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J Simal Lozano

Publications and source records attributed to J Simal Lozano.

17 recordsLinked to original sources
PubMed2001

Aliphatic hydrocarbons in birds of prey from Galicia (NW Spain).

Eleven aliphatic hydrocarbons, unresolved over resolved ratio (U/R), carbon preference index (CPI), pristane/C17 ratio, and totals were determined in six classes of tissues (heart, liver, intestine, muscle, lung, and kidney) of 10 buzzards (Buteo buteo), 10 barn owls (Tyto alba), and five tawny owls (Strix aluco) from Galicia (NW Spain). Among individuals detected at quantifiable levels, in general, C18 was found to be the most abundant. Total aliphatic hydrocarbons were detected in 77% tissue samples. Phytane was detected in only three samples: intestine and muscle of two buzzards and lung of one barn owl. Pristane was found in 15% of total samples. Juveniles had higher concentrations than adults in the three species. Females had higher levels than males except for C32 and C36 in barn owl, C24 in tawny owls, and all hydrocarbons (except pristane) in buzzards. The highest concentrations of aliphatic hydrocarbons were detected in birds from La Coruña

Age Factors↗
PubMed2000

Gas chromatographic determination of the fatty-acid content of heat-treated green beans.

A gas chromatographic method that employs flame ionization detection, a DB-Wax capillary column with helium as the carrier gas, and a split-splitless (1:15) injector was used to determine the effects of different heat treatments on the fatty-acid content of whole green beans (Phaseolus vulgaris, L.). A one-step-extraction-methylation method was used to obtain fatty acid methyl esters from raw and steamed, boiled, pressure-cooked, and microwave-cooked green beans. The fatty-acid profile changed slightly, but heat treatment produced an increase in the fatty-acid content.

Chromatography, Gas↗
PubMed2000

Supercritical fluid extraction of polycyclic aromatic hydrocarbons from liver samples and determination by HPLC-FL.

An extraction/clean-up procedure by SFE was developed for isolating PAHs from liver samples for subsequent HPLC-FL determination of ten PAHs in the enriched extract. Recoveries (90-115%) and RSD % (< or =7.7) were satisfactory. When applied to 11 samples of bird of prey (Tyto alba) protected species and classified of special interest, from the Galicia (Northwest to Spain), benzo[ghi]perylene and indeno[1,2,3-cd]pyrene were undetectable; chrysene and benzo[a]pyrene are only detected in one sample; benzo[a]anthracene and benzo[k]fluoranthene are only quantified in one sample and benzo[b]fluoranthene in two samples. The other PAHs, anthracene, fluoranthene and pyrene are present in almost all the samples.

Animals↗
PubMed1999

Determination of benzo[a]pyrene in some Spanish commercial smoked products by HPLC-FL.

In order to investigate the levels of the potently carcinogenic benzo[a]pyrene (BP), 31 samples of smoke foods were analysed. The samples tested included five samples of meal products, three samples of cheese and 22 samples of fish. A liquid chromatographic method was developed using a fluorescence detector. BP was found in 74% of the samples analysed. The levels varied from not detected to 2.46 microg/kg. Only one sample showed a BP level above 1 microg/kg, the maximum level that the EU intends to set for smoked foods.

Animals↗
PubMed1998

Aliphatic hydrocarbons in wolf tissue samples from Galicia (N.W. Spain).

We have investigated the levels of aliphatic hydrocarbons, UCM and CPI in wolves from Galicia (Spain). The n-alkanes distribution was characterized by a predominance of even carbon n-alkanes. Suprarenal and muscle tissues contained more aliphatic hydrocarbons (AHs) than spleen, liver or kidney. The AHs which were detected were found most frequently in adults and males. The mean concentrations of C10, C33, C34, C35 and C36 were the lowest of all compounds quantified (< 1 mg/kg lipid weight) and C12, C14, C16 and C22 were the highest (> 14.2 mg/kg lipid weight). The presence of phytane and UCM (> 3) together to PR/C17 and PH/C18 ratios (both < 1) suggest a large contribution of crude oils.

Alkanes↗
PubMed1998

A simple ultraviolet method for discriminating between polychlorobiphenyls and organochloride pesticides coeluting under gas chromatography with electron-capture detection.

