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Fulltext A case study of illicit preparation of antirheumatic analgesic with phenylbutazone as active ingredient

Chang ET, Lim BH

Med J Malaysia, 1989 Jun;44(2):160-6.
PMID: 2626126

The abuse of phenylbutazone among rheumatoid arthritis patients has recently become a subject of interest. Unscrupulous manufacturers take advantage of the miraculous analgesic property of phenylbutazone and deliberately add this toxic drug in their preparations without declaring its presence on the label. In a recent survey, many such illicit preparations were seized from Chinese medical halls in Johor and sent to the Department of Chemistry, Johor Bahru for analysis. Here a Gas Chromatograph Mass Selective Detector (GC-MSD) method was developed for the determination of phenylbutazone in illicit traditional preparations.

Matched MeSH terms: Gas Chromatography-Mass Spectrometry/methods*
Rapid identification of pork for halal authentication using the electronic nose and gas chromatography mass spectrometer with headspace analyzer

Nurjuliana M, Che Man YB, Mat Hashim D, Mohamed AK

Meat Sci, 2011 Aug;88(4):638-44.
PMID: 21420795 DOI: 10.1016/j.meatsci.2011.02.022

The volatile compounds of pork, other meats and meat products were studied using an electronic nose and gas chromatography mass spectrometer with headspace analyzer (GCMS-HS) for halal verification. The zNose™ was successfully employed for identification and differentiation of pork and pork sausages from beef, mutton and chicken meats and sausages which were achieved using a visual odor pattern called VaporPrint™, derived from the frequency of the surface acoustic wave (SAW) detector of the electronic nose. GCMS-HS was employed to separate and analyze the headspace gasses from samples into peaks corresponding to individual compounds for the purpose of identification. Principal component analysis (PCA) was applied for data interpretation. Analysis by PCA was able to cluster and discriminate pork from other types of meats and sausages. It was shown that PCA could provide a good separation of the samples with 67% of the total variance accounted by PC1.

Matched MeSH terms: Gas Chromatography-Mass Spectrometry/methods*
Chemometric techniques in oil classification from oil spill fingerprinting

Ismail A, Toriman ME, Juahir H, Kassim AM, Zain SM, Ahmad WKW, et al.

Mar Pollut Bull, 2016 Oct 15;111(1-2):339-346.
PMID: 27397593 DOI: 10.1016/j.marpolbul.2016.06.089

Extended use of GC-FID and GC-MS in oil spill fingerprinting and matching is significantly important for oil classification from the oil spill sources collected from various areas of Peninsular Malaysia and Sabah (East Malaysia). Oil spill fingerprinting from GC-FID and GC-MS coupled with chemometric techniques (discriminant analysis and principal component analysis) is used as a diagnostic tool to classify the types of oil polluting the water. Clustering and discrimination of oil spill compounds in the water from the actual site of oil spill events are divided into four groups viz. diesel, Heavy Fuel Oil (HFO), Mixture Oil containing Light Fuel Oil (MOLFO) and Waste Oil (WO) according to the similarity of their intrinsic chemical properties. Principal component analysis (PCA) demonstrates that diesel, HFO, MOLFO and WO are types of oil or oil products from complex oil mixtures with a total variance of 85.34% and are identified with various anthropogenic activities related to either intentional releasing of oil or accidental discharge of oil into the environment. Our results show that the use of chemometric techniques is significant in providing independent validation for classifying the types of spilled oil in the investigation of oil spill pollution in Malaysia. This, in consequence would result in cost and time saving in identification of the oil spill sources.

Matched MeSH terms: Gas Chromatography-Mass Spectrometry/methods*
Recent Modifications and Validation of QuEChERS-dSPE Coupled to LC-MS and GC-MS Instruments for Determination of Pesticide/Agrochemical Residues in Fruits and Vegetables: Review

Lawal A, Wong RCS, Tan GH, Abdulra'uf LB, Alsharif AMA

J Chromatogr Sci, 2018 Aug 01;56(7):656-669.
PMID: 29688338 DOI: 10.1093/chromsci/bmy032

