Determination of Monensin in Raw Material, Premix, and Animal Feeds by Liquid Chromatography with Correlation to Microbiological Assay

1992 ◽  
Vol 75 (2) ◽  
pp. 272-279 ◽  
Author(s):  
J Matthew Rodewald ◽  
John W Moran ◽  
Alvin L Donoho ◽  
Mark R Coleman
Keyword(s):  
Liquid Chromatography ◽  
Chemical Composition ◽  
Microbiological Assay ◽  
Raw Material ◽  
Individual Factors ◽  
Reference Standard ◽  
Microbiological Activity ◽  
Acidic Conditions ◽  
The Individual

Abstract A method Is described for the detection and quantitation of monensin In raw material, premix, and feeds by liquid chromatography (LC) with postcolumn derlvatlzatlon with vanillin. Monensin was mixed with vanillin under acidic conditions and heated, and the resulting products were measured by a variable wavelength visible detector operating at 520 nm. The LC response of monensin and monensln-llke factors was determined and correlated to the microbiological response of each factor as determined with Streptococcus faeclum. Monensin reference standard was characterized In the same manner as the individual factors. The chemical composition of the reference standard and the relative microbiological potency values were used In combination to calculate the biopotency contribution of each of the monensin factors. A formula was used to transform chemical composition values of the reference standard to total microbiological activity as obtained directly from a microbiological assay. The formula was tested by comparing samples assayed by LC using the formula to report microbiological potency with samples assayed by the Autoturb method. Finally, the LC method was validated with raw material, premix, cattle rations (including liquid supplements), and poultry rations.

Determination of Narasin in Raw Material, Premix, and Animal Feeds by Liquid Chromatography and Correlation to Microbiological Assay

1994 ◽  
Vol 77 (4) ◽  
pp. 821-828 ◽  
Author(s):  
John M Rodewald ◽  
John W Moran ◽  
Alwin L Donoho ◽  
Mark R Coleman
Keyword(s):  
Liquid Chromatography ◽  
Chemical Composition ◽  
Microbiological Assay ◽  
Raw Material ◽  
Reference Standard ◽  
Wavelength Detector ◽  
Acidic Conditions ◽  
The Individual ◽  
Postcolumn Derivatization

Abstract A method is described for the detection and quantitation of narasin in raw material, premix, and feeds by liquid chromatography (LC) and postcolumn derivatization (PCD) with vanillin. Narasin was mixed with vanillin under acidic conditions and heated, and the resulting products were measured by a variable-wavelength detector operating at 520 nm. The LC responses of narasin and narasinlike factors were determined and correlated to the microbiological response of each factor as determined with Streptococcus faecium. Narasin reference standard was characterized in the same manner as the individual factors. The chemical composition of the reference standard (i.e., the amounts of narasin factors expressed in percent) combined with the relative microbiological potency value was used to calculate the biopotency contribution of each narasin factor. A formula was used to transform chemical composition values (amounts of narasin factors expressed in percent) of the reference standard to total microbiological activity as directly obtained from the microbiological assay. The LC method was validated by analyses of raw material, premix, and cattle and poultry rations.

Determination of Monensin in Chicken Tissues by Liquid Chromatography with Postcolumn Derivatization

1994 ◽  
Vol 77 (4) ◽  
pp. 885-890 ◽  
Author(s):  
John W Moran ◽  
J Matthew Rodewald ◽  
Alvin L Donoho ◽  
Mark R Coleman
Keyword(s):  
Liquid Chromatography ◽  
Silica Gel ◽  
Chicken Tissues ◽  
Chicken Muscle ◽  
Limit Of Quantitation ◽  
Microbiological Techniques ◽  
Wavelength Detector ◽  
Acidic Conditions ◽  
Postcolumn Derivatization

Abstract A method is described for the detection and quantitation of monensin in chicken tissues by liquid chromatography with postcolumn derivatization with vanillin. Monensin is extracted from the tissues by homogenization with methanol–water and is isolated and concentrated by liquid–liquid partition and sorbent extraction with silica gel. Monensin is mixed postcolumn with vanillin under acidic conditions and heated, and the resulting products are measured by a variable-wavelength detector operating at 520 nm. The method has a limit of quantitation of 0.025 μg/g and is validated for use in the analyses of chicken muscle, liver, and skin (with adhering fat tissues) for monensin. Standard recoveries from the 3 tissue types tested at 3 levels ranged from 82 to 96%. The method represents an improvement in specificity, accuracy, and analysis time over existing methods, which use microbiological techniques.

