Carbon precursors of methane synthesis in the rumen of sheep dosed with ionophores

Rates of methane (CH4) production and the sources of carbon (C) for its synthesis were studied in four mature ewes when dosed with a CH4-mitigating ionophore ICI-111075, or monensin, or when untreated. The sheep were given 700 g/day of chaffed lucerne hay in equal portions every hour, before and during experiments in which 14C-labelled NaHCO3–, acetate, propionate, lactate and formate were infused intraruminally over 12 h and the specific radioactivity of C (SR) in each of these substrates was determined. During these infusions, the SR of material in the primary pool (the tracer infusion site) and in secondary metabolites of this material (secondary pools) approached asymptotic or ‘plateau’ values. The rate of infusion of 14CH4 (kBq/day) divided by the plateau SR value (kBq/g C) gave estimates of the rate of irreversible loss of CH4 (g C/day). These calculations indicated that CH4 production rate was reduced by 72% when sheep were dosed with ICI-111075 and by 58% when dosed with monensin. With monensin, the reduction in CH4 production was not associated with hydrogen (H2) accumulation in the rumen headspace gases whereas with ICI-111075, the decrease in CH4 production was associated with marked H2 accumulation in the headspace gases. When plateau SR were attained during the tracer infusions, the percentage ratio, (SR in any secondary pool: SR in the primary pool) gave an estimate of the fraction of C in that secondary pool derived from material of the primary pool. Calculated in this way, the percentage of CH4-C derived from rumen fluid carbon dioxide (CO2) averaged 59% in untreated sheep, and when sheep were dosed with ICI-111075, the corresponding percentage averaged 12%. These findings indicate there are sources of C for rumen CH4 synthesis other than rumen fluid CO2. However, there was no evidence that C from acetate, propionate, lactate or formate in rumen fluid were direct sources of the unidentified CH4-C. One plausible explanation for these findings is that CH4 is synthesised within naturally occurring microbial biofilms (attached to feed particles or the rumen wall) from CO2 that is produced locally by fermentation of unlabelled substrates within the biofilms. It is postulated that such pools of CO2 would be kinetically distinct and, during the infusion of 14C-labelled substrates, would exhibit a lower SR than the CO2 in the surrounding rumen fluid.

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Rapid Mass Spectrometric Study of a Supercritical CO2-extract from Woody Liana Schisandra chinensis by HPLC-SPD-ESI-MS/MS

Molecules ◽

10.3390/molecules25112689 ◽

2020 ◽

Vol 25 (11) ◽

pp. 2689

Author(s):

Mayya Razgonova ◽

Alexander Zakharenko ◽

Konstantin Pikula ◽

Ekaterina Kim ◽

Valery Chernyshev ◽

...

Keyword(s):

Carbon Dioxide ◽

Mass Spectrometric Study ◽

Selective Extraction ◽

Extraction Methods ◽

Schisandra Chinensis ◽

Esi Ms ◽

Naturally Occurring ◽

Target Analytes ◽

Carbon Dioxide Co2 ◽

Rapid Mass

Woody liana Schisandra chinensis contains valuable lignans, which are phenylpropanoids with valuable biological activity. Among green and selective extraction methods, supercritical carbon dioxide (SC-CO2) was shown to be the method of choice for the recovery of these naturally occurring compounds. Carbon dioxide (CO2) was the solvent with the flow rate (10−25 g/min) with 2% ethanol as co-solvent. In this piece of work operative parameters and working conditions were optimized by experimenting with different pressures (200–400 bars) and temperatures (40–60 °C). The extraction time varied from 60 to 120 min. HPLC-SPD-ESI -MS/MS techniques were applied to detect target analytes. Twenty-six different lignans were identified in the S. chinensis SC-CO2 extracts.

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Carbon exchange between the atmosphere and subtropical forested cypress and pine wetlands

Biogeosciences Discussions ◽

10.5194/bgd-11-15753-2014 ◽

2014 ◽

Vol 11 (11) ◽

pp. 15753-15791

Author(s):

W. B. Shoemaker ◽

J. G. Barr ◽

D. B. Botkin ◽

S. L. Graham

Keyword(s):

