This study reports the concentrations and congener partners of polychlorinated biphenyls (PCBs) in commercially available paints. Polycyclic-type pigments containing dioxazine violet (pigment violet (PV) 23, PV37) and diketopyrrolopyrrole (PR254, PR255) were found to contain PCB-56, PCB-77, PCB-40, PCB-5, and PCB-12, and PCB-6, PCB-13, and PCB-15, respectively, as major congeners. Dioxazine violet is contaminated with by-products during synthesis from o-dichlorobenzene, which is used as a solvent during synthesis, and diketopyrrolopyrrole is contaminated with by-products during synthesis from p-chlorobenzonitrile. The concentration of PCBs in paint containing PV23 or PV37 was 0.050-29 mg/kg, and toxic equivalency (TEQ) values ranged 1.1-160 pg-TEQ/g. The concentration of PCBs in paint containing PR254 or PR255 was 0.0019-2.4 mg/kg. Naphthol AS is an azo-type pigment, and PCB-52 was detected in paint containing pigment red (PR) 9 with 2,5-dichloroaniline as its source. PCB-146, PCB-149, and PCB-153 were identified from paint containing PR112 produced from 2,4,5-trichloroaniline, as major congeners. These congeners have chlorine positions similar to aniline, indicating that these congeners are by-products obtained during the synthesis of pigments. The concentrations of PCBs in paints containing PR9 and PR112 were 0.0042-0.43 and 0.0044-3.8 mg/kg, respectively. The corresponding TEQ for PR112 was 0.0039-8.6 pg-TEQ/g.
Matched MeSH terms: Gas Chromatography-Mass Spectrometry
Agricultural wastewater that produces color are of environmental and health concern as colored effluent can produce toxic and carcinogenic by-products. From this study, batch culture optimization using response surface methods indicated that the fungus isolated from the pineapple solid waste, Curvularia clavata was able to decolorize sterile palm oil mill effluent (POME) which is mainly associated with polyphenol and lignin. Results showed successful decolorization of POME up to 80 % (initial ADMI [American Dye Manufacturing Index] of 3,793) with 54 % contributed by biosorption and 46 % by biodegradation after 5 days of treatment. Analysis using HPLC and GC-MS showed the degradation of color causing compound such as 3-methoxyphenyl isothiocynate and the production of new metabolites. Ecotoxicity test indicated that the decolorized effluent is safe for discharge. To determine the longevity of the fungus for a prolonged decolorization period, sequential batch decolorization studies were carried out. The results showed that lignin peroxidase and laccase were the main ligninolytic enzymes involved in the degradation of color. Carboxymethyl cellulase (CMCase) and xylanase activities were also detected suggesting possible roles of the enzymes in promoting growth of the fungus which consequently contributed to improved decolorization of POME. In conclusion, the ability of C. clavata in treating color of POME indicated that C. clavata is of potential use for decolorization and degradation of agricultural wastewater containing polyphenolic compounds.
Matched MeSH terms: Gas Chromatography-Mass Spectrometry
Three short sediment cores from inner continental shelf of the southern South China Sea (5-50 km) off Terengganu were analyzed for lipid contents (i.e., homologous aliphatic compounds and sterols) using gas chromatography-mass spectrometry. The concentrations of the total aliphatic hydrocarbons (TAHs) ranged from 0.152 to 6.91 μg/g dry weight. The n-alkane distribution was from nC₁₃ to nC₃₆, with a carbon preference index (CPI₁₃₋₃₅) from 1.08 to 4.28 and a carbon number maximum (Cmax), depending on a sample, at 31 or 18. In addition, a strong odd-to-even carbon number predominance was observed in nC₂₅-nC₃₅ range. The distribution of the n-alkanoic acids and n-alkanols in all samples exhibited an even-to-odd carbon number predominance and ranged from C₁₀ to C₂₆ and from C₁₂ to C₃₄, respectively. The n-alkanols were dominated by the long-chain homologs with Cmax at 22; on the other hand, the n-alkanoic acid distributions showed a predominance of short-chain homologs with a Cmax at 16. The total sterol concentrations ranged from 0.41 to 3.57 μg/g dry weight. Cholesterol was most abundant at the offshore stations, whereas sitosterol was dominant at near-shore station. Pentacyclic triterpenoids such as friedelin and taraxerol α- and β-amyrins, which are known biomarkers for higher plants, were detected at all stations with a dilution trend offshore. In conclusion, the marine sediments off southern Terengganu can still be considered uncontaminated, where the compound sources are biogenic from terrestrial plants superimposed with a marine productivity input.
