Production of heat-sensitive monoacylglycerols by enzymatic glycerolysis in tert -pentanol: Process optimization by response surface methodology

Encapsulation of lipases by nucleotide/metal ion coordination polymers: enzymatic properties and their applications in glycerolysis and esterification studies

BACKGROUND

In the present study, lipases of TLL (lipase from Thermomyces lanuginosus), AOL (lipase from Aspergillus oryzae), RML (lipase from Rhizomucor miehei), BCL (lipase from Burkholderia cepacia), CALA (Candida antarctica lipase A) and LU (Lecitase® Ultra) were encapsulated into nucleotide-hybrid metal coordination polymers (CPs). Enzyme concentration was optimized for encapsulation and the enzymatic properties of the obtained lipases were investigated. In addition, their performance in glycerolysis and esterification was evaluated, and glycerolysis conditions (water content, temperature and time) were optimized.

RESULTS

Hydrolysis activity over 10 000 U g^-1 and activity recovery over 90% were observed from AOL@GMP/Tb, TLL@GMP/Tb and RML@GMP/Tb. GMP/Tb encapsulation (of AOL, TLL, RML and LU) improved their thermostability when incubated in air. The encapsulated lipases exhibited moderate [triacylglycerols (TAG) conversion 30-50%] and considerable glycerolysis activity (TAG conversion over 60%). TAG conversions from 69.37% to 82.35% and diacylglycerols (DAG) contents from 58.62% to 64.88% were obtained from CALA@GMP/metal samples (except for CALA@GMP/Cu). Interestingly, none of the encapsulated lipases initiated the esterification reaction. AOL@GMP/Tb, TLL@GMP/Tb, RML@GMP/Tb and CALA@GMP/Tb showed good reusability in glycerolysis, with 88.80%, 94.67%, 89.85% and 78.16% of their initial glycerolysis activity, respectively, remaining after five cycles of reuse. The relationships between temperature and TAG conversion were LnV₀  = 6.5364-3.7943/T and LnV₀  = 13.8820-6.4684/T for AOL@GMP/Tb and CALA@GMP/Tb, respectively; in addition, their activation energies were 31.55 and 53.78 kJ mol^-1 , respectively.

CONCLUSION

Most of the present encapsulated lipases exhibited moderate and considerable glycerolysis activity. In addition, AOL@GMP/Tb, TLL@GMP/Tb, RML@GMP/Tb and CALA@GMP/Tb exhibited good reusability in glycerolysis reactions and potential in practical applications. © 2022 Society of Chemical Industry.

Meloxicam encapsulated nanostructured colloidal self-assembly for evaluating antitumor and anti-inflammatory efficacy in 3D printed scaffolds

Nanostructured colloidal self-assembly (NCS) is one of the most promising drug delivery carriers in cancer treatment. The present research work aimed towards synthesizing meloxicam (MLX) loaded NCS for its improved circulation half-life and increased cellular internalization. NCS was formulated using glyceryl monoolein, Pluronic® F127, and MLX. Quality by Design experiments with a quadratic model was subjected to optimization of the formulation. The optimized NCS with an average particle size of 185.5 ± 3.02 nm showed higher MLX encapsulation (94.74 ± 3.41%) and sustained release behavior of MLX up to 24 hr. in vitro cytotoxicity of the developed NCS with MCF-7 and MDA-MB-231 cell lines confirmed lower cell viability and a higher rate of cell growth inhibition. This MLX loaded NCS showed dual activity as an antitumor and anti-inflammatory in highly invasive estrogen-dependent MDA-MB-231 cells due to the high expression of cyclooxygenase-2 (COX-2). Besides, an activity of the MLX-NCS was also observed in 3D printed MCF-7 cells. This investigation shows the possible use of MLX-NCS as an efficient cancer drug delivery system with excellent colloidal stability, sustained release of MLX, enhanced antitumor and anti-inflammatory efficacy in 3D printed scaffolds. In contrast to toxicity study in 2D culture, the 3D constructs revealed the activity of the MLX via COX-2 independent mechanism and demonstrated that the relationship between COX-2 expression and antitumor activity of inhibitors is limited. In conclusion, the overall observations and results of this study strengthen the hypothesized development of NCS as a next-generation therapeutics regimen for cancer therapy.

