Engineering Staphylococcal Protein A for high-throughput affinity purification of monoclonal antibodies.

Protein A chromatography is one of the most widely used purification steps in the manufacturing of the various classes of recombinant and non-recombinant antibodies. Due to the higher cost, lower binding capacity, and limited life cycle of Protein A ligand, this affinity-based purification step is often one of the most significant contributors to the cost of manufacturing of monoclonal antibody (mAb) products. In the last decade, there has been significant progress in improving the Protein A chromatography throughput by designing new engineered Staphylococcal Protein A (SPA) variants with higher dynamic binding capacity, considerable alkaline tolerance, and mild acidic elution pH. This review aims at summarizing the various protein engineering approaches used for improving the throughput of the Protein A-based affinity purification of various immunoglobulins. With biopharmaceutical producers operating under ever-increasing pressure towards reducing the cost of manufacturing, these advances in engineered protein A variants will help in processing larger cell culture volumes with high throughput and thereby significantly lower the cost of raw materials.

Synergistic effect of ultrasonication and co-immobilized enzymes on tomato peels for lycopene extraction.

In the present work, tomato peels were pre-treated using combination of ultrasound and enzyme co-immobilized amino-functionalized magnetic nanoparticles (AMNPs) for the efficient release of lycopene. To achieve maximum activity of enzymes in the co-immobilized form, optimization of several parameters were carried out. Moreover, the influence of ultrasound and enzyme co-immobilized magnetic nanoparticles on lycopene release was studied. Maximum lycopene release was obtained at 3% (w/w) enzyme co-immobilized AMNPs, pH 5.0, temperature of 50 °C, at 10 W ultrasound power and 20 min incubation time. After enzymatic pre-treatment, lycopene from the pre-treated mixture was extracted and separated using tri-solvent extraction method. Maximum recovery of lycopene using solvent extraction was obtained at 50 °C, 90 min of incubation time and agitation speed of 150 rpm. The presence of lycopene in the extract was confirmed by FT-IR, UV-vis spectroscopy and HPLC analysis. The co-immobilized bio-catalyst showed excellent reusability giving more than 50% lycopene yield even after 6th cycles of reuse.