جستجوی مقالات مرتبط با کلیدواژه « Gas Chromatography » در نشریات گروه « پزشکی »

Tea (Camellia sinensis), belongs to the family Theaceae, is a well-known perennial and evergreen plant that is processed and widely used as a daily drink across the world.

The present study was aimed to explore aromatic composition, catechins content, and metal elements (MEs) profiling of forty-three black tea samples collected across Iran.

Black tea samples were prepared from the Iranian Tea Research Institute. MEs content of the plant dried samples was measured by atomic absorption spectrometer. Aromatic composition and catechins content of the studied samples were analyzed by GC-FID, GC-MS and HPLC, respectively.

Hexanal (0.3-27.6 %), cis-linalool oxide (0.1-44.7 %), trans-linalool oxide (0.2-48.3 %), linalool (0.2-39.2 %), benzyl alcohol (0.2-38.9 %), phenylethanol (0.1-37.9 %), and (-)-Myrtenol (4.4-26.8 %) were the major volatile oil compounds of the studied samples. The highest content of hexanal, cis-linalool oxide, trans-linalool oxide, linalool, benzyl alcohol, phenylethanol and (-)-Myrtenol was measured in IR5 (Zarin), IR13 (Leil 1), IR23 (Shariat), IR31 (Roozmehr 1), IR34 (Noshiran), IR36 (Roozmehr 3) and IR18 (Amard 2), respectively. Catechin content was ranged from 0.589 ± 0.0285 in IR32 (Roozmehr 2) to 0.65 ± 0.0088 in IR29 (Aramgol 1). The level of the copper, Iron and lead were generally within the safe limitation mentioned in the world.

Sample of Roozmehr was characterized with high aromatic compounds, catechins content, and low level of MEs. This information can be interestingly considered by food industrials to process black tea products.

Indole alkaloids are a class of alkaloids enclosing a structural moiety of indole; numerous indole alkaloids also comprise isoprene groups and are thus named terpene indole or secologanin tryptamine alkaloids and have more than 4100 identified diverse compounds. Indole alkaloids are one of the main classes of alkaloids identified in several significant plant groups, mainly Catharanthus and Rauvolfia plants from Apocynaceae family. The pharmacological actions of these plants have been studied scientifically, with some undergoing clinical trials while others were already approved for medicinal use. This review aimed at the fundamental objective of summarizing the developed analytical methods for quantification of indole alkaloids obtained from plants and complete examination of their present quantification method, which may result in the identification of alternative method developments for the effective and accurate quantification of indole alkaloids by considering the green method. This systematic review was conducted from January 2006 to June 2022, using electronic databases like PubMed, Web of Science and Embase. Several studies in the literature have been reported for quantitative estimation of indole alkaloids using different techniques including the spectrophotometric methods, high performance liquid chromatography (HPLC), and ultra-performance liquid chromatography-mass spectrometry (UPLC-MS). Most of the studies reported HPLC analysis for quantification. This review will offer a greater understanding of the available methods to develop a more precise and sensitive quantification method for indole alkaloids with the cost-effectiveness that is expected to emerge in line with clinical usage and to promote the development of the pharmaceutical industry for routine quality control analysis.

Scutellaria bornmuelleri Hausskn. ex Bornm. ssp. mianensis Rech.f is one of the species of Scutellaria genus, Lamiaceae, that have long been used in traditional medicine. The aim of this study was to analyze the methanol extract of aerial parts of the plant.

Chemical composition of methanol extract of S. bornmuelleri aerial parts was determined using gas chromatography/mass spectrometry (GC/MS).

