Sustainable Setups for the Biocatalytic Production and Scale-Up of Panthenyl Monoacyl Esters under Solvent-Free Conditions

Abstract

A sustainable scaling-up process for the biocatalytic production of new bioactive provitamin-B 5 monoacyl esters has been demonstrated. A solvent-free reaction protocol, based on the formation of eutectic mixtures between neat substrates, renders highly efficient direct esterification of free fatty acids (i.e., from C 6 to C 18 alkyl-chain length) with panthenol catalyzed by lipase. The scale-up from 0.5 to 500 g was evaluated by means of using several reaction systems (i.e., ultrasound assistance, orbital shaking, rotary evaporator, and mechanical stirring coupled to vacuum). For all reactor systems, the yield in panthenyl monoacyl esters was improved by increasing the length of the alkyl chain of the fatty acid (i.e., from 63% yield for panthenyl butyrate to 83% yield for panthenyl myristate). The best results (87−95% product yield, for all cases) were obtained upon a scale-up (50−500 g size) and when a vacuum system was coupled to the biocatalytic reaction unit. Under the optimized conditions, a 5-fold reduction of the amount of biocatalysts with respect to reactors without vacuum was achieved. The recovery and reuse of the immobilized enzyme for five operation cycles were also demonstrated. Finally, different metrics have been applied to assess the greenness of the solvent-free biocatalytic synthesis of panthenyl monoesters here reported.

Esters in the Food and Cosmetic Industries: An Overview of the Reactors Used in Their Biocatalytic Synthesis

“…To incorporate a greater number of studies, the search parameters were adjusted by removing the term “cosmetic”, resulting in 62 papers, of which 43 studies met the established criteria (tank reactors with a volume superior than 50 mL and cosmetic applications). Table 5 [ 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 , 83 , 84 , 85 , 86 , 87 , 88 , 89 , 90 , 91 , 92 , 93 , 94 , 95 , 96 , 97 , 98 , 99 , 100 , 101 , 102 ] compiles these papers. The esters synthesized fall into these categories: emollient esters [ 60 , 61 , 62 , 65 , 69 , 70 , 71 , ...…”

“…Table 5 [ 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 , 83 , 84 , 85 , 86 , 87 , 88 , 89 , 90 , 91 , 92 , 93 , 94 , 95 , 96 , 97 , 98 , 99 , 100 , 101 , 102 ] compiles these papers. The esters synthesized fall into these categories: emollient esters [ 60 , 61 , 62 , 65 , 69 , 70 , 71 , 73 , 74 , 79 , 80 ,…”

“…This guarantees a constant supply of enzymes. According to Table 5 , among 43 papers reviewed, 36 report the use of commercial lipases from different companies: Novozymes [ 60 , 61 , 62 , 63 , 64 , 65 , 66 , 68 , 70 , 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 82 , 88 , 90 , 91 , 92 , 93 , 96 , 97 , 98 , 99 , 101 ], Fermenta Biotech Ltd. (Thane, India) [ 71 , 81 , 83 , 84 , 86 , 89 , 95 ], and Purolite (King of Prussia, PA, USA) [ 80 ]. In five articles, researchers describe the use of an in-lab immobilized lipase [ 61 , 69 , 85 , 94 , 100 , 102 ], and only two studies involve microbial cells with lipase activity [ 67 , 87 ].…”

“…These methods involve the use of molecular sieves [ 64 , 67 , 71 , 75 , 81 ], vacuum operation with dry N 2 bubbling [ 66 , 69 , 70 , 72 , 73 , 80 , 85 , 91 , 93 , 97 , 100 ], and atmospheric evaporation [ 69 , 70 , 92 , 96 , 98 , 99 ]. Regarding the use of organic solvents as a reaction medium, solvent-free systems are becoming more prevalent [ 61 , 62 , 66 , 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 , 79 , 80 , 81 , 82 , 83 , 84 , 85 , 86 , 89 , 91 , 92 , 93 , 95 , 96 , 97 , 98 , 99 , 100 , 101 , 102 ]. This is probably ...…”

Green Production of a High-Value Branched-Chain Diester: Optimization Based on Operating Conditions and Economic and Sustainability Criteria

“…These productivities are similar to those declared in other studies of ester production in solventfree systems. Thus, some authors reported productivities of 0.033 kg/L h in the production of panthenyl triacetate [42], 0.15 kg/L h for neopentyl glycol dicaprilate/dicaprate [43], and a value of 0.217 kg/L h panthenyl monolaurate [44].…”