Isolation and purification of protease from human placenta by foam fractionation

Abstract

The effect of operating parameters like pH, protein concentration, column geometry, and gas flow rate on the separation efficiency of proteolytic enzymes from crude human placental homogenate has been studied in a batch foam column. Purification has been found to be optimum at pH 8.0, close to the isoelectric pH, at which the surface adsorption of the protein on the foam bubbles is maximum. Both purification and recovery varied significantly with total protein concentration. Stable bubble formation was hindered at lower protein concentrations, while extraneous proteins rather than the protease were preferentially adsorbed at higher protein concentrations, decreasing the purification efficiency. Column diameter and column height should be optimized for any specific feed protein concentration and gas flow rate. However, the enrichment ratio was found to decrease with the increase in flow rate. The results indicate that foam fractionation is an effective separation process for recovering valuable biochemicals from biological materials.

Adsorption of Water-Soluble Proteins onto Bubbles in Continuous Foam Separation

“…S b , W f0 and C f0 have already been estimated, therefore, we can now plot Eq. [7] for both OA and HB as shown in Fig. 7.…”

“…[7] is a modified form of the Langmuir adsorption isotherm for the present system. The slope and the intercept of the straight line give the values of K and γ, respectively.…”

“…Judging from the fact that the data for both OA and HB are in good accordance with Eq. [7], the adsorption behavior of OA and HB on the bubble surface in a continuous foam separation system should be expressed by Langmuir's isotherm. From the intercept and the slope of each line, the equilibrium constant, K, and the saturated surface density, γ, were obtained for OA and HB as listed in Table 1.…”

“…Recently, it appears that the separation of proteins by this method has been studied based on interest in applicability to food and biochemical industries (3)(4)(5)(6)(7). For the optimal design and operation of industrial processes, it is necessary to determine the adsorption and enriching mechanism of protein onto bubble surface in this technique.…”

Variation of saturated surface density of ovalbumin on bubble surface in continuous foam separation

“…This technique has been studied in many fields, such as chemical/biochemical engineering [1][2][3][4][5][6], analytical chemistry [7,8], wastewater treatment [9][10][11] and so on.…”