A total of 113 compounds were identified in the methanol extract of S. bornmuelleri shoot. The main compounds were organic acids (23.649%), aldehydes (14.516%), ketones (11.353%), alcohols (5.439%), carbohydrates (3.85%), methyl esters (3.713%), sugars (1.953%), acetates (1.933%), terpenes (2.522%), metal related compounds (1.229%), amides (1.169%) and other compounds (9.423%). Pentacosane (1.021%) was identified as the main carbohydrate, n-hexadecanoic acid (4.1%) as the major acid, 5-hydroxymethylfurfural (10.063%) as the main aldehyde, 4H-Pyran-4-one, 2,3-dihydro-3,5-di hydroxy-6-methyl- (2.289%) as the main ketone, syringol (2.395) as the main alcohol, phytol (0.66%) as the main terpene, isopropyl acetate (0.728%) as the main acetate, propanoic acid, 2-oxo-, methyl ester (1.298%) as the main methyl ester, 9-octadecenamide, (Z)- (0.685%) as the main amide, d-glycero-d-ido-heptose (0.532%) as the main sugar, and (4H)1,3,2-dioxaborin, 4-ethenyl-4, 6-diethyl-5-(1-methylethyl)- (0.514%) as the main metal related compound.

The presence of different compounds with known bioactivities can make this plant a suitable medicinal plant for supplementary medication for various diseases. 

Rosa damascena Mill. (Rosaceae) is a relevant ornamental and medicinal flower, whose distillation is known as Golab (Rosewater) in Iran. Due to the nature of the distillation process, methanol and ethanol are likely to be formed in the final product. Therefore, due to their toxicity, along with their frequent prescription, this study aims to investigate the concentrations of essential oil, methanol, and ethanol in commonly used brands of Rosewater available in Tehran, Iran.

Methanol and ethanol concentrations were determined by gas chromatography, using a Flame Ionized Detector.

The mean essence level in the tested samples was 204.1 ± 18.0 ppm, which was significantly higher (P < 0.001) than the Iranian standard level. The mean methanol and ethanol levels in the tested samples were 1.25 ± 0.70 ppm and 700.0 ± 100.0 ppm, respectively, which were significantly lower than the maximum residues levels.

The mean essence level in the tested samples well coped with the Iranian standard level. Moreover, there is no health risk to methanol and ethanol through Rosewater consumption

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 selfadministration of prescription drugs has been increasingly reported in India. Urinalysis as an adjunct to selfreport 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.

The Oil content, fatty acid compositions of pistachio nut (Pistacia vera L.) samples corresponding to four different varieties (Achouri, Adjmi, Batouri and Mateur), all cultivated in Algeria were determined. The fatty acid profiles of four main commercial pistachio varieties, were determined by gas chromatography: palmitic (C16:0), palmitoleic (C16:1), Margaric (C17:0), Margarolic (C17:1), stearic (C18:0), oleic (C18:1), linoleic (C18:2), and linolenic (C18:3), Oleic acid has been found as the most common monounsaturated fatty acid. Linoleic acid has the highest percentage among polyunsaturated fatty acids. There have been significant differences among pistachio cultivars regarding unsaturated fatty acids. Based on the oleic to linoleic acid (O/L) ratio, a quality index was determined for these four varieties: Achouri (3.39)  Batouri(3.12)  Adjmi (2.89)  Mateur (2.88). PCA analysis showed the pistachio varieties division into three distinct groups: Adjmi and Mateur (rich in C18.2), Batouri (rich in C16.1, C18.3 and C18.1), Achouri (rich in C16.0, C18.1).

There is insufficient evidence on the effectiveness of gastric lavage in organophosphorus poisoning. This study was done to quantitate the level of chlorpyrifos and quinalphos retrieved in gastric lavage fluid. Patients presenting within six hours of ingesting quinalphos or chlorpyrifos with International Program on Chemical Safety Poison Severity Score (IPCS PSS) grade 2 or more were included in the study. After the stabilisation of patients, gastric lavage was performed with alliquotes of 200 ml of normal saline till aspirate became clear. Quantification of the pesticide was done in the first 10 ml of lavage fluid aspirated out and in blood with gas chromatography with triple quadruple mass spectrometer (GC-MSMS). There were six patients in each pesticide group. Mean time for reaching hospital after the ingestion of pesticide was 2.8 ± 1.1(range 1.25-6) hours. Median quantity of chlorpyrifos in the lavage fluid was 10.24 (IQR 14.36) µg/L and in quinalphos, it was 1360.62 (IQR 1691.2) µg/L. Other compounds detected in lavage fluid and confirmed in blood were endosulfan, diazinon, pirimiphos, pyridafenthion, pyrazophos, pirimiphos ethyl, and azinphos. Chlorpyrifos and quinalphos are detected in lavage fluid after one hour of ingestion and few milligrams are retrieved by gastric lavage. The presence of other pesticides including endosulfan were confirmed in lavage fluid.

