Abstract:

Low temperature conditions, cow dung methane gas production peak structure of methane-producing bacteria flora, using molecular biology 16S rDNA gene library, research dung biogas fermentation flora methanogens. Structure analysis of 60 randomLy cloned library 16S rDNA gene sequence, was found in 60 clones belonging to 18 genera (Methanosarcina sp.). With one of (Methanosarcina sp.)AK-16 strain of the highest degree of homology, similarity of 99%. 7 of which are Division Methanosarcinales Methanosarcina strains the highest degree of homology, similarity of 99%, 15 belong to the genus Methanosaeta strains of methane mane highest degree of homology, similarity of 99% use software to analyze 60 MEGA4.0 cloned 16S rRNA sequences to construct the corresponding phylogenetic the showed that was divided into two groups, namely Group A and Group B. Which belongs to genus Methanosarcina as Methanosarcina sp. major groups, accounting for 42% of all clones, the other part of the genus Methanosaeta mane of methane as the main group, accounting for 25%. Throughout the fermentation period in the first 18 days until the feed gas production reached its peak. With later after the peak of gas production, gas production decreased to 49 days of the decline in methane gas production also decreased 21%. A period equivalent to the total gas production 504.91 mL 8 m3 21.71 m3 fermentation gas production total of which 62% of methane gas. Low temperature (4℃) under the conditions of the fermentation of cow dung as the main raw material for biogas production peak period of the advantages of methanogenic bacteria, and found a Methanosarcina Methanosarcina sp. accounted for 42% of the total.