scholarly journals Distribution and changes in urease (EC3.5.1.5) activity in Rumen Simulation Technique (Rusitec)

1982 ◽  
Vol 47 (2) ◽  
pp. 331-348 ◽  
Author(s):  
J. W. Czerkawski ◽  
Grace Breckenridge
Keyword(s):  
Alkaline Phosphatase ◽  
Volatile Fatty Acids ◽  
Urease Activity ◽  
Boundary Region ◽  
Simulation Technique ◽  
Unit Weight ◽  
Solid Matrix ◽  
Direct Function ◽  
Micro Organisms ◽  
Reaction Vessels

1. The Rumen Simulation Technique (Rusitec) was used in a series of long-term experiments to study the distribution and changes of urease (EC3.5.1.5) activity in a heterogeneous fermentation system.2. It was shown that in Rusitec the high urease activity from the inoculum decreased to low values, that the rate of decrease was consistent with simple dilution of ureolytic micro-organisms and that the urease activity could be restored to original values by infusion of urea into the reaction vessels. The magnitude of this urease activity was a direct function of the amounts of urea infused. Single daily additions of the same or greater amounts of urea in food or as solid failed to increase the urease activity significantly.3. In general, urease activity increased 2–6 h after feeding and the increases were greater with roughage diets.4. The ureolytic activity per unit volume was always higher in compartment 2 (space occupied by micro-organisms that are loosely associated with the solid) than in compartment 1 (strained rumen contents) or compartment 3 (space occupied by microbial population that cannot be washed out of the solid matrix).5. The distribution of urease activity between the compartments was different from the distribution of certain other enzymes (e.g. protease and alkaline phosphatase (EC3.1.3.1)).6. Apart from the boundary region, the concentrations of urease, ammonia and volatile fatty acids in compartment 2 were constant, while the concentrations of protein, DNA and another enzyme (alkaline phosphatase) increased with the depth of the compartment. Specific urease activity (per unit weight of protein or DNA) was much higher in compartment 1 than in compartment 2 and it decreased markedly with depth of compartment.7. The concentrations of ammonia were always much higher in the solid matrix (compartments 2 and 3) than in the free suspension of micro-organisms (compartment 1). There was a linear relation between these two quantities.8. The results are discussed in relation to published work on the entry and metabolism of urea in the rumen.

scholarly journals Experiments with the long-term rumen simulation technique (Rusitec); use of soluble food and an inert solid matrix

1979 ◽  
Vol 42 (2) ◽  
pp. 229-245 ◽  
Author(s):  
J. W. Czerkawski ◽  
Grace Breckenridge
Keyword(s):  
Dilution Rate ◽  
Solid Phase ◽  
Compartment Model ◽  
Solid Food ◽  
Solid Matrix ◽  
Fermentation Pattern ◽  
Micro Organisms ◽  
Reaction Vessels

1. The role of soluble nutrients and of the solid matrix in rumen fermentation was investigated in some detail, and experiments designed to explore the possibility of using a balanced soluble diet and an inert solid matrix, are described.2. The use of a balanced soluble substrate as the only source of nutrients in the presence of an inert solid phase in the reaction vessels results in vigorous fermentation but is accompanied by disappearance of protozoa from the effluent.3. In the absence of digestible solid phase, the rate of fermentation and the fermentation pattern depends mainly on the amount and type of nutrients supplied and to a smaller extent on the dilution rate, the variations being greatest at low dilution rates.4. The solid matrix in the form of wood shavings or the residue remaining after prolonged digestion of hay could sequestrate micro-organisms and could be used as solid phase, but the defined mixture of soluble substrates used resulted in somewhat abnormal fermentation compared with fermentation obtained with solid food.5. When the solid food included some hay extract and when the dilution rate was not too great a reduced output of protozoa could be maintained. At high dilution rate the outflow of protozoa was negligible and yet considerable numbers of protozoa were found in the solid matrix and associated liquid.6. A three-compartment model was developed to describe the flow of liquid and microbial matter within the simplified system.

scholarly journals Influence of disodium malate on microbial growth and fermentation in rumen-simulation technique fermenters receiving medium- and high-concentrate diets

