Faculty Opinions recommendation of Dissimilatory arsenate reductase activity and arsenate-respiring bacteria in bovine rumen fluid, hamster feces, and the termite hindgut.

A strictly anaerobic, mesophilic, endospore-forming, lipolytic bacterium, designated strain R1T, was isolated from bovine rumen fluid and characterized. Cells of this isolate were Gram-positive, non-motile rods that formed spherical terminal spores. The overall biochemical and physiological characteristics indicated that this strain should be placed in the genus Clostridium. The strain grew at temperatures between 25 and 47 °C (optimum, 37 °C), at pH between 5·0 and 8·5 (optimum pH 5·5–7·0) and in NaCl concentrations of 0–3 % (w/v). The isolate was not able to utilize glucose or other carbohydrates as carbon sources. The DNA G+C content was 31·2 mol%. Sequence analysis of the 16S rRNA gene of R1T revealed that it has the closest match (98 % similarity) with Clostridium tetanomorphum DSM 4474T. The highest levels of DNA–DNA relatedness of the isolate were 61·9 and 54·3 % with Clostridium pascui DSM 10365T and C. tetanomorphum DSM 4474T, respectively. Based on 16S rRNA gene sequence similarity, phylogenetic analysis, DNA G+C content, DNA–DNA hybridization data and distinct phenotypic characteristics, strain R1T (=DSM 17049T=CCUG 50446T) was classified in the genus Clostridium, as a member of a novel species, for which the name Clostridium lundense sp. nov. is proposed.

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Can adaptation to nitrate supplementation and provision of fermentable energy reduce nitrite accumulation in rumen contents in vitro?

Animal Production Science ◽

10.1071/an15609 ◽

2016 ◽

Vol 56 (3) ◽

pp. 605 ◽

Cited By ~ 7

Author(s):

V. de Raphélis-Soissan ◽

J. V. Nolan ◽

J. R. Newbold ◽

I. R. Godwin ◽

R. S. Hegarty

Keyword(s):

Rumen Fluid ◽

Reductase Activity ◽

Nitrite Accumulation ◽

Ch4 Production ◽

Urea Nitrate ◽

Nitrite Reductases ◽

Toxicity Risk ◽

Nitrite Reductase Activity ◽

Nitrate Supplementation

Nitrate (NO3–) supplementation is a promising methane mitigation strategy for ruminants, but can cause nitrite (NO2–) poisoning. Because some nitrite reductases are NADH-dependent, we hypothesised that replacing glucose with glycerol would increase the NADH yield and so enhance nitrite reductase activity and reduce ruminal NO2– accumulation and toxicity risk. We also hypothesised that adapting sheep to dietary NO3– would limit the accumulation of NO2– when NO3– was added to rumen fluid. Changes in NO3– and NO2– catabolism and CH4 production, resulting from supplementation with glycerol to enhance NADH supply, were studied in vitro. In Experiment 1, rumen fluid from sheep adapted to dietary NO3– (2% of DM intake) or urea (1.1% of DM intake) was incubated with NO3– or urea, respectively. Additionally, ground oaten hay was added to incubations alone (control), or with glucose or glycerol. In Experiement 2, sheep were adapted for 9 weeks to dietary NO3– or urea. Nitrate (2% NO3– of substrate DM) was added to incubated digesta from NO3–- or urea-supplemented sheep, while urea (1.1% of substrate DM) was added to digesta from urea-supplemented sheep. In both studies, triplicate incubations were terminated at nine time points up to 24 h. Methane emissions were lower in all NO3– treatments (P < 0.05). Contrary to our hypotheses, both glycerol supplementation (Experiment 1) and prior adaptation to NO3– (Experiment 2) increased NO2– accumulation. In Experiment 1, there was no difference in ruminal NO2– concentration between the unsupplemented control and added glucose treatments. Nitrous oxide accumulated in NO3– treatments only with rumen fluid from sheep adapted to dietary urea (P < 0.05). In summary, NO2– accumulation in vitro was not reduced by adaptation to NO3– or by glucose or glycerol supplementation, disproving the hypotheses regarding the role of NADH availability and of NO2– adaptation in reducing ruminal NO2– accumulation and toxicity risk.

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Functional analysis of ars gene cluster of Pannonibacter indicus strain HT23T (DSM 23407T) and identification of a proline residue essential for arsenate reductase activity

Applied Microbiology and Biotechnology ◽

10.1007/s00253-016-7390-2 ◽

2016 ◽

Vol 100 (7) ◽

pp. 3235-3244 ◽

Cited By ~ 3

Author(s):

Saumya Bandyopadhyay ◽

Subrata K. Das

Keyword(s):

Functional Analysis ◽

Gene Cluster ◽

Reductase Activity ◽

Arsenate Reductase ◽

Proline Residue

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Lysis of Viable Rumen Bacteria in Bovine Rumen Fluid

