Kinetic Microbial Growth of Clostridium manihotivorum with Glucose under Anaerobic Digestion

The kinetics of glucose degradation by a pure culture of a mesophilic anaerobic bacteria, namely Clostridium manihotivorum, were studied. Various glucose concentrations ranging from 0.5 to 10 g/L were used as substrate in the batch fermentation to investigate microbial growth kinetics. The maximum specific growth rates (μ_max) and saturation constants (Ks) were determined. The experimental results showed that μ_max and Ks were 0.26 h^-1 and 0.45 g/L, respectively. Increasing substrate concentration resulted in a rising rate coefficient from 0.02 to 0.1 g/L.h. Additionally, at the optimum glucose concentration of 5 g/L, the highest cell concentration, substrate degradation rate, and maximum H₂ production yield were obtained at 8.28x10⁸ CFU/mL, 0.08 g/L.h, and 18.66 mL/g glucose, respectively. The major volatile fatty acids produced during anaerobic digestion were acetic acid (0.174 mM) and butyric acid (0.367 mM). This investigation enriches the understanding of microbial metabolism within distinct anaerobic digestion conditions.