Column Gas-liquid Chromatography Research Articles

An efficient method for simultaneous detection of Pheniramine, Pentazocine and cotinine in urine by Gas Chromatography in De-addiction program.

Nonmedical use of prescription drugs for recreational purposes is a major health problem that raises high concerns for public health. Recently, several laboratory studies have reported the misuse of pentazocine, an agonist-antagonist opioid in combination with antihistamines in opioid addicts. Illicit self-administration of prescription drugs has been increasingly reported in India. Urinalysis as an adjunct to self-report plays a key role in providing additional information in the treatment of drug users. This paper aims to discuss a simple, convenient, and rapid capillary column gas-liquid chromatography method for simultaneous detection of pentazocine, pheniramine, and cotinine in urine. The sample was extracted with chloroform and isopropanol (3:1,v/v) and evaporated to dryness. After reconstitution with methanol, it was directly subjected to gas chromatography analysis. Method performance was evaluated and validated in terms of sensitivity, precision, the limit of detection (LOD), and the limit of quantification (LOQ). The linearity obtained was in the range of 50-1000 ng/ml with a correlation coefficient (r) above 0.999 for each drug. Good LOQ (50ng/ml) was obtained with each drug. Also, the developed method was effective in analyzing samples from patients with suspected abuse of these drugs. The technique was found to be simple, robust, sensitive, and precise in the simultaneous analysis of drugs (pentazocine, pheniramine, and cotinine). This method was proved to be useful and cost-effective in treating and monitoring patients seeking help for addiction in clinical settings.

Highly Sensitive Simultaneous Measurement of Steroid Hormone in Human Serum by Liquid Chromatography-electrospray Ionization Tandem Mass Spectrometry

Highly Sensitive Simultaneous Measurement of Steroid Hormone in Human Serum by Liquid Chromatography-electrospray Ionization Tandem Mass Spectrometry

Can long chain n-3 fatty acids from feed be converted into very long chain n-3 fatty acids in fillets from farmed rainbow trout (Oncorhynchus mykiss)?

The link between the basic chemical and fatty acid composition of trout feed on one hand and trout (Oncorhynchus mykiss) meat (fillet) was investigated.. The content of 52 fatty acids from feed and trout meat lipids was determined by in-situ transesterification and capillary column gas-liquid chromatography. On average, 100 g of trout feed contained 7.4 g of moisture, 47.7 g of proteins, 6.09 g of ash, 21.4 g of fat, and as for fatty acid composition, 47.8 wt. % were monounsaturated, 34.0 wt. % were polyunsaturated and 18.1 wt. % were saturated fatty acids, with the PS ratio 1.88, n-6/n-3 ratio 1.74, 0.80 wt. % of trans and 3.28 wt. % of very long chain n-3 fatty acids. On average, 100 g of trout meat contained 76.1 g of moisture, 21.4 g of proteins, 1.34 g of ash, 2.52 g of fat, and in the fatty acid composition 42.1 wt. % were monounsaturated, 38.2 wt. % were polyunsaturated and 18.9 wt. % were saturated fatty acids, with the PS ratio 2.02, n-6/n-3 ratio 0.98, 0.95 wt. % of trans and 13.25 wt. % of very long chain n-3 fatty acids.

Chiral analysis of derivatized amino acids from kefir by gas chromatography

The amino acids present in the kefir samples were derivatized using different alkyl chloroformates combined with alcohols and chromatographed on a (3-O-butanoyl-2,6-di-O-pentyl)-γ-cyclodextrin (Lipodex E) chiral gas–liquid chromatographic column. The combination of derivatization reagents that led to better chromatographic performance for standard amino acid solutions was critically compared. All the chloroformate/alchohol mixtures lead to fast and quantitative reactions. However, the ethyl chloroformate/ethanol mixture was selected since the number of enantioseparated amino acid derivatives was higher. The derivatization was applied to samples of kefir grains grown in raw and in skimmed UHT milk. The samples were previously pretreated by elution from a low-pressure ion-exchange columns. Standard addition calibration curves have been used for the quantitative determinations of amino acid derivatives in both samples, and the figs. of merit of the proposed method have been assessed. The l- and d- configuration of d- and l-alanine, d- and l-valine, d-proline, l-threonine, aspartic and glutamic acids, methionine, and cysteine were detected and quantitatively determined.