Matched MeSH terms: Gas Chromatography-Mass Spectrometry
Produced water or oilfield wastewater is the largest volume ofa waste stream associated with oil and gas production. The aim of this study was to investigate the biological pretreatment of synthetic and real produced water in a sequencing batch reactor (SBR) to remove hydrocarbon compounds. The SBR was inoculated with isolated tropical halophilic microorganisms capable of degrading crude oil. A total sequence of 24 h (60 min filling phase; 21 h aeration; 60 min settling and 60 min decant phase) was employed and studied. Synthetic produced water was treated with various organic loading rates (OLR) (0.9 kg COD m(-3) d(-1), 1.8 kg COD m(-3) d(-1) and 3.6 kg COD m(-3) d(-1)) and different total dissolved solids (TDS) concentration (35,000 mg L(-1), 100,000 mg L(-1), 150,000 mg L(-1), 200,000 mg L(-1) and 250,000 mg L(-1)). It was found that with an OLR of 0.9 kg COD m(-3) d(-1) and 1.8 kg COD m(-3) d(-1), average oil and grease (O&G) concentrations in the effluent were 7 mg L(-1) and 12 mg L(-1), respectively. At TDS concentration of 35,000 mg L(-1) and at an OLR of 1.8 kg COD m(-3)d(-1), COD and O&G removal efficiencies were more than 90%. However, with increase in salt content to 250,000 mg L(-1), COD and O&G removal efficiencies decreased to 74% and 63%, respectively. The results of biological treatment of real produced water showed that the removal rates of the main pollutants of wastewater, such as COD, TOC and O&G, were above 81%, 83%, and 85%, respectively.
Matched MeSH terms: Gas Chromatography-Mass Spectrometry
A method has been developed for the determination of trace levels of alpha-endosulfan, beta-endosulfan, endosulfan sulfate, and endosulfan diol in rat plasma and tissue samples. Endosulfan and its metabolites in the plasma samples were extracted with solid-phase extraction Chromabond-end-capped C18 cartridges and analyzed by a Shimadzu QP-5050A gas chromatograph-mass spectrometer (GCMS) with quadrupole detector in selected-ion-monitoring mode. The analysis of endosulfan and its metabolites in liver and kidney samples involved solvent extraction, Florisil solid-phase-extraction cleanup, and quantitation by GCMS. Recovery experiments for the plasma and tissue samples were conducted over concentration ranges of 10-100 ng mL(-1) and 100-1000 ng mL(-1), respectively. The method was applied to the analysis of trace levels of endosulfan and its metabolites in plasma and tissue samples collected from an animal study. Trace levels of alpha-endosulfan and beta-endosulfan in the ranges of undetectable to 3.11 microg g(-1) and undetectable to 1.19 microg g(-1), respectively, were detected in the kidney samples, whereas trace levels of endosulfan sulfate in the range of 0.02-0.22 microg g(-1) were detected in the liver samples of rats. Neither endosulfan nor its metabolites was detected in any of the plasma samples.
Matched MeSH terms: Gas Chromatography-Mass Spectrometry
Nowadays, microplastic pollution is one of the globally urgent concerns as a result of discharging plastic products into the atmosphere, aquatic and soil environments. Microplastics have average size of less than 5 mm, are non-biodegradable, accumulative, and highly persistent substances. Thousands of tons of microplastics are still accumulated in various environments, posing an enormous threat to human health and living creatures. Here, we review the occurrence and analytical methods, and impact of microplastics in the environments including soil, aquatic media, and atmosphere. Analytical methods including visual observation, Fourier-transform infrared spectroscopy, Raman spectroscopy, scanning electron microscopy, and pyrolysis-gas chromatography-mass spectrometry were evaluated. We elucidated the environmental and human health impacts of microplastics with emphasis on life malfunction, immune disruption, neurotoxicity, diseases and other tangible health risks. This review also found some shortages of analytical equivalence and/or standardization, inconsistence in sampling collection and limited knowledge of microplastic toxicity. It is hopeful that the present work not only affords a more insight into the potential dangers of microplastics on human health but also urges future researches to establish new standardizations in analytical methods.
