The end-product concentration and productivity are critical issues in economic competition between biotechnological commercials and the chemical engineering industry. The prominent contradiction between high-titer products and the large-scale oxygen demand for aerobic biocatalysis leads to hyperviscosity, mass transport bottleneck in [dynamically changing](javascript:;) polyphase biosystems, and severe foaming problems. In this study, an intensification strategy for the whole-cell catalytic preparation of high-titer xylonic acid by Gluconobacter oxydans in a sealed-compressed oxygen supply bioreactor is propose. Multi-scale control factors are quantitatively studied to determine the biochemical parameter thresholds, and theoretically calculated the optimal production performance based on threshold effect. Finally, 650.8 g/L xylonic acid is obtained with a maximum productivity of 41.7 g/L/h with a catalytic performance of 95.8%, compared with the theoretical calculations. The intensification strategy for the oxygen transfer threshold effect overcome the stubborn obstacles of obligate aerobic catalysis, while providing a sustainable value-added pathway for fermentative lignocellulose.

The end-product concentration and productivity are critical issues in economic competition between biotechnological commercials and the chemical engineering industry. The prominent contradiction between high-titer products and the large-scale oxygen demand for aerobic biocatalysis leads to hyperviscosity, mass transport bottleneck in [dynamically changing](javascript:;) polyphase biosystems, and severe foaming problems. In this study, an intensification strategy for the whole-cell catalytic preparation of high-titer xylonic acid by Gluconobacter oxydans in a sealed-compressed oxygen supply bioreactor is propose. Multi-scale control factors are quantitatively studied to determine the biochemical parameter thresholds, and theoretically calculated the optimal production performance based on threshold effect. Finally, 650.8 g/L xylonic acid is obtained with a maximum productivity of 41.7 g/L/h with a catalytic performance of 95.8%, compared with the theoretical calculations. The intensification strategy for the oxygen transfer threshold effect overcome the stubborn obstacles of obligate aerobic catalysis, while providing a sustainable value-added pathway for fermentative lignocellulose.