Interesterification of Soybean Oil with Propylene Glycol in Supercritical Carbon Dioxide and Analysis by NMR Spectroscopy

The time course study of high monoester mixtures from soybean oil (HMMS) synthesis, as healthier alternatives to trans food products, in a supercritical CO₂ (SCCO₂) medium with and without enzyme, was investigated. Phosphorous nuclear magnetic resonance (³¹P-NMR) was used to quantify the absolute amount of partially esterified acylglycerols (PEGs). Carbon NMR was utilized to determine the type and position of the fatty acids (FAs) of HMMS. Enzyme and time significantly influenced the synthesis of 1-monoglycerides (1-MGs), 2-MGs, and 1,2-diglycerides (1,2-DGs) in this alcoholysis of soybean oil with 1,2-propanediol, based on high catalytic activity and operational stability of Novozym 435 in SCCO₂ during short reaction time. Results suggest that 4 h is a suitable reaction time for this lipase-catalyzed interesterification (LIE) system for the synthesis of 2-MGs with a yield of 20%. The highest polyunsaturated fatty acid (PUFA) (65%) in the triglyceride (TG) of HMMS was produced after 4 h of reaction. After 6 h of reaction, a high level (20%) of saturated fatty acids (SFAs) was found in the TGs of HMMS, which were distributed between the sn-2 (5%) and sn-1, 3 (15%) positions.

The role of phase behavior in the enzyme catalyzed synthesis of glycerol monolaurate

Partial glycerides such as monoacylglycerides (MAGs) are important functional ingredients with various applications in the cosmetics and food industry.

Production and concentration of monoacylglycerols rich in omega-3 polyunsaturated fatty acids by enzymatic glycerolysis and molecular distillation

Production of monoacylglycerols (MAGs) rich in ω-3 polyunsaturated fatty acids (n-3 PUFAs) was conducted through short path distillation (SPD) of an acylglycerol mixture (containing 67% MAGs) produced by enzymatic glycerolysis of sardine oil with glycerol. A stepwise SPD process in a UIC KDL 5 system (vacuum 10(-3)mbar, feeding flow 1.0 mL/min) was proceeded: the first distillation performed at evaporator temperature (TE) of 110 °C to remove glycerol completely and most of FFAs; and the second distillation at optimized TE 155 °C; resulting in a stream distillate with 91% purity and 94% overall recovery of MAGs. This work also demonstrated that SPD is able to concentrate n-3 PUFAs in MAG form by distilling at proper TE e.g. 125 °C, where n-3 PUFAs are concentrated in the residues. Moreover, this work mapped out a complete processing diagram for scalable production of n-3 PUFAs enriched MAGs as potential food emulsifier and ingredient.

Chemoenzymatic Synthesis of 2-Arachidonoylglycerol, An Endogenous Ligand for Cannabinoid Receptors

A simple and efficient synthesis of 2-arachidonoyl glycerol, an endogenous agonist for cannabinoid receptors was achieved using Novozym 435, immobilized lipase from Candida Antarctica.

A two-stage enzymatic process for synthesis of extremely pure high oleic glycerol monooleate

This paper presents a research interest concentrating on aims to establish a feasible industrial process for enzymatic production of highly pure glycerol monooleate (GMO). The synthesis of high oleic glycerol monooleate by enzymatic glycerolysis of high oleic sunflower oil, using Novozyme 435 as the biocatalyst, in a binary solvent mixture of tert-butanol and tert-pentanol (80/20, v/v), at a lab scale has been studied. A yield of 75.31% monoacylglycerol has been achieved at the first stage. A yield of 93.3% GMO was finally reached after further purification at the second stage. To evaluate the possibility of the process for industrialization, production of GMO was performed at a pilot-plant scale under the correspondingly adjusted conditions. A yield of 68.17% and 93.4% of GMO was obtained, respectively, at the end of the three stages.