Carbon Dioxide ◽

Methane Emission ◽

Vegetation Index ◽

Overland Flow ◽

Net Ecosystem Exchange ◽

Forested Wetland ◽

Carbon Dioxide Exchange ◽

Cypress Swamp ◽

Ch4 Production ◽

Carbon Dioxide Co2

Abstract. Carbon dioxide exchange between the atmosphere and forested subtropical wetlands is largely unknown. Here we report a first step in characterizing this atmospheric–ecosystem carbon (C) exchange, for cypress strands and pine forests in the Greater Everglades of Florida as measured with eddy covariance methods at three locations (Cypress Swamp, Dwarf Cypress and Pine Upland) for one year. Links between water and C cycles are examined at these three sites, and methane emission measured only at the Dwarf Cypress site. Each forested wetland showed net C uptake (retained in the soil and biomass or transported laterally via overland flow) from the atmosphere monthly and annually. Net ecosystem exchange (NEE) of carbon dioxide (CO2) (difference between photosynthesis and respiration, with negative values representing net ecosystem uptake) was greatest at the Cypress Swamp (−1000 g C m-2 year-1), moderate at the Pine Upland (−900 g C m-2 year-1), and least at the Dwarf Cypress (−500 g C m-2 year-1). Methane emission was a negligible part of the C (12 g C m-2 year-1) budget when compared to NEE. However, methane (CH4) production was considerable in terms of global warming potential, as about 20 g CH4 emitted per m2 year was equivalent to about 500 g CO2 emitted per m2 year}. Changes in NEE were clearly a function of seasonality in solar insolation, air temperature and water availability from rainfall. We also note that changes in the satellite-derived enhanced-vegetation index (EVI) served as a useful surrogate for changes in net and gross atmospheric–ecosystem C exchange at these forested wetland sites.

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Engineering Pipelines for Transportation of CO2 With Impurities

2010 8th International Pipeline Conference, Volume 2 ◽

10.1115/ipc2010-31651 ◽

2010 ◽

Cited By ~ 2

Author(s):

Gabe Nahas ◽

Mo. Mohitpour

Keyword(s):

Carbon Dioxide ◽

North America ◽

Enhanced Oil Recovery ◽

Oil Recovery ◽

Pipeline Transportation ◽

Naturally Occurring ◽

The Usa ◽

Carbon Dioxide Co2

Pipeline transportation of carbon dioxide (CO2) dates back to the early 1970’s with the construction of the Canyon Reef Carriers & Val Verde pipeline in Texas USA. Since that time about 7200 kilometers of CO2 pipeline have been built in North America (mostly in the USA), some in Asia (Turkey) and Africa and one offshore Europe. The experience of such pipelines is predominantly for the transportation of naturally occurring and relatively pure CO2 for the purpose of enhanced oil recovery (EOR).

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Dynamics of protozoa in the rumen of sheep

British Journal Of Nutrition ◽

10.1079/bjn19820123 ◽

1982 ◽

Vol 48 (2) ◽

pp. 399-415 ◽

Cited By ~ 47

Author(s):

R. A. Leng

Keyword(s):

Protein Synthesis ◽

Sodium Chloride ◽

Half Life ◽

Rumen Fluid ◽

Specific Radioactivity ◽

Microbial Protein ◽

Replacement Rate ◽

Irreversible Loss ◽

Fluid Medium

1. Protozoa were labelled by incubating 100 ml rumen fluid with [14C]choline for 1 h. The protozoa were concentrated by centrifugation and then washed with rumen fluid. This reduced residual14C in the fluid medium to insignificant amounts whilestill retaining the viability of the labelled protozoa. Washing procedures using formal saline (40 g formaldehyde/1 saline (9 g sodium chloride/1)) and saline were developed to isolate protozoa for estimation of specific radioactivity.2. The protozoal pool in freshly-collected rumen fluid incubated in vitro retained 90%of the radioactivity for up to 6 h following addition of14C-I a belled protozoa produced as indicated previously. The specific radioactivity of protozoa did not change during the incubation period.3. Protozoa labelled with [14C]choline and then stored until they died rapidly lost14C to methane when they were incubated in rumen fluid or were injected into the rumen. Some [14C]choline was salvaged under these conditions by the live protozoa present as they apparently incorporated up to 13% of the label from the dead protozoa. However, protozoal debris from the injected solution could also have been present in the isolated protozoa.4. The in vitro results suggested that the protozoal preparations were viable, and that the incorporated choline did not have a turnover in excess of the turnover of nitrogen (i.e. specific radioactivity remained constant with time in vitro) suggesting that the dilution of specific radioactivity of protozoa following mixing of a14C-labelled dose of protozoa represented the rate of irreversible loss and also replacement of protozoa in the rumen.5.14C-labelled protozoa had a half-life in the rumen which was greater than that of rumen fluid and in six animals the protozoal replacement rate was l-4·l mg N/min.6. Losses of14C from labelled protozoa in the rumen in methane or via abomasal digesta were 65 and 35% respectively.7. The results suggest that protozoal growth may be as high as 32% of the total microbial protein synthesis in the rumen but that 65% of the protozoa die and are degraded in the rumen.

