Gas Chromatography-flame Ionization Detector Research Articles

Determination of Nicotine Contents in Local and Imported Cigarettes Smoke in Yemeni Markets Using Gas Chromatography Flame Ionization Detector (GC-FID)

Determination of Nicotine Contents in Local and Imported Cigarettes Smoke in Yemeni Markets Using Gas Chromatography Flame Ionization Detector (GC-FID)

Stability of Nano-Emulsified Cannabidiol in Acidic Foods and Beverages.

Introduction: Food and beverage products containing cannabidiol (CBD) is a growing industry, but some CBD products contain Δ9-tetrahydrocannabinol (Δ9-THC), despite being labeled as "THC-free". As CBD can convert to Δ9-THC under acidic conditions, a potential cause is the formation of Δ9-THC during storage of acidic CBD products. In this study, we investigated if acidic products (pH ≤ 4) fortified with CBD would facilitate conversion to THC over a 2-15-month time period. Materials and Methods: Six products, three beverages (lemonade, cola, and sports drink) and three condiments (ketchup, mustard, and hot sauce), were purchased from a local grocery store and fortified with a nano-emulsified CBD isolate (verified as THC-free by testing). The concentrations of CBD and Δ9-THC were measured by Gas Chromatography Flame Ionization Detector (GC-FID) and Liquid Chromatography with tandem mass spectrometry (LC-MS/MS), respectively, for up to 15 months at room temperature. Results: Coefficients of variation (CVs) of initial CBD concentrations by GC-FID were <10% for all products except ketchup (18%), showing homogeneity in the fortification. Formation of THC was variable, with the largest amount observed after 15 months in fortified lemonade #2 (3.09 mg Δ9-THC/serving) and sports drink #2 (1.18 mg Δ9-THC/serving). Both beverages contain citric acid, while cola containing phosphoric acid produced 0.10 mg Δ9-THC/serving after 4 months. The importance of the acid type was verified using acid solutions in water. No more than 0.01 mg Δ9-THC/serving was observed with the condiments after 4 months. Discussion: Conversion of CBD to THC can occur in some acidic food products when those products are stored at room temperature. Therefore, despite purchasing beverages manufactured with a THC-free nano-emulsified form of CBD, consumers might be at some risk of unknowingly ingesting small amounts of THC. The results indicate that up to 3 mg Δ9-THC from conversion can be present in a serving of CBD-lemonade. Based on the previous studies, 3 mg Δ9-THC might produce a positive urine sample (≥15 ng/mL THC carboxylic acid) in some individuals. Conclusion: Consumers must exert caution when consuming products with an acidic pH (≤4) that suggests that they are "THC-Free," because consumption might lead to positive drug tests or, in the case of multiple doses, intoxication.

Analysis of ethanol content in commercially available Hand sanitizers in Oman using Gas Chromatography- A comparative study

The demand and usage of alcohol-based hand sanitizers have immensely increased worldwide in recent times as a protective measure against COVID-19 and other infectious diseases. To ensure that the public and health workers get hand sanitizers with an alcohol percentage within the label stated range, quality control of these products must be carried out by the governmental authorities. The study was designed to determine the ethanol content of eight commercially available and commonly used hand sanitizer gels available in the Omani market. Eight hand sanitizer gels were collected from various community pharmacies and commercial stores in Oman. The Gas Chromatography-Flame Ionisation Detection (GC-FID) method was employed to analyse ethanol content as it is one of the easiest, most reliable and most accurate methods for the determination of volatile content. Various physical properties of the samples such as pH, density, and refractive index, were also evaluated for comparison purpose. Sample prices were also compared from a pharmacoeconomic point of view. The majority of the hand sanitizers fell within the WHO recommendation range, with ethanol levels in the range of 66% to 76%, except A-7, which was below the recommended concentration for pathogenic microbial inactivation. The five of the samples tested showed ethanol contents below the labelled claim, whereas two sanitizers, A-1 and A-2, had ethanol contents above the labelled claim. The hand sanitizers differed significantly in price and certain physical properties which are likely to influence consumer preferences. Although the hand sanitizer products met the WHO requirements for alcohol content, the authors recommend that the regulatory authority should do a frequent testing of the samples available in the market to ensure quality and safety of these products.

