Related Experiment Video
Updated: Feb 22, 2026

Light-Controlled Fermentations for Microbial Chemical and Protein Production
Published on: March 22, 2022
Potential use and the energy conversion efficiency analysis of fermentation effluents from photo and dark
Zhiping Zhang1, Yameng Li1, Huan Zhang1
1Collaborative Innovation Center of Biomass Energy, Henan Province, Henan Agricultural University, Zhengzhou 450002, PR China.
Abstract:
Effluent of bio-hydrogen production system also can be adopted to produce methane for further fermentation, cogeneration of hydrogen and methane will significantly improve the energy conversion efficiency. Platanus Orientalis leaves were taken as the raw material for photo- and dark-fermentation bio-hydrogen production. The resulting concentrations of acetic, butyric, and propionic acids and ethanol in the photo- and dark-fermentation effluents were 2966mg/L and 624mg/L, 422mg/L and 1624mg/L, 1365mg/L and 558mg/L, and 866mg/L and 1352mg/L, respectively. Subsequently, we calculated the energy conversion efficiency according to the organic contents of the effluents and their energy output when used as raw material for methane production. The overall energy conversion efficiencies increased by 15.17% and 22.28%, respectively, when using the effluents of photo and dark fermentation. This two-step bio-hydrogen and methane production system can significantly improve the energy conversion efficiency of anaerobic biological treatment plants.
Related Concept Videos
Fermentation
Fermentation is a type of metabolic process that occurs in the absence of oxygen, where organic molecules such as glucose are broken down to produce energy. During this process, the...
Microbial Fermentation
Fates of Pyruvate
In aerobic organisms, pyruvate is metabolized via the citric acid cycle to produce reduced coenzymes NADH and FADH2. These coenzymes are then oxidized in the electron transport chain to produce ATP and, in the process, regenerate the NAD+ and FAD. As seen in some cell types and organisms, fermentation...
Environmental Applications of Microorganisms