Fruits and vegetables constitute a major type of food consumed daily apart from whole grains. Unfortunately, the residual deposits of pesticides in these products are becoming a major health concern for human consumption. Consequently, the outcome of the long-term accumulation of pesticide residues has posed many health issues to both humans and animals in the environment. However, the residues have previously been determined using conventionally known techniques, which include liquid-liquid extraction, solid-phase extraction (SPE) and the recently used liquid-phase microextraction techniques. Despite the positive technological effects of these methods, their limitations include; time-consuming, operational difficulty, use of toxic organic solvents, low selective property and expensive extraction setups, with shorter lifespan of instrumental performances. Thus, the potential and maximum use of these methods for pesticides residue determination has resulted in the urgent need for better techniques that will overcome the highlighted drawbacks. Alternatively, attention has been drawn recently towards the use of quick, easy, cheap, effective, rugged and safe technique (QuEChERS) coupled with dispersive solid-phase extraction (dSPE) to overcome the setback challenges experienced by the previous technologies. Conclusively, the reviewed QuEChERS-dSPE techniques and the recent cleanup modifications justifiably prove to be reliable for routine determination and monitoring the concentration levels of pesticide residues using advanced instruments such as high-performance liquid chromatography, liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry.

Matched MeSH terms: Gas Chromatography-Mass Spectrometry/methods*
Fulltext A study on volatile organic compounds emitted by in-vitro lung cancer cultured cells using gas sensor array and SPME-GCMS

Thriumani R, Zakaria A, Hashim YZH, Jeffree AI, Helmy KM, Kamarudin LM, et al.

BMC Cancer, 2018 04 02;18(1):362.
PMID: 29609557 DOI: 10.1186/s12885-018-4235-7

BACKGROUND: Volatile organic compounds (VOCs) emitted from exhaled breath from human bodies have been proven to be a useful source of information for early lung cancer diagnosis. To date, there are still arguable information on the production and origin of significant VOCs of cancer cells. Thus, this study aims to conduct in-vitro experiments involving related cell lines to verify the capability of VOCs in providing information of the cells.
METHOD: The performances of e-nose technology with different statistical methods to determine the best classifier were conducted and discussed. The gas sensor study has been complemented using solid phase micro-extraction-gas chromatography mass spectrometry. For this purpose, the lung cancer cells (A549 and Calu-3) and control cell lines, breast cancer cell (MCF7) and non-cancerous lung cell (WI38VA13) were cultured in growth medium.
RESULTS: This study successfully provided a list of possible volatile organic compounds that can be specific biomarkers for lung cancer, even at the 24th hour of cell growth. Also, the Linear Discriminant Analysis-based One versus All-Support Vector Machine classifier, is able to produce high performance in distinguishing lung cancer from breast cancer cells and normal lung cells.
CONCLUSION: The findings in this work conclude that the specific VOC released from the cancer cells can act as the odour signature and potentially to be used as non-invasive screening of lung cancer using gas array sensor devices.

Matched MeSH terms: Gas Chromatography-Mass Spectrometry*
Assessment of the phytochemical profiles of novel hop (Humulus lupulus L.) cultivars: A potential route to beer crafting

Yan D, Wong YF, Shellie RA, Marriott PJ, Whittock SP, Koutoulis A

Food Chem, 2019 Mar 01;275:15-23.
PMID: 30724181 DOI: 10.1016/j.foodchem.2018.09.082

This study investigated the volatile phytochemical diversity of 30 samples obtained from experimental hybrid and commercial H. lupulus L. plants. Essential oils distilled from these samples were analysed by high resolution gas chromatography coupled with accurate mass time-of-flight mass spectrometry (GC-accTOFMS). A total of 58 secondary metabolites, mainly comprising 18 esters, 6 monoterpene hydrocarbons, 2 oxygenated monoterpenes, 20 sesquiterpene hydrocarbons, 7 oxygenated sesquiterpenes, and 4 ketones, were positively or tentatively identified. A total of 24 metabolites were detected in all samples, but commercial cultivars (selected for brewing performance) had fewer compounds identified compared to experimental genotypes. Chemometrics analyses enabled distinct differentiation of experimental hybrids from commercial cultivars, discussed in terms of the different classes of compounds present in different genotypes. Differences among the mono- and sesquiterpenoids, appear to be related to either: i) the genetic origin of the plants; or ii) the processes of bioaccumulation of the identified secondary metabolites.

Matched MeSH terms: Gas Chromatography-Mass Spectrometry/methods
Production of gasoline range hydrocarbons from catalytic cracking of linoleic acid over various acidic zeolite catalysts

Gurdeep Singh HK, Yusup S, Quitain AT, Kida T, Sasaki M, Cheah KW, et al.