2005 ◽  
Vol 93 (4) ◽  
pp. 479-484 ◽  
Author(s):  
J. A. Gómez ◽  
M. L. Tejido ◽  
M. D. Carro
Keyword(s):  
Fatty Acids ◽  
Volatile Fatty Acids ◽  
Simulation Technique ◽  
Barley Straw ◽  
Feed Additive ◽  
Daily Production ◽  
Dairy Animals ◽  
Micro Organisms

Two incubation trials were carried out with the rumen-simulation technique (RUSITEC). In each trial, four vessels received a diet of grass hay and concentrate (600 and 400 g/kg DM, respectively; diet F), and the other four were fed a diet composed of concentrate and barley straw (900 and 100 g/kg DM, respectively; Diet C). Vessels were given 20 g of the corresponding diet daily, and half of them were supplemented with disodium malate to achieve a final concentration of 6.55 mM. There were no effects (P>0·05) of malate either on pH or on the daily production of NH3-N, but malate treatment increased (P<0·05) DM, neutral detergent and acid detergent fibre disappearance after 48 h incubation. The daily production of propionate and butyrate increased (P<0·001), and the ratio CH4:volatile fatty acids decreased (P<0·001) by supplementing both diets with malate. Whereas adding malate to the F diet produced an increase in acetate production (P=0·011) and the growth of solid-associated micro-organisms (P=0·037), no effects (P>0·05) were observed for diet C. For both diets, there were no differences (P>0·05) between treatments in the daily flow of liquid-associated micro-organisms measured using15N as a microbial marker. These results indicate that malate stimulated thein vitrofermentation of both diets by increasing the apparent disappearance of the diet and decreasing the ratio of CH4:volatile fatty acids, but a greater response was observed with diet F. If these results are confirmedin vivo, malate could be used as a feed additive for ruminants fed diets containing medium proportions of forage (i.e. dairy animals) and not only in animals fed high-concentrate diets, as has so far been proposed.

scholarly journals Effect of heating oil on the activity of soil enzymes and the yield of yellow lupine

2011 ◽  
Vol 52 (No. 5) ◽  
pp. 220-226 ◽  
Author(s):  
J. Kucharski ◽  
E. Jastrzębska
Keyword(s):  
Alkaline Phosphatase ◽  
Soil Enzymes ◽  
Urease Activity ◽  
Alkaline Phosphatases ◽  
Acid And Alkaline Phosphatases ◽  
Heating Oil ◽  
Average Activity ◽  
Yellow Lupine ◽  
Experimental Soil ◽  
Limed Soil

The aim of the study was to determine the response of soil enzymes such as dehydrogenases, urease and acid and alkaline phosphatases to heating oil contaminating (0.0, 0.25, 0.5, 0.75, 1.0, 1.5% of soil) the experimental soil supplemented with lime and used for cultivation of yellow lupine of the Markiz variety. An increasing contamination of soil with heating oil stimulated the activity of dehydrogenases and acid and alkaline phosphatases but had a toxic effect on yellow lupine. Lime supplements did not have a significant effect on an average activity of soil dehydrogenases. However, such soil treatment had a significant effect on urease. Increasing heating oil doses in lime-supplemented soil stimulated urease activity, whereas in lime-free soil urease activity was inhibited. The activity of acid and alkaline phosphatase was lower in limed soil than in lime-free soil. The activity of dehydrogenases, urease and alkaline phosphatase in the soil with lupine cultivation was significantly higher than in the unsown soil.

Dietary influence on microbial activities in the caecum of mice

1982 ◽  
Vol 28 (5) ◽  
pp. 493-499 ◽  
Author(s):  
Michelle Brockett ◽  
Gerald W. Tannock
Keyword(s):  
Fatty Acids ◽  
Mouse Strain ◽  
Volatile Fatty Acids ◽  
Urease Activity ◽  
Microbial Production ◽  
Microbial Activities

The nature of the diet (pellets, wheat, breakfast bran) ingested by conventional mice influenced the microbial production of indole, β-glucuronidase, urease, and volatile fatty acids in the caecum. We also observed that the nature of the mouse strain influenced the amount of urease activity present in the caecum.

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.

