PSVII-17 Use of a dimethyl carbonate extraction for rumen fluid volatile fatty acid quantification by gas chromatograph mass spectrometry

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 451-452
Author(s):  
Andrew P Foote
Keyword(s):  
Volatile Fatty Acids ◽  
Dimethyl Carbonate ◽  
Rumen Fluid ◽  
Internal Standard ◽  
Extraction Process ◽  
Organic Layer ◽  
Gas Chromatograph ◽  
Microcentrifuge Tube ◽  
Wheat Pasture ◽  
Gas Chromatograph Mass Spectrometry

Abstract Analysis of rumen fluid volatile fatty acids (VFA) is typically conducted by injecting acidified aqueous rumen fluid into a gas chromatograph (GC) with a flame ignition detector (FID). Water in GC samples can lead to poor peak shape and to contamination of inlets, potentially causing sample carryover. Aqueous methods are not well suited for use in mass spectrometer (MS) detector systems. The objective of this project was to validate a dimethyl carbonate (DMC) extraction process and GCMS method for rumen VFA analysis. To perform the extraction, 100 µL of sample, KHSO4 (50 g/L), and 2-ethylbutyrate (internal standard; 0.86 mM) are added to a microcentrifuge tube (in order) followed by 1 mL of DMC. The mixture is thoroughly vortexed and centrifuged. The organic layer (top) is removed and placed in a GC vial. The DMC extract is injected (0.5 µL) into an Agilent 5977B GCMS (8:1 split injection) with a polar DB-FFAP column. The column was held at 105°C for 5 min, increased at 10°C/min to 150°C, then 65°C/min to 240°C, and held constant for 10 min. The assay is linear for acetate from approximately 2 mM to at least 130 mM and covers the expected values of rumen concentrations for the other VFA. Recovery of VFA from spiked rumen fluid was tested at three concentrations in rumen fluid from steers fed a finishing diet or grazing wheat pasture. Recovery was not affected by the diet of the animals (P > 0.19) or the amount of VFA spiked (P > 0.27) and averaged 99.9% for all VFA, with valerate being the lowest (95.9%). Including the 10 min hold at 240°C at the end of each run prevented carryover from sample to sample. This method appears to perform well in a GCMS system and accurately and precisely quantify rumen fluid VFA.

C18 Extraction of Atrazine from Small Water Sample Volumes

1992 ◽  
Vol 75 (3) ◽  
pp. 581-583 ◽  
Author(s):  
Timothy R Shepherd ◽  
James D Carr ◽  
Diana Duncan ◽  
Darryll T Pederson
Keyword(s):  
Detection Limit ◽  
Solid Phase ◽  
Internal Standard ◽  
Correlation Coefficients ◽  
Extraction Process ◽  
Sample Volume ◽  
Phase Extraction ◽  
Process Variables ◽  
Gas Chromatograph ◽  
Small Water

Abstract A method was developed to detect atrazine at a 0.05 ppb detection limit with a 10 ml_ sample volume. The herbicide Is extracted from 10 mL water with C18 solid-phase extraction and eluted into a reduction vessel with ethyl acetate. The sample is then evaporated to dryness under a stream of nitrogen and redlssolved for Injection Into a gas chromatograph/ mass spectrometer. Terbuthylazlne is used as Internal standard to compensate for extraction process variables. Standard curves have consistently shown correlation coefficients of 0.99 or better. Duplicate samples show a variance of 5% or less. Twelve samples can be extracted In about 1.5 h with <10 mL organic solvent and minimum glassware.