Matched MeSH terms: Gas Chromatography-Mass Spectrometry
The study aimed to investigate the phytochemical contents, antioxidant and antiproliferative activity of 80% methanol extract of Lepidozia borneensis. The total phenolic and total flavonoid contents were analysed using Folin-Ciocalteu and aluminium chloride colorimetric methods. Antioxidant properties were evaluated by using FRAP, ABTS, and DPPH assays while the effects of L. borneensis on the proliferation of MCF-7 cell line were evaluated by using MTT assay. The results showed that the total phenolic and flavonoid contents were 12.42 ± 0.47 mg GAE/g and 9.36 ± 1.29 mg CE/g, respectively. The GC-MS analysis revealed the presence of at least 35 compounds. The extract was found to induce cytotoxicity against MCF-7 cell line with IC50 value of 47.33 ± 7.37 µg/mL. Cell cycle analysis showed that the extract induced significant arrest at G0/G1 at 24 hours of treatment. After 72 hours of treatment, the proportion of cells in G0/G1 and G2-M phases had decreased significantly as compared to their control. Apoptosis occurred during the first 24 hours and significantly increased to 30.8% after 72 hours of treatment. No activation of caspase 3 was observed. These findings suggest that L. borneensis extract has the potential as natural antioxidant and anticancer agents.
Matched MeSH terms: Gas Chromatography-Mass Spectrometry
We investigated the effect of different solvents (ethyl acetate, methanol, acetone, and chloroform) on the extraction of phytoconstituents from Lantana camara leaves and their antioxidant and antibacterial activities. Further, GC-MS analysis was carried out to identify the bioactive chemical constituents occurring in the active extract. The results revealed the presence of various phytocompounds in the extracts. The methanol solvent recovered higher extractable compounds (14.4% of yield) and contained the highest phenolic (92.8 mg GAE/g) and flavonoid (26.5 mg RE/g) content. DPPH radical scavenging assay showed the IC50 value of 165, 200, 245, and 440 μg/mL for methanol, ethyl acetate, acetone, and chloroform extracts, respectively. The hydroxyl scavenging activity test showed the IC50 value of 110, 240, 300, and 510 μg/mL for methanol, ethyl acetate, acetone, and chloroform extracts, respectively. Gram negative bacterial pathogens (E. coli and K. pneumoniae) were more susceptible to all extracts compared to Gram positive bacteria (M. luteus, B. subtilis, and S. aureus). Methanol extract had the highest inhibition activity against all the tested microbes. Moreover, methanolic extract of L. camara contained 32 bioactive components as revealed by GC-MS study. The identified major compounds included hexadecanoic acid (5.197%), phytol (4.528%), caryophyllene oxide (4.605%), and 9,12,15-octadecatrienoic acid, methyl ester, (Z,Z,Z)- (3.751%).
