Sludge samples were collected from a wastewater treatment plant in Nigeria for characterization a... more Sludge samples were collected from a wastewater treatment plant in Nigeria for characterization and evaluation for agricultural applications. Conventional and Molecular techniques were adopted for the isolation and identification of indigenous microorganisms and resulting isolates were characterized and identified by consulting Bergey’s manual of determinative bacteriology and subjected to further screenings to assess their biofertilizer potential using standard microbiological techniques. The viable cells obtained were enumerated and were found to be in the range of 1.03 ± 0.09 x103 cfu/g to 7.45 ± 0.78 x103 cfu/g for heterotrophic Bacteria and 1.63 ± 0.74 x103 cfu/g for fungal community. The Molecular analysis carried out revealed a rich assemblage of diverse species of microorganisms with Bacteria (99.40%) being the most dominant group, followed by Fungi (0.39%) and others (0.21%). Thirty (30) isolates belonging to four (4) Phyla was recovered culturally and identified with Firmi...
Comparative assays were conducted to assess the biogas and biofertilizer production efficiency fr... more Comparative assays were conducted to assess the biogas and biofertilizer production efficiency from anaerobically codigested goat manure (GM) and harvest residues: corn stover (CS) and rice straw (RS). All digesters were operated simultaneously under mesophilic temperature of 40°C and notable phosphate solubilizing and nitrogen fixing bacterial populations indicated qualitative biofertilizer quality of the digestates. Codigestion of the substrates significantly increased biogas yield (p < 0.05) compared to monodigestion, and the highest cumulative yield of 573 ml/g VS was obtained from codigested rice straw (RS) and goat manure (GM). With a significant decimation in number of pathogens (p < 0.05), a 2 – 3 fold increase in populations of plant growth promoting bacteria (Bacillus and Pseudomonas species) was observed in digestate from codigestion assays when compared to monodigestion (control) and were identified as Clostridium sp., Bacillus subtilis, Bacillus megaterium, Lactob...
Laboratory-scale bioreactors were used to co-digest spent coconut copra (SCC) and cow urine (CU) ... more Laboratory-scale bioreactors were used to co-digest spent coconut copra (SCC) and cow urine (CU) as a co-substrate (SCC + CU) in a batch mode under thermophilic condition (45 ± 2°C) in order to enhance biogas production. The effect of CU pretreatment on the performance indicators (biogas and biomethane yields, total solids (TS), and volatile solids (VS) reduction, pH and volatile fatty acids (VFAs) concentrations) were also examined. This was compared with mono-digestion of SCC. The experiment was performed with different mixing ratios in reactors labelled as follows: A = 75 g SCC + 5 ml CU; B = 70 g SCC + 10 ml CU; C = 65 g SCC + 15 ml CU; and D (control) = 80 g SCC at a hydraulic retention time of 42 days. Co-digestion (SCC + CU) significantly improved anaerobic digestion (AD) performance resulting in a threefold and fivefold increase in biogas and biomethane production, respectively, with concomitant TS (44.9–57.7%) and VS (55.4–60.3%) removal efficiencies. But for mono-digestion...
This study evaluated using 16S rDNA gene-based metagenomics technique the populations of bacteria... more This study evaluated using 16S rDNA gene-based metagenomics technique the populations of bacteria and archaea in digestate samples from lab-scale anaerobic bioreactors digesting pretreated and untreated coconut husk fiber, pineapple floret and banana stem. Result of biodegradability experiment indicated high microbial activity in digestate (biogas slurry), with untreated banana stem having the highest total solids (TS) and volatile solids (VS) removal efficiencies of 78.3 % and 92.9 % respectively. Similarly, all pretreated substrates exhibited higher TS and VS losses with corresponding TS (77.8 %) and VS (87.2 %) removal efficiencies. This TS and VS removal rates signaled increased rate of organic matter decomposition with concomitant biogas productivity. Diversity comparisons performed between samples showed rich microbial diversity in untreated sample than the pretreated sample. Taxonomic composition revealed that, for untreated samples at the phylum level, the bacterial communit...
