Green and efficient production of octyl hydroxyphenylpropionate using an ultrasound-assisted packed-bed bioreactor

Abstract

A solvent-free system to produce octyl hydroxyphenylpropionate (OHPP) from p-hydroxyphenylpropionic acid (HPPA) and octanol using immobilized lipase (Novozym® 435) as a catalyst in an ultrasound-assisted packed-bed bioreactor was investigated. Response-surface methodology (RSM) and a three-level-three-factor Box-Behnken design were employed to evaluate the effects of reaction temperature (x₁), flow rate (x₂) and ultrasonic power (x₃) on the percentage of molar production of OHPP. The results indicate that the reaction temperature and flow rate were the most important variables in optimizing the production of OHPP. Based on a ridge max analysis, the optimum conditions for OHPP synthesis were predicted to consist of a reaction temperature of 65°C, a flow rate of 0.05 ml/min and an ultrasonic power of 1.74 W/cm² with a yield of 99.25%. A reaction was performed under these optimal conditions, and a yield of 99.33 ± 0.1% was obtained.

Continuous Production of 2-Phenylethyl Acetate in a Solvent-Free System Using a Packed-Bed Reactor with Novozym® 435

“…Solvent-free systems present advantages, such as offering greater safety, reduction in solvent extraction costs, increased reactant concentrations, consequently volume productivity, and being friendly to the environment [28]. To date, the solvent-free system has been developed successfully for the synthesis of many esters, such as octyl ferulate [29], octyl hydroxyphenylpropionate [30], caffeic acid phenethyl ester [31], ethyl valerate (green apple flavour) and hexyl acetate (pear flavour) [32]. So far, the use of solvent-free systems for enzymatic synthesis of 2-PEAc has not been reported.…”