Matched MeSH terms: Gas Chromatography-Mass Spectrometry
The plant Typhonium flagelliforme, commonly known as "rodent tuber" in Malaysia, is often used as a health supplement and traditional remedy for alternative cancer therapies, including leukemia. This study aimed to evaluate in vitro anti-leukemic activity of dichloromethane extract/fraction number 7 (DCM/F7) from T. flagelliforme tuber on human T4 lymphoblastoid (CEMss) cell line. The DCM extract of tuber has been fractionated by column chromatography. The obtained fractions were evaluated for its cytotoxicity toward CEMss cells as well as human primary blood lymphocytes (PBLs). Assessment of apoptosis produced by the most active fraction was evaluated by various microscopic techniques and further confirmation of apoptosis was done by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. Phytochemical screening was done by gas chromatography-mass spectrometry (GC-MS). The results shows that 7 out of 12 fractions showed significant cytotoxicity against the selected cell line CEMss, in which fractions DCM/F7, DCM/F11 and DCM/F12 showed exceptional activity with 3, 5 and 6.2 μg ml(-1), respectively. Further studies in the non-cancerous PBL exhibited significant selectivity of DCM/F7 compared to other fractions. Cytological observations showed chromatin condensation, cell shrinkage, abnormalities of cristae, membrane blebbing, cytoplasmic extrusions and formation of apoptotic bodies as confirmed collectively by double-staining of acridine orange (AO)/propidium iodide (PI), SEM and TEM. In addition, DCM/F7 has increased the cellular DNA breaks on treated cells. GC-MS revealed that DCM/F7 contains linoleic acid, hexadecanoic acid and 9-hexadecanoic acid. The present results indicate that T. flagelliforme possess a valuable anti-leukemic effect and was able to produce distinctive morphological features of cell death that corresponds to apoptosis.
Matched MeSH terms: Gas Chromatography-Mass Spectrometry
The Nigella sativa L. popularly referred to as black seeds are widely used as a form of traditional nutrition and medicine. N. sativa seeds were used for the extraction of their oil by way of supercritical fluid extraction (SFE) and cold press (CP) to determine the physicochemical properties, antioxidant activity, and thermal behavior. The GC-MS results showed the primary constituents in the Nigella sativa oil (NSO) were Caryophyllene (17.47%) followed by thymoquinone (TQ) (11.80%), 1,4-Cyclohexadiene (7.17%), longifolene (3.5%), and carvacrol (1.82%). The concentration of TQ was found to be 6.63 mg/mL for oil extracted using SFE and 1.56 mg/mL for oil extracted by CP method. The antioxidant activity measured by DPPH and the IC50 was 1.58 mg/mL and 2.30 mg/mL for SFE oil and cold pressed oil, respectively. The ferric reducing/antioxidant power (FRAP) activity for SFE oil and CP oil was 538.67 mmol/100 mL and 329.00 mmol/100 mL, respectively. The total phenolic content (TPC) of SFE oil was 160.51 mg/100 mL and 94.40 mg/100 mL for CP oil presented as gallic acid equivalents (GAE). This research showed that a high level of natural antioxidants could be derived from NSO extracted by SFE.
Matched MeSH terms: Gas Chromatography-Mass Spectrometry
Breast cancer is among the most commonly diagnosed cancer and the leading cause of cancer-related death among women globally. Malaysia is a country that is rich in medicinal plant species. Hence, this research aims to explore the secondary metabolites, antioxidant, and antiproliferative activities of Dioscorea bulbifera leaf collected from Endau Rompin, Johor, Malaysia. Antioxidant activity was assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) assays, while the cytotoxicity of D. bulbifera on MDA-MB-231 and MCF-7 breast cancer cell lines was tested using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Cell cycle analysis and apoptosis were assessed using flow cytometry analysis. Phytochemical profiling was conducted using gas chromatography-mass spectrometry (GC-MS). Results showed that methanol extract had the highest antioxidant activity in DPPH, FRAP, and ABTS assays, followed by ethyl acetate and hexane extracts. D. bulbifera tested against MDA-MB-231 and MCF-7 cell lines showed a pronounced cytotoxic effect with IC50 values of 8.96 μg/mL, 6.88 μg/mL, and 3.27 μg/mL in MCF-7 and 14.29 μg/mL, 11.86 μg/mL, and 7.23 μg/mL in MDA-MB-231, respectively. Cell cycle analysis also indicated that D. bulbifera prompted apoptosis at various stages, and a significant decrease in viable cells was detected within 24 h and substantially improved after 48 h and 72 h of treatment. Phytochemical profiling of methanol extract revealed the presence of 39 metabolites such as acetic acid, n-hexadecanoic acid, acetin, hexadecanoate, 7-tetradecenal, phytol, octadecanoic acid, cholesterol, palmitic acid, and linolenate. Hence, these findings concluded that D. bulbifera extract has promising anticancer and natural antioxidant agents. However, further study is needed to isolate the bioactive compounds and validate the effectiveness of this extract in the In in vivo model.
