Bioprocess Optimization
for Scalable O-Antigen Production in Vaccine Development
Eswar Reddy K. and Venkateswarulu T.C.
Res. J. Biotech.; Vol. 20(10); 319-327;
doi: https://doi.org/10.25303/2010rjbt3190327; (2025)
Abstract
O-polysaccharides are the main components in bacterial pathogenesis and vaccine
formulations, making their large-scale production essential for polysaccharide and
conjugate vaccine development. However, exact optimization of bacterial growth conditions,
fermentation techniques and hydrolysis parameters is necessary to achieve high-yield
and high-purity polysaccharide extraction. This study focuses on systematically
enhancing O-polysaccharide production from Salmonella enterica serovar Paratyphi
by refining key growth factor variables. The effects of temperature, pH, aeration,
nutrient supplementation and glucose feeding on bacterial growth and polysaccharide
biosynthesis were assessed using a thorough experimental design. Large-scale fed-batch
fermentation yielded superior results over batch fermentation, ensuring sustained
bacterial growth and continuous glucose availability for enhanced O-polysaccharide.
The acid hydrolysis process was optimized to prevent polysaccharide degradation
while maintaining structural integrity, with a 2-hour hydrolysis duration at pH
5.0 and 95°C identified as the optimal condition. Size-exclusion chromatography
(SEC) analysis confirmed that prolonged hydrolysis led to molecular fragmentation,
reinforcing the need for controlled extraction conditions. This study presents optimized
factors for bioprocess development combined with scalable and reproducible approach
for maximizing O-polysaccharide production, aligning with industrial demands for
efficient bioprocess development.