Chromatographic study of complex formation of adamantane derivatives with β-cyclodextrin

The thermodynamic characteristics for complex formation of molecules of the cage structure with β-cyclodextrin (β-CD) were determined using gas liquid chromatographic columns with glycerol and glycerol + β-CD as with stationary liquid phases assuming equilibrium conditions at infinitely low sorbate concentrations in the gas phase. The influence of the nature and number of substituents in the adamantane fragment on the stability of the formed complexes was shown. Unlike adamantanes, the series of n-decane derivatives shows a decrease in chromatographic retention after addition of β-CD to glycerol indicating the absence of strong interactions of the linear sorbates with β-CD molecules. The parameters were determined for the regression equations relating the values of specific retention volumes to molecular parameters of sorbates such as polarizability, molar volume, liphophilicity, and others. The parameters of the derived equations were used for the determination of the relative contribution of various molecular descriptors to chromatographic retention of the adamantane derivatives on the sorbents studied.

Programming of temperature and flow rate of carrier gas in work with polycapillary columns for gas-liquid chromatography

Methods of programming temperature and flow rate of carrier gas for to reducing the time of analyte separation on polycapillary columns (PCC) are compared. As was shown, the programming of temperature is accompanied by a change of peak shape, associated with the irregular heating of PCC capillaries. The programming of carrier gas flow rate does not distort the shape of chromatography peaks and does not require long time to return the system to the starting conditions.

Henry’s constants and activity coefficients of some organic solutes in 1-butyl,3-methylimidazolium hydrogen sulfate and in 1-methyl,3-trimethylsilylmethylimidazolium chloride

Using a customized capillary gas–liquid chromatography column, Henry’s constants and activity coefficients at infinite dilution are reported for benzene, toluene, ethyl acetate, 1,4-dioxane, 1,2-dimethoxyethane, acetonitrile, nitromethane, tetrahydrofuran, chloroform, methanol, ethanol, and 1-propanol in ionic liquids 1-butyl,3-methylimidazolium hydrogen sulfate [BMIM][HSO4] and 1-methyl,3-trimethylsilylmethylimidazolium [SiMIM][Cl] chloride from 313 to 413K. These acidic ionic liquids may provide suitable media for acid-catalyzed chemical reactions.

Solubilities of some organic solutes in 1-ethyl-3-methylimidazolium acetate. Chromatographic measurements and predictions from COSMO-RS

Infinite-dilution activity coefficients and Henry’s constants for several organic solutes in 1-ethyl-3-methylimidazolium acetate [EMIM][Ac] were measured from T = 313 K to T = 413 K using two types of gas–liquid chromatography columns: packed columns and an open tubular wall-coated (OTWC) column. The organic solutes include n-hexane, 1-hexene, cyclohexane, heptane, benzene, toluene, ethyl acetate, tetrahydrofuran, 1,4-dioxane, acetonitrile, nitromethane, 1,2-methoxyethane, 1-propanol, 2-propanol, t-butanol and t-amyl alcohol. Results using packed columns are in good agreement with those using the OTWC column. However, there is a useful advantage associated with an OTWC column: for solutes such as alcohols, that have strong interactions with the stationary phase, measurements are faster due to their shorter retention time compared to those in packed columns.

Variations in the fatty acid composition and nutritional value of Adriatic sardine (Sardina pilchardus Walb.) through the fishing season

We investigated the chemical composition, in terms of water, protein, ash, total fat and fatty-acid composition, of sardine meat, and estimated its nutritional value. The samples originated from Adriatic sardines (Sardina pilchardus Walb.) that were collected in the north Adriatic Sea through the winter, spring, summer and autumn seasons. The content of 20 fatty acids was determined by in-situ transesterification and capillary column gas-liquid chromatography, using nonadecanoic acid (19:0) as internal standard. The mean contents of the sardine meat were: 70.8% water, 21.0% protein, 2.5% ash and 6.4% fat. For the fatty-acid composition, 18.0% were mono-unsaturated, 42.6% polyunsaturated and 39.8% saturated. The total-fat content increased through the year, from winter to autumn (0.69 to 18.15 g/100 g meat). The fatty-acid composition in the sardine meat varied significantly, with the levels of the polyunsaturated fatty acids (4.6 g/100 g meat), and especially eicosapentaenoic acid (20:5n-3, 0.98 g/100 g meat) and docosahexaenoic acid (22:6n-3, 1.9 g/100 g meat), being the highest in autumn, before spawning. The n-6/n-3 ratio (0.13) and P/S ratio (7.6) show that sardine meat can and should be included in a balanced human diet. Considering the recommended daily intake of n-3 polyunsaturated fatty acids is 0.45 g per day for a healthy population, this would be consumed as 10 g sardine meat collected in the autumn or 100 g sardine meat collected in the winter.