Environ Sci Pollut Res Int, 2019 Nov;26(33):34039-34046.
PMID: 30232774 DOI: 10.1007/s11356-018-3223-4

Employment of edible oils as alternative green fuel for vehicles had raised debates on the sustainability of food supply especially in the third-world countries. The non-edible oil obtained from the abundantly available rubber seeds could mitigate this issue and at the same time reduce the environmental impact. Therefore, this paper investigates the catalytic cracking reaction of a model compound named linoleic acid that is enormously present in the rubber seed oil. Batch-scale experiments were conducted using 8.8 mL Inconel batch reactor having a cyclic horizontal swing span of 2 cm with a frequency of 60 cycles per minute at 450 °C under atmospheric condition for 90 min. The performance of HZSM-5, HBeta, HFerrierite, HMordenite and HY catalysts was tested for their efficiency in favouring gasoline range hydrocarbons. The compounds present in the organic liquid product were then analysed using GC-MS and classified based on PIONA which stands for paraffin, isoparaffin, olefin, naphthenes and aromatics respectively. The results obtained show that HZSM-5 catalyst favoured gasoline range hydrocarbons that were rich in aromatics compounds and promoted the production of desired isoparaffin. It also gave a higher cracking activity; however, large gaseous as by-products were produced at the same time.

Matched MeSH terms: Gas Chromatography-Mass Spectrometry/methods
Simple, rapid and sensitive assay method for simultaneous quantification of urinary nicotine and cotinine using gas chromatography-mass spectrometry

Man CN, Gam LH, Ismail S, Lajis R, Awang R

J Chromatogr B Analyt Technol Biomed Life Sci, 2006 Dec 5;844(2):322-7.
PMID: 16908224

Nicotine is a major addictive compound in cigarette. Its smoke is rapidly and extensively metabolized to several metabolites in human. Cotinine as a major metabolite of nicotine is commonly used as a biomarker to determine active and passive smokers. Cotinine has a longer half-life ( approximately 20 h) compared to nicotine ( approximately 2h). A simple, sensitive, rapid and high throughput GC-MS method was developed for simultaneous quantification of urinary nicotine and cotinine in passive and active smokers. In the sample preparation method, the analytes and internal standard were first basified and followed by liquid-liquid extraction. Upon completion, anhydrous sodium sulphate was added to the solvent mixture to trap moistures. The clear extract obtained was directly injected into GC-MS, operating under selective ion monitoring (SIM) mode. Calibration curves in the range of 0.5-5000 ng/mL of the analytes in urine matrix were established with linear correlation coefficients (r(2)) greater than 0.997. The limit of detection for both nicotine and cotinine were 0.20 ng/mL. The mean recoveries for nicotine and cotinine were 93.0 and 100.4%, respectively. The within- and between-assay accuracies were between 2.1 and 7.9% for nicotine and between 0.7 and 11.1% for cotinine. Within- and between-assay precisions of 3.3-9.5% for nicotine and 3.4-9.8% for cotinine were also achieved. The method can be used in routine assessment and monitoring of active smoking and exposure to environmental tobacco smoke. The applicability of the assay was demonstrated in a small-scale comparison study between smokers and non-smokers.

Matched MeSH terms: Gas Chromatography-Mass Spectrometry/methods*
Determination of hair nicotine by gas chromatography-mass spectrometry

Man CN, Ismail S, Harn GL, Lajis R, Awang R

J Chromatogr B Analyt Technol Biomed Life Sci, 2009 Jan 15;877(3):339-42.
PMID: 19109080 DOI: 10.1016/j.jchromb.2008.12.014

Hair nicotine is a known biomarker for monitoring long-term environmental tobacco smoke (ETS) exposure and smoking status. In general, hair nicotine assay involves alkaline digestion, extraction and instrumental analysis. The gas chromatography-mass spectrometry (GC-MS) assay currently developed has shown to be of high throughput with average approximately 100 hair samples being extracted and analyzed per day. This was achieved through simplified extraction procedure and shortened GC analysis time. The extraction was improved by using small volume (0.4 mL) of organic solvent that does not require further evaporation and salting steps prior to GC-MS analysis. Furthermore, the amount of hair utilized in the extraction was very little (5 mg) while the sensitivity and selectivity of the assay is equal, if not better than other established methods. The linearity of the assay (r(2)>0.995), limit of quantitation (0.04 ng/mg hair), within- and between-assays accuracies and precisions (<11.4%) and mean recovery (92.6%) were within the acceptable range.

