Synthesis of symmetrical structured triglycerides via a bottom-up process

The synthesis of symmetrical structured triglycerides (STG) through a bottom-up approach was previously shown to produce 1,3-dioleoyl-2-palmitoyl glycerol in significant quantities. This solvent-free lipase-catalyzed process, consisting of a low-temperature (40 °C) esterification step with glycerol dosing followed by a high-temperature (60 °C) esterification step, was further investigated in the production of symmetrical medium-and-long-chain triglycerides (MLCT). By replacing oleic acid with capric acid in the first step or the palmitic acid by either capric acid or lauric acid in the second step, the effects of free fatty chain length and sequence of fatty acid addition on STG production were established. These produced 1,3-dicaproyl-2-oleoyl glycerol, 1,3-dioleoyl-2-caproyl glycerol, and 1,3-dioleoyl-2-lauroyl glycerol at concentrations of 36.98 g, 36.77 g, and 37.08 g per 100 g of triglycerides respectively after 72 h at an overall FFA1:FFA2:Glycerol of 2:1:1 and 4 g Novozyme 435 per 100 g reactants, without the purification of intermediates and products. The sequence of fatty acid addition had the most significant effect as purer STG products can be obtained when the medium chain fatty acid is introduced in the first step. As the process was carried out without solvents, the STG produced are appropriate for functional food or nutraceutical applications.

Virus-templated magnetic composite hydrogels for surface immobilization of mimic-free-lipase

M13 virus-templated magnetic composite hydrogels were designed for surface immobilization of mimic-free-lipases, achieving high enzyme loading amount, high activity recovery yield, free-enzyme-equal activity, less MNPs and enhanced stability.

Conversion of waste cooking oil by rhodococcal lipase immobilized in gellan gum

Recently, the application of lipase enzyme as biocatalyst in the conversion of waste cooking oil (WCO) to free fatty acids and glycerol has been trending well. Therefore, the present study attempts to use WCO which is found in abundance in Malaysia as the substrate for halal microbial lipase conversion to glycerol which can be exploited in the food industry. The workability of free lipase for WCO conversion, however suffers severely due to potential denaturation of the enzyme and extended reaction time. Thus, this study embraced the immobilization method to encapsulate crude lipase extracted from Rhodococcus pyridinivorans strain UCC 0009 in gellan gum and calcium alginate, respectively and compared their ability for WCO conversion to free crude lipase. The gellan gum and calcium alginate-immobilized crude lipase evidently exhibited greater WCO conversion, demonstrating 2.18-fold and 1.61-fold enhanced lipase activity, respectively in comparison to free crude lipase. The repeated reuse of the gellan gum-immobilized crude lipase maintained reasonable lipase activity for 9 cycles, retaining an average 85 % WCO conversion for the first seven cycles and 67 % conversion in the subsequent batches. Thus, the immobilized halal lipase can be foreseen as a green substitute to chemical catalyst for WCO conversion which meets the worldwide demand for clean technologies.

Improved biodiesel from palm oil using lipase immobilized calcium alginate and Irvingia gabonensis matrices

Background Lipase is an important microbial enzyme and biocatalyst in biodiesel production. The study investigated fuel properties of biodiesel produced from palm oil (PO) using lipase immobilized on Irvingia gabonensis and calcium alginate. Results Biodiesel yield from PO using free and immobilized lipases was highest at 35 °C and pH 7, with product yield using calcium alginate-immobilized lipase, CAIL (94.42, 96.9%) higher than using Irvingia gabonensis-immobilized lipase, IGIL (92.54, 95.8%). Biodiesel produced using immobilized lipases had similar pour point, cloud point, and kinematic viscosity, and they possessed improved fuel properties compared to free lipase biodiesel in terms of densities at 15 °C and flash point. Pour points, flash point, and kinematic viscosity of biodiesel produced using CAIL and IGIL met American and European Standards but density at 15 °C and cloud points are below both standards. CAIL and IGIL biodiesel had similar fatty acid methyl ester (FAME) compounds and consisted more of unsaturated fatty acids (hexadecanoate, 9-octadecenoate, octadecanoate, dodecanoate, and 9,12-octadeca-dienoate) than obtained in biodiesel from free lipase. IGIL and CAIL were re-used in 8 and 12 cycles respectively, with > 90% biodiesel yield achieved in four and 11 cycles. Conclusions The study showed that lipase immobilized on Irvingia gabenensis and calcium alginate and used in biodiesel production retained high enzyme activity and biodiesel yield in repeated cycles.