Esterification of polyglycerol with polycondensed ricinoleic acid catalysed by immobilised Rhizopus oryzae lipase

Abstract

The enzymatic method for synthesising polyglycerol polyricinoleate (PGPR), a food additive named E-476, was successfully carried out in the presence of immobilised Rhizopus oryzae lipase in a solvent-free medium. The great advantage of using the commercial preparation of R. oryzae lipase is that it is ten times cheaper than the commercial preparation of R. arrhizus lipase, the biocatalyst used in previous studies. The reaction, which is really a reversal of hydrolysis, takes place in the presence of a very limited amount of aqueous phase. Immobilisation of the lipase by physical adsorption onto an anion exchange resin provided good results in terms of activity, enzyme stability and reuse of the immobilised derivative. It has been established that the adsorption of R. oryzae lipase on Lewatit MonoPlus MP 64 follows a pseudo-second order kinetics, which means that immobilisation is a process of chemisorption, while the equilibrium adsorption follows a Langmuir isotherm. The use of this immobilised derivative as catalyst for obtaining PGPR under a controlled atmosphere in a vacuum reactor, with a dry nitrogen flow intake, allowed the synthesis of a product with an acid value lower than 6 mg KOH/g, which complies with the value established by the European Commission Directive. This product also fulfils the European specifications regarding the hydroxyl value and refractive index given for this food additive, one of whose benefits, as proved in our experiments, is that it causes a drastic decrease in the viscosity (by 50 %) and yield stress (by 82 %) of chocolate, comparable to the impact of customary synthesised PGPR.

Optimization of oligoglycerol fatty acid esters preparation catalyzed by Lipozyme 435

“…The enzymatic method is preferred as enzymes are generally more specific, react under mild conditions, and produce less side products (Panpipat et al, 2012, Blasi et al, 2007. The lipase-catalyzed synthesis of PGEs through the esterification or transesterification of polyglycerol with fatty acids or methyl esters has been studied thoroughly (Ortega et al, 2014, Ortega et al, 2013, Xiao et al, 2012, Charlemagne and Legoy, 1995. All of these processes are solvent-free systems.…”

Study of different reaction schemes for the enzymatic synthesis of polyglycerol polyricinoleate

“…The enzymatic synthesis of polyglycerol polyricinoleate (PGPR) from ricinoleic acid (RA) and polyglycerol (PG) has been described by the authors in previous articles . The reaction scheme proposed for the biocatalytic synthesis is similar to the traditional chemical procedure and takes place in two steps: first, RA condenses to yield polyricinoleic acid (PR) catalysed by Candida rugosa lipase (CRL) and then the condensed product is esterified by PG catalysed by Rhizopus oryzae lipase (ROL).…”

“…The first procedure, the ‘normal‐reaction scheme’, has been described elsewhere . The second option consisted of reversing the order of the reaction steps.…”

“…3.1.1.3), which act in mild reaction conditions and produce a final product more suitable for use as a food additive. This enzymatic procedure consisted of two steps: first, the condensation of ricinoleic acid biocatalysed by Candida rugosa lipase and then the esterification of polyricinoleic acid with polyglycerol to obtain polyglycerol polyricinoleate (PGPR), using either Rhizopus arrhizus lipase or Rhizopus oryzae lipase . All of these reactions are solvent‐free systems that can be regarded as a green alternative to the use of organic solvents, which may leave undesirable residues in products.…”

Production and Emulsifying Effect of Polyglycerol and Fatty Acid Esters with Varying Degrees of Esterification

“…Analysis of fatty acid esters with polyatomic alcohol polymer analogues, in particular polyglycerol [1], including those obtained using immobilized enzymes [2], has set a new trends in the search for effective emulsifiers. Esters of polyglycerol are widely used in the food industry as oxygenators, structural modifiers, conditioners for dough, antifoam agents, and antisprays, and in non-food industries including pharmaceuticals (pastes, creams, suppositories), cosmetics (creams, lotions, hair-dyes) and textiles [3][4][5][6].…”