Matched MeSH terms: Gas Chromatography-Mass Spectrometry*
Gas Chromatography-Mass Spectrometry (GC-MS) Analysis of Scaphium Affine Seed Extract and Assessment of Its Anti-hemorrhoidal Efficacy

Abbas SA, Khan A, Fatima M, Kalusalingam A, Kanakal MM, Inamdar SK, et al.

Antiinflamm Antiallergy Agents Med Chem, 2024;23(2):118-128.
PMID: 38357954 DOI: 10.2174/0118715230285370240131111539

BACKGROUND: Seeds of plant Scaphium affine are traditionally used by the healers of "India" for the treatment of piles.
OBJECTIVES: The primary objective of the study was to assess the anti-hemorrhoidal potential of the ethanolic seed extract of Scaphium affine.
METHODS: After the soxhlet extraction method, the seed extract from Scaphium affine was first submitted to phytochemical standardization and then GC-MS analysis. Rats were given Croton oil and Jatropha oil to develop hemorrhoids, and Scaphium affine seed extract (ESA) was administered orally for 5 days and 3 days, respectively, at doses of 1000 and 500 mg/kg. The Rectoanal coefficient (RAC) was calculated as an inflammatory marker. The hemorrhoidal tissues were also subjected to cytokine profiling, biochemical estimation and histopathology.
RESULTS: ESA demonstrated the presence of flavonoids, saponins, phytosterols, phenols, and tannins. GCMS analysis elucidated the presence of hexadecanoic acid 2 hydroxy -1,3 propane diyl ester,9 Octadecanoic acid ethyl ester, Cyclohexane 1,4 di methyl cis, Farnesol isomer,1, E-11, Z-13 octa decatriene, Stigmasterol, N-(5 ethyl -1,3,4-thiadiazol-yl) benzamide, N, N Dinitro 1,3,5,7 tetraza bicyclo 93,3,1) as major phytoconstituents. The results depicted more potent anti-hemorrhoidal activity of ESA at 1000 mg/kg, p.o., which was evident through a decrease in RAC. A significant decline in the levels of IL-1β, IL-6, and TNF-α expression was observed, along with the restoration of altered antioxidants and enzymes. Histopathological analysis confirmed the tissue recovery as it revealed minimal inflammation and decreased dilated blood vessels in treated animals.
CONCLUSION: Based on the results it can be concluded that seeds of Scaphium affine showed significant anti-hemorrhoid agents which may be attributed to their anti-inflammatory and anti-oxidant potential due to the presence of certain phytoconstituents in it. The study also supports the traditional use of seeds of Scaphium affine for the first time in the treatment of hemorrhoids.

Matched MeSH terms: Gas Chromatography-Mass Spectrometry*
Fulltext Investigation of Antioxidative and Anticancer Potentials of Streptomyces sp. MUM256 Isolated from Malaysia Mangrove Soil

Tan LT, Ser HL, Yin WF, Chan KG, Lee LH, Goh BH

Front Microbiol, 2015;6:1316.
PMID: 26635777 DOI: 10.3389/fmicb.2015.01316

A Streptomyces strain, MUM256 was isolated from Tanjung Lumpur mangrove soil in Malaysia. Characterization of the strain showed that it has properties consistent with those of the members of the genus Streptomyces. In order to explore the potential bioactivities, extract of the fermented broth culture of MUM256 was prepared with organic solvent extraction method. DPPH and SOD activity were utilized to examine the antioxidant capacity and the results have revealed the potency of MUM256 in superoxide anion scavenging activity in dose-dependent manner. The cytotoxicity of MUM256 extract was determined using cell viability assay against 8 different panels of human cancer cell lines. Among all the tested cancer cells, HCT116 was the most sensitive toward the extract treatment. At the highest concentration of tested extract, the result showed 2.3-, 2.0-, and 1.8-folds higher inhibitory effect against HCT116, HT29, and Caco-2 respectively when compared to normal cell line. This result has demonstrated that MUM256 extract was selectively cytotoxic toward colon cancer cell lines. In order to determine the constituents responsible for its bioactivities, the extract was then subjected to chemical analysis using GC-MS. The analysis resulted in the identification of chemical constituents including phenolic and pyrrolopyrazine compounds which may responsible for antioxidant and anticancer activities observed. Based on the findings of this study, the presence of bioactive constituents in MUM256 extract could be a potential source for the development of antioxidative and chemopreventive agents.

