Molecular Detection of Biogenic Bacteria During Biogas Production Using Domestic Feed Stock

The
search for a sustainable and environmental friendly energy has resulted to the
development of an alternative renewable energy such as biogas. The objective of
this work was to identify the presence of methanogenic bacteria in a short-term
operated biogas reactor fed with kitchen waste by PCR-amplification of the
methyl coenzyme M reductase (mcrA). Household organic waste was
obtained from Bells University of Technology canteen while pig manure that
served as the inoculum was obtained from a pig farm. Three replicate samples
were taken every week and analysed for changes in the physico-chemical
parameters to determine their effects on the rate of biogas production. Results
obtained showed that the % moisture and carbon contents, before and after
fermentation, were reduced from 88% to 80% and
16.7% to 12.5%, while % nitrogen content increased from 1.20% to 1.70%. The
mean weekly biogas production ranged from 27.4 ml to 147 ml at 4 weeks and 6
weeks, respectively. Methyl coenzyme M reductase
(mcrA) gene, which codes for the enzyme that
catalyse the terminal step in methane production during the anaerobic
fermentation of biomass, was amplified both in
the methanogenic bacteria and transformed E.
coli with the fragment size of 500 bp.