scholarly journals Effect of tannin-rich leaves of oak (Quercus incana) on various microbial enzyme activities of the bovine rumen

1988 ◽  
Vol 60 (2) ◽  
pp. 287-296 ◽  
Author(s):  
H. P. S. Makkar ◽  
B. Singh ◽  
R. K. Dawra
Keyword(s):  
Enzyme Activities ◽  
Solid Matrix ◽  
Forward Reaction ◽  
Bovine Rumen ◽  
Dna And Rna ◽  
Microbial Enzyme ◽  
Micro Organisms ◽  
Oak Leaves

1. The objective of the present experiment was to study the effects of oak (Quercus incana) leaves rich in tannins on various enzyme activities of the bovine rumen.2. The procedure employed was incubation of tannin-rich, very-low-tannin or virtually tannin-free leaves in nylon-gauze bags in the rumen, and determination of enzyme activities in microbes tightly bound to the solid matrix and in microbes loosely plus tightly attached to the solid matrix.3. The activities of urease (EC3.5.1.5), carboxymethylcellulase, glutamate dehydrogenase (EC1.4.1.2) and alanine aminotransferase (glutamic-pyruvic transaminase) (EC2.6.1.2) were significantly lower in the tannin-rich group, whereas the activities of glutamate ammonia ligase (glutamine synthetase) (EC6.3.1.2; both yγ- glutamyltransferase (EC2.3.2.2) and the forward reaction) were higher in the tannin-rich group. These changes were more marked in micro-organisms tightly bound to the solid matrix than in the more complex microbial compartment.4. The protein, DNA and RNA contents, and protein: RNA ratio, were significantly lower in the tannin-rich group, whereas no difference was observed for protein: DNA between the groups.5. Effects of tannin-containing extracts of oak leaves on various rumen enzymes in vitro showed a trend similar to that observed in nylon-gauze bags, suggesting that the changes observed in various compartments were due to the tannins of oak leaves.

scholarly journals Effects of antibiotics on Chlamydia trachomatis viability as determined by real-time quantitative PCR

2011 ◽  
Vol 60 (4) ◽  
pp. 508-514 ◽  
Author(s):  
Olivia Peuchant ◽  
Jean Philippe Duvert ◽  
Maïthé Clerc ◽  
Sophie Raherison ◽  
Christiane Bébéar ◽  
...  
Keyword(s):  
Chlamydia Trachomatis ◽  
Real Time ◽  
Dna Quantification ◽  
Mrna Transcription ◽  
Real Time Quantitative Pcr ◽  
Dna And Rna ◽  
Rna Quantification ◽  
Additional Cell

The objective of this study was to determine the effect of antibiotics on Chlamydia trachomatis viability by using a quantitative real-time PCR assay that measured DNA replication and mRNA transcription of the structural omp1 and omp2 genes, 16S rRNA and the groEL1 gene with and without antibiotics. Ofloxacin, moxifloxacin, azithromycin and doxycycline were tested against the serovar D and L2 reference strains and a derivative mutant resistant to fluoroquinolones, L2-OFXR, obtained by in vitro selection. Using DNA quantification, the antibiotic MIC was calculated when the number of DNA copies was equal to that of the chlamydial inoculum at time zero. This method allowed the easy determination of MICs by DNA quantification of the four selected genes and gave similar results to those obtained by immunofluorescence staining without biased interpretation. By using cDNA quantification, the lowest antibiotic concentration for which no RNA was transcribed corresponded to the minimum bactericidal concentration. C. trachomatis still transcribed the16S rRNA and groEL1 genes, even at concentrations well above the MIC, showing a bacteriostatic effect for all antibiotics tested. This method allows the study of antibiotic activity on growth and viability of C. trachomatis by DNA and RNA quantification at the same time without additional cell-culture passaging.

Comparison of bovine rumen liquor and faeces as sources of micro-organisms for the in vitro gas production technique assessed using twelve graminaceous forages

1998 ◽  
Vol 1998 ◽  
pp. 68-68
Author(s):  
R. Mauricio ◽  
A.L. Abdalla ◽  
F.L. Mould ◽  
U.R. Altaf ◽  
T. Smith ◽  
...  
Keyword(s):  
Pressure Transducer ◽  
Gas Production ◽  
Production Technique ◽  
Bovine Rumen ◽  
In Vitro Gas Production ◽  
Micro Organisms

The experiment was conducted using a range of forages with accurately predetermined OMD values (ADAS) to compare rumen liquor (RL) and faeces (FA) as sources of inocula in the pressure transducer technique (PTT) (Theodorou et al., 1994). Gas production results were examined in relation to OMD determined in vitro (PTT, Tilley and Terry) and in vivo.