Anaerobic codigestion (AcD) of agroindustrial residues was investigated. Granular sludge from ben... more Anaerobic codigestion (AcD) of agroindustrial residues was investigated. Granular sludge from bench-scale bioreactors digesting different manure were acclimated and recycled as microbial seed sludge to demonstrate inoculum-type influence on digestion performance. The biomethane potential (BMP) assay was operated for 30 days at 40 ± 2 °C in batch-type laboratory-scale reactors (100 mL). In inoculum amended reactors, codigestion showed significant, yet distinctive, biomethanation than monodigestion with a 5-fold increase (p < 0.05) in average biogas (248.3 ± 5.30 mL gVS-1) and CH4 yield (207.5 ± 4.15 mL gVS-1). The pH, soluble chemical oxygen demand (sCOD) and volatile fatty acids (VFAs) concentrations were within limits for stable AcD process with elevated total solids (TS) and volatile solids (VS) removal efficiencies. This study reinforces advancements in the recycling of digestate in biodigesters and suggests the appropriate selection of inoculum, preferably cow manure, to esse...
Effect of surfaces of earthenware pots, glass, plastic and stainless steel containers on the phys... more Effect of surfaces of earthenware pots, glass, plastic and stainless steel containers on the physicochemical and bacteriological (biofilm formation) quality of borehole and atmospheric water stored for twelve days were determined using standard analytical and bacteriological techniques. Susceptibility of the bacterial isolates to different antibiotics was also determined using standard Kirby-Bauer agar disc diffusion procedures. The physicochemical parameters determined for borehole water sample were within WHO permissible standard while rain water sample recorded slightly higher values for NO3 - , and NO2 (10.2 mgL -1 and 0.045 mgL -1 respectively) than WHO standards of 10 mgL -1 and 0.02 mgL -1 respectively. Biofilm bacterial communities from stored borehole water consisted of nine genera including Pseudomonas, Micrococcus, Klebsiella, Bacillus, Staphylococcus, Escherichia, Proteus, Serratia, and Enterobacter. The recovery rate of the various bacterial genera were 40% in earthenwa...
Sludge samples were collected from a wastewater treatment plant in Nigeria for characterization a... more Sludge samples were collected from a wastewater treatment plant in Nigeria for characterization and evaluation for agricultural applications. Conventional and Molecular techniques were adopted for the isolation and identification of indigenous microorganisms and resulting isolates were characterized and identified by consulting Bergey’s manual of determinative bacteriology and subjected to further screenings to assess their biofertilizer potential using standard microbiological techniques. The viable cells obtained were enumerated and were found to be in the range of 1.03 ± 0.09 x10 cfu/g to 7.45 ± 0.78 x10 cfu/g for heterotrophic Bacteria and 1.63 ± 0.74 x10 cfu/g for fungal community. The Molecular analysis carried out revealed a rich assemblage of diverse species of microorganisms with Bacteria (99.40%) being the most dominant group, followed by Fungi (0.39%) and others (0.21%). Thirty (30) isolates belonging to four (4) Phyla was recovered culturally and identified with Firmicut...