Investigation of the loading capacity of multicapillary chromatographic columns

It was shown by the comparison of multicapillary and single-capillary columns for gas-liquid chromatography that an approximately 100-fold larger sample could be injected into multicapillary columns without substantial loss in efficiency, because the injected sample volume, causing no significant loss in efficiency, is two orders of magnitude higher for gas-liquid multicapillary columns than for gas-adsorption multicapillary columns.

Regional differences of the mouse brain in response to an α-linolenic acid-restricted diet: Neurotrophin content and protein kinase activity

Aims The purpose of this study was to determine a relatively short-term effect of feeding an α-linolenic acid (ALA, n-3)-restricted, linoleic acid (LA, n-6)-adequate diet on neurotrophin contents and protein kinase activities in brain regions of the mouse. Main methods After feeding mice a safflower oil (SAF) diet (ALA-restricted, LA-adequate) or perilla oil (PER) diet (containing adequate amounts of ALA and LA) for 4 weeks from weaning, the fatty acid compositions of brain regions were analyzed by capillary column gas–liquid chromatography, nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) contents were measured using enzyme-linked immunosorbent assay. Key findings The striatum and hippocampus, but not the cerebral cortex, from the SAF group, contained a smaller amount of docosahexaenoic acid (DHA, 22:6n-3) than those from the PER group. The NGF contents in these brain regions were not different between the two dietary groups. However, the striatal BDNF content of the SAF group was significantly lower than that of the PER group. Protein kinase A, protein kinase C, and p44/42 mitogen-activated protein kinase (p44/42 MAPK) activities in brain regions showed no significant difference between the two dietary groups. However, the striatal p38 MAPK activity was significantly lower in the SAF group than in the PER group. No such differences were observed in the hippocampus or the cerebral cortex. Significance A relatively short-term feeding of an α-linolenic acid-restricted, linoleic acid-adequate diet was found to lower the DHA content, BDNF content and p38 MAPK activity in the mouse striatum.

Hypothesis Generating Study Of Simple Carbohydrates In The Amniotic Fluid In Normal And Down Syndrome Pregnancies

Introduction: Disorders of carbohydrate metabolism, in particular galactosemias, may be associated with mental retardation. For this reason, simple carbohydrates were investigated in the amniotic fluid from normal and Down syndrome fetuses. Materials and Methods: Amniotic fluid specimens were obtained from a cytogenetic laboratory. These were archived specimens from prior amniocenteses. Gas-Liquid chromatography/mass spectrometry was used for the assays. Results and Discussion: Gluconic acid was higher in Down syndrome than in normal amniotic fluid (p=0.039). This finding requires confirmation. Gluconate may be seen with therapeutic gluconates such as iron, zinc and calcium gluconate. There was a trend (p = 0.07) toward elevation of dulcitol in the Down syndrome group. Dulcitol, also known as galactitol, is a toxic metabolite seen in galactosemia. This finding may benefit from further investigation with a larger sample size. INTRODUCTION In recent years there has been a growing interest in the biology and biochemistry of simple sugars. These are important in many biological systems and occur either in small molecules as monosaccharides and disaccharides, or in large polymers. In larger molecules, sugars may be combined with proteins to form glycoproteins, or mucopolysaccharides. Carbohydrates contribute part of the extracellular matrix and often may appear as cell surface antigens. Carbohydrates may be importantly involved in the development of the CNS [1]. Diseases affecting carbohydrates may also affect brain development and intelligence. Children who have galactosemia, for example, may have developmental delay, poor growth, speech delay, mental deficiency, and other problems. Other children with mucopolysaccharidoses may also have abnormal brain development [2] As far as the authors are aware, relatively little has been done to investigate carbohydrates in Down syndrome. As part of a broader program to study the biochemistry of fetuses with Down syndrome, carbohydrates were studied from fetuses of normal and Down syndrome pregnancies. The goal was to generate hypotheses relating to carbohydrate metabolism in fetuses with Down syndrome. MATERIALS AND METHODS Amniotic fluid samples from normal and Down syndrome pregnancies were obtained from the Medical College of Virginia Cytogenetic Laboratory, Richmond, Virginia USA, and were then shipped on dry ice over night to the Metabolic Screening Laboratory at Saint Louis University, Saint Louis, Missouri, USA Amniotic fluid was prepared and analyzed as Shoemaker and Elliott (1991) had previously described for urine [3]. Hypothesis Generating Study Of Simple Carbohydrates In The Amniotic Fluid In Normal And Down Syndrome Pregnancies 2 of 4 Amniotic fluid samples were prepared for analysis with a derivatizing agent which insured that all small molecules would be volatile. Samples were then placed in the gasliquid chromatography column for separation prior to subsequent quantization and identification. The amniotic fluid specimens were thus analyzed by gas-liquid chromatography/mass spectrometry. The experimental protocol was submitted to Institutional Review Boards both at Saint Louis University, USA and the Medical College of Virginia, USA. Due to the use of archived specimens, both Review Boards waived further review. Non-parametric analysis in the form of Mann Whitney rank sum test was performed because the data was not normally distributed. SigmaStat® 3.0 was used for the statistical analysis. RESULTS AND DISCUSSION Gluconic acid in Down syndrome (0.375 M/L) was higher than in normals (0.15 M/L) and the difference was statistically significant (p=0.039). This difference should be investigated further for confirmation. Gluconate is a counterion for nutritional supplements (e.g. calcium gluconate or ferrous gluconate). It is unclear why there should be a difference in amniotic fluid specimens between normal and Down syndrome fetuses. This finding could be a spurious result of testing a large group of metabolites. There was a trend (p=0.07) toward higher dulcitol in the Down syndrome group. Previous animal studies indicated that dulcitol has toxic effects related to tissue glycogen metabolism [2]. More recent studies show that dulcitol is a toxic metabolite found in galactosemia, an inborn error of galactose metabolism [4]. While the difference was not statistically significant, the harmful nature of dulcitol suggests further investigation to determine whether it is evelated in Down syndrome amniotic fluid. Figure 1 Table 1: Levels (uM/L) of carbohydrates in normal and Down syndrome amniotic fluid (Mann-Whitney Rank Sum Test) CONCLUSION In summary, the finding with statistical significance was that of elevated gluconic acid in amniotic fluid from fetuses with Down syndrome. There was also a trend toward dulcitol (galactitol) elevation. Both of these findings suggest testable hypotheses for future investigation into the disease mechanisms of Down syndrome.