Geological and geochemical characterization of caprock integrity in the Athabasca oilsands region

Caprocks play a pivotal role in petroleum systems for the accumulation of oil and gas, as well as in processes such as steam injection for heavy oil recovery and geological storage of CO2. In this study, the geological and geochemical characteristics of the caprock from the Cretaceous Wabiskaw Member (Mbr.) and overlying Clearwater Formation (Fm.), situated above the Athabasca oil sand region, were thoroughly examined using core samples obtained from well 1-22-90-14W4. Through HAWK programmed pyrolysis and solvent extraction, the caprock succession was revealed to exhibit limited organic content with total organic carbon content < 2.0 wt% and extractable organic matter (EOM) < 200 ppm. Further analysis using gas chromatography-flame ionization detector and gas chromatography-mass spectrometry on EOM unveiled insights into the mixing dynamics between the underlying oil reservoir and the caprock indigenous materials. Distinct trends in the ratios of low molecular weight (LMW) aromatic hydrocarbons, N-shielded carbazole, benzo[c]carbazole, and concentrations of carbazoles and benzocarbazoles were evident within a 5-m distance from the caprock-reservoir contact, indicating significant fractionation among compounds. Enrichment of these compounds was observed in the shale of the Wabiskaw Mbr., with a reversal of trends occurring within the initial 5 m into the overlying shale of the Clearwater Fm., suggesting limited oil penetration into the shale. The main Clearwater Fm. caprock succession was characterized by a dominance of immature, indigenous terrigenous organic matter, along with background concentrations of carbazole and benzocarbazole and an absence of N-shielded and/or LMW compound preferences. This composition starkly differed from the oil found in the underlying reservoir. The presence of calcareous cements in the Clearwater Fm. shale, approximately 5 m above the base, characterized by high bulk density (with 62% siderite), low porosity, and matrix permeability, contributed significantly to enhancing the sealing capacity of the caprock. The overall results provide compelling evidence that vertical oil leakage from the McMurray Fm. reservoir through the overlying shale of the Clearwater Fm. has not occurred during the post-lithification history with exception of the lower-most 5 m. The clay-rich argillaceous units identified in this study emerge as potential candidates for serving as effective caprock seals for steam injection and CO2 storage.

Antiviral and cytotoxic activities and chemical profiles of two species of Abies nordmanniana from Türkiye.

Abies is an important genus of the family Pinaceae, with about 50 species found in the highlands of Asia, Europe, North Africa, and North and Central America. The principal aim of the present work was to investigate the chemical content and biological potential of the resin and cone from Abies nordmanniana subsp. bornmulleriana and Abies nordmanniana subsp. equi-trojani, respectively. The flavonoid and phenolic contents of the resin and cones were evaluated using liquid chromatography-high resolution mass spectrometry (LC-HRMS). Additionally, the essential oil and fatty acid compositions were analyzed using gas chromatography-mass spectrometry (GC-MS) and gas chromatography-flame ionization detector (GC-FID), respectively. Cytotoxicity of the extracts and essential oils were screened against certain cancer cell lines, namely, human prostate adenocarcinoma cell line (PC3), human lung adenocarcinoma cell line (A549), human pancreatic cancer cell line (PANC-1), human hepatocellular carcinoma cell line (HepG2), human breast cancer cell line (MDA-MB231), and normal human lung fibroblast cell line (CCD-34-LU), with MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide] assay. According to the MTT results, hexane extracts of both cone (CH) and resin (RH), ethanol-water (CEW), dichloromethane (CD), and acetone (CA) extracts of the cone mostly inflict cytotoxicity in HepG2 cell line. Antiviral activities of Abies nordmanniana subsp. extracts at doses of 5 μg/g and 10 μg/g were also evaluated in ovo for their virucidal activity against avian coronavirus. Abies nordmanniana subsp. extracts exhibited concentration-dependent antiviral activity on specific pathogen-free embryonated chicken eggs. Significantly, cone acetone extract (CA), cone ethanol extract (CE), and cone dichloromethane extract (CD) of Abies nordmanniana subsp. exhibited strong inhibition of the virus at a concentration of 10 μg/g. The most potent virucidal activity was observed with ethanol-water extract of conifer form (CEW). According to these results, it was proved that Abies nordmanniana species could be a potential, sustainable, and renewable drug source, especially considering the impressive antiviral and significant cytotoxic activity potentials.