Matched MeSH terms: Gas Chromatography-Mass Spectrometry
Novel solid-phase membrane tip extraction and gas chromatography with mass spectrometry methods for the rapid analysis of triazine herbicides in real waters

Sanagi MM, Muhammad SS, Hussain I, Ibrahim WA, Ali I

J Sep Sci, 2015 Feb;38(3):433-8.
PMID: 25421899 DOI: 10.1002/jssc.201400912

Novel, fast, selective, eco-friendly and reproducible solid-phase membrane tip extraction and gas chromatography with mass spectrometry methods were developed and validated for the analysis of triazine herbicides (atrazine and secbumeton) in stream and lake waters. The retention times of atrazine and secbumeton were 7.48 and 8.51 min. The solid-phase membrane tip extraction was carried out in semiautomated dynamic mode on multiwall carbon nanotubes enclosed in a cone-shaped polypropylene membrane cartridge. Acetone and methanol were found as the best preconditioning and desorption solvents, respectively. The extraction and desorption times for these herbicides were 15.0 and 10.0 min, respectively. The percentage recoveries of atrazine and secbumeton were 88.0 and 99.0%. The linearity range was 0.50-80.0 μg/L (r(2) > 0.994), with detection limits (<0.47 μg/L, S/N = 3) and good reproducibility (<8.0%). The ease of operation, eco-friendly nature, and low cost of solid-phase membrane tip extraction made these methods novel. The Solid-phase membrane tip extraction method was optimized by considering the effect of extraction time, desorbing solvents and time.

Matched MeSH terms: Gas Chromatography-Mass Spectrometry
Chemical compositions and antimicrobial activity of the essential oils of Piper abbreviatum, P. erecticaule and P. lanatum (Piperaceae)

Wan Salleh WM, Ahmad F, Yen KH

Nat Prod Commun, 2014 Dec;9(12):1795-8.
PMID: 25632488

The study was designed to examine the chemical composition and antimicrobial activities of essential oils extracted from the aerial parts of three Piper species: Piper abbreviatum, P. erecticaule and P. lanatum, all from Malaysia. GC and GC/MS analysis showed qualitative and quantitative differences between these oils. GC and GC-MS analysis of P. abbreviatum, P. erecticaule and P. lanatum oils resulted in the identification of 33, 35 and 39 components, representing 70.5%, 63.4% and 78.2% of the components, respectively. The major components of P. abbreviatum oil were spathulenol (11.2%), (E)-nerolidol (8.5%) and β-caryophyllene (7.8%), whereas P. erecticaule oil mainly contained β-caryophyllene (5.7%) and spathulenol (5.1%). Borneol (7.5%), β-caryophyllene (6.6%) and α-amorphene (5.6%) were the most abundant components in P. lanatum oil. Antimicrobial activity was carried out using disc diffusion and broth micro-dilution method against nine microorganisms. All of the essential oils displayed weak activity towards Gram-positive bacteria with MIC values in the range 250-500 μg/mL. P. erecticaule oil showed the best activity on Aspergillus niger (MIC 31.3 μg/mL), followed by P. lanatum oil (MIC 62.5 μg/mL). This study demonstrated that the essential oils have potential as antimicrobial agents and may be useful in the pharmaceutical and cosmetics industries.

Matched MeSH terms: Gas Chromatography-Mass Spectrometry
Modeling of crude oil biodegradation using two phase partitioning bioreactor

Fakhru'l-Razi A, Peyda M, Ab Karim Ghani WA, Abidin ZZ, Zakaria MP, Moeini H

Biotechnol Prog, 2014 Jul-Aug;30(4):797-805.
PMID: 24692323 DOI: 10.1002/btpr.1911

In this work, crude oil biodegradation has been optimized in a solid-liquid two phase partitioning bioreactor (TPPB) by applying a response surface methodology based d-optimal design. Three key factors including phase ratio, substrate concentration in solid organic phase, and sodium chloride concentration in aqueous phase were taken as independent variables, while the efficiency of the biodegradation of absorbed crude oil on polymer beads was considered to be the dependent variable. Commercial thermoplastic polyurethane (Desmopan®) was used as the solid phase in the TPPB. The designed experiments were carried out batch wise using a mixed acclimatized bacterial consortium. Optimum combinations of key factors with a statistically significant cubic model were used to maximize biodegradation in the TPPB. The validity of the model was successfully verified by the good agreement between the model-predicted and experimental results. When applying the optimum parameters, gas chromatography-mass spectrometry showed a significant reduction in n-alkanes and low molecular weight polycyclic aromatic hydrocarbons. This consequently highlights the practical applicability of TPPB in crude oil biodegradation.

