Extraction and Process Conditions Optimization of Ficin by Ionic Liquid Aqueous Two-phase System

In order to research the application of [C4mim] Br-K2HPO4 ionic liquid aqueous two-phase system to extract ficin, the influence of reagents to the activity of ficin have been investigated. This study aimed to investigate the effects of species and concentration of the ionic liquid, the dosage of ficin, pH value and temperature on the partitioning behavior of ficin, respectively. Response surface methodology was used to predict the extraction conditions of ficin. Results of the trial indicated that heating up to a certain extent was advantageous, however, high temperature was detrimental to the ionic liquid aqueous two-phase system on extraction of ficin. The most two important factors were concentration of [C4mim] Br and concentration of K2HPO4 on partitioning behavior of ficin. Followed by pH value and dosage of ficin. The optimized extraction conditions were as follows: the [C4mim] Br content was 0.25 g·mL-1; the K2HPO4 content was 0.39 g·mL-1; pH 9.18; the dosage of ficin was 12.39 g·mL-1; the reaction temperature at 40 . The purification factor achieved °C 16.7 and the activity recovery of enzyme achieved 108.12% under this optimum conditions. The technology will vigorously promote the development of ficin industrialization and it has stimulative effect on the development of ionic liquids aqueous two-phase extraction technology.