Matched MeSH terms: Gas Chromatography-Mass Spectrometry
Impaired wound healing is one of the serious problems among the diabetic patients. Currently, available treatments are limited due to side effects and cost effectiveness. In line with that, we attempted to use a natural source to study its potential towards the wound healing process. Therefore, Alternanthera sessilis (A. sessilis), an edible and medicinal plant, was chosen as the target sample for the study. During this investigation, the wound closure properties using stem extract of A. sessilis were analyzed. Accordingly, we analyzed the extract on free radical scavenging capacity and the cell migration of two most prominent cell types on the skin, human dermal fibroblast (NHDF), keratinocytes (HaCaT), and diabetic human dermal fibroblast (HDF-D) to mimic the wound healing in diabetic patients. The bioactive compounds were identified using gas chromatography-mass spectrometry (GC-MS). We discovered that the analysis exhibited a remarkable antioxidant, proliferative, and migratory rate in NHDF, HaCaT, and HDF-D in dose-dependent manner, which supports wound healing process, due to the presence of wound healing associated phytocompounds such as Hexadecanoic acid. This study suggested that the stem extract of A. sessilis might be a potential therapeutic agent for skin wound healing, supporting its traditional medicinal uses.
Matched MeSH terms: Gas Chromatography-Mass Spectrometry
Cat's whiskers (Orthosiphon stamineus) leaves extracts were prepared using supercritical CO2 (SC-CO2) with full factorial design to determine the optimum extraction parameters. Nine extracts were obtained by varying pressure, temperature, and time. The extracts were analysed using FTIR, UV-Vis, and GC-MS. Cytotoxicity of the extracts was evaluated on human (colorectal, breast, and prostate) cancer and normal fibroblast cells. Moderate pressure (31.1 MPa) and temperature (60°C) were recorded as optimum extraction conditions with high yield (1.74%) of the extract (B2) at 60 min extraction time. The optimized extract (B2) displayed selective cytotoxicity against prostate cancer (PC3) cells (IC50 28 µg/mL) and significant antioxidant activity (IC50 42.8 µg/mL). Elevated levels of caspases 3/7 and 9 in B2-treated PC3 cells suggest the induction of apoptosis through nuclear and mitochondrial pathways. Hoechst and rhodamine assays confirmed the nuclear condensation and disruption of mitochondrial membrane potential in the cells. B2 also demonstrated inhibitory effects on motility and colonies of PC3 cells at its subcytotoxic concentrations. It is noteworthy that B2 displayed negligible toxicity against the normal cells. Chemometric analysis revealed high content of essential oils, hydrocarbon, fatty acids, esters, and aromatic sesquiterpenes in B2. This study highlights the therapeutic potentials of SC-CO2 extract of cat's whiskers in targeting prostate carcinoma.
Matched MeSH terms: Gas Chromatography-Mass Spectrometry
Nasopharyngeal carcinoma (NPC) is a malignancy that occurs in the epithelium of the nasopharynx. The standard treatment of NPC patients with locoregionally advanced stages is problematic and is often associated with toxicities. Therefore, it is essential to screen for naturally occurring compounds with strong apoptosis-inducing activity and minimal toxicity. This study investigated the effects of the standardized methanol extract of Cinnamomum burmannii Blume stem bark and its main constituent, trans-cinnamaldehyde (TCA), on human NPC cell lines. The content of TCA in C. burmannii methanol extract was standardized to be 13.61% w/w by means of gas chromatography-mass spectrometry (GC-MS). NPC cell proliferation was clearly inhibited within 24 h of treatment, with TCA exhibiting greater activity than the methanol extract. TCA was more active against NPC cells compared with cisplatin. There was a pronounced downregulation of the proliferation markers, Ki67 and proliferating cell nuclear antigen (PCNA) in the TCA-treated cells; while morphological observation indicated the induction of apoptosis. Caspase activation and prominent DNA damage, which are markers of apoptosis induction were detected. TCA demonstrated the ability to scavenge nitric oxide. The simultaneous combination of TCA and cisplatin produced synergistic anti-proliferative effects. Collectively, these data indicate the potential use of TCA for the treatment of NPC.
