Optimization and semi-continuous fermentation of gluco-oligosaccharide production with Weissella cibaria YRK005

In this study, we optimized gluco-oligosaccharide production using Weissella cibaria YRK005 through a semi-continuous fermentation. The Plackett–Burman design identified sucrose and maltose concentrations and fermentation temperature as key factors. Optimization using response surface methodology with a central composite design identified optimal conditions as 14.7% w/v sucrose, 13.5% w/v maltose, and 30 °C, predicting a relative peak area (RPA) of 115.6. Comparative analysis of the anaerobic and aerobic batch fermentation showed higher productivity under the aerobic conditions (25.5 RPA/h) than under the anaerobic conditions (23.7 RPA/h). The aerobic semi-continuous fermentation, with media replenishment every 7 h, achieved 39.2 RPA/h in one-cycle fermentation, exceeding the 27.2 RPA/h in two-cycle fermentation. These results highlight the importance of fermentation conditions in enhancing gluco-oligosaccharide production and suggests that the aerobic semi-continuous fermentation is a promising strategy for industrial applications to increase efficiency and reduce costs.