Optimization of recovery of esterase from Serratia marcescens using combination of the solvent impregnated resin and aqueous two-phase extraction techniques

Extraction behaviors of aqueous PEG impregnated resin system in terms of impregnation stability and recovery via protein impregnated resin interactions on bovine serum albumin

Background

Current advances in biotechnology have been looked at as alternative approaches towards the limited product recovery due to time- and cost-consuming drawbacks on the conventional purification methods. This study aimed to purify bovine serum albumin (BSA) as an exemplary target product using an aqueous impregnated resin system (AIRS). This method implies the concept of hydrophobicity of polymer that impregnated into the resins and driven by electrostatic attractions and hydrophilicity of aqueous salt solution to extract the target product.

Methods

The extraction behaviors of impregnation in terms of stability and adsorption kinetics via protein-aqueous polymer impregnated resin were studied. Impregnation stability was determined by the leaching factor of polyethylene glycol (PEG). The major factors such as PEG molecular weights and concentration, pH of aqueous salt solution, extraction methods (sonication and agitation) and types of adsorbent material and concentration of aqueous salt phase influencing on partitioning of biomolecule were also investigated.

Results

For impregnation stability, the leaching factor for Amberlite XAD4 did not exceed 1%. The scanning electron microscopy (SEM) image analysis of Amberlite XAD4 attributes the structural changes with impregnation of resins. For adsorption kinetics, Freundlich adsorption isotherm with the highest R² value (0.95) gives an indication of favorable adsorption process. Performance of AIRS impregnated with 40% (w/w) of PEG 2000 was found better than aqueous-two phase system (ATPS) by yielding the highest recovery of BSA (53.72%). The outcomes of this study propound the scope for the application of AIRS in purification of biomolecules.

Recovery of a Bacteriocin-Like Inhibitory Substance from Lactobacillus bulgaricus FTDC 1211 Using Polyethylene-Glycol Impregnated Amberlite XAD-4 Resins System

Lactobacillus bulgaricus is a LAB strain which is capable of producing bacteriocin substances to inhibit Staphylococcus aureus. The aim of this study was to purify a bacteriocin-like inhibitory substance (BLIS) produced by L. bulgaricus FTDC 1211 using an aqueous impregnated resins system consisting of polyethylene-glycol (PEG) impregnated on Amberlite XAD4. Important parameters influencing on purification of BLIS, such as the molecular weight and concentration of PEG, the concentration and pH of sodium citrate and the concentration of sodium chloride, were optimized using a response surface methodology. Under optimum conditions of 11% (w/w) of PEG 4000 impregnated Amberlite XAD4 resins and 2% (w/w) of sodium citrate at pH 6, the maximum purification factor (3.26) and recovery yield (82.69% ± 0.06) were obtained. These results demonstrate that AIRS could be used as an alternate purification system in the primary recovery step.

Bioseparation of phycocyanin from Phormidium tergestinum using an aqueous two-phase system

This study aimed at purification of phycocyanin (PC) from Phormidium tergestinum using an aqueous two-phase system (ATPS) comprised of polyethylene glycol (PEG) and salts. The partitioning efficiency of PC in ATPS and the effect of phase composition, pH, crude loading, and neutral salts on purification factor and yield were investigated. Results showed that PC was selectively partitioned toward bottom phase of the system containing potassium phosphate. Under optimum conditions of 20% (w/w) PEG 4000, 10% (w/w) potassium phosphate, 20% (v/v) crude load at pH 7, with addition of 0.5% (w/w) NaCl, PC from P. tergestinum was partially purified up to 5.34-fold with a yield of 87.8%. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that the molecular weight of PC was ∼19 kDa. Results from this study demonstrated ATPS could be used as a potential approach for the purification of PC from P. tergestinum.

Extraction and Purification of Capsaicin from Capsicum Oleoresin Using a Combination of Tunable Aqueous Polymer-Phase Impregnated Resin (TAPPIR) Extraction and Chromatography Technology

Capsaicin, which mainly comes from pepper, exhibits anticancer, antioxidant, and anti-obesity properties. This work aims to construct a comprehensive technology for the extraction and purification of capsaicin from capsicum oleoresin. The tunable aqueous polymer phase impregnated HZ816 resins were selected in extraction step. In the extraction process, 3 g of impregnated HZ816 macroporous resin was employed per system. The results showed that a higher molecular weight of Polyethylene glycol (PEG) and 1-ethyl-3-methyl imidazolium acetate ([Emim] [OAc]) are more beneficial to the improvement of the yield of capsaicin. Screening experiment using fractional factorial designs indicated that the amount of sample loading, pH, and concentration of [Emim] [OAc] and PEG 6000 significantly affect the yield of capsaicin. Mathematical models of capsaicin yield in tunable aqueous polymer-phase impregnated resins were established and optimum condition was obtained using response surface methodology. The optimum impregnated phase was the polymer phase of an aqueous two-phase system which contained 18.5% (w/w) PEG6000, 15% (w/w) sodium citrate, and 10% (w/w) [Emim] [OAc] at pH 6.5. Under the optimal conditions, the yield of capsaicin reached 95.82% when the extraction system contains 0.25 g capsicum oleoresin. Ultimately, capsaicinoids extract was purified by reverse-phase resin (SKP-10-4300) chromatographic column. The capsaicin recovery and purity achieved 85% and 92%, respectively.