Comparative analysis of pyrolysis oils and its subfractions under different atmospheric conditions

In this paper comparative analysis of bio-oils and their subfraction from static, sweeping gas and steam pyrolysis of apricot pulp, a food industry waste, was investigated. Experimental studies were conducted in a well-swept fixed-bed reactor with a heating rate of 5 °C min− 1, to a final pyrolysis temperature of 550 °C. The oil yield which was 22.4% at the static atmosphere reached to the value of 23.2% in the sweeping gas atmosphere by using 100 cm3 min− 1 N2 flow rate. The yield of liquid product in steam pyrolysis was higher (27.2%) than the static and inert gas atmosphere.The elemental analyses of the pyrolysis oils were determined, and the chemical compositions of the oils were investigated using chromatographic and spectroscopic techniques. The liquid products were fractionated into pentane solubles and insolubles (asphaltenes). Pentane solubles were then solvent fractionated into pentane, toluene, and methanol subfractions by fractionated column chromatograpy. The aliphatic subfractions of the oils were then analysed by capillary column gas–liquid chromatography and GC/MS. For further structural analysis, the pyrolysis oils' aliphatic, aromatic and polar subfractions were conducted using FTIR and 1H NMR spectra.

Structural Analysis of Pyrolysis Products From Pyrolysis of Hazelnut (Corylus Avellana L.) Bagasse

Fixed-bed pyrolysis biooils of hazelnut (Corylus Avellana L.) bagasse have been identified for their structures. The condensed biooils were analyzed for their properties as fuels and compared with petroleum-derived products. The biooil was analyzed by Fourier Transform infrared spectroscopy (FTIR) and 1H-NMR spectra. The biooils were fractionated into pentane solubles and insolubles. Pentane solubles were then solvent fractionated into pentane, toluene and methanol subfractions by fractionated column chromatograpy. The aliphatic subfractions of the biooils were then analyzed by capillary column gas-liquid chromatography (GC). In addition, the physical properties, higher heating value and elemental analysis of the biooil were determined. The empirical formula of biooil that has a heating value of 34.57 MJ/kg was established as CH1.45O0.33N0.127. Chromatographic and spectroscopic studies on the biooil showed that the oil obtained from hazelnut bagasse could be used as a renewable fuel and chemical feedstock.