Comparison of bovine rumen liquor and bovine faeces as sources of micro-organisms for the in vitro gas production technique for assessing silages of maize and maize plant fractions

1998 ◽  
Vol 1998 ◽  
pp. 60-60
Author(s):  
U.R. Altaf ◽  
R. Mauricio ◽  
F.L. Mould ◽  
T. Smith ◽  
E. Owen ◽  
...  
Keyword(s):  
Organic Matter ◽  
Gas Production ◽  
Maize Plant ◽  
Production Technique ◽  
Maize Silage ◽  
Bovine Rumen ◽  
In Vitro Gas Production ◽  
Organic Matter Digestibility ◽  
Micro Organisms

A previous study (Mauricio et al., 1998) with 12 forage substrates (straw, hay and dried grasses) showed a high correlation between rumen liquor and faeces for total gas production and in vitro organic matter digestibility (OMD). However parameters estimated using faecal inoculum were generally lower man when using rumen liquor. To confirm this observation, a second study was conducted using maize silage and silages made from maize plant fractions.

The use of pivalic acid as a reference substance in measurements of production of volatile fatty acids by rumen micro-organisms in vitro

1976 ◽  
Vol 36 (2) ◽  
pp. 311-315 ◽  
Author(s):  
J. W. Czerkawski
Keyword(s):  
Fatty Acids ◽  
Volatile Fatty Acids ◽  
Pivalic Acid ◽  
Reference Substance ◽  
Micro Organisms

1. A procedure is described for using pivalic acid as an inert reference substance in determination of changes in concentrations of volatile fatty acids (VFA).2. Pivalic acid in concentrations of up to 80 mmol/l had no effect on production of methane or VFA by rumen contents.3. Pivalic acid was inert during incubation with rumen contents from sheep given different diets and with samples taken at different times with respect to feeding.

scholarly journals QUANTITATIVE STUDIES OF PHYTOHEMAGGLUTININ-INDUCED DNA AND RNA SYNTHESIS IN NORMAL AND AGAMMAGLOBULINEMIC LEUKOCYTES

1967 ◽  
Vol 125 (5) ◽  
pp. 863-872 ◽  
Author(s):  
Douglass C. Tormey ◽  
Roberta Kamin ◽  
H. Hugh Fudenberg
Keyword(s):  
Ribonucleic Acid ◽  
Rna Synthesis ◽  
Deoxyribonucleic Acid ◽  
In Vitro Synthesis ◽  
Dna And Rna ◽  
Quantitative Studies ◽  
Precursor Synthesis ◽  
Dna And Rna Synthesis

Leukocytes from nine patients with acquired agammaglobulinemia were studied in vitro. Synthesis of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) induced by phytohemagglutinin was measured by determination of the degree of incorporation of labeled precursor. Synthesis of both DNA and RNA was decreased in the agammaglobulinemic cells. The presence of an inhibitor in the patients' sera could not be demonstrated. These results suggest that the basic defect in agammaglobulinemia is cellular rather than humoral.

Comparison of bovine rumen liquor and faeces as sources of micro-organisms for the in vitro gas production technique assessed using twelve graminaceous forages

1998 ◽  
Vol 1998 ◽  
pp. 68-68 ◽  
Author(s):  
R. Mauricio ◽  
A.L. Abdalla ◽  
F.L. Mould ◽  
U.R. Altaf ◽  
T. Smith ◽  
...  
Keyword(s):  
Pressure Transducer ◽  
Gas Production ◽  
Production Technique ◽  
Bovine Rumen ◽  
In Vitro Gas Production ◽  
Micro Organisms

The experiment was conducted using a range of forages with accurately predetermined OMD values (ADAS) to compare rumen liquor (RL) and faeces (FA) as sources of inocula in the pressure transducer technique (PTT) (Theodorou et al., 1994). Gas production results were examined in relation to OMD determined in vitro (PTT, Tilley and Terry) and in vivo.