Study on the precision of the activated charcoal solvent desorption procedure - Correlation of desorption efficiencies

1981 ◽  
Vol 46 (6) ◽  
pp. 1332-1347 ◽  
Author(s):  
Martin Koval
Keyword(s):  
Activated Charcoal ◽  
Carbon Disulphide ◽  
Internal Standard ◽  
Standard Addition ◽  
Published Data ◽  
Single Factor ◽  
Gas Chromatograph ◽  
Model Compounds ◽  
Single Factor Analysis ◽  
Acceptable Agreement

The described method uses activated charcoal sampling tubes for air sampling. Adsorbed compounds are eluted by the static desorption procedure with 1 ml of carbon disulphide, 0.5 ml of the supernatant is filtered off and, after internal standard addition, analysed on a gas chromatograph. Using synthetic calibration mixtures of model organic compounds with air, cumulative sampling and desorption efficiencies for 24 substances were determined for concentration ranges and sample volumes according to current Czechoslovak hygienic standards. Experimental results were treated with the single factor analysis of variance and the precision of the described procedure was estimated for the studied model compounds on the basis of residual sums of squares. Calculated values of cumulative sampling and desorption efficiencies and their precisions were compared with available published data and an acceptable agreement was found. In addition to that, cumulative sampling and desorption efficiencies were also found to be significantly correlated to molar volumes and other related molecular properties for some types of compounds.

scholarly journals Identification of the Potential Role of the Rumen Microbiome in Milk Protein and Fat Synthesis in Dairy Cows Using Metagenomic Sequencing

Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1247
Author(s):  
Xin Wu ◽  
Shuai Huang ◽  
Jinfeng Huang ◽  
Peng Peng ◽  
Yanan Liu ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Amino Acid ◽  
Milk Fat ◽  
Milk Protein ◽  
Volatile Fatty Acids ◽  
Rumen Fluid ◽  
Abundant Species ◽  
Metagenomic Sequencing ◽  
Amino Acid Synthesis ◽  
Prevotella Species

The rumen contains abundant microorganisms that aid in the digestion of lignocellulosic feed and are associated with host phenotype traits. Cows with extremely high milk protein and fat percentages (HPF; n = 3) and low milk protein and fat percentages (LPF; n = 3) were selected from 4000 lactating Holstein cows under the same nutritional and management conditions. We found that the total concentration of volatile fatty acids, acetate, butyrate, and propionate in the rumen fluid was significantly higher in the HPF group than in the LPF group. Moreover, we identified 38 most abundant species displaying differential richness between the two groups, in which Prevotella accounted for 68.8% of the species, with the highest abundance in the HPF group. Functional annotation based on the Kyoto Encyclopedia of Gene and Genome (KEGG), evolutionary genealogy of genes: Non-supervised Orthologous Groups (eggNOG), and Carbohydrate-Active enzymes (CAZy) databases showed that the significantly more abundant species in the HPF group are enriched in carbohydrate, amino acid, pyruvate, insulin, and lipid metabolism and transportation. Furthermore, Spearman’s rank correlation analysis revealed that specific microbial taxa (mainly the Prevotella species and Neocallimastix californiae) are positively correlated with total volatile fatty acids (VFA). Collectively, we found that the HPF group was enriched with several Prevotella species related to the total VFA, acetate, and amino acid synthesis. Thereby, these fulfilled the host’s needs for energy, fat, and rumen microbial protein, which can be used for increased biosynthesis of milk fat and milk protein. Our findings provide novel information for elucidation of the regulatory mechanism of the rumen in the formation of milk composition.

PRELIMINARY EVALUATION OF THE ADDITION OF GLUCOGENIC MATERIALS TO THE RATIONS OF LACTATING COWS

1971 ◽  
Vol 51 (3) ◽  
pp. 721-727 ◽  
Author(s):  
L. J. FISHER ◽  
J. D. ERFLE ◽  
F. D. SAUER
Keyword(s):  
Fatty Acids ◽  
Propylene Glycol ◽  
Milk Fat ◽  
Volatile Fatty Acids ◽  
Rumen Fluid ◽  
Preliminary Evaluation ◽  
Early Lactation ◽  
Lactating Cows ◽  
Ad Libitum ◽  
Beta Hydroxybutyrate