Certain congeners of Aroclor 1260 coelute with o,p'-or p,p'-DDT under gas chromatography with electron-capture detection. We describe a simple ultraviolet irradiation method that allows qualitative and quantitative analyses of mixtures of these organochlorides in complex matrices. Detection limits are 0.20 and 0.22 microgram/kg dry mass for Aroclor 1260 and the two DDTs, respectively. The method is applied to six replicate pork liver samples, for which recoveries ranged from 72 to 90%.

Animals↗
PubMed1997

PCBs and PCTs in wolves (Canis lupus, L) in Galicia (N.W. Spain).

Levels of PCBs and PCTs (the Aroclor1260 and Aroclor5460 congeners, respectively) in viscera of wolves of Galicia (N.W. Spain) were determined by capillary GC with electron-capture detection. Mean PCB levels ranged from 0.13 mg/kg of dry tissue in kidney to 3.70 mg/kg in liver. PCTs were detected only in suprarenal capsule, their mean level being 3.77 mg/kg.

Aging↗
PubMed1997

Comparison of supercritical fluid extraction and conventional liquid-solid extraction for the determination of benzo[a]pyrene in water-soluble smoke.

Extraction of benzo[a]pyrene from 12 samples of water-soluble liquid smokes by means of a conventional liquid-solid extraction method was compared with extraction with a supercritical fluid. Results were satisfactory for both methods, there being no significant differences between the recoveries and precisions obtained for each one. The merits and disadvantages of each extraction method are discussed.

Benzo(a)pyrene↗
PubMed1996

Enrichment of benzo[a]pyrene in smoked food products and determination by high-performance liquid chromatography-fluorescence detection.

We developed a procedure for trace enrichment of benzo[a]pyrene (BP) in extracts of smoked food products, and an HPLC-fluorescence detection (FL) method for determination of BP in the enriched extracts. The procedure consists in extraction/sonication of the lyophilized product in hexane, clean-up of the hexane extract by passage through a Sep-Pak Silica Plus cartridge and, subsequently, by partitioning between hexane and dimethyl sulphoxide, and concentration of the BP using a Sep-Pak C18 Plus cartridge. HPLC-FL and quantification limits were 0.049 microgram/l in acetonitrile (< 0.0067 microgram/kg of smoked food) and 0.089 microgram/l in acetonitrile (< 0.012 microgram/kg), respectively. Recovery (94.1%) and RSD (< 8.65%) were satisfactory. When applied to 15 types of sausage, mean BP content was 0.022 microgram/kg, and all but two samples (both treated with wood smoke) had BP contents below the 0.03 microgram/kg limit imposed in EU legislation for smoking-flavour agents.

Benzo(a)pyrene↗
PubMed1996

Determination of benzo[a]pyrene in lipid-soluble liquid smoke (LSLS) by HPLC-FL.

We developed a method for the determination of low levels of the carcinogen benzo[a]pyrene (BaP) in lipid-soluble liquid smoke (LSLS). The method consists of partitioning the LSLS (2 g) between n-hexane and DMSO, purification of the DMSO extracts on Sep-Pak C18 Plus and then Silica Plus cartridges, and determination of the BaP in the isolated extract by HPLC with fluorescence detection. Detection and quantification limits were 0.049 microgram/l (0.024 microgram/kg of LSLS) and 0.089 microgram/l (0.045 mg/kg), respectively. Recovery (87%) and CV% (< or = 1.5) were satisfactory.

Benzo(a)pyrene↗
PubMed1992

Determination of vitamin C and organic acids in various fruits by HPLC.

Liquid chromatographic methodology for determination of vitamin C and organic acids in different fruits (whortleberry, blackberry, red currant, black currant, raspberry, babaco, feijoa, kiwano, passion fruit, red and yellow tamarillos, medlar, and persimmon) cultivated in Galicia, Spain are developed. Both methods use a C18 column and an RP-18 precolumn for the stationary phase. High-performance-liquid-chromatographic-(HPLC-) grade water is brought to pH 2.2 with sulphuric acid for the mobile phase. The flow rate is 0.4 mL/min, and UV detection is at 254 nm for vitamin C and 214 nm for organic acids. Coefficients of variation of 1.84, 1.20, 1.00, and 2.60% are obtained for the vitamin C, quinic acid, malic acid and citric acid, respectively.

Ascorbic Acid↗
PubMed1991

Simplified method for the determination of organochlorine pesticides in honey.