Effects of black seed oil and Ferula elaeochytris supplementation on ruminal fermentation as tested in vitro with the rumen simulation technique (Rusitec)

2015 ◽  
Vol 55 (6) ◽  
pp. 736 ◽  
Author(s):  
F. Klevenhusen ◽  
K. Deckardt ◽  
Ö. Sizmaz ◽  
S. Wimmer ◽  
A. Muro-Reyes ◽  
...  
Keyword(s):  
Volatile Fatty Acids ◽  
Seed Oil ◽  
Nigella Sativa ◽  
Feed Additives ◽  
Simulation Technique ◽  
Ruminal Fermentation ◽  
Bioactive Components ◽  
Black Seed

Plant bioactive compounds are currently viewed as possible feed additives in terms of methane mitigation and improvement of ruminal fermentation. A range of analyses, including the botanical characterisation, chemical composition and in vitro efficiency, have to be conducted before testing the compounds in vivo. Therefore, the aims of this study were (1) to identify the main bioactive components of black seed (Nigella sativa) oil (BO) and of the root powder of Ferula elaeochytris (FE), and (2) to investigate their effects on ruminal fermentation in vitro, when supplemented in different dosages to a diet (1 : 1, forage : concentrate), using the rumen simulation technique (Rusitec). Main compounds of BO were thymoquinone and p-cymene and α-pinene in FE. Supplementation of the diet with BO and FE did not affect concentration of volatile fatty acids but ammonia concentrations decreased with both supplements (P < 0.001). No effects of supplements on protozoal counts were detected but in vitro disappearance of DM and organic matter tended to increase with 50 mg/L FE (P < 0.1), compared with the control.

scholarly journals Detection of active, potentially acetate-oxidizing syntrophs in an anaerobic digester by flux measurement and formyltetrahydrofolate synthetase (FTHFS) expression profiling

Microbiology ◽  
2011 ◽  
Vol 157 (7) ◽  
pp. 1980-1989 ◽  
Author(s):  
Tomoyuki Hori ◽  
Daisuke Sasaki ◽  
Shin Haruta ◽  
Toru Shigematsu ◽  
Yoshiyuki Ueno ◽  
...  
Keyword(s):  
Volatile Fatty Acids ◽  
Transcriptional Profiling ◽  
Flux Measurement ◽  
Batch Cultivation ◽  
Anaerobic Digester ◽  
High Turnover ◽  
Anaerobic Digesters ◽  
Formyltetrahydrofolate Synthetase ◽  
Syntrophic Oxidation ◽  
Micro Organisms

Syntrophic oxidation of acetate, so-called reversed reductive acetogenesis, is one of the most important degradation steps in anaerobic digesters. However, little is known about the genetic diversity of the micro-organisms involved. Here we investigated the activity and composition of potentially acetate-oxidizing syntrophs using a combinatorial approach of flux measurement and transcriptional profiling of the formyltetrahydrofolate synthetase (FTHFS) gene, an ecological biomarker for reductive acetogenesis. During the operation of a thermophilic anaerobic digester, volatile fatty acids were mostly depleted, suggesting a high turnover rate for dissolved H2, and hydrogenotrophic methanogens were the dominant archaeal members. Batch cultivation of the digester microbiota with 13C-labelled acetate indicated that syntrophic oxidation accounted for 13.1–21.3 % of methane production from acetate. FTHFS genes were transcribed in the absence of carbon monoxide, methoxylated compounds and inorganic electron acceptors other than CO2, which is implicated in the activity of reversed reductive acetogenesis; however, expression itself does not distinguish whether biosynthesis or biodegradation is functioning. The mRNA- and DNA-based terminal RFLP and clone library analyses indicated that, out of nine FTHFS phylotypes detected, the FTHFS genes from the novel phylotypes I–IV in addition to the known syntroph Thermacetogenium phaeum (i.e. phylotype V) were specifically expressed. These transcripts arose from phylogenetically presumed homoacetogens. The results of this study demonstrate that hitherto unidentified phylotypes of homoacetogens are responsible for syntrophic acetate oxidation in an anaerobic digester.

scholarly journals Excretion of purine derivatives by ruminants: recycling of allantoin into the rumen via saliva and its fate in the gut

