Candida rugosa lipase‐catalyzed synthesis of sucrose‐6‐acetate in a 2‐butanol/buffer two‐phase system

Abstract

Sucrose‐6‐acetate, a short‐chain monoester, is an important intermediate for the preparation of sucralose. Regioselective transformations of mono‐ and oligosaccharides by enzymes have been performed in organic solvents. The present study was carried out with Candida rugosa lipase to synthesize sucrose‐6‐acetate by transesterification of sucrose and vinyl acetate in a two‐phase system consisting of a buffer solution and an organic solvent. The screening results revealed that 2‐butanol/Tris‐HCl was the optimal two‐phase system for biocatalysis, and other factors influencing the synthesis of sucrose‐6‐acetate were also studied. Three major factors (temperature, initial buffer pH, and molar ratio of substrates) were identified through Plackett–Burman design, and the response surface methodology was employed to optimize the reaction process. Under optimal conditions, the yield of sucrose‐6‐acetate reached up to 57.42%. The aqueous two‐phase system was successfully applied to the synthesis of sucrose‐6‐acetate with high yield, low toxicity, good resolution, low cost, and simple scale‐up.

Enzymatic Preparation of a Homologous Series of Long-Chain 6-O-Acylglucose Esters and Their Evaluation as Emulsifiers

“…The deficiencies associated with the current methods for manufacturing sucrose esters have attracted considerable attention, particularly from academic laboratories. Manifold efforts have been made to improve the current methods of manufacture by focusing on, for example, alternate acyl donors and reaction solvents, , new modes of promoting reaction (including through ultrasonic irradiation), and the use of biological catalysts (enzymes). − The main difficulties encountered in attempts to improve the yields of enzymatic couplings arise from the low activity of the biological catalysts in polar solvents such as DMSO and DMF that are required to dissolve the carbohydrates . To prevent enzyme deactivation it has been suggested that these highly polar solvents are doped with alcoholic ones such as 2-butanol or t -amyl alcohol , that serve as adjuvants.…”

“…12−16 The main difficulties encountered in attempts to improve the yields of enzymatic couplings arise from the low activity of the biological catalysts in polar solvents such as DMSO and DMF that are required to dissolve the carbohydrates. 13 To prevent enzyme deactivation it has been suggested that these highly polar solvents are doped with alcoholic ones such as 2-butanol 12 or t-amyl alcohol 1,14 that serve as adjuvants. Increasing the concentration of sucrose in the reaction medium to improve throughput while retaining the activity of the enzyme represents another challenge.…”

Comparative Study of the Emulsifying Properties of a Homologous Series of Long-Chain 6′-O-Acylmaltose Esters

“…While they are of particular utility in the food industry, there are fundamental challenges associated with their manufacture that arise from the presence of eight distinct hydroxyl groups within the carbohydrate core and the ensuing potential for formation of complex product mixtures that include various possible mono-, di-, tri-, and even higher-order esters. , Most of the sucrose esters on the market are currently manufactured by very traditional chemical techniques that involve reactions conducted under harsh conditions and subsequent, tedious purification . The enzymatic synthesis of sucrose esters has garnered considerable interest because of the potential for establishing environmentally benign processes that proceed with high selectivity and so simplifying downstream purification. − Nevertheless, the extensive studies − conducted thus far have revealed some major drawbacks associated with this approach, most notably the low activity of the enzymes in the polar organic solvents required to dissolve the carbohydrates, the relatively long reaction times involved (from 6 h to several days) as well as the low concentrations of the substrate that must be employed (and thus restricting throughput).…”

Phospholipase D encapsulated into metal-surfactant nanocapsules for enhancing biocatalysis in a two-phase system

“…4 For these reasons, the development of enzymatic catalysis in two-phase systems is of great interest for ne chemical and pharmaceutical processes. 5 However, unspecic binding of organic solvents to enzymes can promote unfolding or aggregation of the enzymes, which leads to irreversible inactivation. Organic solvents can also bind non-covalently to the substrate binding site or the substrate entrance channel of the enzyme, resulting in competitive inhibition.…”