Chemical composition, anticholinesterase activity, and molecular docking studies of Piper crassipes Korth. ex Miq. essential oil

The purpose of this study was to investigate the chemical composition and anticholinesterase inhibitory activity of the essential oil obtained from Piper crassipes leaves collected from Malaysia. Twenty-two components were identified using gas chromatography-flame ionisation detection (GC-FID) and gas chromatography/mass spectrometry (GC-MS), which represent 97.8% of the essential oil. The identified major components included chavibetol (59.8%), chavibetol acetate (10.4%), γ-muurolene (5.4%), and germacrene D (4.6%). Anticholinesterase activity was assessed using Ellman’s method. A moderate inhibitory effect was observed for acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes with IC50 values of 77.2 ± 0.2 and 89.2 ± 0.2 µg/mL, respectively. The molecular docking studies revealed that chavibetol acetate showed potent interactions with the cholinesterase target, while other compounds exhibited varied binding patterns, providing crucial insights into their potential as cholinesterase inhibitors.

Risk assessment of PAHs in dusts from surfaces of abandoned automobiles at auto-workshops of three semi-urban areas of Eastern Nigeria: Compositional patterns and source apportionments

The concentrations, sources, compositional patterns, and risk assessments of PAHs in dust on abandoned automobiles at auto-workshops in three semi urban areas were studied. Dust samples were randomly collected from at least five car surfaces in automobile workshops located at Rumuodomaya-Ogale, Ekwulobia, and Awka between December 2019 and March 2020, and analysed for PAHs using the Buck M910 Gas Chromatography-Flame Ionization Detector. Car surface dust from Rumuodomaya-Ogale showed the highest PAH concentration of 2.348 µg/g in March 2020, while that of Awka had the lowest total PAH concentration of 0.129 µg/g in February 2020. Dust from the Ekwulobia consisted mostly of 3-ring PAHs throughout the month, except in January 2020. Rumuodomaya-Ogale dust had high BaPTEQ values, indicating a potential carcinogenic risk for automobile workers. Considerable cancer risk may arise from prolonged exposure of adult’s automobile workers to PAHs in dust via dermal contact and inhalation. The ingestion cancer risk values for children were higher than adult counterparts (except in Awka, December 2019). The principal component analysis suggested the influence of exhaust emissions on the source of PAHs in dusts of automobile workshops. There is a need for automobile workers to have and wear personal protection equipment (PPE) while on duty to reduce the risk associated with exposure to PAHs in dust particles.

Determination of Phytochemical Constituents in Cnidoscolus aconitifolius Leaves Extracts by GC-FID

Cnidoscolus aconitifolius, commonly called ‘Chaya’ and in Southeastern Nigeria ‘hospital too far’, or ‘catholic vegetable’ is a medicinal plant from the family Euphorbiaceae that has been used since pre-Columbian times as food and in treating diseases. The aim of this study was to determine the phytochemicals present in the ethanol, methanol, and aqueous extracts of Cnidoscolus aconitifolius leaves, which could be accountable for the plant’s acclaimed therapeutic properties, using Gas Chromatography-Flame Ionization Detector (GC-FID) technique. Cold maceration was used in the extraction process while GC-FID was employed for the qualitative and quantitative analysis. The phytochemical screening revealed the presence of lunamarine, cardiac glycoside, anthocyanin, spartien, cyanogenic glycoside, flavonones, steroids, keampferol, epicatechin, flavones, oxalate, resveratol, sapogenin, epihedrine, flavan-3-ol, proanthocyanin, naringin, ribalinidine, naringenin, catechin, tannin, rutin, and phytate. However, the extracts did not all contain the same phytochemicals nor quantity of phytochemicals. While the ethanol extract recorded phytate (18.9224µg/ml) as the highest yield, methanol had spartein (17.2035µg/ml) and the aqueous extracts had epicatechin (9.2402 µg/g). The presence of these pharmacologically active substances, which has been researched to have antimicrobial, anti-diabetic, anti-oxidant, and anti-inflammatory properties amongst others, supports the efficacy of Cnidoscolus aconitifolius leaves in treatment of various pathologies and use in ethnopharmacology. It also projects Cnidoscolus aconitifolius leaves as a probable raw material for antibiotic formulation.