Matched MeSH terms: Gas Chromatography-Mass Spectrometry
Potential of a white-rot fungus Pleurotus eryngii F032 for degradation and transformation of fluorene

Hadibarata T, Kristanti RA

Fungal Biol, 2014 Feb;118(2):222-7.
PMID: 24528643 DOI: 10.1016/j.funbio.2013.11.013

The white-rot fungus Pleurotus eryngii F032 showed the capability to degrade a three fused-ring aromatic hydrocarbons fluorene. The elimination of fluorene through sorption was also investigated. Enzyme production is accompanied by an increase in biomass of P. eryngii F032 during degradation process. The fungus totally degraded fluorine within 23 d at 10-mg l(-1) solution. Fluorene degradation was affected with initial fluorene concentrations. The highest enzyme activity was shown by laccase in the 10-mg l(-1) culture after 30 d of incubation (1620 U l(-1)). Few activities of enzymes were observed in the fungal cell at the varying concentration of fluorene. Three metabolic were detected and separated in ethylacetate extract, after isolated by column chromatography. The metabolites, 9-fluorenone, phthalic acid, and benzoic acid were identified using UV-vis spectrophotometer and gas chromatography-mass spectrometry (GC-MS). The results show the presence of a complex mechanism for the regulation of fluorene-degrading enzymes.

Matched MeSH terms: Gas Chromatography-Mass Spectrometry
The effects of physical refining on the formation of 3-monochloropropane-1,2-diol esters in relation to palm oil minor components

Zulkurnain M, Lai OM, Latip RA, Nehdi IA, Ling TC, Tan CP

Food Chem, 2012 Nov 15;135(2):799-805.
PMID: 22868161 DOI: 10.1016/j.foodchem.2012.04.144

The formation of 3-monochloropropane-1,2-diol (3-MCPD) esters in refined palm oil during deodorisation is attributed to the intrinsic composition of crude palm oil. Utilising D-optimal design, the effects of the degumming and bleaching processes on the reduction in 3-MCPD ester formation in refined palm oil from poor-quality crude palm oil were studied relative to the palm oil minor components that are likely to be their precursors. Water degumming remarkably reduced 3-MCPD ester formation by up to 84%, from 9.79 mg/kg to 1.55 mg/kg. Bleaching with synthetic magnesium silicate caused a further 10% reduction, to 0.487 mg/kg. The reduction in 3-MCPD ester formation could be due to the removal of related precursors prior to the deodorisation step. The phosphorus content of bleached palm oil showed a significant correlation with 3-MCPD ester formation.

Matched MeSH terms: Gas Chromatography-Mass Spectrometry
Characterisation of calamansi (Citrus microcarpa). Part II: volatiles, physicochemical properties and non-volatiles in the juice

Cheong MW, Zhu D, Sng J, Liu SQ, Zhou W, Curran P, et al.

Food Chem, 2012 Sep 15;134(2):696-703.
PMID: 23107680 DOI: 10.1016/j.foodchem.2012.02.139

Calamansi juices from three countries (Malaysia, the Philippines and Vietnam) were characterised through measuring volatiles, physicochemical properties and non-volatiles (sugars, organic acids and phenolic acids). The volatile components of manually squeezed calamansi juices were extracted using dichloromethane and headspace solid-phase microextraction, and then analysed using gas chromatography-mass spectrometry/flame ionisation detector, respectively. A total of 60 volatile compounds were identified. The results indicated that the Vietnam calamansi juice contained the highest amount of volatiles. Two principal components obtained from principal component analysis (PCA) represented 89.65% of the cumulative total variations of the volatiles. Among the non-volatile components, these three calamansi juices could be, to some extent, differentiated according to fructose and glucose concentrations. Hence, this study of calamansi juices could lead to a better understanding of calamansi fruits.

