Liquid–liquid extraction of proteases from fermented broth by PEG/citrate aqueous two-phase system

Optimization of Aqueous Two-Phase Systems for the Recovery of Soluble Proteins from Tannery Wastewater Using Response Surface Methodology

“…Therefore, because of "volume exclusion effect" all the biomolecules tend to partition towards the bottom phase and thus percentage recovery in the bottom phase increases [27].…”

Liquid–liquid extraction of biomolecules: an overview and update of the main techniques

“…On the other hand, purification factor PF and selectivity S were lower than those ensured by more selective purification methods. 49 As a natural continuation of the work, the reduction of the toxicity of C. perfringens in fermentation broths (used in vaccine preparation) was developed using PEG/citrate aqueous two phase systems for removal of toxin-activating proteases. In order to establish the conditions under which the phase separation occurs, binodal curves, formed by PEG and sodium citrate, were investigated at different values of pH and PEG molar mass.…”

“…After statistical experimental planning, it was found that simultaneous increase in PEG molar mass and decrease in citrate concentration remarkably improved the removal factor, whereas the protease removal yield showed an opposite trend, 50 confirming previous results reported by Porto and co-workers. 49 Finally, bromelain (enzymatic complex obtained from pineapple, Ananas comosus, fruits and stem) was investigated by thermoseparation using by poly(ethylene oxide) (PEO)-poly(propylene oxide) (PPO)-poly (ethylene oxide) (PEO)block copolymers aqueous solutions. Triblock copolymers with different EO percentages and different molar masses were evaluated.…”

Prediction of liquid-liquid equilibria for polyethylene glycol based aqueous two-phase system by ASOG and UNIFAC method

“…These salts, however, led to high concentration of sulphate and phosphate salts in the effluent streams, causing environmental problems. Recently, Porto et al (2008) and Tubio et al (2007) Murugesan and Perumalsamy (2005) ZafaraniMoattar et al (2004ZafaraniMoattar et al ( , 2008 have used citrate, as a substitute for phosphate and sulphate salts to form aqueous two phase system with polyethylene glycol (PEG). Since citrates are biodegradable and nontoxic, PEG + citrate salts form environmentally safe aqueous two-phase systems, more suitable for the extraction of biological materials.…”

“…The PEG-Citrate salt based aqueous two phase system was used for the purification of Bovine Serum albumin (BSA) and reported in a previous article (Perumalsamy and Murugesan, 2007). Porto et al (2008) used PEG/Citrate systems to remove proteases from a Clostridium perfringens fermentation broth. Tubio et al (2007) studied the effect of different factors such as polyethyleneglycol molecular weight, pH, tie line length, temperature and the presence of an inorganic salt on the protein partition coefficient.…”