Impact Study Of Magnetic Field On Fermentative Biohydrogen Production By E.cloacae And E. Aerogenes

As a prominent representative of clean energy, hydrogen is undoubtedly one of the best in the future. Biohydrogen production by anaerobic fermentation has high hydrogen production efficiency, which were simple and adaptable features. But it is still so difficult to realize industrialization because of all kinds of conditions limiting the hydrogen yield by the method.The relevant research points that the effect of magnetic field can stimulate the cell enzyme activity and growth so that it can promote the degradation of pollutants.Magnetic field being induced into the biohydrogen system with glucose as substrate and bysome analysis approaches, such as detection of dehydrogenase activity and gene sequence, the effect of different magnetic field(magnetic south pole field andmagnetic north and south pole field) and intensity(0m T、8m T、15m T、25m T、42m T、56m T) on biohydrogen of E.cloacae and E.aerogenes and the mechanismwas studiedpreliminarily. The following conclusions were given:(1) E.cloacae had played for promoting growth under magnetic field, which the biomass in the magnetic north pole field of 56 m T condition was 17.5% higher than the blank and the biomass under the 56 m T magnetic north and south pole field condition was improved by 19.1%.(2)Magnetic north and south pole field improved biohydrogen production efficiency of the anaerobic fermentation of glucose: On the conditions of 10g/L glucose, the hydrogen production yields of E.cloacae and E.aerogenes under magnetic north and south pole field of 42 m T were 0.751 and 0.762 mol H2/mol glucose, which were 6.6% and 9% higher than black separately; The maximum hydrogen production rate on the same conditions were 10.27 and 7.31 m L/h, which were increased by 11.5% and 14.9% separately.(3)The data of cumulative hydrogen production by E.cloacae and E.aerogenes were fitted with the Gompertz equation well. Gompertz parameters showed that the cumulative hydrogen production of the two strains under the condition of magnetic north and south pole of 42 m T were 7.9% and 8.7% higher than black separately. The data of degradation of glucose and biomass was fitted with Monod equation very well whether E.aerogenes was on the condition of magnetic field or not.(4)The butanediol generated by E.cloacae and E.aerogenes exposed by magnetic north and south pole field of 42 m T were improved by 34.3% and 12.5%, and the ethanol were improved by 4.5% and 2.9% on the same condition separately. But the biohydrogen production would have to be limited to some extent by those products accumulations.(5)There was no significant effect of magnetic field on appearance and bacterial gene. However, it stimulated dehydrogenase activityas well as cells growth so that the biohydrogen capability of bacteria was enhanced.The maximum biomass of E.cloacae and E.aerogenes exposed by magnetic north and south pole field of 42 m T were increased by 5.1% and 14.4%, and the dehydrogenase activity also were promoted by 8.2% and 20.2% separately.