Total reductive dechlorination of chlorobenzenes to benzene by a methanogenic mixed culture enriched from Saale river sediment

1996 ◽  
Vol 45 (5) ◽  
pp. 700-709 ◽  
Author(s):  
J. Nowak ◽  
N. H. Kirsch ◽  
W. Hegemann ◽  
H.-J. Stan
Keyword(s):  
Mixed Culture ◽  
Reductive Dechlorination ◽  
River Sediment

scholarly journals Characterization of a Highly Enriched Microbial Consortium Reductively Dechlorinating 2,3-Dichlorophenol and 2,4,6-Trichlorophenol and the Corresponding cprA Genes from River Sediment

2016 ◽  
Vol 65 (3) ◽  
pp. 341-352 ◽  
Author(s):  
Wael S. El-Sayed
Keyword(s):  
Electron Donor ◽  
Reductive Dechlorination ◽  
River Sediment ◽  
Microbial Consortium ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Bacterial Species ◽  
Rrna Gene ◽  
Gradient Gel Electrophoresis ◽  
Dominant Bacteria

Anaerobic reductive dechlorination of 2,3-dichlorophenol (2,3DCP) and 2,4,6-trichlorophenol (2,4,6TCP) was investigated in microcosms from River Nile sediment. A stable sediment-free anaerobic microbial consortium reductively dechlorinating 2,3DCP and 2,4,6TCP was established. Defined sediment-free cultures showing stable dechlorination were restricted to ortho chlorine when enriched with hydrogen as the electron donor, acetate as the carbon source, and either 2,3-DCP or 2,4,6-TCP as electron acceptors. When acetate, formate, or pyruvate were used as electron donors, dechlorination activity was lost. Only lactate can replace dihydrogen as an electron donor. However, the dechlorination potential was decreased after successive transfers. To reveal chlororespiring species, the microbial community structure of chlorophenol-reductive dechlorinating enrichment cultures was analyzed by PCR-denaturing gradient gel electrophoresis (DGGE) of 16S rRNA gene fragments. Eight dominant bacteria were detected in the dechlorinating microcosms including members of the genera Citrobacter, Geobacter, Pseudomonas, Desulfitobacterium, Desulfovibrio, and Clostridium. Highly enriched dechlorinating cultures were dominated by four bacterial species belonging to the genera Pseudomonas, Desulfitobacterium, and Clostridium. Desulfitobacterium represented the major fraction in DGGE profiles indicating its importance in dechlorination activity, which was further confirmed by its absence resulting in complete loss of dechlorination. Reductive dechlorination was confirmed by the stoichiometric dechlorination of 2,3DCP and 2,4,6TCP to metabolites with less chloride groups and by the detection of chlorophenol RD cprA gene fragments in dechlorinating cultures. PCR amplified cprA gene fragments were cloned and sequenced and found to cluster with the cprA/pceA type genes of Dehalobacter restrictus.

scholarly journals Microbially enhanced dissolution and reductive dechlorination of PCE by a mixed culture: Model validation and sensitivity analysis

2013 ◽  
Vol 151 ◽  
pp. 117-130 ◽  
Author(s):  
Mingjie Chen ◽  
Linda M. Abriola ◽  
Benjamin K. Amos ◽  
Eric J. Suchomel ◽  
Kurt D. Pennell ◽  
...  
Keyword(s):  
Sensitivity Analysis ◽  
Mixed Culture ◽  
Model Validation ◽  
Reductive Dechlorination ◽  
Enhanced Dissolution ◽  
Culture Model

Impact of Transfaunation of Rumen Ciliate Cultures on Physical Examination, Selected Serum Parameters and Milk Profile in Defaunated Lactating Dairy Goats

2020 ◽  
Keyword(s):  
Physical Examination ◽  
Mixed Culture ◽  
Pure Culture ◽  
Milk Fat ◽  
Mixed Cultures ◽  
Dairy Goats ◽  
Serum Parameters ◽  
Native Breed ◽  
Culture Duration ◽  
Inorganic Phosphorous

Rumen ciliates still have mysterious secrets and influences in ruminants. This study investigated the effect of transfaunation of pure and mixed cultures of rumen ciliates on physical clinical examination, selected serum parameters and milk profile in defaunated lactating dairy goats. A number of 8 Baladi native breed goats were randomly classified into two groups each one containing 4 goats. Pure culture group was transfaunated with 6 ml of pure culture of Holotricha spp., while mixed culture group was transfaunated with 6 ml of mixed culture of 81.85% Holotricha and 18.15% Ophryoscolex spp. once weekly for three consecutive weeks, after defaunation of both groups using 30 ml of 8% SLS for two consecutive days. Serum and milk samples were collected weekly for three successive weeks to study effect of type of ciliate culture, duration of transfaunation and their interaction. Results revealed that transfaunation of pure and mixed cultures of rumen ciliates had no effect on physical examination with minimal non-significant improvement of calcium, inorganic phosphorous, total protein and globulin in serum of defaunated goats. Transfaunation of pure or mixed cultures of rumen ciliates within three weeks could not improve significantly decreased milk fat % of defaunated goats without any effect on other measured milk profile parameters. It is concluded that further investigations on transfaunation without prior defaunation should be performed using different pure and mixed cultures of rumen ciliates for therapeutic and productive purposes.

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