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A method for determination of carbon dioxide specific radioactivity and concentration in blood, rumen fluid, and expired air

Analytical Biochemistry ◽

10.1016/0003-2697(82)90052-5 ◽

1982 ◽

Vol 124 (2) ◽

pp. 359-363 ◽

Cited By ~ 5

Author(s):

Richard W. Russell ◽

Jerry W. Young

Keyword(s):

Carbon Dioxide ◽

Rumen Fluid ◽

Specific Radioactivity ◽

Expired Air

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Rumen CO2 species equilibrium might influence performance and be a factor in the pathogenesis of subacute ruminal acidosis

Translational Animal Science ◽

10.1093/tas/txz144 ◽

2019 ◽

Vol 3 (4) ◽

pp. 1081-1098

Author(s):

José A Laporte-Uribe

Keyword(s):

Carbon Dioxide ◽

Surface Tension ◽

Rumen Fluid ◽

Neutral Detergent Fiber ◽

Subacute Ruminal Acidosis ◽

Ruminal Acidosis ◽

Rumen Ph ◽

Carbon Dioxide Co2 ◽

Dietary Treatments

Abstract This experiment was conducted to explore rumen carbon dioxide (CO2) species equilibrium. Three lactating, fistulated cattle were consecutively exposed to three dietary treatments tailored to produce low rumen pH and increase the risk of subacute ruminal acidosis (SARA) by reducing physically effective neutral detergent fiber (Low peNDF), increasing rumen degradable starch (High RDS) or both (Combined). Under these conditions, high and varied rumen concentrations of the CO2 associated to water or dissolved CO2 (dCO2) were found. The results suggest that the activity of dCO2 and bicarbonate (HCO3−) represents an important component of the rumen environment. Rumen CO2 holdup was associated with high dCO2 and HCO3− activity as well as changes in the viscosity and surface tension of the rumen fluid. All dietary treatments produced low rumen pH, <5.5 for >3 h/d, a condition associated with SARA, but clinical SARA was observed only during CO2 holdup. This pilot study highlights the possible role of CO2 holdup and rumen CO2 species in cattle performance and nutritional diseases. In the future, better estimations of CO2 species might help clarify these findings.

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Carbon Dioxide (CO2) Chemosensitivity and SUDEP

Case Medical Research ◽

10.31525/ct1-nct04134754 ◽

2019 ◽

Author(s):

Keyword(s):

Carbon Dioxide ◽

Carbon Dioxide Co2 ◽

Co2 Chemosensitivity

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PERANCANGAN PROTEKSI KEBAKARAN OTOMATIS PADA KAPAL BERBASIS ARDUINO

Jurnal Teknologi Maritim ◽

10.35991/jtm.v1i2.825 ◽

2018 ◽

Vol 1 (2) ◽

pp. 1-8

Author(s):

Dody Hidayat

Keyword(s):

Carbon Dioxide ◽

Fire Extinguisher ◽

Carbon Dioxide Co2

Kebakaran dapat terjadi dimana saja salah satunya dapat terjadi di alat transportasi air yakni kapal. Kebakaran selalu menyebabkan hal-hal yang tidak diinginkan baik kerugian material maupun ancaman keselamatan jiwa manusia. Seiring dari kejadian tersebut musibah kecelakaan kapal yang disebabkan oleh bahaya kebakaran sangatlah mungkin terjadi. Salah satu yang dapat mencegah kejadian kebakaran pada kapal haruslah dapat mendeteksi dini kebakaran tersebut. Untuk mendeteksi dini terjadinya kebakaran dikapal maka dirancanglah sebuah alat proteksi kebakaran otomatisberbasis adruino. Dimana Arduino merupakan board yang memiliki sebuah mikrokontroller sebagai otak kendali sistem. Sistem otomatisasi atau controller tidak akan terlepas dengan apa yang disebut dengan ‘sensor’. Sensor adalah sebuah alat untuk mendeteksi atau mengukut sesuatu yang digunakan untuk mengubah variasi mekanis, magnetis, panas, sinar dan kimia menjadi tegangan dan arus listrik. sistem yang dirancang ini dilengkapi dengan beberapa sensor diantaranya adalah sensor apiUV-Tron R2868, sensor asap MQ-2 dan kemudian sensor suhuDS18B20. Mikrokontroller sebagai pengendali akan merespon input yang berupa sensor tersebut ketika data yang dibaca oleh sensor mendeteksikebakaran diantaranya mendeteksi adanya asap, kemudian api dan suhu. Sebagai output dari sistem berupa racun api (fire extinguisher)dimana kandungan yang ada pada racun api tersebut berupa Dry Chemical Powder dan Carbon Dioxide (CO2) yang fungsinya digunakan untuk memadamkan api serta dilengkapi buzzer sebagai alarm peringatan jika terjadi kebakaran.

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