Statistical evaluation of an analytical GC/MS method for the determination of long chain fatty acids

In-depth evaluation of an analytical method to detect and quantify long chain fatty acids (C 8–C 16) at trace level concentrations (25–1000 μg/l) is presented. The method requires derivatization of the acids with methanolic boron trifluoride, separation, and detection by gas chromatography–mass spectrometry. The calibration experiments passed all the tested performance criteria such as linearity, homoscedasticity, and ruggedness. The detection limits and related quantities were computed by applying the method detection limit, and the calibration line approximation. The values obtained by applying the latter approach were more reliable and consistent with the actual statistical theory of detection decisions and yielded the following concentrations: C 8, 87.6 μg/l; C 10, 45.2 μg/l; C 11, 39.9 μg/l; C 12, 37.7 μg/l; C 14, 41.4 μg/l and C 16, 40.6 μg/l. Two different gas–liquid chromatographic columns were tested and similar results achieved, which shows the ruggedness of the method.

Milk fatty acid composition of goats grazing on alpine pasture

Interest in goat keeping in Slovenia has been growing recently, particularly in areas of higher altitudes, and on remote mountain and highland pastures. No literature data was found on the chemical composition of goat's milk produced on Alpine pasture. Therefore, the aim of our study was to determine the chemical milk composition of two dairy goat flocks kept at different altitudes, with the emphasis on milk fatty acid profile. The highland flock consisted of goats of the Saanen breed grazing at an altitude of 615–630 m, while the mountain flock consisted of goats of Alpine breed grazing at an altitude of 1060–1075 m. Goat keepers in Slovenia do not like keep more than one breed of goats together. The composition, free fatty acids (FFAs) and fatty acid (FA) profile of goat's milk collected from these two flocks grazing on Alpine pasture were determined. FA composition was determined by in situ transesterification and capillary column gas–liquid chromatography. Significant differences between the flocks were found for all components analysed ( P = 0.0019 for protein, P = 0.0001 for lactose, P = 0.0020 for total solids and P = 0.0010 for FFAs), except in fat content. The relationship between the FFA content and total fat was well described by the equation: FFA (mmol/l) = −0.1127 (%) + 0.4588 fat (%) − 0.0359 fat (%) 2, with R 2 = 0.73 and a S.D. of the error of 0.097 mmol/l, n = 40, for both flocks. The most abundant FAs in the milk of both flocks were C16:0, C18:1, n−9, C14:0 and C10:0. The average content of saturated FAs was 74.52 and 73.05% in milk from the higland and mountain flocks, respectively. Three saturated fatty acids (caprylic (C8:0), capric (C10:0) and lauric acid (C12:0)), were present at significantly higher amounts in milk from the highland flock than in milk from the mountain flock. Monounsaturated FAs represented 20.49 and 22.32% and polyunsaturated FAs 3.73 and 3.24% of the milk from the highland and mountain flocks, respectively. Among the monounsaturated FAs, palmitoleic + palmitelaidic acid (16:1, n − 7) showed a significantly higher concentration in milk from mountain flock than in milk from the highland flock. The content of linolelaidic acid (18:2, n − 6) was significantly higher in comparison to milk from the highland flock. The average quantity (32 mg 100 g −1 milk) of essential α-linolenic acid (18:3, n − 3) was slightly higher in milk of the highland flock than in milk from the mountain flock (26 mg 100 g −1 milk).

Tobacco smoke exposure, wheeze, and atopy.

We investigated the effect of in utero and postnatal environmental tobacco smoke (ETS) exposure on respiratory symptoms and atopy in the first 3 years of life in children at high risk of allergic disease (both parents atopic). Three hundred and sixty-nine children were followed from birth and reviewed at ages 1 and 3 years (respiratory questionnaire, skin testing). Parental smoking questionnaires were administered, and plasma cotinine in cord and peripheral blood (at age 1 year) was measured (capillary column gas-liquid chromatography). Wheezing starting in the first year of life was significantly more common in children of smoking mothers (54.2% vs. 39.5%, P = 0.017), but not wheezing starting after age 1 year (10.8% vs. 10.9%, smoking and nonsmoking mothers, P = 0.99). Detectable cord cotinine was not associated with wheeze. More frequent wheeze in infancy was significantly more common in those with detectable 1-year cotinine (e.g., wheeze without colds, 17.8% vs. 5.6%, P = 0.02; wheeze most days, 6.5% vs. 0%, P = 0.04). ETS exposure was not associated with atopy. In the multivariate regression analysis, maternal smoking during pregnancy and/or in the first year of life remained associated with wheeze in the first year of life (odds ratio, 1.88; 95% confidence interval, 1.14-3.12; P = 0.01). ETS exposure in "high-risk" infants increases the risk of wheezing starting in the first year of life, but not after age 1 year. However, ETS exposure has little or no effect on the development of atopy. Measurement of plasma cotinine was no more useful than tobacco exposure assessment by questionnaire in our cohort.

