Recycling of sawdust to biomethane using bacterial consortia were investigated. The Molecular identification of the bacterial and archaeal isolates based on 16S rRNA gene sequences showed that the dominant bacterial species... more
Recycling of sawdust to biomethane using bacterial consortia were investigated. The Molecular identification of the bacterial and archaeal isolates based on 16S rRNA gene sequences showed that the dominant bacterial species were the Bacillus and Pseudomonas species while Methanosarcina and Methanobrevibacter were the dominant archaeal group. Four bacterial consortia (1, 2, 3 and 4) were formulated by combining the isolates in different ratios. One batch of the organic slurry was
biologically-pre-treated with 1.0% broth culture of Phanarochaete chrysosporium for easy hydrolysis of β-glycosidic and ether-ester bonds of lignocellulose while the other batch was not treated. The results obtained on methane production from 1,600 ml of organic slurry containing 200 grams of pre-treated and untreated substrate each shows that consortium 4 containing more of the Methanogens had the highest methane-producing potential followed by consortia 3, 2 and the least
consortium 1 at different digestion temperatures. The graphical plot of methane yield against different digestion temperatures using the consortia showed that the optimum temperature was 55oC with highest methane yield of 11.80 cm
/g VS and 7.38 cm3/g VS produced by consortium 4 for pre-treated and untreated substrate respectively while the maximum temperature was 65oC with a decline in methane production. One-way analysis of variance of the results obtained from biogas yield shows that methane production was significantly (p ≤ 0) dependent on the microbial consortia,nature of substrates and digestion temperature.
In this study, we isolated seven strains (termed BY1-7) from polluted soil at an oil station and evaluated their abilities to degrade total petroleum hydrocarbons (TPHs). Among 45 bacterial colonies one bacterial strain was identified... more
In this study, we isolated seven strains (termed BY1-7) from polluted soil at an oil station and evaluated their abilities to degrade total petroleum hydrocarbons (TPHs). Among 45 bacterial colonies one bacterial strain was identified based on the cultural, morphological and biochemical characteristics. The isolated bacterium was then subjected to a preliminary assessment of their crude oil after 48 hours of incubation on nutrient agar plates overlaid with 100 ML of petroleum crude oil, the zone of clearance was observed. The isolated bacteria showed 35% petrol degradation, whereas a relatively high oil degradation rate, almost 40% was observed when the bacterium was acclimatized. The selected bacterial strains crude oil resistance was analysed based on the growth ability on the crude oil containing mediums. This strain was identified as Brevibacterium brevis. After inoculation, growth ability was measured and the highest percentage of petrol degradation occurred at temperature 37 °C with the value 30.8%. Bacteria displaying such capabilities are often exploited for the bio-remediation of petroleum oil contaminated environments. Recently, microbial remediation technology has developed rapidly and achieved major gains. However, this technology is not omnipotent. It is affected by many environmental factors that hinder its practical application, limiting the large-scale application of the technology.