Comparison of bovine rumen liquor and bovine faeces as sources of micro-organisms for thein vitrogas production technique for assessing silages of maize and maize plant fractions

1998 ◽  
Vol 1998 ◽  
pp. 60-60 ◽  
Author(s):  
U.R. Altaf ◽  
R. Mauricio ◽  
F.L. Mould ◽  
T. Smith ◽  
E. Owen ◽  
...  
Keyword(s):  
Organic Matter ◽  
Gas Production ◽  
Maize Plant ◽  
Production Technique ◽  
Maize Silage ◽  
Bovine Rumen ◽  
Organic Matter Digestibility ◽  
Micro Organisms

A previous study (Mauricioet al., 1998) with 12 forage substrates (straw, hay and dried grasses) showed a high correlation between rumen liquor and faeces for total gas production andin vitroorganic matter digestibility (OMD). However parameters estimated using faecal inoculum were generally lower man when using rumen liquor. To confirm this observation, a second study was conducted using maize silage and silages made from maize plant fractions.

scholarly journals Killing of adherent oral microbes by a non-thermal atmospheric plasma jet

2010 ◽  
Vol 59 (2) ◽  
pp. 206-212 ◽  
Author(s):  
Stefan Rupf ◽  
Antje Lehmann ◽  
Matthias Hannig ◽  
Barbara Schäfer ◽  
Andreas Schubert ◽  
...  
Keyword(s):  
Plasma Jet ◽  
Plasma Jets ◽  
Atmospheric Plasma ◽  
Killing Effect ◽  
E Coli ◽  
Potential Applications ◽  
Oral Microbes ◽  
Micro Organisms

Atmospheric plasma jets are being intensively studied with respect to potential applications in medicine. The aim of this in vitro study was to test a microwave-powered non-thermal atmospheric plasma jet for its antimicrobial efficacy against adherent oral micro-organisms. Agar plates and dentin slices were inoculated with 6 log10 c.f.u. cm−2 of Lactobacillus casei, Streptococcus mutans and Candida albicans, with Escherichia coli as a control. Areas of 1 cm2 on the agar plates or the complete dentin slices were irradiated with a helium plasma jet for 0.3, 0.6 or 0.9 s mm−2, respectively. The agar plates were incubated at 37 °C, and dentin slices were vortexed in liquid media and suspensions were placed on agar plates. The killing efficacy of the plasma jet was assessed by counting the number of c.f.u. on the irradiated areas of the agar plates, as well as by determination of the number of c.f.u. recovered from dentin slices. A microbe-killing effect was found on the irradiated parts of the agar plates for L. casei, S. mutans, C. albicans and E. coli. The plasma-jet treatment reduced the c.f.u. by 3–4 log10 intervals on the dentin slices in comparison to recovery rates from untreated controls. The microbe-killing effect was correlated with increasing irradiation times. Thus, non-thermal atmospheric plasma jets could be used for the disinfection of dental surfaces.

scholarly journals G-Quadruplex-Based Fluorescent Turn-On Ligands and Aptamers: From Development to Applications

Molecules ◽  
2019 ◽  
Vol 24 (13) ◽  
pp. 2416 ◽  
Author(s):  
Mubarak I. Umar ◽  
Danyang Ji ◽  
Chun-Yin Chan ◽  
Chun Kit Kwok
Keyword(s):  
Interaction Mechanism ◽  
Rna Aptamers ◽  
Rna Sequences ◽  
Turn On ◽  
Dna And Rna ◽  
Cellular Events ◽  
Potential Applications ◽  
Micro Organisms ◽  
Nucleic Acid Structures

Guanine (G)-quadruplexes (G4s) are unique nucleic acid structures that are formed by stacked G-tetrads in G-rich DNA or RNA sequences. G4s have been reported to play significant roles in various cellular events in both macro- and micro-organisms. The identification and characterization of G4s can help to understand their different biological roles and potential applications in diagnosis and therapy. In addition to biophysical and biochemical methods to interrogate G4 formation, G4 fluorescent turn-on ligands can be used to target and visualize G4 formation both in vitro and in cells. Here, we review several representative classes of G4 fluorescent turn-on ligands in terms of their interaction mechanism and application perspectives. Interestingly, G4 structures are commonly identified in DNA and RNA aptamers against targets that include proteins and small molecules, which can be utilized as G4 tools for diverse applications. We therefore also summarize the recent development of G4-containing aptamers and highlight their applications in biosensing, bioimaging, and therapy. Moreover, we discuss the current challenges and future perspectives of G4 fluorescent turn-on ligands and G4-containing aptamers.

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