Toxicity and Repellent Activity of Hedychium flavum Rhizome Essential Oil and Major Constituents Against Stored Product Insects1

Abstract An essential oil extracted from the rhizome of wild ginger, Hedychium flavum Roxburgh (Zingiberaceae), was evaluated for its toxic and repellent activity against adults of the stored product pests Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae), Lasioderma serricorne (F.) (Coleoptera: Anobiidae), and Liposcelis bostrychophila Badonnel (Psocoptera: Liposcelididae). Gas chromatography–flame ionization detection and gas chromatography–mass spectrometry revealed 24 compounds that composed 90.52% of the constituents of the extracted oil. The main compounds identified were β-pinene (33.52%), linalool (15.56%), and 1,8-cineole (11.20%). These three compounds and the rhizome essential oil were further assayed for their contact toxicity, fumigant, and repellent properties against the three stored product pests. Contact toxicity bioassays determined median lethal dosages (LD50 values) of the essential oil as 22.3 µg/adult for T. castaneum, 11.3 µg/adult for L. serricorne, and 109.9 μg/cm2 for L. bostrychophila. Analysis of the fumigant toxicity bioassay established LC50 values of 15.6 mg/L air for T. castaneum and 7.6 mg/L air for L. serricorne. The rhizome essential oil had higher repellent activity against the three stored product pests. Our results indicate the potential of the essential oil from rhizomes of H. flavum and its three main components as potential botanical insecticides for management of stored product pests.

Effect of post-harvest drying period on the chemical composition of Zingiber zerumbet Sm. Rhizomes essential oil and its biological activities.

Zingiber zerumbet Sm. (Family: Zingiberaceae) is an important perennial medicinal oil-bearing herb that is native to the Southeast Asia. This study examines the impact of different durations of post-harvest shade drying (ranging from 1 to 12months) on essential oil yield and chemical composition of Z. zerumbet, in comparison to the freshly collected oil sample. This study explores how post-harvest shade drying impact the composition and longevity of Z. zerumbet rhizomes as well as its antimicrobial, antibiofilm activity. The oils were analyzed for their chemical composition analysis using a gas chromatography-flame ionization detector (GC-FID) and gas chromatography-mass spectrometry (GC-MS). The post-harvest periods of drying (1-12months) were discovered to enhance the concentration of marker constituents in the oil. The primary constituent, Zerumbone, was detected in concentrations ranging from 69.38 ± 5.63% to a maximum of 80.19 ± 1.53% as the drying duration of the rhizome was extended. The output of the essential oil was not significantly affected by drying times; however, it did have a noticeable impact on the proportions of monoterpenes. Both disc diffusion and broth microdilution assay were used in freshly collected Z. zerumbet oil for its antimicrobial potential against S. aureus, L. monocytogens, S. hominis, Salmonella enterica serovar Typhimurium, P. aeruginosa, S. intermedius, E. coli, and C. albicans. For the first time, the oil reported to exhibit antibiofilm activity against S. aureus which was validated using fluorescence microscopy, and effectively disrupts the biofilm by 47.38% revealing that essential oil was able to disintegrate the clusters of the pathogen. Z. zerumbet rhizome oil is effective to reduce food-borne microorganisms. Therefore, its essential oil, a natural source of bioactive zerumbone, may improve flavor, aroma, and preservation.