A method for the quantitative determination of individual free fatty acids in milk by ion exchange resin adsorption and gas-liquid chromatography

1983 ◽  
Vol 50 (3) ◽  
pp. 321-329 ◽  
Author(s):  
Eric C. Needs ◽  
Graeme D. Ford ◽  
A. Jane Owen ◽  
Brian Tuckley ◽  
Malcolm Anderson
Keyword(s):  
Fatty Acids ◽  
Liquid Chromatography ◽  
Free Fatty Acids ◽  
Exchange Resin ◽  
Ion Exchange Resin ◽  
Gas Liquid Chromatography ◽  
Internal Standards ◽  
Resin Adsorption ◽  
The Individual

SummaryA quantitative method for rapid routine analysis of individual free fatty acids (FFA) in milk was developed. Lipid was extracted from milk in ether and FFA were recovered by shaking the extract with anion exchange resin Amberlyst 26. The resin-bound FFA were methylated directly and the individual acids quantified, using internal standards, by gas-liquid chromatography. The properties of the resin were measured. The validity of the method was established by extraction of FFA mixtures and milk. Individual acids were, on average, found to be within 6% of the actual concentration present in the mixture. An average coefficient of variation of 4·3% was achieved for the major individual fatty acids on repeated extraction of a single milk sample.

scholarly journals DETERMINATION OF PEAT ASH FUSIBILITY OF KIROV REGION DEPOSITS

2019 ◽  
Vol 20 (11-12) ◽  
pp. 27-33
Author(s):  
V. A. Kuzmin ◽  
I. A. Zagrai ◽  
I. A. Desiatkov
Keyword(s):  
Fly Ash ◽  
Chemical Composition ◽  
Melting Temperature ◽  
Operating Temperature ◽  
Melting Characteristics ◽  
Steam Boilers ◽  
Ash Fusibility ◽  
The Individual ◽  
Individual Particles

The paper deals with the issues related to the effect of slagging within the steam boilers furnaces and shows the determination results on peat ash fusibility of Kirov region deposits. Fusibility properties of peat ash (temperatures of deformation, sphere, hemisphere and flow) from the four industrial areas (Dymny, Pishchalsky, Karinsky, Gorokhovsky) depending on its chemical composition are presented. Melting temperature of the mineral part of the peat, determined by GOST, is averaged and does not reflect the actual melting temperature of the individual particles in fly ash. The existence of such separate particles having a melting temperature below the average melting temperature of the ash makes it difficult to find the operating temperature of the torch to reach the minimum of the furnace slagging during peat combustion. The comparison of melting characteristics of peat ash with the reference literature data is performed. The initial slagging temperature is calculated depending on the ratio of the acidic and basic oxides in peat ash.

Identification of an Interfering Substrate in Apple Juice and Improvement for Determination of Patulin with High-Performance Liquid Chromatography Analyses

2009 ◽  
Vol 72 (4) ◽  
pp. 805-809 ◽  
Author(s):  
NAOKI MOCHIZUKI ◽  
MARIKO HOSHINO ◽  
KEIKO SUGA ◽  
YOSHIKO SUGITA-KONISHI
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Apple Juice ◽  
Chemical Properties ◽  
Proton Nuclear Magnetic Resonance ◽  
Official Method ◽  
Improved Method ◽  
Acidic Conditions

An interfering substance that is not 5-hydroxymethylfurfural appears in some apple juices during high-performance liquid chromatography (HPLC) analysis of patulin based on the AOAC 995.10 method. Because this interfering substance could cause the overestimation of patulin in the apple juices, we tried to identify the substance and to develop an improved method of analyzing patulin free from the influence of this substance. We isolated the substance from the apple juice and identified it as adenosine based on its mass spectrometry, proton nuclear magnetic resonance, and photo diode array spectra. Because of the chemical properties of adenosine, changes in the extraction method under acidic conditions and the HPLC conditions (wavelength and analytical column) were effective for avoiding the influence of adenosine and more specifically for analyzing the patulin. The most effective and simple improvement of the official method was the use of column in-point carbon contents greater than 15.5%.

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