Enzymatic synthesis of structured lipids from grape seed (Vitis vinifera L.) oil in associated packed bed reactors

Enzymatic production process of capric acid-rich structured lipids: Development of formulation as a new therapeutic approach

The present work reports an optimization of the synthesis of MLM-type (medium, long, medium) structured lipids (SL) through an acidolysis reaction of grape seed oil with capric acid catalyzed by Rhizopus oryzae lipase immobilized. At first, tests were carried out by preparing the biocatalysts using enzyme loadings (0.15 to 1 g of enzymatic powder) for each gram of support. Enzyme loading was used 0.3 g of enzymatic powder, and hydrolytic activity of 1860 ± 23.4 IU/g was reached. Optimized conditions determined by the Central Composite Rotatable Design (CCRD) revealed that the acidolysis reaction reached approximately 59 % incorporation degree (%ID) after 24 h, in addition to the fact that the biocatalyst could maintain the incorporation degree in five consecutive cycles. From this high incorporation degree, cell viability assays were performed with murine fibroblast cell lines and human cervical adenocarcinoma cell lines. Concerning the cytotoxicity assays, the concentration of MLM-SL to 1.75 and 2 % v/v were able to induce cell death in 56 % and 64 % of adenocarcinoma cells, respectively. Human cervical adenocarcinoma cells showed greater sensitivity to the induction of cell death when using emulsions with MLM-SL > 1.75 % v/v compared to emulsions with lower content indicating a potential for combating carcinogenic cells.

Solvent-Free Enzymatic Synthesis of Dietary Triacylglycerols from Cottonseed Oil in a Fluidized Bed Reactor

The synthesis of structured lipids with nutraceutical applications, such as medium-long-medium (MLM) triacylglycerols, via modification of oils and fats represents a challenge for the food industry. This study aimed to synthesize MLM-type dietary triacylglycerols by enzymatic acidolysis of cottonseed oil and capric acid (C10) catalyzed by Lipozyme RM IM (lipase from Rhizomucor miehei) in a fluidized bed reactor (FBR). After chemical characterization of the feedstock and hydrodynamic characterization of the reactor, a 2² central composite rotatable design was used to optimize capric acid incorporation. The independent variables were cycle number (20-70) and cottonseed oil/capric acid molar ratio (1:2-1:4). The temperature was set at 45 °C. The best conditions, namely a 1:4 oil/acid molar ratio and 80 cycles (17.34 h), provided a degree of incorporation of about 40 mol%, as shown by compositional analysis of the modified oil. Lipozyme RM IM showed good operational stability (k_d = 2.72 × 10^-4 h^-1, t_1/2 = 2545.78 h), confirming the good reuse capacity of the enzyme in the acidolysis of cottonseed oil with capric acid. It is concluded that an FBR configuration is a promising alternative for the enzymatic synthesis of MLM triacylglycerols.

Continuous Production of Dietetic Structured Lipids Using Crude Acidic Olive Pomace Oils

Crude olive pomace oil (OPO) is a by-product of olive oil extraction. In this study, low-calorie structured triacylglycerols (TAGs) were produced by acidolysis of crude OPO with medium-chain fatty acids (caprylic, C8:0; capric, C10:0) or interesterification with their ethyl ester forms (C8EE, C10EE). These new TAGs present long-chain fatty acids (L) at position sn-2 and medium-chain fatty acids (M) at positions sn-1,3 (MLM). Crude OPO exhibited a high acidity (12.05–28.75% free fatty acids), and high contents of chlorophylls and oxidation products. Reactions were carried out continuously in a packed-bed bioreactor for 70 h, using sn-1,3 regioselective commercial immobilized lipases (Thermomyces lanuginosus lipase, Lipozyme TL IM; and Rhizomucor miehei lipase, Lipozyme RM IM), in solvent-free media at 40 °C. Lipozyme RM IM presented a higher affinity for C10:0 and C10EE. Lipozyme TL IM preferred C10:0 over C8:0 but C8EE over C10EE. Both biocatalysts showed a high activity and operational stability and were not affected by OPO acidity. The New TAG yields ranged 30–60 and the specific productivity ranged 0.96–1.87 g NewTAG/h.g biocatalyst. Lipozyme RM IM cost is more than seven-fold the Lipozyme TL IM cost. Therefore, using Lipozyme TL IM and crude acidic OPO in a continuous bioreactor will contribute to process sustainability for structured lipid production by lowering the cost of the biocatalyst and avoiding oil refining.