Preparation of Docosahexaenoic Acid‐Rich Diacylglycerol‐Rich Oil by Lipase‐Catalyzed Glycerolysis of Microbial Oil from Schizochytrium sp. in a Solvent‐Free System

Abstract

Docosahexaenoic acid (DHA)‐rich diacylglycerol (DAG)‐rich oil was prepared by lipase‐catalyzed glycerolysis of microbial oil from Schizochytrium sp. in a solvent‐free system. The reaction parameters including lipase type, substrate molar ratio, temperature, lipase concentration, and reaction time were screened. The selected conditions were determined as follows: Novozym® 435 (Novozymes A/S, Bagsvaerd, Denmark) as biocatalyst at 8 wt%, substrate ratio (DHA‐rich microbial TAG/glycerol) of 1:1 mol/mol, temperature of 50 °C, and reaction time of 12 hours. Under these conditions, the triacylglycerol (TAG), DAG, and monoacylglycerol (MAG) contents in the product were 36.4%, 48.2%, and 15.4%, respectively. The lipase was reused successively for 18 cycles without significant loss of activity under the conditions given above. Fatty acid composition analysis of the final product showed that the contents of DHA in TAG, DAG, and MAG were 53.9%, 44.9%, and 34.8%, respectively. DHA‐rich DAG has the potential to be used as an ingredient in infant formula to increase the bioavailability of DHA.

Enzymatic Synthesis of Diacylglycerol-Enriched Oil by Two-Step Vacuum-Mediated Conversion of Fatty Acid Ethyl Ester and Fatty Acid From Soy Sauce By-Product Oil as Lipid-Lowering Functional Oil

“…Our findings demonstrated that DAG-enriched oil was produced by combined glycerolysis of EE and esterification of FFA with glycerol, using a low-cost refined SSBO containing a high content of EE and FFA as raw material. A high content of DAG (around 66%) was obtained in this study, especially a higher content of 1,3-DAG (62.62%), which was higher than that of esterification of high-acid oil and glycerolysis of TAG oil in the previous studies ( 19 , 37 , 39 ). These results were attributable to the higher conversion of EE and FFA to DAG through a two-step vacuum-mediated catalysis by 1,3-specific lipase ANL-MARE.…”

“…Glycerolysis is the most economical and industrial promising method for the production of DAG ( 17 ). The high content of DAG (about 60-65%) was synthesized by enzymatic glycerolysis using commercial lipases ( 18 ), and the docosahexaenoic acid-rich DAG-rich oil was also produced by lipase-catalyzed glycerolysis of microbial oil in a solvent-free system ( 19 ). Additionally, Awadallak et al provided a new approach to producing a high content of DAG (55.6%) from linseed oil by combining enzymatic glycerolysis and esterification ( 20 ).…”

One Pot Use of Combilipases for Full Modification of Oils and Fats: Multifunctional and Heterogeneous Substrates

“…They belong to the class of hydrolases (EC 3.1.1.1) and their natural function is the hydrolysis of triglycerides to fatty acids and glycerol. Nevertheless, under non-aqueous conditions, lipases are able to catalyze a broad range of reactions such as esterification, transesterification, and interesterification or acidolysis [165][166][167][168][169][170][171][172][173][174][175][176][177]. Moreover, besides this broad range of reactions, lipases are able to recognize a vast diversity of substrates, being able to catalyze even promiscuous reactions [178,179].…”

Lipase-catalyzed solvent-free synthesis of monoglycerides from biodiesel-derived crude glycerol: Optimized using response surface methodology

“…Microbial oils have also been used as synthetic monoglycerides. Zou et al [ 15 ] examined lipase type, substrate molar ratio, temperature, enzyme addition, and reaction time under solvent-free conditions. The results showed that the monoglyceride content was 15.4 % after 12 h of reaction at 50 °C under 8 wt% de Novozym 435 with a glycerol/oil ratio of 1:1.…”