scholarly journals METHYL MERCURY IN GREEN MUSCLE (Mytilus viridis L.) FROM FISH MARKET MUARA ANGKE : BEFORE AND AFTER COOKING

2010 ◽  
Vol 9 (1) ◽  
pp. 77-83
Author(s):  
Ermin K. Winarno ◽  
Winarti Andayani ◽  
Agustin Sumartono
Keyword(s):  
Gas Chromatography ◽  
Mercury Concentration ◽  
Methyl Mercury ◽  
Mercury Content ◽  
The Other ◽  
Fish Market ◽  
Cooking Process ◽  
Before And After ◽  
Hcl Solution

The determination of methyl mercury content in green muscle (Mytilus viridis L.) that were taken from Pasar Pelelangan Ikan Muara Angke, Jakarta Bay has been carried out. Sampling was taken in November 2005 and March 2006, the samples were bought from the green muscle sellers. The aim of this research is to know the effect of cooking on the content of methyl mercury in green muscle. Samples were homogenized, weighed and washed with aceton and toluene. After washing, the homogenized material was added with HCl solution, extracted with toluene, then the methyl mercury content in toluene extract was analyzed using gas chromatography. The results of this research showed that methyl mercury concentration in raw and cooked green muscle respectively were 0.803 + 0.019 mg/g and 0.443 + 0.035 mg/g (in November 2005) and 0.096 + 0.014 mg/g and 0.079 + 0.016 mg/g (in March 2006) respectively. The methyl mercury content in raw (in November 2005) was higher than in cooked green muscle as permitted concentration in the sea biota by WHO and FAO, it is 0.5 ppm (mg/g), on the other hand the result of the second sampling in March 2006 showed that methyl mercury content in green muscle was lower than permitted concentration. Cooking process of the green muscle decreased methyl mercury content 44.85% (sampling in November 2005) and 17.71% (sampling in March 2006), because methyl mercury that bonded to protein were distributed to boiling water. Methyl mercury content in green muscle after cooking was still lower than the permitted concentration.   Keywords: methyl mercury, green muscle, Mytilus viridis L., Muara Angke

Rapid Semimicro Method for the Determination of Methyl Mercury in Fish Tissue

1972 ◽  
Vol 55 (3) ◽  
pp. 583-589 ◽  
Author(s):  
J F Uthe ◽  
J Solomon ◽  
B Grift
Keyword(s):  
Gas Chromatography ◽  
Thin Layer ◽  
Methyl Mercury ◽  
Total Mercury ◽  
Aqueous Ethanol ◽  
Fish Tissue ◽  
Mercuric Iodide ◽  
Mercury In Fish ◽  
Layer Chromatography

Abstract A fast semimicro method for the determination of methyl mercury in fish tissue is described. The procedure involves extracting the methyl mercury into toluene as methyl mercuric bromide, partitioning the bromide into aqueous ethanol as a thiosulfate complex, and re-extracting into benzene as methyl mercuric iodide. Methyl mercury is quantitated with gas chromatography. The method is sensitive to 0.01 ppm. Recoveries of added methyl mercury were 99% and the presence of methyl mercury in the final extract was shown by thin layer chromatography and gas chromatography of the thin layer spot. A variety of mercurial compounds do not interfere in the analyses. The amounts of both methyl and total mercury found in a variety of tissues of aquatic animals are compared. The presence of a demethylase in seal is suggested by the findings of high levels of nonmethyl mercury. Additional cleanup by column chromatography on Florisil was necessary with certain samples. The gas chromatographic columns were kept operational by the intermittent injection of 3M potassium iodide. Due to column bleed and resulting detector contamination, the use of the easily cleaned concentric tube electron capture detector is recommended.

Determination of Propylene Glycol in Cosmetics by Gas Chromatography

1967 ◽  
Vol 50 (6) ◽  
pp. 1284-1286
Author(s):  
Frederick C Gross ◽  
John H Jones
Keyword(s):  
Gas Chromatography ◽  
Propylene Glycol ◽  
The Other ◽  
Porapak Q ◽  
Hydrogen Flame ◽  
Flame Detector

Abstract Propylene glycol in cosmetics can be determined by co-distillation in water followed by GC measurement of the distilled propylene glycol on a Porapak Q column and a hydrogen flame detector. The procedure has been successfully applied to a number of commercial samples; 14 of 15 sample recoveries were between 95 and 102%, the other recovery was 92%.

