Rosin, an abundant raw material from pine trees, was used as a starting material directly for the synthesis of rosin acid starch. The esterification reaction was catalyzed by lipase (Novozym 435) under mild conditions. Based on single factor experimentation, the optimal esterification conditions were obtained as follows: rosin acid/anhydrous glucose unit in the molar ratio 2:1, reaction time 4 ...

The effect of initial water activity of MTBE (methyl tert-butyl ether) medium on CALB (Candida antarctica lipase B) catalyzed esterification reaction is investigated using experimental methods and classical molecular dynamics (MD) simulations. The experimental kinetic studies show that the initial reaction rate of CALB-catalyzed esterification reaction between butyric acid and ethanol decreases...

Esterification and click-chemistry were evaluated as surface modification treatments for TEMPO-oxidized nanocelluloses (TONC) using Polycaprolactone-diol (PCL) as modifying compound in order to improve the dispersion of nanofibers in organic media. These two grafting strategies were analyzed and compared. The first consists of grafting directly the PCL onto TONC, and was carried out by esterifi...

Esterification reactions of some polyols and diols were investigated in the presence of SnO2 and nano-SnO2 and the results were compared with the catalyst-free conditions. High conversions were obtained for most of the reactions in the presence of SnO2 and nano-SnO2 which shows the high catalytic activity of SnO2 and nano-SnO2</sub...

The process of biodiesel production by the hydroesterification route that is proposed here involves a first step consisting of triacylglyceride hydrolysis catalyzed by lipase from Thermomyces lanuginosus (TL 100L) to generate free fatty acids (FFAs). This step is followed by esterification of the FFAs with alcohol, catalyzed by niobic acid in pellets or without a catalyst. The best result for t...

Butyl ferulate was synthesized using a silica-immobilized commercial lipase (Steapsin) in dimethylsulfoxide (DMSO). Lipase-immobilized by surface adsorption onto silica pretreated with 1% glutaraldehyde showed 89% binding of protein. The esterification of butanol (100 mM) and ferulic acid (50 mM) by silica-bound biocatalyst was carried out at 45 ̊C for 6 h under shaking (120 rpm). The optimizati...

We report a simple, convenient, and reproducible method, involving the use of radiolabeled cholesterol dispersed in Tween 20 as a tracer and endogenous lipoproteins as a substrate, for measuring the rate of serum cholesterol esterification in vitro. The reaction of lecithin acyltransferase (EC 2.3.1.43) was enhanced by the presence of Tween 20, which probably accelerates the exchange between ra...

More environmentally benign alternatives to current chemical processes, especially large-scale, fundamental reactions such as ester condensations, are highly desirable for many reactions. Bulky diarylammonium pentafluorobenzenesulfonates and tosylates serve as extremely active dehydration catalysts for the ester condensation reaction of carboxylic acids with equimolar amounts of sterically dema...

The esterification of lauric acid with lauryl alcohol was studied using lipase from Porcine pancreas, with particular emphasis on the effect of the pertinent variables and kinetic aspects of the reaction. The reaction was studied in eight different solvents having hydrophobicity (the logarithm of octanol-water partition coefficient, log P) values ranging from 0.6 to 3.5 with constant water cont...

Short chain citronellyl esters were synthesized by a new microbial lipase from Rhizopus sp strain isolated and lipase produced at UNICAMP, Brazil. Direct esterification and transesterification reactions have been performed to produce citronellyl acetate and butyrate in a free-solvent system and with n-hexane in reaction medium. Reaction mixture for direct esterification and transesterification ...