LAUSR

Abstract Experimental studies have been carried out to find the combined effect of visible light and magnesium (Mg 0 )-metal powder on anaerobic photosynthetic bacteria present in slurry of cowdung and various kinds of organic wastes. The chemical combination of all the above factors helps in producing high quality fuel gas under anaerobic condition. In the fluidized bed reaction, bacteria have been allowed to undergo biophysical and biochemical reactions in the presence of Mg 0 -metal powder under the continuous flow of photons. The source of photons in the biological media is an artificial light (100 W tungsten bulbs) used at 38 °C. Mg 0 -metal powder has been added to the slurry to catalyze the biochemical process in presence of light energy. The population rate of bacteria and composition of fuel gas have been estimated under the action of visible photons in presence and absence of induced Mg 0 -atoms. The fuel gas composition has been measured by Gas-Chromatography and its calorific value measured by flame temperature. Metagenome analysis of consensus ‘V3’-region of 16S rRNA gene amplicons and entire downstream analysis have shown increased bacterial population of Clostridia , Bacteroidia and γ-proteobacteria in presence of Mg 0 -atom. Mg 0 -atom has been observed to activate hydG , mgtE and corA genes of the bacterial community.