Improved Method for Determination of Chlorophenoxy Acid Residues in Total Diet Samples

1971 ◽  
Vol 54 (4) ◽  
pp. 966-969 ◽  
Author(s):  
George Yip
Keyword(s):  
Gas Chromatography ◽  
Electron Capture ◽  
The Other ◽  
Improved Method ◽  
Total Diet ◽  
Chlorophenoxyacetic Acid ◽  
Isothermal Gas

Abstract Modifications to an earlier procedure for chlorophenoxyacetic acid residues are introduced to provide better recoveries, cleaner samples, and sensitivities down to 0.02 ppm. These changes include (1) extracting with acetonitrile or CHCI3, (2) more effective methylation of the acids, (3) Florisil chromatography to separate PCP from the other herbicides, and (4) isothermal gas chromatography by electron capture or microcoulometric detection. The improved procedure was compared with the previous one, using several total diet composites at fortification levels of 0.01–0.05 ppm. Results showed that usable chromatograms were obtainable only with the improved procedure. Recovery studies were made on all commodity groups except for fats, oils, and shortenings. Microcoulometric results were good. Compounds studied were MCP, 2,4-D, 2,4,5-T, 2,4,5-TP, 2,4-DB, PCP, and 2,3,6-TBA.

The determination of the volume and air space of soil clods

1944 ◽  
Vol 34 (3) ◽  
pp. 123-132 ◽  
Author(s):  
E. W. Russell ◽  
W. Balcerek
Keyword(s):  
Moisture Content ◽  
Farmyard Manure ◽  
The Other ◽  
Available Water ◽  
Air Space ◽  
Before And After ◽  
Hydrocarbon Oil

A method is described for determining the field volume and the air space of a clod of any shape by filling its pores with a hydrocarbon oil, such as paraffin or tetralin, and determining its weight in the oil and in air before and after impregnation. The method appears to work well for clods of any moisture content.This method is shown to give values of these volumes entirely comparable with those given by the other accurate methods described in the literature. Its accuracy for clods of Rothamsted soil, weighing between 20 and 500 g., was probably at least 1 part per thousand, i.e. 0-1%.The method has been applied to the determination of the available water held by a soil and has been used to illustrate the effect of long-continued applications of farmyard manure to a soil in increasing the amount of available water it can hold.

scholarly journals The Determination of Menthol in Tobacco, in Filters and in the Smoke of Mentholated Cigarettes/Untersuchungen über die Verteilung des Menthols auf Tabak, Filter und Rauch von Mentholcigaretten

1972 ◽  
Vol 6 (3) ◽  
Author(s):  
M. Brozinski ◽  
U. Dölberg ◽  
G. Lipp
Keyword(s):  
Gas Chromatography ◽  
Cellulose Acetate ◽  
Steam Distillation ◽  
Internal Standard ◽  
Polypropylene Glycol ◽  
Analytical Results ◽  
Before And After ◽  
Selective Retention ◽  
Different Origin

AbstractA method for the determination of menthol in tobacco, in filters before and after smoking as well as in the smoke of mentholated cigarettes is presented which is based on the combination of steam distillation and liquid-Iiquid partition followed by gas chromatography on polypropylene glycol in the presence of benzylpropionate as an internal standard. The procedure also permits menthone to be quantitatively determined as a characteristic constituent of peppermint oils. Analytical results concerning reproducibility, recovery and sensitivity of the method are detailed. The transfer of menthol from the tobacco rod to the acetate filter and vice versa as a function of the storing period of mentholated cigarettes has been investigated as well as the menthol distribution due to the smoking process. A considerable selective retention of menthol by cellulose acetate filters could be demonstrated. Various mentholated cigarettes of different origin and of different menthol contents have comparatively been analysed.

Determination of the milk yield of sows and correction for loss of weight due to metabolic processes of piglets during suckling

1964 ◽  
Vol 6 (1) ◽  
pp. 119-123 ◽  
Author(s):  
R. L. Van Spaendonck ◽  
F. X. Vanschoubroek
Keyword(s):  
Milk Yield ◽  
The Body ◽  
The Other ◽  
Weight Changes ◽  
Metabolic Processes ◽  
Loss Of Weight ◽  
Before And After ◽  
The One ◽  
The Relationship

SUMMARYIn determining the milk yield of the sow by weighing the litter before and after suckling, loss of weight due to metabolic processes must be considered.An experiment is described to investigate the loss of weight of piglets caused by metabolic processes between two consecutive weighings, and to investigate the relationship between this loss on the one hand and the body weight and the age of the piglets on the other. Weight changes of 15 litters of average 9·8 piglets were studied during 66 weighing periods of 16 minutes, by putting the pigs in a cage, fixed on a differential balance. Each weighing period consisted of 8 periods of 2 minutes, so that in all, loss of weight was studied during 528 2-minute periods.