Journal of Chemical, Environmental and Biological Engineering
A microbial composition study of sediments of contaminated (CWS) and uncontaminated (UWS) lentic ... more A microbial composition study of sediments of contaminated (CWS) and uncontaminated (UWS) lentic ecosystems within Akwa Ibom State was carried out by analyzing the small-subunit rRNA genes to determine the effect of hydrocarbon contamination on its microbial composition and diversity. Analysis of the V4 region of the community DNA from both sediments revealed the presence of bacteria, archaea and microalgae. Bacterial sequences outnumbered archaea and microalgae. Abundance of Proteobacteria, Betaproteobacteria, Burholderiales, Alcaligenaceae, and Achrombacter were observed in the CWS and Actinobacteria, Actinomycetales, Bacillaceae, and Bacillus in the UWS. Crenarchaeota and Euryarchaeota were also observed to be present in both sediments. The genus Achromobacter and Bacillus dominated in the
This study evaluated using 16S rDNA gene-based metagenomics technique the populations of bacteria... more This study evaluated using 16S rDNA gene-based metagenomics technique the populations of bacteria and archaea in digestate samples from lab-scale anaerobic bioreactors digesting pretreated and untreated coconut husk fiber, pineapple floret and banana stem. Result of biodegradability experiment indicated high microbial activity in digestate (biogas slurry), with untreated banana stem having the highest total solids (TS) and volatile solids (VS) removal efficiencies of 78.3 % and 92.9 % respectively. Similarly, all pretreated substrates exhibited higher TS and VS losses with corresponding TS (77.8 %) and VS (87.2 %) removal efficiencies. This TS and VS removal rates signaled increased rate of organic matter decomposition with concomitant biogas productivity. Diversity comparisons performed between samples showed rich microbial diversity in untreated sample than the pretreated sample. Taxonomic composition revealed that, for untreated samples at the phylum level, the bacterial communit...
Comparative assays were conducted to assess the biogas and biofertilizer production efficiency fr... more Comparative assays were conducted to assess the biogas and biofertilizer production efficiency from anaerobically codigested goat manure (GM) and harvest residues: corn stover (CS) and rice straw (RS). All digesters were operated simultaneously under mesophilic temperature of 40°C and notable phosphate solubilizing and nitrogen fixing bacterial populations indicated qualitative biofertilizer quality of the digestates. Codigestion of the substrates significantly increased biogas yield (p < 0.05) compared to monodigestion, and the highest cumulative yield of 573 ml/g VS was obtained from codigested rice straw (RS) and goat manure (GM). With a significant decimation in number of pathogens (p < 0.05), a 2 – 3 fold increase in populations of plant growth promoting bacteria (Bacillus and Pseudomonas species) was observed in digestate from codigestion assays when compared to monodigestion (control) and were identified as Clostridium sp., Bacillus subtilis, Bacillus megaterium, Lactob...
Sludge samples were collected from a wastewater treatment plant in Nigeria for characterization a... more Sludge samples were collected from a wastewater treatment plant in Nigeria for characterization and evaluation for agricultural applications. Conventional and Molecular techniques were adopted for the isolation and identification of indigenous microorganisms and resulting isolates were characterized and identified by consulting Bergey’s manual of determinative bacteriology and subjected to further screenings to assess their biofertilizer potential using standard microbiological techniques. The viable cells obtained were enumerated and were found to be in the range of 1.03 ± 0.09 x103 cfu/g to 7.45 ± 0.78 x103 cfu/g for heterotrophic Bacteria and 1.63 ± 0.74 x103 cfu/g for fungal community. The Molecular analysis carried out revealed a rich assemblage of diverse species of microorganisms with Bacteria (99.40%) being the most dominant group, followed by Fungi (0.39%) and others (0.21%). Thirty (30) isolates belonging to four (4) Phyla was recovered culturally and identified with Firmi...
Comparative assays were conducted to assess the biogas and biofertilizer production efficiency fr... more Comparative assays were conducted to assess the biogas and biofertilizer production efficiency from anaerobically codigested goat manure (GM) and harvest residues: corn stover (CS) and rice straw (RS). All digesters were operated simultaneously under mesophilic temperature of 40°C and notable phosphate solubilizing and nitrogen fixing bacterial populations indicated qualitative biofertilizer quality of the digestates. Codigestion of the substrates significantly increased biogas yield (p < 0.05) compared to monodigestion, and the highest cumulative yield of 573 ml/g VS was obtained from codigested rice straw (RS) and goat manure (GM). With a significant decimation in number of pathogens (p < 0.05), a 2 – 3 fold increase in populations of plant growth promoting bacteria (Bacillus and Pseudomonas species) was observed in digestate from codigestion assays when compared to monodigestion (control) and were identified as Clostridium sp., Bacillus subtilis, Bacillus megaterium, Lactob...