Physical activity (PA) impact on metabolome and immunity of oncogene addicted non-small cell lung cancer (NSCLC): The EXcellenT trial.

e20582 Background: Today patients (pts) with oncogene addicted advanced NSCLC receive molecular targeted therapies as first-line treatment ensuring high compliance to therapy, few side effects and long survival time. These pts are usually young and with a strong wish to regain the pre-diagnosis quality of life (QoL), including the ability to perform PA. It’s known that PA can impact significantly on metabolomic and immunity status, but to date only few studies on its role in NSCLC have been performed. The aim of the EXcellenT trial is to evaluate if a tailored PA program may have an impact on QoL and performances of this homogeneous subgroup of pts. An exploratory objective was to explore the complex interplay between PA and immune status and the influence of PA on metabolome. Methods: EXcellenT (Exercise in Extended oncogene addicted Lung Cancer in Active Treatment - NCT05306652) is an Italian monocentric prospective study enrolling 40 pts with oncogene-addicted advanced NSCLC in active treatment with tyrosine kinase inhibitors (TKI). Pts are randomized in 2 arms: an interventional arm of a personalized supervised PA program or a counselling group of home-based exercise. We explored peripheral variations of T cells subsets during TKI treatment combined with exercise training to better define the immuno-dependence of these tumors. Fatty acid composition (FA) of plasma has been carried out using gas chromatography-flame ionization detection (GC-FID) and liquid chromatography-mass spectrometry (LC-MS). Immature and mature neutrophils, monocytes, CD34+ cells and megakaryocytes (MK) precursors have been determined through flow cytometry analysis. Results: A preliminary exploratory analysis on the first patients enrolled with 3 complete time point (baseline; week 4 and 12) was performed. To date 23 out of 40 pts have been enrolled, 46% of them with pre-diagnosis leisure-time physical activity. The oncogene identified are: ALK 52%, EGFR 26%, BRAF 9%, RET 4%, ROS1 9%. 35% had stable brain metastasis (mts) and 39% bone mts not at risk of skeletal-related events. FA analysis (4 pts) showed significant increase of monounsaturated fatty acids (p = 0.0329) during the study. According to immunophenotype, we observed (3 pts) a significant reduction of CD34+ cancer stem cell (p 0.0112) and a consistent increase in mature CD66b+CD10+ neutrophils with a trend of decrease in CD66b+CD10- cells. Conclusions: The ExcellenT trial is showing that PA programs are feasible and well accepted by patients with oncogene-addicted NSCLC. The QoL analysis will be performed at the end of enrolment. The preliminary analysis on metabolomic and immunity status shows an improvement of fatty acid composition and an increase of mature cell precursors compared to immature counterpart suggesting a potential role of PA in hindering tumor immune escape strategies. Clinical trial information: NCT05306652 .

Fluorodeschloroketamine found as a street drug in drug seizures and drug driving cases in Hong Kong

BackgroundWith the decline of the use of ketamine, one of the common drugs of abuse in Hong Kong, detection of ketamine-related analogues in local laboratories has been encountered. Aim: A brief account of the occurrence of fluorodeschloroketamine (FDCK) in forensic cases is reported through a retrospective study of all drug seizures and driving under the influence of drugs (DUID) cases since its first appearance. Methods: Identification of FDCK in drug seizures was achieved through gas chromatography – mass spectrometry (GC-MS) and/or liquid chromatography – diode array detection (LC-DAD) methods while its quantification was performed using gas chromatography – flame ionization detection (GC-FID). For the analysis of blood samples in DUID cases, identification and quantification were performed using LC-MS/MS by monitoring the respective transitions of FDCK and fluorodeschloronorketamine (FDCNK) using ketamine-d4 and norketamine-d4 respectively as internal standards. Results: Since its first submission in November 2018, a total of 74 drug seizure cases (151 items) and 6 drug driving cases were encountered till December 2019. Drug seizures found with FDCK were physically similar to those of ketamine seizures. The majority of items were detected with FDCK only (103 items, ∼67%) or as a mixture of FDCK with ketamine (42 items, ∼28%). The drug purity detected with either FDCK only or FDCK mixed with ketamine was high which was similar to those purity found in ketamine seizures. The blood drug concentrations of FDCK of the 6 drug driving cases were in the range of <0.002–1.1 μg/mL and other psychoactive drug(s)/metabolite(s) were also identified. Except for one case where the analysis of the metabolite, fluorodeschloronorketamine (FDCNK), was not conducted due to insufficient sample, the FDCK (FDCNK) concentrations in blood found in the 6 cases were <0.002 (0.005), 0.002 (0.002), 0.002 (0.003), 0.02 (0.035), 0.87 (0.44) and 1.1 (not determined) μg/mL. Conclusions: With the drug seizures found with FDCK resembled in physical appearance with ketamine seizures, users might likely misuse it as ketamine. Though complicated by other drugs found, it is speculated that the two cases with higher concentration of FDCK found in blood (1.1 and 0.87 μg/mL) might have contributed to the impairment observed.