Selective Determination of Methyl Mercury in Biological Samples by Means of Programmed Temperature Gas Chromatography

1993 ◽  
Vol 76 (3) ◽  
pp. 608-614 ◽  
Author(s):  
R A Lorenzo ◽  
A Carro ◽  
E Rubí ◽  
C Casais ◽  
R Cela
Keyword(s):  
Gas Chromatography ◽  
Biological Samples ◽  
Methyl Mercury ◽  
Chromatographic Method ◽  
Preliminary Treatment ◽  
Selective Determination ◽  
Good Linearity ◽  
Aoac Official ◽  
Gas Chromatographic Method

Abstract A programmed temperature gas chromatographic method is presented by which it is possible to carry out routine analysis of methyl mercury in biological samples prepared according to the AOAC official first action recommendations without the need for preliminary treatment of the columns. This method greatly extends the life of the columns as well as the useful time for analysis; it has good linearity and repeatability. With the proposed method a total of 36 samples can be analyzed daily.

scholarly journals Determination of the Volatile Profile of Lemon Peel Oils as Affected by Rootstock

Foods ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 241 ◽  
Author(s):  
Marlene G. Aguilar-Hernández ◽  
Paola Sánchez-Bravo ◽  
Francisca Hernández ◽  
Ángel A. Carbonell-Barrachina ◽  
Joaquín J. Pastor-Pérez ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
The Other ◽  
Gas Chromatography Mass Spectrometry ◽  
Citrus Limon ◽  
Citrus Aurantium ◽  
Volatile Profile ◽  
The Usa ◽  
Citrus Macrophylla

Citrus limon (L.) Burm is an important crop that grows between latitudes 30° North and 30° South, the main producers being China, the USA, Mexico, India, Brazil, and Spain. In Spain, lemon grows mainly in Mediterranean areas such as Murcia, Valencia, and Andalucía. The most cultivated varieties are “Fino” and “Verna”. In this study, five varieties of lemon, “Verna”, “Bétera”, “Eureka”, “Fino 49”, and “Fino 95” were evaluated on different rootstocks: three new Forner-Alcaide (“FA13”, “FA5”, “FA517”), Citrus macrophylla, Wester, and Citrus aurantium L. Hydrodistillation was used to obtain essential oil from fresh peels and then the volatile profile was studied by gas chromatography-mass spectrometry (GC-MS). A total of 26 volatile compounds were identified, limonene being the main one followed by β-pinene, γ-terpinene, sabinene, and α-pinene. The results revealed that Forner-Alcaide rootstocks (“FA5” > “FA517” > “FA13”) proved to be the best rootstocks for the aroma quality as they led to high volatile contents, followed by C. aurantium and C. macrophylla. Among the other varieties, the most aromatic one was “Eureka”. The whole trend was as follows (in decreasing order): “Eureka” > “Bétera” > “Fino 95” > “Verna” > “Fino 49”.

Release of Methyl Mercury from Sediments: Effects of Mercury Concentration, Low Temperature, and Nutrient Addition

1982 ◽  
Vol 39 (11) ◽  
pp. 1459-1466 ◽  
Author(s):  
David R. Wright ◽  
R. D. Hamilton
Keyword(s):  
Low Temperature ◽  
Water Flow ◽  
Mercury Concentration ◽  
Methyl Mercury ◽  
River Sediments ◽  
Mercury Content ◽  
Mercury Methylation ◽  
Mercury Release ◽  
Saturation Kinetics ◽  
Flow Through

A flow-through system using plexiglass "microbasins" was used to study methyl mercury release from unpolluted, mercury polluted, and mercury enriched lake and river sediments. Production of methyl mercury ranged up to 3.3 μg∙m−2∙d−1, increasing with increasing mercury content as if following saturation kinetics. It leveled off when mercury content was 15–20 μg Hg/g. An equilibrium between methylating and demethylating mechanisms is suggested. Release at 4 °C was 50–70% of that at 20 °C, which suggests that in polluted Canadian lakes, production in winter may be half the total for the year. Increased methyl mercury release was observed when tryptic soy broth (TSB) was added to sediments at 0.06 or 0.25 g/dm3, and very marked increases when TSB was added to the water flow at 35 mg/L, suggesting an effect at the sediment–water interface.Key words: mercury, methyl mercury, methylation, microbasin, microorganism, sediments, biomethylation

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