Glutamate, succinate, propylene glycol, or glycerol were added to a basic concentrate at 3.3% of air-dry feed. Each concentrate was fed both ad libitum and in restricted amounts to four cows in early lactation. Dietary intake, milk yield and composition, molar proportions of rumen volatile fatty acids and blood glucose, ketones and plasma free fatty acids were used as criteria of effect of these supplements. Propylene glycol in the diet resulted in a lower intake of concentrate compared with glycerol (11.44 versus 14.30 kg/day) and significantly decreased (P < 0.05) rumen butyrate and plasma beta-hydroxybutyrate. Glutamate supplementation prevented the fall in milk fat content which occurred when the other three supplemented concentrates were fed ad libitum, and this effect may have been related to the constancy in the ratio of acetate to propionate in the rumen fluid.

scholarly journals Quantitative Determination of Azithromycin in Human Plasma by Liquid Chromatography–Mass Spectrometry and its Application in Pharmackokinetic Study

2012 ◽  
Vol 11 (1) ◽  
pp. 55-63 ◽  
Author(s):  
Maizbha Uddin Ahmed ◽  
Mohammad Safiqul Islam ◽  
Tasmin Ara Sultana ◽  
AGM Mostofa ◽  
Muhammad Shahdaat Bin Sayeed ◽  
...  
Keyword(s):  
Mobile Phase ◽  
Solid Phase ◽  
Internal Standard ◽  
Extraction Process ◽  
Serum Samples ◽  
Limit Of Quantification ◽  
Relative Standard ◽  
Linear Concentration Range ◽  
Linear Concentration

Azithromycin is an effective and well-known antimicrobial agent. In the present study, a simple, sensitive and specific LC/MS/MS method has been developed and validated for the quantification of Azithromycin in  human serum samples using Clarithromycin as internal standard. Azithromycin was extracted from biological matrix  by using solid phase extraction process. The chromatographic separation was performed on Luna C18 (3 ?, 2x150   mm) column with a mobile phase consisting of 35 mM ammonium acetate buffer (mobile phase-A) and acetonitrile  and methanol in ratio of 90:10 ( as mobile phase-B) at a flow rate of 0.25 mL/min. The method was validated over a  linear concentration range of 0.5?50.0 ng/mL and limit of quantification (LOQ) was 0.5 ng/mL with a coefficient of  correlation (r2) = 0.9998. The intra-day and inter-day precision expressed as relative standard deviation were 1.64% – 8.43% and 2.32% – 9.92%, respectively. The average recovery of azithromycin from serum was 98.11%. The method  was successfully applied to a pharmacokinetic study after oral administration of Azithromycin 200 mg/5 ml suspension in healthy Bangladeshi volunteers. DOI: http://dx.doi.org/10.3329/dujps.v11i1.12488 Dhaka Univ. J. Pharm. Sci. 11(1): 55-63, 2012 (June)

scholarly journals Variations of Alkaloid Accumulation and Gene Transcription in Nicotiana tabacum

Biomolecules ◽  
2018 ◽  
Vol 8 (4) ◽  
pp. 114 ◽  
Author(s):  
Bo Sun ◽  
Yu-Xiao Tian ◽  
Fen Zhang ◽  
Qing Chen ◽  
Yong Zhang ◽  
...  
Keyword(s):  
Nicotiana Tabacum ◽  
Developmental Stages ◽  
Genetic Effect ◽  
Biosynthetic Gene ◽  
Alkaloid Biosynthesis ◽  
Gas Chromatograph ◽  
Predominant Role ◽  
Whole Plant ◽  
Gene Transcripts ◽  
Gas Chromatograph Mass Spectrometry

To increase the understanding of alkaloid biosynthesis in Nicotiana tabacum during whole plant growth periods, variations of the contents of alkaloids and the transcription of key biosynthetic genes in fresh leaves were investigated in three varieties at five developmental stages. Six alkaloids were analyzed by gas chromatograph–mass spectrometry (GC–MS) and the most abundant alkaloid was observed during the upper leaves maturing stage in the varieties, among which the alkaloid content of K326 was the highest. Considering the genetic effect, variance analysis indicated that the developmental stage played a predominant role in alkaloid accumulation. Moreover, the levels of biosynthetic gene transcripts in the leaves at the vigorous growing stage might contribute to the contents of alkaloids in the leaves during the maturing stages. To further illuminate the metabolism of alkaloid biosynthesis, a correlation among alkaloids was also documented.