The Valorization of Spanish Minority Grapevine Varieties—The Volatile Profile of Their Wines as a Characterization Feature

Despite the large number of existing varieties of Vitis vinifera L., only few occupy a large niche in today’s highly globalized wine market. The increasing consumer demand for diversified products, as well as the changing climatic conditions, make establishing a process of varietal diversification essential to achieve both challenges. It is for this reason that the study of minority varieties, which have a higher level of adaptation to each area of origin, is of particular interest. With the main objective of achieving an in-depth knowledge of minority varieties in Spain, the national research project ‘Valorization of Minority Grapevine Varieties for their Potential for Wine Diversification and Resilience to Climate Change’ (MINORVIN), has been proposed. Within this extensive project, the present study describes the aroma profiles of 60 single-variety wines, corresponding with 44 different varieties, with 12 of these varieties being studied at the same time in several Spanish regions. Volatile compounds were determined through three consecutive vintages using gas chromatography-mass spectrometry (GC-MS) and gas chromatography–flame ionization detector (GC-FID). Compounds were grouped into major compounds, including alcohols, C6 compounds, esters, acetates, acids, carbonyl compounds, and other type of compounds, and minor compounds, including lactones, terpenes, and C13-norisoprenoids, according to their concentration in the wines being analyzed. Among this last group of compounds, lactones were quantitatively the most abundant, followed by terpenes. This study reflects that minority variety wines show distinctive aromatic profiles, supporting the importance of valuing and promoting the autochthonous minority grapevine varieties for the Spanish winemaking industry.

MOF-derived porous carbon microspheres Ni@C-acid as solid-phase microextraction coating for extraction of polycyclic aromatic hydrocarbons from tea infusions

The improvement of the stability and adsorption properties of materials on targets in sample pre-treatment has long been an objective. Extensive efforts have been made to achieve this goal. In this work, metal-organic framework Ni-MOF precursors were first synthesized by solvothermal method using polyvinylpyrrolidone (PVP) as an ideal templating agent, stabiliser and nanoparticle dispersant. After carbonization and acid washing, the nanoporous carbon microspheres material (Ni@C-acid) was obtained. Compared with the material without acid treatment (Ni@C), the specific surface area, pore volume, adsorption performance of Ni@C-acid were increased. Thanks to its excellent characteristics (high stability, abundant benzene rings), Ni@C-acid was used as fiber coatings in headspace solid-phase microextraction (HS-SPME) technology for extraction and preconcentration of polycyclic aromatic hydrocarbons (PAHs) prior to gas chromatography-flame ionization detector (GC-FID) analysis. The experimental parameters of extraction temperature, extraction time, agitation speed, desorption temperature, desorption time and sodium chloride (NaCl) concentration were studied. Under optimal experimental conditions, the wide linear range (0.01-30 ng mL−1), the good correlation coefficient (0.9916-0.9984), the low detection limit (0.003-0.011 ng mL−1), and the high enrichment factor (5273-13793) were obtained. The established method was successfully used for the detection of trace PAHs in actual tea infusions samples and satisfied recoveries ranging from 80.94-118.62 % were achieved. The present work provides a simple method for the preparation of highly stable and adsorbable porous carbon microsphere materials with potential applications in the extraction of environmental pollutants.