Today, food enrichment is one of the most widely used methods in benefiting the food processing industry. The effects of four different dietary groups [basic diet (I), basic diet+flaxseed oil (II), basic diet+non-absorbable fiber+flaxseed oil (III)& basic diet+non-absorbable fiber+fish oil (IV)] were studied on the development of eggs with high content of long-chain omega-3 fatty acids &vitamin D3. To achieve this goal, the egg yolk oil was extracted by the cold extraction method and analyzed by gas chromatography. A total of 24 fatty acid compounds were identified in egg yolk oil, which ~48-52% of contained monounsaturated fatty acids (mainly oleic acid). The diet modifications significantly (p<0.05) increased the total content of egg yolk omega-3 fatty acids, and the highest value was observed in the diet (III) (84.2% increase compared to the control). The highest elevations were observed in ALA (3.49%), DPA (0.24%), and DHA (1.21%) fatty acids. Also, the ratio of ω-6/ω-3 fatty acids was ~18.36% in the control group (I), while in the diets II, III, and IV, the ratios decreased to ~3.79 (~80%), ~3.16 (~83%), and ~6.09 (~67%), respectively. Overall, the results indicated that diet (III) & (IV) were the most effective to increase the content of omega-3 fatty acids and Vit-D3 in egg yolk, respectively.

Pollution of water resources with pesticides is one of the environmental problems and a serious threat to the communities’ health. This study aimed to determine the residual concentration of pesticides in urban drinking water networks of Hamadan province in 2019. In order for investigating the residual concentration of organochlorine (aldrin, dieldrin, lindane, methoxychlor and permethrin), organophosphorus (chlorpyrifos, diazinon and malathion), and carbamate (atrazine and alachlor) pesticides in urban drinking water distribution networks of the province, a total of 46 samples were taken. The samples were analyzed by GC-ECD and the results were analyzed using Excel software (a descriptive cross-sectional study). The residues of aldrin, dieldrin, lindane, diazinon, malathion, atrazine, and alachlor were found in none of the samples. The maximum concentrations of chlorpyrifos and permethrin were 2.20 and 8.03 μg/L, respectively. The methoxychlor residue was observed only in one sample (C=0.35 μg/L) and all other samples were free of methoxychlor. Residues of studied pesticides in all samples are much less than the maximum allowable in the national standard and the World Health Organization (WHO) and Environmental Protection Agency (EPA) guidelines. Therefore, it can be concluded that the studied networks water quality as well as the urban drinking water resources in Hamadan province are at a very desirable level in terms of the pesticide residues. If the consumption of pesticides is not controlled, there is a possibility of increasing the concentration of these pollutants in water resources, which in turn may threaten the human health in the future.

Breast milk composition is affected by several factors such as maternal diet and body mass index. Milk fats include a major calorie content of the milk, which changes dramatically throughout the lactation. The aim of the present study was to assess breast milk fatty acid profile in overweight and obese mothers and its correlations with maternal body mass index.

Milk samples were collected from 73 healthy lactating women referring to various health centers in Mashhad. Data were collected using food frequency questionnaire to assess the maternal dietary intakes. Breast milk fatty acid profile was assessed using gas chromatography.

Breast milk content of saturated fatty acids was higher in obese mothers than overweight mothers (p = 0.03) with positive correlations with maternal body mass index (r = 0.256; p = 0.037). Furthermore, breast milk monounsaturated fatty acids were negatively correlated with pre-pregnancy body mass index (r = -0.385; p = 0.003) and pre-pregnancy body weight (r = -0.276; p = 0.026). However, no significant correlations were observed between the maternal body fat mass and fat proportion with the breast milk fatty acids (p > 0.05). Moreover, no significant associations were seen between dietary saturated fatty acids, milk monounsaturated fatty acids, polyunsaturated fatty acids, n-3 polyunsaturated fatty acids and n-6 polyunsaturated fatty acids with the corresponding fatty acids in breast milk (p > 0.05).