Isolation and identification of rumen bacteria capable of anaerobic rutin degradation

1969 ◽  
Vol 15 (12) ◽  
pp. 1365-1371 ◽  
Author(s):  
K. -J. Cheng ◽  
G. A. Jones ◽  
F. J. Simpson ◽  
M. P. Bryant
Keyword(s):  
Volatile Fatty Acids ◽  
Rumen Fluid ◽  
Anaerobic Bacteria ◽  
Heterocyclic Ring ◽  
Ring Structure ◽  
Water Soluble ◽  
Rumen Bacteria ◽  
Isolation And Identification ◽  
Pure Cultures ◽  
Rutin Degradation

Fifteen strains of bacteria capable of degrading rutin anaerobically were isolated from bovine rumen contents and identified by morphological and biochemical evidence as strains of Butyrivibrio sp. Three cultures from a laboratory collection of 53 strains of rumen bacteria also used rutin anaerobically. Two, Butyrivibrio fibrisolvens D1 and Selenomonas ruminantium GA192, cleaved the glycosidic bond of rutin and fermented the sugar but did not degrade the insoluble aglycone produced; the third strain, Peptostreptococcus sp. B178, degraded the substrate to soluble products. Butyrivibrio sp. C3 degraded rutin, quercitrin, and naringin to water-soluble products, showing that the organism cleaved the heterocyclic ring of these compounds. Butyrivibrio sp. C3 fermented the sugar moiety of hesperidin but did not cleave the heterocyclic ring. It did not attack quercetin, taxifolin, protocatechuic acid, or phloroglucinol. In a medium containing rumen fluid, Butyrivibrio sp. C3 degraded rutin more than twice as fast as it did in a medium containing enzymatic casein hydrolyzate, volatile fatty acids, yeast extract, and hemin in place of rumen fluid.The observations reported in this paper are believed to represent the first recorded demonstration of degradation of the heterocyclic ring structure of rutin and other bioflavonoids in pure cultures of anaerobic bacteria.

scholarly journals Concentrate containing calcium salts of fatty acids rich in polyunsaturated fatty acids can change rumen fermentation in grazing goats

2018 ◽  
Vol 39 (6) ◽  
pp. 2621
Author(s):  
Ludmila Couto Gomes ◽  
Claudete Regina Alcalde ◽  
Julio Cesar Damasceno ◽  
Luiz Paulo Rigolon ◽  
Ana Paula Silva Possamai ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Volatile Fatty Acids ◽  
Rumen Fluid ◽  
Latin Square ◽  
Rumen Fermentation ◽  
Ruminal Fermentation ◽  
Calcium Salts ◽  
Linear Effect ◽  
Concentrate Supplementation ◽  
Ruminal Ph

Feeding goats with calcium salts of fatty acids (CSFA) can supply ruminants with lipids, with minimal effects on ruminal fermentation and fiber digestibility. However, there is a shortage of information on the effect of CSFA on characteristics of rumen fermentation in grassland goats. Thus, the present study aimed to assess the addition of CSFA to concentrate on the parameters of rumen fermentation of grazing goats. Five rumen cannulated goats were distributed in a Latin square 5x5 design (treatments: 0%, 1.5%, 3.0%, 4.5% and 6.0% CSFA. The pH, ammonia N and volatile fatty acids (VFA) content were analyzed in the ruminal fluid at 0, 2, 4, 6 and 8 hours after concentrate supplementation. The pH and ammonia N concentration showed a linear effect with the addition of CSFA. There was no effect observed for the VFA molar concentration after grazing goats were fed with the experimental diet. In conclusion, further research is needed to investigate the addition of CSFA to goat diets because there is evidence that CSFA increases ruminal pH and decreases excess ruminal ammonia without changing the VFA concentration in the rumen fluid.

Sign in / Sign up

Export Citation Format

Share Document