Desulfotomaculum peckii sp. nov., a moderately thermophilic member of the genus Desulfotomaculum, isolated from an upflow anaerobic filter treating abattoir wastewaters.

A novel anaerobic thermophilic sulfate-reducing bacterium designated strain LINDBHT1(T) was isolated from an anaerobic digester treating abattoir wastewaters in Tunisia. Strain LINDBHT1(T) grew at temperatures between 50 and 65 °C (optimum 55-60 °C), and at pH between 5.9 and 9.2 (optimum pH 6.0-6.8). Strain LINDBHT1(T) required salt for growth (1-40 g NaCl l(-1)), with an optimum of 20-30 g l(-1). In the presence of sulfate as terminal electron acceptor, strain LINDBHT1(T) used H2/CO2, propanol, butanol and ethanol as carbon and energy sources but fumarate, formate, lactate and pyruvate were not utilized. Butanol was converted to butyrate, while propanol and ethanol were oxidized to propionate and acetate, respectively. Sulfate, sulfite and thiosulfate were utilized as terminal electron acceptors but elemental sulfur, iron (III), fumarate, nitrate and nitrite were not used. The G+C content of the genomic DNA was 44.4 mol%. Phylogenetic analysis of the small-subunit rRNA gene sequence indicated that strain LINDBHT1(T) was affiliated to the genus Desulfotomaculum with the type strains of Desulfotomaculum halophilum and Desulfotomaculum alkaliphilum as its closest phylogenetic relatives (about 89% similarity). This strain represents a novel species of the genus Desulfotomaculum, Desulfotomaculum peckii sp. nov.; the type strain is LINDBHT1(T) (=DSM 23769(T)=JCM 17209(T)).

Characterization of Defluviitalea saccharophila gen. nov., sp. nov., a thermophilic bacterium isolated from an upflow anaerobic filter treating abattoir wastewaters, and proposal of Defluviitaleaceae fam. nov.

A novel thermophilic, anaerobic, Gram-stain-positive, terminal-spore-forming bacterium was isolated from an upflow anaerobic filter treating abattoir wastewaters in Tunisia. This strain, designated LIND6LT2(T), grew at 40-60 °C (optimum 50-55 °C) and at pH 6.0-8.5 (optimum pH 7.0-7.5). It did not require NaCl for growth, but tolerated it up to 2%. Sulfate, thiosulfate, elemental sulfur, sulfite, nitrate and nitrite were not used as electron acceptors. Growth of LIND6LT2(T) was inhibited by sulfite (2 mM). Strain LIND6LT2(T) used cellobiose, glucose, mannose, maltose, mannitol, sucrose and xylose as electron donors. The main fermentation products from glucose metabolism were acetate, formate, butyrate and isobutyrate. The predominant cellular fatty acids were C(16:0) (68.4%) and C(14:0) (8.3%). The G+C content of the genomic DNA was 35.2 mol%. On the basis of its phylogenetic and physiological properties, a new genus and species, Defluviitalea saccharophila gen. nov., sp. nov., are proposed to accommodate strain LIND6LT2(T), placed in Defluviitaleaceae fam. nov. within the phylum Firmicutes, class Clostridia, order Clostridiales. Strain LIND6LT2(T) (=DSM 22681(T) =JCM 16312(T)) is the type strain of Defluviitalea saccharophila, which itself is the type species of Defluviitalea.

Macellibacteroides fermentans gen. nov., sp. nov., a member of the family Porphyromonadaceae isolated from an upflow anaerobic filter treating abattoir wastewaters.

