Vitamin B12 and propionic acid that were simultaneous produced by Propionibacterium freudenreichii are both favorable chemicals widely used in food preservatives, medicine, and nutrition. While the carbon source and propionic acid accumulation reflected fermentation efficiency. In this study, using corn stalk as a carbon source and fed-batch fermentation process in an expanded bed adsorption bioreactor was studied for efficient and economic biosynthesis of acid vitamin B12 and propionic. With liquid hot water pretreated corn stalk hydrolysates as carbon source, 28.65 mg L⁻¹ of vitamin B12 and 17.05 g L⁻¹ of propionic acid were attained at 168 h in batch fermentation. In order to optimize the fermentation outcomes, fed-batch fermentation was performed with hydrolyzed corn stalk in expanded bed adsorption bioreactor (EBAB), giving 47.6 mg L⁻¹ vitamin B12 and 91.4 g L⁻¹ of propionic acid at 258 h, which correspond to product yields of 0.37 mg g⁻¹ and 0.75 g g⁻¹, respectively. The present study provided a promising strategy for economically sustainable production of vitamin B12 and propionic acid by P. freudenreichii fermentation using biomass cornstalk as carbon source and expanded bed adsorption bioreactor.

费氏丙酸杆菌同时生产的维生素B12和丙酸都是在食品防腐剂，药物和营养中广泛使用的有利化学物质。碳源和丙酸的积累反映了发酵效率。在这项研究中，以玉米秸秆为碳源，并在扩展床吸附生物反应器中分批补料发酵过程，研究了酸性维生素B12和丙酸的高效经济合成。以液态热水预处理的玉米秸秆水解产物为碳源，维生素B12为28.65 mg L ^-1，维生素B12为17.05 g L ^-1在分批发酵中，在168 h达到100％的丙酸。为了优化发酵结果，在扩展床吸附生物反应器（EBAB）中用水解的玉米秸秆进行分批补料发酵，在258 h时得到47.6 mg L ^-1维生素B12和91.4 g L ^-1丙酸，对应得到的产物产率分别为0.37mg g ^-1和0.75g g ^-1。本研究为利用生物量玉米秸秆作为碳源和膨胀床吸附生物反应器的弗氏疟原虫发酵经济地可持续生产维生素B12和丙酸提供了有希望的策略。