Matched MeSH terms: Gas Chromatography-Mass Spectrometry
Entamoeba histolytica is a causative agent of amoebic liver abscess (ALA) and is endemic in many underdeveloped countries. We investigated antigenic E. histolytica proteins in liver abscess aspirates using proteomics approach. Pus samples were first tested by real-time PCR to confirm the presence of E. histolytica DNA and the corresponding serum samples tested for E. histolytica-specific IgG by a commercial ELISA. Proteins were extracted from three and one pool(s) of pus samples from ALA and PLA (pyogenic liver abscess) patients respectively, followed by analysis using isoelectric focussing, SDS-PAGE and Western blot. Unpurified pooled serum samples from infected hamsters and pooled human amoebic-specific IgG were used as primary antibodies. The antigenic protein band was excised from the gel, digested and analysed by MALDI-TOF/TOF and LC-MS/MS. The results using both primary antibodies showed an antigenic protein band of ∼14kDa. Based on the mass spectrum analysis, putative tyrosine kinase is the most probable identification of the antigenic band.
Matched MeSH terms: Gas Chromatography-Mass Spectrometry
Isoprenoids are a large, diverse group of secondary metabolites which has recently raised a renewed research interest due to genetic engineering advances, allowing specific isoprenoids to be produced and characterized in heterologous hosts. Many researches on metabolic engineering of heterologous hosts for increased isoprenoid production are focussed on Escherichia coli and yeasts. E. coli, as most prokaryotes, use the 2-C-methyl-d-erythritol-4-phosphate (MEP) pathway for isoprenoid production. Yeasts on the other hand, use the mevalonate pathway which is commonly found in eukaryotes. However, Lactococcus lactis is an attractive alternative host for heterologous isoprenoid production. Apart from being food-grade, this Gram-positive prokaryote uses the mevalonate pathway for isoprenoid production instead of the MEP pathway. Previous studies have shown that L. lactis is able to produce sesquiterpenes through heterologous expression of plant sesquiterpene synthases. In this work, we analysed the gene expression of the lactococcal mevalonate pathway through RT-qPCR to successfully engineer L. lactis as an efficient host for isoprenoid production. We then overexpressed the mvk gene singly or co-expressed with the mvaA gene as an attempt to increase β-sesquiphellandrene production in L. lactis. It was observed that co-expression of mvk with mvaA doubled the amount of β-sesquiphellandrene produced.
Matched MeSH terms: Gas Chromatography-Mass Spectrometry
Characterization of anthracene metabolites produced by Armillaria sp. F022 was performed in the enzymatic system. The fungal culture was conducted in 100-mL Erlenmeyer flask containing mineral salt broth medium (20 mL) and incubated at 120 rpm for 5-30 days. The culture broth was then centrifuged at 10,000 rpm for 45 min to obtain the extract. Additionally, the effect of glucose consumption, laccase activity, and biomass production in degradation of anthracene were also investigated. Approximately, 92 % of the initial concentration of anthracene was degraded within 30 days of incubation. Dynamic pattern of the biomass production was affected the laccase activity during the experiment. The biomass of the fungus increased with the increasing of laccase activity. The isolation and characterization of four metabolites indicated that the structure of anthracene was transformed by Armillaria sp. F022 in two routes. First, anthracene was oxidized to form anthraquinone, benzoic acid, and second, converted into other products, 2-hydroxy-3-naphthoic acid and coumarin. Gas chromatography-mass spectrometry analysis also revealed that the molecular structure of anthracene was transformed by the action of the enzyme, generating a series of intermediate compounds such as anthraquinone by ring-cleavage reactions. The ligninolytic enzymes expecially free extracellular laccase played an important role in the transformation of anthracene during degradation period.