A novel obligately anaerobic, non-spore-forming, rod-shaped mesophilic bacterium, which stained Gram-positive but showed the typical cell wall structure of Gram-negative bacteria, was isolated from an upflow anaerobic filter treating abattoir wastewaters in Tunisia. The strain, designated LIND7H(T), grew at 20-45 °C (optimum 35-40 °C) and at pH 5.0-8.5 (optimum pH 6.5-7.5). It did not require NaCl for growth, but was able to grow in the presence of up to 2 % NaCl. Sulfate, thiosulfate, elemental sulfur, sulfite, nitrate and nitrite were not used as terminal electron acceptors. Strain LIND7H(T) used cellobiose, glucose, lactose, mannose, maltose, peptone, rhamnose, raffinose, sucrose and xylose as electron donors. The main fermentation products from glucose metabolism were lactate, acetate, butyrate and isobutyrate. The predominant cellular fatty acids were anteiso-C(15 : 0), C(15 : 0), C(17 : 0) 2-OH and a summed feature consisting of C(18 : 2)ω6,9c and/or anteiso-C(18 : 0), and the major menaquinones were MK-9, MK-9(H(2)) and MK-10. The G+C content of the genomic DNA was 41.4 mol%. Although the closest phylogenetic relatives of strain LIND7H(T) were Parabacteroides merdae, Parabacteroides goldsteinii and Parabacteroides gordonii, analysis of the hsp60 gene sequence showed that strain LIND7H(T) was not a member of the genus Parabacteroides. On the basis of phylogenetic inference and phenotypic properties, strain LIND7H(T) ( = CCUG 60892(T) = DSM 23697(T) = JCM 16313(T)) is proposed as the type strain of a novel species in a new genus within the family Porphyromonadaceae, Macellibacteroides fermentans gen. nov., sp. nov.

Bacterial ecology of abattoir wastewater treated by an anaerobic digestor.

Wastewater from an anaerobic treatment plant at a slaughterhouse was analysed to determine the bacterial biodiversity present. Molecular analysis of the anaerobic sludge obtained from the treatment plant showed significant diversity, as 27 different phyla were identified. Firmicutes, Proteobacteria, Bacteroidetes, Thermotogae, Euryarchaeota (methanogens), and msbl6 (candidate division) were the dominant phyla of the anaerobic treatment plant and represented 21.7%, 18.5%, 11.5%, 9.4%, 8.9%, and 8.8% of the total bacteria identified, respectively. The dominant bacteria isolated were Clostridium, Bacteroides, Desulfobulbus, Desulfomicrobium, Desulfovibrio and Desulfotomaculum. Our results revealed the presence of new species, genera and families of microorganisms. The most interesting strains were characterised. Three new bacteria involved in anaerobic digestion of abattoir wastewater were published.

Microbial monitoring by molecular tools of an upflow anaerobic filter treating abattoir wastewaters.

The performance of anaerobic digestion of abattoir wastewaters (AW) in an upflow anaerobic filter (UAF) was investigated under mesophilic (37°C) and thermophilic (55°C) conditions. The effects of increasing temperature on the performance of the UAF and on the dynamics of the microbial community of the anaerobic sludge were studied. The results showed that chemical oxygen demand (COD) removal efficiency of 90% was achieved for organic loading rates (OLRs) up to 4.5g CODL(-1)d(-1) in mesophilic conditions, while in thermophilic conditions, the highest OLRs of 9 g CODL(-1)d(-1) led to the efficiency of 72%. The use of molecular and microbiological methods to recover microbial populations involved in this process showed that fermentative bacteria were the prominent members of the sludge microbial community. Three novel strains were identified as Macellibacteroides fermentans, Desulfotomaculum peckii and Defluviitalea saccharophila.

Bacterial ecology of abattoir wastewater treated by an anaerobic digestor

Abstract Wastewater from an anaerobic treatment plant at a slaughterhouse was analysed to determine the bacterial biodiversity present. Molecular analysis of the anaerobic sludge obtained from the treatment plant showed significant diversity, as 27 different phyla were identified. Firmicutes, Proteobacteria, Bacteroidetes, Thermotogae, Euryarchaeota (methanogens), and msbl6 (candidate division) were the dominant phyla of the anaerobic treatment plant and represented 21.7%, 18.5%, 11.5%, 9.4%, 8.9%, and 8.8% of the total bacteria identified, respectively. The dominant bacteria isolated were Clostridium, Bacteroides, Desulfobulbus, Desulfomicrobium, Desulfovibrio and Desulfotomaculum. Our results revealed the presence of new species, genera and families of microorganisms. The most interesting strains were characterised. Three new bacteria involved in anaerobic digestion of abattoir wastewater were published.