Abstract:The effects of glycin, glutamic acid, asparagin, pyruvic acid and a-oxoglutarate as additives on cell growth, maintenance, byproducts formation and glycerol production by C. glycerinogenes were investigated. The results showed that the addition of the above substances had little influence on cell growth during the whole fermentation process. However, it could hasten the glucose consumption rate, shorten the fermentation time, and enhance the glycerol yield on glucose. The glycerol productivities reached 1.66, 1.59, 1.61, 1.54 and 1.68 g/(L×h), respectively. As compared with the control, the glycerol productivities increased 25.18%, 19.21%, 20.77%, 15.92% and 26.32%, respectively. Further analysis indicated that the byproduct was mainly produced during the rapid growth phase, where the glucose consumption in cell growth, maintenance and glycerol production had little change. During the steady growth phase, the glucose consumption for cell growth, maintenance and byproducts formation decreased, thus resulting in the incremental carbon metabolic flux toward glycerol biosynthesis pathway.