Matched MeSH terms: Gas Chromatography-Mass Spectrometry
Fulltext Synthesis, characterization and fluorescent property evaluation of 1,3,5-triaryl-2-pyrazolines

Hasan A, Abbas A, Akhtar MN

Molecules, 2011 Sep 13;16(9):7789-802.
PMID: 22143543 DOI: 10.3390/molecules16097789

A series of 1,3,5-triaryl-2-pyrazolines was synthesized by dissolving the corresponding 4-alkoxychalcones in glacial acetic acid containing a few drops of concentrated hydrochloric acid. This step was followed by the addition of (3,4-dimethylphenyl) hydrazaine hydrochloride. Finally the target compounds were precipitated by pouring the reaction mixture onto crushed ice. The structures of the synthesized compounds were established by physicochemical and spectroscopic methods. The 1,3,5-triaryl-2-pyrazolines bearing homologous alkoxy groups were found to possess fluorescence properties in the blue region of the visible spectrum when irradiated with ultraviolet radiation. The fluorescent behavior of these compounds was studied by UV-Vis and emission spectroscopy, performed at room temperature.

Matched MeSH terms: Gas Chromatography-Mass Spectrometry
Sludge palm oil as a renewable raw material for biodiesel production by two-step processes

Hayyan A, Alam MZ, Mirghani ME, Kabbashi NA, Hakimi NI, Siran YM, et al.

Bioresour Technol, 2010 Oct;101(20):7804-11.
PMID: 20541401 DOI: 10.1016/j.biortech.2010.05.045

In this study, biodiesel was produced from sludge palm oil (SPO) using tolune-4-sulfonic monohydrate acid (PTSA) as an acid catalyst in different dosages in the presence of methanol to convert free fatty acid (FFA) to fatty acid methyl ester (FAME), followed by a transesterification process using an alkaline catalyst. In the first step, acid catalyzed esterification reduced the high FFA content of SPO to less than 2% with the different dosages of PTSA. The optimum conditions for pretreatment process by esterification were 0.75% (w/w) dosage of PTSA to SPO, 10:1 M ratio, 60 °C temperature, 60 min reaction time and 400 rpm stirrer speed. The highest yield of biodiesel after transesterification and purification processes was 76.62% with 0.07% FFA and 96% ester content. The biodiesel produced was favorable as compared to EN 14214 and ASTM 6751 standard. This study shows a potential exploitation of SPO as a new feedstock for the production of biodiesel.

Matched MeSH terms: Gas Chromatography-Mass Spectrometry
[Over one hundred year sedimentary record of polycyclic aromatic hydrocarbons in the Andaman Sea, Malaysia]

Wu YL, Wang XH, Li YY, Hong HS, Li HY, Yin MD

Huan Jing Ke Xue, 2009 Sep 15;30(9):2512-9.
PMID: 19927796

Polycyclic aromatic hydrocarbons (PAHs) in a sediment core collected from Langkawi Island of the Andaman Sea, Malaysia were determined by GC/MS, the vertical variations of concentration and distributions of PAHs were investigated. In combining with 210Pb-dating, the PAHs sedimentary record in the last 100 years was reconstructed and their possible sources were also discussed. The sigmaPAH concentration ranged from 13.2-60.1 ng x g(-1) in the whole sedimentary section (0-56 cm) with the dominant compounds of phenanthrene, naphthalene and perylene. The sediments contaminated to a lesser extent comparing with the surrounding waters. Before the 1920s, the concentrations of PAHs were considered to be the background level, which was implied from the natural inputs. The historical records of PAHs in the core showed that two distinct peaks which represented the input time of 1960s and 1980s, respectively, inferred that there were some relatively dramatically land-based inputs, and human activities leaded a clear impact to these waters during these periods. Furthermore, PAHs diagnostic ratios indicated that PAHs in the core sediments were mainly of pyrolytic origin (combustion), accompanied with minor petroleum origin. These were related with agriculture, industry, ocean import and export, and shipping activities in the surrounding regions. Meanwhile as the vital communication line, the marine transportation of the Strait of Malacca had influenced the environmental quality of the Andaman Sea. Meanwhile, based on the sedimentary record, PAHs concentrations were found to correlate positively with humanism activities and socioeconomic development (Gross Domestic Production) in the surrounding regions.

Matched MeSH terms: Gas Chromatography-Mass Spectrometry

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