Immobilization of Rhizomucor miehei lipase on magnetic multiwalled carbon nanotubes towards the synthesis of structured lipids rich in sn-2 palmitic acid and sn-1,3 oleic acid (OPO) for infant formula use.

Nowadays, breast milk is considered as the ideal food for infants owing to the most common oleic acid-palmitic acid-oleic acid (OA-PA-OA) fatty acid distribution of the human milk fat (HMF). This study reports the synthesis of 1,3-dioleoyl-2-palmotoylglycerol (OPO)-rich human milk fat substitutes in a two-step enzymatic acidolysis reaction with Rhizomucor miehei lipase (RML) immobilized on magnetic multi-walled carbon nanotubes(mMWCNTs). The immobilized RML (RML-mMWCNTs) showed better thermal and pH stability, convenient recovery and reusability than the free soluble form. Under optimized reaction conditions (1:8 tripalmitin (PPP)/OA, 10%wt. enzyme, 50 °C, 5 h), PA content at the sn-2 position and OA incorporation at the sn-1,3 positions reached 93.46% and 59.54%, respectively. Comparison tests have also showed that RML-mMWCNTs has better catalytic activity and reusability than the commercial lipase Lipozyme RM IM. The results suggest that RML-mMWCNTs is a promising biocatalyst for the synthesis of OPO-rich TAGs with potential use in infant formulas.

Co-Immobilization of Rhizopus oryzae and Candida rugosa Lipases onto mMWCNTs@4-arm-PEG-NH2-A Novel Magnetic Nanotube-Polyethylene Glycol Amine Composite-And Its Applications for Biodiesel Production.

This article describes the successful synthesis of a novel nanocomposite of superparamagnetic multi-walled nanotubes with a four-arm polyethylene glycol amine polymer (mMWCNTs@4-arm-PEG-NH2). This composite was then employed as a support for the covalent co-immobilization of Rhizopus oryzae and Candida rugosa lipases under appropriate conditions. The co-immobilized lipases (CIL-mMWCNTs@4-arm-PEG-NH2) exhibited maximum specific activity of 99.626U/mg protein, which was 34.5-fold superior to that of free ROL, and its thermal stability was greatly improved. Most significantly, CIL-mMWCNTs@4-arm-PEG-NH2 was used to prepare biodiesel from waste cooking oil under ultrasound conditions, and within 120 min, the biodiesel conversion rate reached 97.64%. This was due to the synergy effect between ROL and CRL and the ultrasound-assisted enzymatic process, resulting in an increased biodiesel yield in a short reaction time. Moreover, after ten reuse cycles, the co-immobilized lipases still retained a biodiesel yield of over 78.55%, exhibiting excellent operational stability that is attractive for practical applications. Consequently, the combined use of a novel designed carrier, the co-immobilized lipases with synergy effect, and the ultrasound-assisted enzymatic reaction exhibited potential prospects for future applications in biodiesel production and various industrial applications.

1,3-Dioleoyl-2-palmitoyl glycerol (OPO)-Enzymatic synthesis and use as an important supplement in infant formulas.

1,3-dioleolyl-2-palmitate (OPO) is an important component of the human milk fat. Its unique fatty acid composition and distribution play an important role in proper infant growth and development. Owing to this, it has been attracting researchers and manufacturers to synthesize and commercialize OPO as an important human milk fat substitute added to infant formulas. In this review, the role of OPO in human milk, the benefits of OPO (sn-2 palmitate)-supplemented infant formulas over the conventional infant formulas on infant growth, and lipase-catalyzed synthesis of OPO are discussed. Over the last 20 years of research on the benefits of OPO (sn2 palmitate)-supplemented infant formulas are summarized. Similarly, studies carried out on lipase catalyzed production of OPO for the last 21 years (1999-2019) are also done focusing on the raw materials, sn1,3-regiospecific lipases, immobilization materials, and solvents used in the laboratory-scale experiments. In addition, OPO-based products currently in the market and future research trends are briefly covered in this review. PRACTICAL APPLICATIONS: This work focuses on lipase-catalyzed synthesis of 1,3-dioleoyl-2-palmitoylglycerol (the most abundant triacyl glycerol in human milk fat) and its benefits to infants when it is added in infant formulas. Over the last 20 years of published research from the literature are summarized and future research trends for efficient OPO synthesis are also covered. This will provide current and future researchers on the field with the necessary background information on OPO synthesis and design their research plans accordingly for cost-effective production of OPO and OPO-supplemented infant formulas.