Laboratory-scale bioreactors were used to co-digest spent coconut copra (SCC) and cow urine (CU) ... more Laboratory-scale bioreactors were used to co-digest spent coconut copra (SCC) and cow urine (CU) as a co-substrate (SCC + CU) in a batch mode under thermophilic condition (45 ± 2°C) in order to enhance biogas production. The effect of CU pretreatment on the performance indicators (biogas and biomethane yields, total solids (TS), and volatile solids (VS) reduction, pH and volatile fatty acids (VFAs) concentrations) were also examined. This was compared with mono-digestion of SCC. The experiment was performed with different mixing ratios in reactors labelled as follows: A = 75 g SCC + 5 ml CU; B = 70 g SCC + 10 ml CU; C = 65 g SCC + 15 ml CU; and D (control) = 80 g SCC at a hydraulic retention time of 42 days. Co-digestion (SCC + CU) significantly improved anaerobic digestion (AD) performance resulting in a threefold and fivefold increase in biogas and biomethane production, respectively, with concomitant TS (44.9–57.7%) and VS (55.4–60.3%) removal efficiencies. But for mono-digestion...
This study evaluated using 16S rDNA gene-based metagenomics technique the populations of bacteria... more This study evaluated using 16S rDNA gene-based metagenomics technique the populations of bacteria and archaea in digestate samples from lab-scale anaerobic bioreactors digesting pretreated and untreated coconut husk fiber, pineapple floret and banana stem. Result of biodegradability experiment indicated high microbial activity in digestate (biogas slurry), with untreated banana stem having the highest total solids (TS) and volatile solids (VS) removal efficiencies of 78.3 % and 92.9 % respectively. Similarly, all pretreated substrates exhibited higher TS and VS losses with corresponding TS (77.8 %) and VS (87.2 %) removal efficiencies. This TS and VS removal rates signaled increased rate of organic matter decomposition with concomitant biogas productivity. Diversity comparisons performed between samples showed rich microbial diversity in untreated sample than the pretreated sample. Taxonomic composition revealed that, for untreated samples at the phylum level, the bacterial communit...
Anaerobic codigestion (AcD) of agroindustrial residues was investigated. Granular sludge from ben... more Anaerobic codigestion (AcD) of agroindustrial residues was investigated. Granular sludge from bench-scale bioreactors digesting different manure were acclimated and recycled as microbial seed sludge to demonstrate inoculum-type influence on digestion performance. The biomethane potential (BMP) assay was operated for 30 days at 40 ± 2 °C in batch-type laboratory-scale reactors (100 mL). In inoculum amended reactors, codigestion showed significant, yet distinctive, biomethanation than monodigestion with a 5-fold increase (p < 0.05) in average biogas (248.3 ± 5.30 mL gVS-1) and CH4 yield (207.5 ± 4.15 mL gVS-1). The pH, soluble chemical oxygen demand (sCOD) and volatile fatty acids (VFAs) concentrations were within limits for stable AcD process with elevated total solids (TS) and volatile solids (VS) removal efficiencies. This study reinforces advancements in the recycling of digestate in biodigesters and suggests the appropriate selection of inoculum, preferably cow manure, to esse...
Effect of surfaces of earthenware pots, glass, plastic and stainless steel containers on the phys... more Effect of surfaces of earthenware pots, glass, plastic and stainless steel containers on the physicochemical and bacteriological (biofilm formation) quality of borehole and atmospheric water stored for twelve days were determined using standard analytical and bacteriological techniques. Susceptibility of the bacterial isolates to different antibiotics was also determined using standard Kirby-Bauer agar disc diffusion procedures. The physicochemical parameters determined for borehole water sample were within WHO permissible standard while rain water sample recorded slightly higher values for NO3 - , and NO2 (10.2 mgL -1 and 0.045 mgL -1 respectively) than WHO standards of 10 mgL -1 and 0.02 mgL -1 respectively. Biofilm bacterial communities from stored borehole water consisted of nine genera including Pseudomonas, Micrococcus, Klebsiella, Bacillus, Staphylococcus, Escherichia, Proteus, Serratia, and Enterobacter. The recovery rate of the various bacterial genera were 40% in earthenwa...