Matched MeSH terms: Gas Chromatography-Mass Spectrometry
This paper examines the processing steps of extracting palm oil from fresh fruit bunches in a way that may impact on the formation of chloropropandiol fatty esters (3-MCPD esters), particularly during refining. Diacylglycerols (DAGs) do not appear to be a critical factor when crude palm oils are extracted from various qualities of fruit bunches. Highly hydrolysed oils, in spite of the high free fatty acid (FFA) contents, did not show exceptionally high DAGs, and the oils did not display a higher formation of 3-MCPD esters upon heat treatment. However, acidity measured in terms of pH appears to have a strong impact on 3-MCPD ester formation in the crude oil when heated at high temperatures. The differences in the extraction process of crude palm oil from current commercial processes and that from a modified experimental process showed clearly the effect of acidity of the oil on the formation of 3-MCPD esters. This paper concludes that the washing or dilution step in palm oil mills removes the acidity of the vegetative materials and that a well-optimised dilution/washing step in the extraction process will play an important role in reducing formation of 3-MCPD esters in crude palm oil upon further heat processing.
Matched MeSH terms: Gas Chromatography-Mass Spectrometry
The study aimed to establish the detection method for bound 3-, 2-MCPD, and glycidol using accelerated solvent extraction (ASE) and gas chromatography mass spectrometry (GC-MS). The ASE was modified for reduced solvent volume and process time to extract lipid from the chocolate spread, infant formula, potato chips, and sweetened creamer. The solvent selected for ASE was a mixture of iso-hexane and acetone at 100°C with the lipid and analyte recovery ranging from 96.9% to 98.6% and 84.1% to 107.5%, respectively. The derivatisation of analytes was adopted from the AOCS method Cd29a-13 for GC-MS analysis. The results showed that the coefficient of determination (R2) of all analytes was >0.99. The limit of detection (LOD) was 0.1 mg kg-1 expressed in lipid basis for both bound 3- and 2-MCPD and 0.2 mg kg-1 expressed in lipid basis for bound glycidol. The limit of quantitation (LOQ) was 0.3 mg kg-1 expressed in lipid basis for both bound 3- and 2-MCPD and 0.6 mg kg-1 expressed in lipid basis for bound glycidol. A blank spiked with 3-monochloropropanediols fatty acid esters (MCPDE) and 2-MCPDE (0.3, 2.1, and 7.2 mg kg-1) and glycidol esters (0.6, 4.7, and 16.6 mg kg-1) were chosen for accuracy and precision tests. The recoveries were 91.7% to 105.9%. Both repeatability and within-laboratory reproducibility of the analysis were within the acceptable level of precision ranging from 1.7% to 16%. This is the first time that a full validation procedure extending to both accuracy and precision tests has been carried out for sweetened creamer and chocolate spread. Overall, the combined protocol of ASE and AOCS Cd29a-13 was successfully validated for both solid and liquid food samples with lipid content from 10% to 30%.
Matched MeSH terms: Gas Chromatography-Mass Spectrometry
An average 50 ml breast milk samples were collected from 21 lactating primiparous mothers (range 25 to 45 years, mean 33 years), 4-8 weeks after delivery in Penang Island, Malaysia. The geometric mean concentration of the most toxic congeners, 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) was 0.14 pg WHO2005-TEQ g-1 zlipid. The most abundant congeners of PCDD/Fs were octachlorodibenzo-p-dioxin (OCDD) (5.9-75.4%), followed by 1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin (1,2,3,4,6,7,8-HpCDD) (1.1-30.7%). The geometric mean level of total dioxins and dl-PCBs was 2.2 pg WHO2005-TEQ g-1 lipid, significantly lower than those in developed countries or highly contaminated areas. The total dioxins and dl-PCBs in pg WHO2005-TEQ levels in breast milk were significantly correlated with years of residence at potential contaminated site. The average daily intake of 11.8 pg WHO2005-TEQ kg-1 body weight was estimated for a breastfed infant at 6 months of age. This demonstrates the exposure risk to infants, especially from Penang region, to these pollutants from human milk intake are potentially high during the lactation period.
Matched MeSH terms: Gas Chromatography-Mass Spectrometry