Screening And Characterization Of H₂-Production Strain Enterbacter Sakazakii HP

As the economy develops, the energy source problem and the environmental issue are paid more and more attention. Developing new energy system has become basic. Many of the countries are concerning about the development of the new energy system. Hydrogen energy has been considered as one of the most ideal future energies as it is clean, pollution-free, high heat value and easily storage and transportation."Hydrogen economy"becomes an important part of program for economic development of many countries therefore.In this study, a high-efficient hydrogen producing strain has been isolated from the hot spring. It was identified as Enterbacter sakazakii by analysis of morphology, physiology and 16S rRNA gene sequence. Varies factors (e.g. pH, carbon sources, glucose concentration, temperature, O2 proportion and cell density) which influences the H2-production were investigated. After orthogonal experiment, the optimal conditions for hydrogen production were achieved as: initial pH value 8.0, using glucose as carbon sources, temperature 35℃, oxygen concentration 0%. In the batch fermentative hydrogen production, the maximal hydrogen production was obtained as 5.5mol/h?mg dw.The organic acid components of wastewater after dark-fermentative hydrogen production were analysed in this study. After 36 hours fermentation, the wastewater from Enterbacter sakazkii HP mainly contained acetic acid with a concentration of 2.22μg/mL and butyric acid with concentration of 3.33μg/mL. The wastewater from Klebsiella oxytoca HP1 mainly contained. The acetic acid's concentration in Klebsiella oxytoca HP1's wastewater was 0.66μg/mL and the butyric acid's concentration in it was 11.79μg/mL.The hydrogen can be produced by the photosynthetic bacteria (PSB) using acetic acid and butyric acid in the process of photofermentation. In this research, the pH value of the fermentative wastewater of Enterbacter sakazkii HP and Klebsiella oxytoca HP1 was adujsted to 7. The wastewater was then inoculated with Rhodopseudomona capsulate CN1. An elementary experiment about PSB which used anaerobic fermentative wastewater to produce hydrogen was done. As a result, the maximum value of photofermentative hydrogen production was found to be 0.12mmol H2/ml wastewater. This research proves that the method is useful for hydrogen transformation.