An influence of cooking on fatty acid composition in three varieties of common beans and in lentil

The fatty acid composition of three raw and cooked freeze-dried common bean varieties (Phaseolus vulgaris), namely Cesnjevec, Semenarna 22 and Cipro, and of the lentil (Lens esculenta), var. Anicia, was determined and the influence of storage on their composition was studied. Analyses of fatty acid composition were conducted by in situ transesterification and capillary column gas-liquid chromatography. In raw milled beans average values of about 16% saturated fatty acids (SAT), 6% monosaturated fatty acids (MUFA) and 78% polyunsaturated fatty acids (PUFA) were found. Somewhat different values of 15% of SAT, 25% MUFA and 60% PUFA were found in lentil. In cooked beans the content of all fatty acids was slightly decreased. In cooked lentil the decrease was almost 50%, but the ratios of SAT, MUFA and PUFA in both cases were practically the same. After two years of storage at 4 °C the fatty acid content in raw milled beans was unchanged, but altered in cooked ones. The amounts of linoleic (18:2, n-6) and α-linolenic (18:3, n-3) acid decreased, but myristic (14:0), margaric (17:0) and arachidic (20:0) acids increased. It was found that freeze-dried cooked beans, prepared from raw seed beans, kept 2.5 years at 10 °C, have practically the same fatty acid composition as freeze-dried cooked beans 0.5 year after harvesting.

A 50% n-octylmethyl, 50% diphenyl-polysiloxane as stationary phase with unique selectivity for gas chromatography.

An n-octylmethyl, diphenyl-polysiloxane called SOP-50-Octyl was prepared by a condensation reaction of bis(dimethylamino) n-octylmethylsilane with diphenylsilanediol. The resulting copolymer was a gum with high molecular weight and was obtained with a yield of 80%. 1H and 29Si NMR spectroscopy revealed that the copolymer was a 52% octylmethyl, 48% diphenyl-polysiloxane with random microstructure. Small cyclic impurities could be almost quantitatively removed via a purification step. SOP-50-Octyl was used as stationary phase for the preparation of wall coated open tubular fused silica capillary columns for gas-liquid chromatography. The capillary columns exhibited high separation efficiency and high inertness. The stationary phase offered a unique selectivity due to its unique composition. The Rohrschneider-McReynolds constants indicated a low overall polarity in spite of the high phenyl content, as the polarity was distinctly decreased by the octyl substituent. Furthermore, the octyl substituent was responsible for a high column bleed, reducing the maximum allowable operating temperature to 280 degrees C. The elution temperatures of apolar compounds were increased due to increased interaction of the octyl substituent with the analytes. Some applications with volatile and semi-volatile organic compounds illustrate that SOP-50-Octyl is an excellent choice for confirmational analyses.

The Phytosterol Content of Some Cereal Foods Commonly Consumed in Sweden and in the Netherlands

The aim of this report was to quantify five specific dietary phytosterols and phytostanols (campesterol, β-sitosterol, stigmasterol, β-sitostanol, and campestanol) in cereal foods and to study the effect of boiling on sterol content. A capillary column gas liquid chromatography procedure was used to analyse 76 cereal food items of Swedish and Dutch origin: 19 various flours, grains and germs, 31 processed cereals, including bran, flakes, cereal grains and pasta, nine breads, and 17 biscuits, cakes, crackers, cookies and sweet breads. The median total phytosterol concentration was 49 (range 4.1–344) mg/100 g edible portion (e.p.). Flours, grains and germs had a median concentration of 52 (17–344) mg/100 g e.p., which was similar to breads, 54 (29–89) mg/100 g e.p., and different types of miscellaneous cakes and cookies, 52 (27–112) mg/100 g e.p. Processed cereal products had slightly lower concentrations with a median value of 39 (4.1–200) mg/100 g e.p. In general, β-sitosterol was the dominant phytosterol (62% of the total concentration), followed by campesterol (21%), while there were only small amounts of stigmasterol (4%), β-sitostanol (4%) and campestanol (2%). Boiling of cereal products only influenced the phytosterol concentration through change of water content.