1990 ◽  
Vol 63 (2) ◽  
pp. 197-205 ◽  
Author(s):  
X. B. Chen ◽  
F. D. DeB. Hovell ◽  
E. R. ØRskov
Keyword(s):  
Fatty Acids ◽  
Uric Acid ◽  
Urinary Excretion ◽  
Volatile Fatty Acids ◽  
Rumen Fluid ◽  
Purine Derivatives ◽  
Complete Destruction ◽  
Series Of Experiments ◽  
Micro Organisms

The saliva of sheep was shown to contain significant concentrations of uric acid (16 (sd) 4.5) μmol/l) and allantoin (120 (sd 16.4) μmol/l), sufficient to recycle purine derivatives equivalent to about 0.10 of the normal urinary excretion. When allantoin was incubated in vitro in rumen fluid, it was degraded at a rate sufficient to ensure complete destruction of recycled allantoin. In a series of experiments in which allantoin was infused into the rumen of sheep fed normally, or into the rumen or abomasum of sheep and the rumen of cattle completely nourished by intragastric infusion of volatile fatty acids and casein, no additional allantoin was recovered in the urine. These losses were probably due to the degradation of allantoin by micro-organisms associated with the digestive tract. It is concluded that all allantoin and uric acid recycled to the rumen via saliva will be similarly degraded. Therefore, the use of urinary excretion of purine derivatives as an estimator of the rumen microbial biomass available to ruminants will need to be corrected for such losses.

Synthesis of macromolecules by intestinal cells incubated with ammonia.

1977 ◽  
Vol 233 (4) ◽  
pp. E341 ◽  
Author(s):  
D C Topping ◽  
W J Visek
Keyword(s):  
Orotic Acid ◽  
Intestinal Tract ◽  
Urease Activity ◽  
Intestinal Content ◽  
Unit Weight ◽  
Intestinal Cells ◽  
Mucosal Cell ◽  
Mucosal Cells ◽  
Intestinal Weight ◽  
In Cells

Mucosal cells isolated from the small intestine of chicks and rats were incubated with concentrations of ammonia normally found in the intestinal tract of mammals and birds. NH4Cl added to the incubation medium increased glucose metabolism in cells from both species. Ammonia stimulated incorporation of precursors into RNA and decarboxylation of orotic acid by cells isolated from chickens, but an increase in incorporation of precursors into DNA was not observed in cells from either species. Cultured embryonic chicken duodena showed increased incorporation of orotate into RNA with NH4Cl added to the medium. Rats immunized against jack bean urease showed lower urease activity per gram of dry intestinal content, lower intestinal weight, lower mucosal cell, and total gut protein and less protein per unit weight of DNA in the mucosal cell fraction. The results are compatible with the conclusion that ammonia PRODUCED IN THE INTESTINE BY BACTERIAL UREASES CAUSES SIGNIFICANT CHANGES IN THE CONTENT OF RNA and protein in intestine cells.

Use of the rumen simulation technique (rusitec) to provide micro-organisms for assessing forage rate-of-fermentationin vitro:effect of solid food input to rusitec

1994 ◽  
Vol 1994 ◽  
pp. 93-93 ◽  
Author(s):  
J H T Barbi ◽  
E Owen ◽  
M K Theodorou
Keyword(s):  
Microbial Activity ◽  
Pressure Transducer ◽  
Previous Experiment ◽  
Simulation Technique ◽  
Particle Sizes ◽  
Cellulolytic Activity ◽  
Micro Organisms ◽  
Kinetics Of ◽  
Food Input

In a previous experiment (Barbi, Owen & Theodorou, 1993) effluent fluid from thein vitrorumen simulation technique (RUSITEC - Czerkawski & Breckenridge, 1977) was used as a source of inoculum when fermenting forage in the Pressure Transducer Technique (PTT - Theodorou, Williams, Brooks, Dhanoa, McAllan & Gill, 1993). The main objective was to replace rumen fistulated animals for assessing the fermentation kinetics of forages. However, low microbial activity in RUSITEC effluent-fluid affected the results, such that fermentation profiles were lower than those in controls inoculated with rumen liquor (Barbiet al,1993).In the present study, in an attempt to increase the microbial cellulolytic activity in the effluent fluid, we altered the particle size and increased the amount of substrate added daily to the RUSITEC vessels. Two particle sizes were examined in an attempt to enhance microbial activity and growth by increasing the availability of colonization surfaces.

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