Chemical composition and biological activities of essential oils of seven Cultivated Apiaceae species

The Apiaceae family contains many species used as food, spice and medicinal purposes. Different parts of plants including seeds could be used to obtain essential (EO) oils from members of the Apiaceae family. In the present study, EOs were components obtained through hydrodistillation from the seeds of anise (Pimpinella anisum), carrot (Daucus carota), celery (Apium graveolens), dill (Anethum graveolens), coriander (Coriandrum sativum), fennel (Foeniculum vulgare), and cumin (Cuminum cyminum). EO constituents were determined with Gas Chromatography/Mass Spectrometry (GC–MS) and Gas Chromatography/Flame Ionization Detector (GC-FID) and their antioxidant capacities were determined with the cupric reducing antioxidant capacity (CUPRAC) and 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) methods. The antimicrobial activity of EOs were tested against four pathogenic bacteria. Phenylpropanoids in anise (94.87%) and fennel (92.52%), oxygenated monoterpenes in dill (67.59%) and coriander (98.96%), monoterpene hydrocarbons in celery (75.42%), mono- (45.42%) and sesquiterpene- (43.25%) hydrocarbons in carrots, monoterpene hydrocarbon (34.30%) and aromatic hydrocarbons (32.92%) in cumin were the major compounds in the EOs. Anethole in anise and fennel, carotol in carrot, limonene in celery, carvone in dill, linalool in coriander, and cumin aldehyde in cumin were predominant compounds in these EOs. The high hydrocarbon content in cumin EO gave high CUPRAC activity (89.07 µmol Trolox g−1), and the moderate monoterpene hydrocarbon and oxygenated monoterpene content in dill EO resulted in higher DPPH activity (9.86 µmol Trolox g−1). The in vitro antibacterial activity of EOs against Bacillus cereus, Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli was evaluated using the agar diffusion method and the minimum bactericidal concentration was determined. Coriander, cumin and dill EOs showed inhibitory effect against all tested strains except P. aeruginosa. While fennel and celery EOs were effective against E. coli and B. cereus strains, respectively, anise and carrot EOs did not show any antibacterial effect against the tested bacteria. Hierarchical Cluster Analysis (HCA) produced four groups based on EO constituents of seven species. The potential adoption of the cultivated Apiaceae species for EO extraction could be beneficial for the wild species that are endangered by over collection and consumption.

Phytochemical screening and GC-FID identification of bioactive compounds in n-hexane, ethylacetate and methanol fractions of methanolic leaves extract of Azanza garckeana

Azanza garckeana is a tropical African plant commonly used for food and medicine. This study was aimed at evaluating the antioxidant, phytochemicals and the bioactive compounds present in n-hexane, ethylacetate and methanol fractions of the methanolic extract of Azanza garckeana leaves. Phytochemical screening and antioxidant assayed were carried out using standard methods, while bioactive compounds were analyzed using gas chromatography-flame ionization detector (GC-FID). The phytochemical compositions revealed considerable level of tannins and saponins with moderate concentration of flavonoids and steroids in the methanol fraction; whereas n-hexane fraction also showed considerable amount of tannins followed by saponins and a low concentration of steroids. However, ethylacetate fraction had the highest yield of tannins, steroids, and terpenoids which were significantly (p < 0.05) higher than methanolic fraction and n-hexane fraction respectively. The antioxidant activity of the methanolic crude extract of A. garckeana leaves showed that the % DPPH radical scavenging activity of the crude extract increased with decreased in concentration when compared with the standard antioxidant (ascorbic acid). The result of GC-FID analysis revealed the presence of nineteen constituents in n-hexane fraction, while ethylacetate and methanol fractions each have twenty constituents. This result showed that Azanza garckeana leaves contain health-promoting bioactive compounds with potent antioxidants.

Urinary biomonitoring of fuel ether oxygenates using a needle trap device packed with a novel molecularly imprinted polymer surface modified Zeolite Y