Based on the results, breast milk of the obese mothers included higher proportion of saturated fatty acids, while no significant differences were observed in the contents of milk monounsaturated fatty acids and polyunsaturated fatty acids between the overweight and obese women. Furthermore, maternal pre-pregnancy body mass index was negatively correlated with the contents of milk monounsaturated fatty acids, while it was positively correlated with saturated fatty acids contents.

Armenian cucumber (Cucumis melo var. flexuosus) is one of the varieties of Cucurbitaceae family that is freshly consumed in Iran, while due to the presence of useful fatty acids and minerals, it can play a special role in the health diet. The aim of this study was to evaluate the quantitative and qualitative of fatty acids in the seeds of Armenian cucumber.

Fruits were harvested in summer of 2018 at a fully ripened stage.The seeds were manually separated from the fruits and dried in roomtemperature. Evaluation of morphological traits was performed in the laboratory of horticulture sciences department. The seed oil extraction was done using Soxhlet apparatus and fatty acids analysis was performed by gas chromatography at Central Research Institute of Islamic Azad University, Isfahan (Khorasgan) Branch.

The mean of 100-seed weight was 4.08 g, the mean of seed length and diameter were 12.46 and 4.84 mm, respectively, andthe ratio of kernel to seed shellwas 2.75. The seed oil content was 34.8% and included of 24 kind of different fatty acids. The most important unsaturated fatty acids were linoleic with 51.62% and oleic acid with 28.31% and the most important saturated fatty acids were palmitic and stearic acids with 11.16% and 7.16%, respectively. The sum of unsaturated fatty acids, saturated fatty acids and the ratio of unsaturated to saturated fatty acids were 19.46, 80.54 and 4.13, respectively.

According to the results of this research, America cucumber seeds are rich in polyunsaturated fatty acids that will make them suitable for food, pharmaceutical and industrial applications.

 Organophosphates (OPPs) are toxic chemicals that can cause serious health problems through poisoning water and food.

 A very simple and fast disperser-less liquid microextraction strategy before chromatographic detection was designed for the analysis of organophosphates in various water solutions.

 A 60 µL aliquot of chloroform, as extraction solvent (without using disperser), was introduced into the sample solution by rapid injection, and the sedimented organic phase was analyzed to assay some organophosphates.

 Analytical characteristics, including limits of detection (0.0003 - 0.001 µg.L-1), linear dynamic ranges (0.001 - 100 µg.L-1), relative standard deviations (2.5 - 10), enrichment factors (up to 238), and extraction recoveries (84% - 108%), indicated the high efficacy of the developed method for analyzing the target analytes.

 The proposed procedure was effectively used for the analysis of the OPPs in real tap water, river water, and fruit juice samples. In the present study, the examined analytes were in the range of 0.07 - 1.56 µg.L-1.

A simple, fast, efficient, and environmentally friendly microextraction technique named salt induced liquid-liquid extraction combined with amine based deep eutectic solvent-dispersive liquid-liquid microextraction method followed by gas chromatography-flame ionization detector was applied for the determination of some anti-seizure drugs in urine samples.

In this method, sodium chloride (30% w/v) was dissolved in the sample solution (adjusted at pH=10) as phase separation agent and iso–propanol was added to the solution. After manually shaking, the solution was centrifuged and the supernatant phase was removed and mixed with choline chloride: benzyl ethylenediamine (85 µL) and the mixture was rapidly dispersed into a deionized water containing 5.0 % w/v, sodium chloride and adjusted at pH=10. The cloudy solution was centrifuged and the sedimented phase was removed and 1 µL of it was injected into the determination system.

Under final conditions, the limits of detection and quantification at the ranges of 3.4-6.9, and 11.5-23.3 ng mL-1 were obtained, respectively. The relative standard deviations for intra- and inter day assays were lower than 10.9%. The effect of exogenous and endogenous effect on the performance of the method was studied and the results showed that these factors were nearly effect less on the efficiency.

The introduced method was satisfactorily utilized to determinate the selected benzodiazepines drugs in the patients’ urine samples.