Isolation Of Hydrogen-producing Bacteria And Microbial Community Structure Of Bio-hydrogen Production From Food Origin Waste

The technology of fermentative bio-hydrogen production using food origin waste can bear high organic loading. There are other advantages: high hydrogen yield, producing hydrogen without light, wide range of carbon sources and simple process. It is very important to relief energy shortage. Therefore, fermentative bio-hydrogen production will be the main method to deal with food origin waste.Isolation of hydrogen-producing bacteria, optimization of bio-hydrogen producing system and difference analysis of microbial community structure was studied. Conclusions are as follows:(1) 48 strains bacteria were isolated by five media. Ten(HBZ103, HBZ104, HBZ108, HBZ110, HBZ203, HBZ204, HBZ305, HBZ502, HBZ504 and HBZ514) of them were hydrogen-producing bacteria. They were lactobacillus sp. by 16S rDNA identification.(2) Growth properties of strain HBZ108 and HBZ203 were studied. The results showed that the two strain were strictly anaerobic, gram-positive. The optimum pH of strain HBZ108 and HBZ203 were 7.0 and 6.0, repectively. The optimum temperature of the two strain were 35℃. The two strain use various carbon sources. The highest OD value of strain HBZ108 was obtained from mannitol. And the highest OD value of strain HBZ203 was obtained from glucose.(3) Alkaline agent XYF and aged refuse were demonstated to enhance hydrogen production using food origin waste. Difference analysis of microbial community structure showed that microbial community structure and population of anaerobic sludge were successional. At different stage, amount and positon of lanes of group A (control group)was similar to group B(experimental group with aged refuse), and those of group C(experimental group with XYF) was similar to group D(experimental group with aged refuse and XYF).(4) How aged refuse promote hydrogen production was studied. The results proved that aged refuse play a role as biological-medium and provide various bacteria. Porous structure of aged refuse may affect fermentation type of bio-hydrogen produing from kitchen waste. And microbes supplied by aged refuse improved the utilization of the substrate. Howerver, banding patterns of group A (control group)and group B(experimental group with unpasteurized aged refuse) are similar. Aged refuse may play an important role by optimize the microbial community structure, which needs more research.