Applied Microbiology ◽

10.1128/aem.16.5.714-723.1968 ◽

1968 ◽

Vol 16 (5) ◽

pp. 714-723 ◽

Cited By ~ 22

Author(s):

B. D. W. Jarvis

Keyword(s):

Rumen Fluid ◽

Rumen Bacteria ◽

Bovine Rumen

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Identification and Characterization Indigenous of Lactobacillus spfrom Bovine Rumen Fluidof Slaughterhouse

KnE Life Sciences ◽

10.18502/kls.v3i6.1182 ◽

2017 ◽

Vol 3 (6) ◽

pp. 549

Author(s):

Tri Nurhajati ◽

Koesnoto Soepranianondo ◽

Widya Paramita Lokapirnasari ◽

Adriana Monica Sahidu

Keyword(s):

Lactic Acid ◽

Nucleotide Sequence ◽

Lactic Acid Bacteria ◽

16S Rdna ◽

Biochemical Characterization ◽

Rumen Fluid ◽

Lactobacillus Rhamnosus ◽

Bovine Rumen ◽

Pcr Method

The discovery and characterisation of indigenous lactic acid bacteria (LAB) are important for diversity microbes as candidate probiotic. This research was aimed to identify lactic acid bacteria isolate from isolation process of local bovine rumen fluid from slaughterhouse in Surabaya Indonesia. Genotypic testing was conducted by analyzing 16S rDNA and biochemical identification. DNA of sample isolate was isolated and then amplified in vitro through the PCR method. Determination of nucleotide sequence of 16S rDNA was performed with sequencing method. The result of nucleotide sequence was than compared with GenBank database. The BLAST was then applied to identify the phylogenetic tree. Based on the biochemical characterization and nucleotide sequences, that isolate was identified as Lactobacillus rhamnosus subsp TG15. The result of this research showed that L.rhamnosus subsp TG15 showed viability bacteria in MRSA as control as much as 1.1 x 108 CFU/ml, mean while in MRSA pH 2, L.rhamnosus subsp TG15 showed its viability as much as 9.3 x 106 CFU/ml. Viability of isolate on bile tolerance 0.3% was 2.4 x 107 CFU/ml). Index antagonist bacteria test on S.aureus showed inhibition diameter as much as 2.0 mm and in antagonist test on E.coli as much as 2.5 mm. Based on the result, it could be concluded that this research found a new strain of lactic acid bacteria, L.rhamnosus subsp TG15 and that isolate has ability as the probiotic candidate. Keywords: L.rhamnosus subsp TG15; survival on acidity; bile salts; S.aureus and E.coli

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In Vitro Inactivation of Escherichia coli O157:H7 in Bovine Rumen Fluid by Caprylic Acid

Journal of Food Protection ◽

10.4315/0362-028x-67.5.884 ◽

2004 ◽

Vol 67 (5) ◽

pp. 884-888 ◽

Cited By ~ 26

Author(s):

THIRUNAVUKKARASU ANNAMALAI ◽

MANOJ KUMAR MOHAN NAIR ◽

PATRICK MAREK ◽

PRADEEP VASUDEVAN ◽

DAVID SCHREIBER ◽

...

Keyword(s):

Escherichia Coli ◽

Caprylic Acid ◽

Rumen Fluid ◽

Bacterial Load ◽

Anaerobic Bacteria ◽

Inhibitory Effect ◽

Escherichia Coli O157 ◽

E Coli ◽

Bovine Rumen

The antibacterial effect of caprylic acid (35 and 50 mM) on Escherichia coli O157:H7 and total anaerobic bacteria at 39° C in rumen fluid (pH 5.6 and 6.8) from 12 beef cattle was investigated. The treatments containing caprylic acid at both pHs significantly reduced (P < 0.05) the population of E. coli O157:H7 compared with that in the control samples. At pH 5.6, both levels of caprylic acid killed E. coli O157:H7 rapidly, reducing the pathogen population to undetectable levels at 1 min of incubation (a more than 6.0-log CFU/ml reduction). In buffered rumen fluid at pH 6.8, 50 mM caprylic acid reduced the E. coli O157:H7 population to undetectable levels at 1 min of incubation, whereas 35 mM caprylic acid reduced the pathogen by approximately 3.0 and 5.0 log CFU/ml at 8 and 24 h of incubation, respectively. At both pHs, caprylic acid had a significantly lesser (P < 0.05) and minimal inhibitory effect on the population of total anaerobic bacteria in rumen compared with that on E. coli O157:H7. At 24 h of incubation, caprylic acid (35 and 50 mM) reduced the population of total anaerobic bacteria by approximately 2.0 log CFU/ml at pH 5.6, whereas at pH 6.8, caprylic acid (35 mM) did not have any significant (P > 0.05) inhibitory effect on total bacterial load. Results of this study revealed that caprylic acid was effective in inactivating E. coli O157:H7 in bovine rumen fluid, thereby justifying its potential as a preslaughter dietary supplement for reducing pathogen carriage in cattle.

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