This study introduces an innovative needle trap device (NTD) featuring a molecularly imprinted polymer (MIP) surface-modified Zeolite Y. The developed NTD was integrated with gas chromatography-flame ionization detector (GC-FID) and employed for analysis of fuel ether oxygenates (methyl tert‑butyl ether, MTBE, ethyl tert‑butyl ether, ETBE, and tert‑butyl formate, TBF) in urine samples. To optimize the key experimental variables including extraction temperature, extraction time, salt concentration, and stirring speed, a central composite design-response surface methodology (CCD-RSM) was employed. The optimal values for extraction in the study were found to be 51.2 °C extraction temperature, 46.2 min extraction time, 27 % salt concentration, and 620 rpm stirring speed. Under the optimized conditions, the calibration curves demonstrated excellent linearity within the range of 0.1–100 μg L−1, with correlation coefficients (R2) exceeding 0.99. The limits of detection (LODs) for MTBE, ETBE, and TBF were obtained 0.06, 0.08, and 0.09 μg L−1, respectively. Moreover, the limits of quantification (LOQs) for MTBE, ETBE, and TBF were obtained 0.18, 0.24, and 0.27 μg L−1, respectively. The enrichment factor was also found to be in the range of 98–129.The NTD-GC-FID procedure demonstrated a high extraction efficiency, making it a promising tool for urinary biomonitoring of fuel ether oxygenates with improved sensitivity and selectivity compared to current methods.

Risk Assessments of Polycyclic Aromatic Hydrocarbons in the Surface Sediments of Drinking Water Sources in Ifite Ogwari, South-East Nigeria

ABSTRACT Surface water is the main source of drinking water in Ifite Ogwari, Anambra State, South-East Nigeria. In aquatic environments, sediment functions as both a source and a sink of polycyclic aromatic hydrocarbons (PAHs). To determine the level of pollution, health concerns to people and the environment, and potential sources of PAHs in the surface water sediments in Ifite Ogwari, sediment samples were collected from 9 surface water sources used for drinking by Ifite Ogwari people and were analyzed using a Gas Chromatography/Flame Ionization Detector (GC-FID). In all sediment samples, only 11 PAHs out of 16 United States Environmental Protection Agency (USEPA) priority PAHs were detected while 5 were below detectable limits. The concentration of benzo[a]anthracene was high but detected in only 2 sediment samples while fluoranthene has a relatively close concentration across all samples. Benzo[k]fluoranthene has the highest concentration compared to other PAHs in the samples while benzo[a]pyrene has the lowest concentration across all samples. Atammele sediment was analyzed as the most carcinogenic followed by Isiachala with concentrations of 84.23 ng/µL and 51.92 ng/µL respectively. Ube stream sediment has the lowest concentration of PAHs (11.74 ng/µL). Ecological risk of the PAHs revealed a sediment-to-sediment variation in the risk profile. Human health risk assessment depicts that hazard index and total cancer risk for adults and children ranged from 2.3E-07 - 2.57E-05 and 4.85E-07 - 5.43E-05 respectively. Pyrogenic activities are the main source of PAHs in the sediments. The results provide a guide for monitoring PAHs pollution and protecting drinking water sources.

Exploring volatile organic profiles of red pen inks based on gas-chromatography-flame ionization detection (GC-FID) and chemometric methods for forensic investigation purposes

Criminal cases involving questioned documents often cause the loss of a huge amount of money in a country. Red ballpoint pen inks found on threatening notes, or any official documents are potentially encountered by a forensic document examiner as questioned documents. Identifying sources of the questioned ink entries is paramount to revealing the authenticity or sources of the document. Despite the multitude of works being devoted to discriminating pen inks by their sources, very little is focused on the volatile fractions. In this study, the volatile compositional profiles of ten types of red ballpoint pen inks as acquired by gas chromatography-flame ionization detection (GC-FID) were studied using various multivariate exploratory tools. Scores plot of principal component analysis reveals that inter-pen brand variation is higher than the inter-pen type variation. Meanwhile, hierarchical clustering analysis showed that 6 of the 10 pen types and all five pen brands could be discriminated. In conclusion, volatile organic compositions of red pen inks are useful in classifying the pen inks by brands. The outcome of the study will provide vital insight into the potential of volatile organic profiles in discriminating red pen inks sold in Malaysia.

LAMA WAKTU PENGHENTIAN KONSUMSI SOJU TERHADAP KADAR ALKOHOL HATI, MORFOLOGI HATI, DAN GAMBARAN HEMATOLOGI TIKUS PUTIH

LAMA WAKTU PENGHENTIAN KONSUMSI SOJU TERHADAP KADAR ALKOHOL HATI, MORFOLOGI HATI, DAN GAMBARAN HEMATOLOGI TIKUS PUTIH