Sludge samples were collected from a wastewater treatment plant in Nigeria for characterization a... more Sludge samples were collected from a wastewater treatment plant in Nigeria for characterization and evaluation for agricultural applications. Conventional and Molecular techniques were adopted for the isolation and identification of indigenous microorganisms and resulting isolates were characterized and identified by consulting Bergey’s manual of determinative bacteriology and subjected to further screenings to assess their biofertilizer potential using standard microbiological techniques. The viable cells obtained were enumerated and were found to be in the range of 1.03 ± 0.09 x10 cfu/g to 7.45 ± 0.78 x10 cfu/g for heterotrophic Bacteria and 1.63 ± 0.74 x10 cfu/g for fungal community. The Molecular analysis carried out revealed a rich assemblage of diverse species of microorganisms with Bacteria (99.40%) being the most dominant group, followed by Fungi (0.39%) and others (0.21%). Thirty (30) isolates belonging to four (4) Phyla was recovered culturally and identified with Firmicut...
Journal of Chemical, Environmental and Biological Engineering
A microbial composition study of sediments of contaminated (CWS) and uncontaminated (UWS) lentic ... more A microbial composition study of sediments of contaminated (CWS) and uncontaminated (UWS) lentic ecosystems within Akwa Ibom State was carried out by analyzing the small-subunit rRNA genes to determine the effect of hydrocarbon contamination on its microbial composition and diversity. Analysis of the V4 region of the community DNA from both sediments revealed the presence of bacteria, archaea and microalgae. Bacterial sequences outnumbered archaea and microalgae. Abundance of Proteobacteria, Betaproteobacteria, Burholderiales, Alcaligenaceae, and Achrombacter were observed in the CWS and Actinobacteria, Actinomycetales, Bacillaceae, and Bacillus in the UWS. Crenarchaeota and Euryarchaeota were also observed to be present in both sediments. The genus Achromobacter and Bacillus dominated in the
This study evaluated using 16S rDNA gene-based metagenomics technique the populations of bacteria... more This study evaluated using 16S rDNA gene-based metagenomics technique the populations of bacteria and archaea in digestate samples from lab-scale anaerobic bioreactors digesting pretreated and untreated coconut husk fiber, pineapple floret and banana stem. Result of biodegradability experiment indicated high microbial activity in digestate (biogas slurry), with untreated banana stem having the highest total solids (TS) and volatile solids (VS) removal efficiencies of 78.3 % and 92.9 % respectively. Similarly, all pretreated substrates exhibited higher TS and VS losses with corresponding TS (77.8 %) and VS (87.2 %) removal efficiencies. This TS and VS removal rates signaled increased rate of organic matter decomposition with concomitant biogas productivity. Diversity comparisons performed between samples showed rich microbial diversity in untreated sample than the pretreated sample. Taxonomic composition revealed that, for untreated samples at the phylum level, the bacterial communit...
Comparative assays were conducted to assess the biogas and biofertilizer production efficiency fr... more Comparative assays were conducted to assess the biogas and biofertilizer production efficiency from anaerobically codigested goat manure (GM) and harvest residues: corn stover (CS) and rice straw (RS). All digesters were operated simultaneously under mesophilic temperature of 40°C and notable phosphate solubilizing and nitrogen fixing bacterial populations indicated qualitative biofertilizer quality of the digestates. Codigestion of the substrates significantly increased biogas yield (p < 0.05) compared to monodigestion, and the highest cumulative yield of 573 ml/g VS was obtained from codigested rice straw (RS) and goat manure (GM). With a significant decimation in number of pathogens (p < 0.05), a 2 – 3 fold increase in populations of plant growth promoting bacteria (Bacillus and Pseudomonas species) was observed in digestate from codigestion assays when compared to monodigestion (control) and were identified as Clostridium sp., Bacillus subtilis, Bacillus megaterium, Lactob...
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