| dc.description.abstract | Fructose palmitate (sugar ester) is a relatively new class of nonionic surfactants.
Their excellent biodegradability and low toxicity surfactant as well as effectiveness at
extreme temperature, pH and salinity show their increasing importance in numerous
areas of application. For a long time, large scale production of sugar ester was
dominated by conventional chemical processing. However, the conventional chemical
process leaves out bad impact to the human and environment. Compared to the
enzymatic synthesis, this process offers a safer and easier alternative. In the present
work, sugar ester production was developed by a novel and effective enzymatic method
which can reduce the advantages of conventional chemical process. Direct unprotected
sugar and non activated fatty acid were used as a starting material. Combination of
supersaturated sugar solution under anhydrous condition and stepwise addition of
molecular sieve as water absorbent agent during the reaction were found to be a suitable
method in increasing the reaction rate and fatty acid conversion. In this method,
influences of several parameters were investigated as a screening to the optimization
process. Results from screening were used to optimize and analyze fructose palmitate
(sugar ester) esterification using a response surface methodology (RSM) based on
central composite design (CCD). The 98.58 ± 0.52% of optimum fatty acid conversion
was determined by 11.92% (w/w of substrates) immobilized enzyme loading, 0.50M
fatty acid concentration, 10.0h reaction time and 53.67oC of reaction temperature. The
reusability of the immobilized enzyme was shown good conversion, were greater than
88% of fatty acid conversion after 10th reaction cycles without additional treatment of the immobilized enzyme. | en_US |