A method is described for the detection and quantitative determination of organochlorine pesticides in honey. After extraction with hexane, the pesticides were cleaned-up by adsorption chromatography on a Florisil Sep-Pak cartridge and eluted with 15% diethyl ether in hexane. The detection of organochlorine pesticides was performed by capillary gas chromatography with electron-capture detection. The quantification limit obtained for different pesticides ranged from 0.56 to 2.78 micrograms kg-1 and recoveries from fortified honey samples averaged 89.6%.

Chromatography, Gas↗
PubMedDate not supplied

Overall migration and specific migration of bisphenol A diglycidyl ether monomer and m-xylylenediamine hardener from an optimized epoxy-amine formulation into water-based food simulants.

The overall and specific migrations of BADGE n = 0 monomer and m-XDA hardener from a BEPOX LAB 889 (Gairesa internal code), epoxy system cured at room temperature, into three water-based food simulants are studied. Hydrolysis of BADGE n = 0 was observed in all of these simulants, giving more polar products. We thus propose changing the EEC Directives, which at present only legislate for levels of BADGE n = 0 monomer in the simulants, to include the hydrolysis products of BADGE monomers. Another alternative would be to express all the migration levels due to BADGE and its derived products in terms of BADGE itself.

Benzhydryl Compounds↗
PubMedDate not supplied

Sensitive and rapid reversed-phase liquid chromatography-fluorescence method for determining bisphenol A diglycidyl ether in aqueous-based food simulants.

A method has been developed for determination of bisphenol A diglycidyl ether (BADGE) in 3 aqueous-based food simulants: water, 15% (v/v) ethanol, and 3% (w/v) acetic acid. BADGE is extracted with C18 cartridges and the extract is concentrated under a stream of nitrogen. BADGE is quantitated by reversed-phase liquid chromatography with fluorescence detection. Relative precision at 200 micrograms/L was 3.4%, the detection limit of the method was 0.1 micrograms/L, and recoveries of spiking concentrations from 1 to 8 micrograms/L were nearly 100%. Relative standard deviations for the method ranged from 3.5 to 5.9%, depending on the identity of the spiked aqueous-based food simulant.

Acetates↗
PubMedDate not supplied

Determination of biphenyl residues in citrus fruit by derivative infrared spectrophotometry.

A method for determination of biphenyl residues in whole citrus fruit is described. The mascerated fruit was distilled in an acid medium, the distillate was extracted with cyclohexane, and biphenyl was determined in the extract using various measures obtained by first and second derivative infrared (IR) spectrophotometry. Calculations were performed by PE680 and SNGLE programs on data obtained using a Perkin-Elmer Model 3600 data station. The relative precision of the determinations at 70 ppm was 1.8 to 2.0%; the detection limit was 5 ppm in all measurements, and recovery of spiking concentrations of 20 to 80 ppm ranged from 90.2 +/- 5.5% (for the amplitude of the 739 cm-1 peak of the first derivative) to 97.5 +/- 2.0% (for the trough-to-peak difference from the 737 cm-1 minimum to the 743 cm-1 maximum of the second derivative.

Biphenyl Compounds↗
PubMedDate not supplied

Simultaneous determination of organic acids and vitamin C in green beans by liquid chromatography.

A method is described for determining and quantitating organic acids (oxalic, malic, citric, and fumaric) and vitamin C by liquid chromatography with a UV-visible detector that allows simultaneous monitoring at 2 wavelengths. The method was applied to samples of green beans (Phaseolus vulgaris L.). Recoveries were 97.8% for oxalic acid, 98.9% for malic acid, 98.7% for citric acid, 99.2% for fumaric acid, and 98.5% for vitamin C. Method precisions (coefficients of variation) were 1.7% for oxalic acid, 0.8% for malic acid, 0.9% for citric acid, 1.5% for fumaric acid, and 1.2% for vitamin C. Measurement precisions (coefficients of variation) were 1.32% for oxalic acid, 0.33% for malic acid, 0.62% for citric acid, 1.01% for fumaric acid, and 0.39% for vitamin C. Limits of detection were 0.025 mg/mL for oxalic acid, 0.022 mg/mL for malic acid, 0.024 mg/mL for citric acid, 1.0 x 10(-4) mg/mL for fumaric acid, and 2.7 x 10(-4) mg/mL for vitamin C.

Acids↗