionic exchange resin MANAE-agarose and covalent attachment on glyoxyl-agarose, MANAE-agarose cross-linked with glutaraldehyde, MANAE-agarose-glutaraldehyde, and epoxy-silica-polyvinyl alcohol composite. Among the tested protocols, the highest hydrolytic activity (128.2 ± 8.10 IU·g−1 of support) was achieved when the lipase was immobilized on epoxy-SiO2-PVA using hexane as coupling medium. Lipase immobilized by ionic adsorption on MANAE-agarose also gave satisfactory result, attaining 55.6 ± 2.60 IU·g−1 of support. In this procedure, the maximum loading of immobilized enzyme was 9.3 mg·g−1 of gel, and the highest activity (68.8 ± 2.70 IU·g−1 of support) was obtained when 20 mg of protein·g−1 was offered. Immobilization carried out in aqueous medium by physical adsorption on hydrophobic supports and covalent attachment on MANAE-agarose-glutaraldehyde and glyoxyl-agarose was shown to be unfeasible for Lipase G. Thermal stability tests revealed that the immobilized derivative on epoxy-SiO2-PVA composite using hexane as coupling medium had a slight higher thermal stability than the free lipase.