Selective Ethanolysis of Fish Oil Catalyzed by Immobilized Lipases

Abstract

Selective ethanolysis of fish oil was catalyzed by immobilized lipases and their derivatives in organic media. Lipases from Candida antarctica B (CALB), Thermomyces lanuginosa (TLL) and Rhizomucor miehei (RML) were studied. The three lipases were immobilized by anion exchange and hydrophobic adsorption. The discrimination between the ethyl ester of eicosapentaenoic acid (EE-EPA) and the ethyl ester of docosahexaenoic acid (EE-DHA) depends on the lipase, the immobilization support, the physico-chemical modifications of the immobilized lipase derivatives and on the solvents used. TLL and RML were much more selective than CALB. EE-EPA is released 20-fold faster than EE-DHA when ethanolysis was catalyzed, in cyclohexane, by TLL hydrophobically adsorbed on Sepabeads C18. The selectivity and stability of the different derivatives in these polar organic solvents were further improved after physico-chemical modification. The best results for activity-selectivity-stability were obtained in cyclohexane for TLL adsorbed on Sepabeads C18 and further modified via solid-phase physical modification with a polyethylenimine polymer. In this case, the initial selectivity was higher than 20, and a 80 % of EPA was released as ethyl ester after 3 h at 25°C. At this conversion, mixtures of ethyl esters highly enriched in the ethyl ester of EPA with less than 5 % of the EE-DHA were obtained. TLL derivatives remained fully active after incubation for 24 h in anhydrous solvents.

Beauveria bassiana Lipase A expressed in Komagataella (Pichia) pastoris with potential for biodiesel catalysis

“…Lipases from different sources, even when immobilized on the same type of support, may present different selectivity. In a previous ethanolysis study [49], the authors obtained different degrees of selectivity (EPA/DHA) for CALB (3.0), TLL (29.0) and RML (13.0), immobilized on C18-Sep. Catalyst selectivity was influenced by the nature of the support used for immobilization, where TLL-C18 was more specific than TLL-Duolite and the selectivity were 29 and 12, respectively ( Moreno-Perez et al, 2014 ). It is noteworthy that the TLL also showed differences in selectivity when immobilized in the same supports used for BbLA.…”

“…The catalytic activity assay, modified from Moreno-Perez et al (2014) , used a spectrophotometer with a thermostated cell and continuous magnetic stirring (500 rpm) for 2 min. Reactions were initialized by mixing 0.1 mL of the soluble BbLA or its immobilized preparations (suspension) were added to 2.0 mL of the p NPB solution (2.0 mM p -nitrophenyl butyrate ( p NPB) in 0.05% Triton X-100 and 25 mM sodium phosphate at pH 7.0) at 40°C.…”

“…Ethyl ester synthesis by BbLA was performed as described by Moreno-Perez et al (2014) . First, 0.26 g of dried immobilized lipase was added to the substrate solution containing 0.623 mmol of sardine oil and 6.2 mmol of ethanol dissolved in 4.11 mL cyclohexane.…”

Immobilization Effects on the Catalytic Properties of Two Fusarium Verticillioides Lipases: Stability, Hydrolysis, Transesterification and Enantioselectivity Improvement

“…This result was significant to demonstrate the ability to synthesize esters from oils (important feature for biodiesel production). However, it was lower when compared to the selectivity of commercial lipase from Thermomuyces lanuginosus, Candida albicans B and Rhizomucor miehei (Novo Nordish, Denmark) [33].…”

Immobilization of Moniliella spathulata R25L270 Lipase on Ionic, Hydrophobic and Covalent Supports: Functional Properties and Hydrolysis of Sardine Oil

“…They are usually used in an organic medium catalyzing esterification, transesterification and interesterification reactions [ 6 , 7 ]. An important application of lipases is to obtain polyunsaturated fatty acids (PUFA) via enzymatic hydrolysis of fish oil, which is rich in cis -5,8,11,15,17-eicosapentaenoic acid (EPA) and cis -4,7,10,13,16,19-docosahexaenoic acid (DHA) [ 8 , 9 , 10 , 11 , 12 , 13 ]. The use of enzymes may be favorable compared to chemical processes by being more specific, decreasing steps in production and reducing the generation of undesirable compounds [ 8 , 9 , 10 , 11 , 12 ].…”