Synthesis of monoacylglycerols by enzymatic methods

Monoacylglycerols are non-ionic surfactants widely used in the food industry. They are also important in cosmetic and pharmaceutical industries as drug carriers and for the consistency improvements in creams and lotions. Current process for their production is based on the glycerolysis of natural fats and oils in the presence of inorganic catalysts at temperatures higher than 220 oC. The major drawbacks of this process include high-energy consumption, low yield, and poor product quality. The use of lipases for the monoacylglycerols production offers environmental advantages and a reduction in energy consumption. Besides, the same surfactants prepared by the enzymatic synthesis may be labeled as ?natural?. Recent progress in the application of highly-stable lipases in the organic solvents offers the possibility of employing various methods to the enzyme-catalyzed synthesis of monoacylglycerols, such as selective hydrolysis of fats and oils using 1,3-regiospecific lipases, the esterification of glycerol with fatty acids and the glycerolysis of fats or oils. In this review, different reaction systems such as aqueous-organic two-phase systems, microemulsions and reverse micelles systems, anhydrous organic solvents, solvent-free systems with free or immobilized lipases, as well as the use of two-phase membrane reactor systems are presented. We discuss some of the key factors, such as the control of water content, removing of the products from reaction system, and the effects of solvent on the lipase activity and selectivity, that must be addressed in order to obtain an efficient reaction system with high yields of monoacylglycerols. Engineering of the enzymatic monoacylglycerols synthesis processes requires also optimization of other factors as: molar ratio of substrates, temperature, type of lipase immobilization and supports (if any), reactor design and operating regime.

Process development of continuous glycerolysis in an immobilized enzyme-packed reactor for industrial monoacylglycerol production

Continuous and easily operated glycerolysis was studied in different lipase-packed columns to evaluate the most potential process set-ups for industrial monoacylglycerol (MAG) production. Practical design-related issues such as enzyme-filling degree, required reaction time, mass transfer investigations, and capacity and stability of the enzyme were evaluated. A commercially available immobilized Candida antarctica lipase B was used to catalyze the glycerolysis reaction between glycerol and sunflower oil dissolved in a binary tert-butanol: tert-pentanol medium. Considering easy handling of the enzyme and measured expansion when wetted with a reaction mixture, a filling degree of 52 vol % dry enzymes particles per column volume seemed appropriate. Twenty minutes was required to reach equilibrium conditions with a MAG content of 50-55 wt %. Only insignificant indications of mass transfer limitations were observed. Hence, the commercial lipase seemed adequate to use in its available particle size distribution ranging from 300 to 900 microm. A column length-to-diameter ratio of less than 25 did not interfere with the transfer of the fluid mixture through the column. Under the tested conditions, the enzyme could be active for approximately 92 days before enzyme renewal was needed. This corresponds to a very high enzyme capacity with approximately 2000 L pure MAG produced per kg enzyme.

Evaluation of binary solvent mixtures for efficient monoacylglycerol production by continuous enzymatic glycerolysis

This study was aimed at evaluating different binary solvent mixtures for efficient industrial monoacylglycerol (MAG) production by enzymatic glycerolysis. Of all investigated cases, the binary mixture of tert-butanol:tert-pentanol (TB:TP) 80:20 vol % was the most suitable organic medium for continuous enzymatic glycerolysis, ensuring high MAG formation in a short time, reasonable solvent price, and easy handling during distillation/condensation processing. A minimum solvent dosage of 44-54 wt % of the reaction mixture was necessary to achieve high MAG yields of 47-56 wt %, within 20 min. The melting and boiling points of the TB:TP mixture were estimated to be 7 and 85 degrees C, respectively, using thermodynamic models. These predictions were in good agreement with experimentally determined values. In spite of the high reaction efficiency in the binary TB:TP system, the mixture of glycerol and sunflower oil (containing 97.1% triacylglycerol) yielded surprisingly a liquid/liquid phase split behavior even at high temperatures (>80 degrees C). This in contrast to thermodynamic model calculations suggested full miscibility in all proportions. These findings suggest that enhanced reaction efficiency in organic solvent also depends upon aspects other than the system homogeneity such as reduced viscosity, reduced mass transfer limitations, and the accessibility of the substrate to the active site of the enzyme.