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Objective To analyze the influence of different processing methods,including frying,ginger frying,and salt frying,on the volatile components of A.fructus.Methods The volatile components in different processed products of A.fructus were detected and analyzed by gas chromatography-mass spectrometry(GC-MS)based on multivariate statistical analysis.After OPLS-DA analysis,the different components were screened under the conditions of VIP>1.5 and P<0.05 and were qualitatively searched using the NIST 11 spectral library.Results A total of 49 different components were identified,with 14 components only changing in the seed mass and 22 components changing in the peel.The content of camphor could be significantly reduced in the seed mass after A.fructus was processed and the content of bornyl acetate significantly increased in the peel of frying A.fructus.Salt frying had a great influence on the alkanes in A.fructus,and ginger processing did not only increase the volatile components in ginger,which reflected the complexity of the processing mechanism.Conclusion At present,the specific processing mechanism is not clear,but the experimental results provide theoretical data for the "detoxification and efficiency enhancement" effect of A.fructus processing,reflecting the scientific nature of the processing,enriching the processing theory of A.fructus,and providing a reference for further in-depth research on the activity of different processed products of A.fructus.
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ObjectiveTo screen the differential markers by analyzing volatile components in Dalbergia odorifera and its counterfeits, in order to provide reference for authentication of D. odorifera. MethodThe volatile components in D. odorifera and its counterfeits were detected by headspace gas chromatography-mass spectrometry(HS-GC-MS), and the GC conditions were heated by procedure(the initial temperature of the column was 50 ℃, the retention time was 1 min, and then the temperature was raised to 300 ℃ at 10 ℃ for 10 min), the carrier gas was helium, and the flow rate was 1.0 mL·min-1, the split ratio was 10∶1, and the injection volume was 1 mL. The MS conditions used electron bombardment ionization(EI) with the scanning range of m/z 35-550. The compound species were identified by database matching, the relative content of each component was calculated by the peak area normalization method, and principal component analysis(PCA), orthogonal partial least squares-discrimination analysis(OPLS-DA) and cluster analysis were performed on the detection results by SIMCA 14.1 software, and the differential components of D. odorifera and its counterfeits were screened out according to the variable importance in the projection(VIP) value>2 and P<0.05. ResultA total of 26, 17, 8, 22, 24 and 7 volatile components were identified from D. odorifera, D. bariensis, D. latifolia, D. benthamii, D. pinnata and D. cochinchinensis, respectively. Among them, there were 11 unique volatile components of D. odorifera, 6 unique volatile components of D. bariensis, 3 unique volatile components of D. latifolia, 6 unique volatile components of D. benthamii, 8 unique volatile components of D. pinnata, 4 unique volatile components of D. cochinchinensis. The PCA results showed that, except for D. latifolia and D. cochinchinensis, which could not be clearly distinguished, D. odorifera and other counterfeits could be distributed in a certain area, respectively. The OPLS-DA results showed that D. odorifera and its five counterfeits were clustered into one group each, indicating significant differences in volatile components between D. odorifera and its counterfeits. Finally, a total of 31 differential markers of volatile components between D. odoriferae and its counterfeits were screened. ConclusionHS-GC-MS combined with SIMCA 14.1 software can systematically elucidate the volatile differential components between D. odorifera and its counterfeits, which is suitable for rapid identification of them.
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ObjectiveTo investigate the mechanism of Atractylodis Macrocephalae Rhizoma(AMR) in the treatment of slow-transmission constipation(STC) by observing the effects of AMR on short-chain fatty acids and intestinal barries in STC mice. MethodForty-eight male KM mice were randomly divided into blank group, model group, AMR low-, medium-, high-dose groups(2.5, 5, 10 g·kg-1) and mosapride group(2.5 mg·kg-1). Except for the blank group, all groups were gavaged with loperamide suspension(5 mg·kg-1) twice daily for 14 d to construct the STC mouse model. At the same time, each drug administration group was given the corresponding drug by gavage for consecutive 14 d, the blank and model groups were gavaged with equal volume of distilled water. The effects of the treatment of AMR on body mass, defecation frequency, fecal water content and intestinal propulsion rate of mice were observed, the pathological changes of mouse colon were observed by hematoxylin-eosin(HE) staining and periodic acid-Schiff(PAS) staining, the levels of gastrin(GAS) and motilin(MTL) in serum were detected by enzyme-linked immunosorbent assay(ELISA), gas chromatography-mass spectrometry(GC-MS) was used to detect the contents of short-chain fatty acids(SCFAs) in mouse feces, real-time fluorescence quantitative polymerase chain reaction(Real-time PCR) and Western blot were used to determine the mRNA and protein expression levels of zonula occludens-1(ZO-1), Occludin, and Claudin-1 in the colon of mice. ResultCompared with the blank group, the body mass, defecation frequency, fecal water content and intestinal propulsion rate of mice in the model group were significantly decreased(P<0.05, P<0.01), the arrangement of colonic tissues was disordered, and the number of goblet cells was reduced, the levels of GAS and MTL in serum were significantly decreased(P<0.01), and the levels of SCFAs in the feces were on a decreasing trend, with the contents of acetic acid, propionic acid, butyric acid, isobutyric acid and valeric acid were significantly decreased(P<0.05, P<0.01), the mRNA and protein expression levels of ZO-1, Occludin and Claudin-1 in the colonic tissues were significantly decreased(P<0.01). The above results suggested that STC mouse model was successfully constructed. Compared with the model group, the body mass, defecation frequency, fecal water content and intestinal propulsion rate of mice in AMP administration groups all increased significantly(P<0.05, P<0.01), the mucosal layer of the colonic tissues was structurally intact without obvious damage, and the number of goblet cells increased, serum levels of GAS and MTL were significantly increased(P<0.01), the contents of SCFAs in the feces were all on a rising trend, with the contents of acetic, propionic, butyric and isobutyric acids rising significantly(P<0.05, P<0.01), the mRNA and protein expression levels of ZO-1, Occludin and Claudin-1 in the colonic tissues were significantly increased(P<0.05, P<0.01). ConclusionAMR is able to improve the constipation symptoms in STC mice, and its mechanism may be related to increasing the contents of SCFAs in the intestine as well as promoting the mRNA and protein expression levels of ZO-1, Occludin and Claudin-1 in the colon.
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AIM To establish a GC-MS method for the simultaneous content determination of sixteen pesticide residues in Lycii Fructus and perform safety assessment.METHODS The analysis was performed on DB-5MS chromatographic column(30 m×0.25 mm,0.25 μm)subjected to the programmed heating,with splitless injection of 1.0 μL dissolved sample at a flowing rate of 1.0 mL/min.Other parameters were as follows:injection port temperature of 250℃,electron impact ionization(EI),electron energy of 70 eV;ion source temperature of 230℃,multi-reaction monitoring mode,and collision gas.of high-purity N2.Pesticide residues with relatively high dietary risk were analyzed and discussed with regard to residue levels,dietary intake risk,risk ranking and cumulative exposure assessment.RESULTS Sixteen pesticides showed good linear relationships within their own ranges(r≥0.994 4),whose average recoveries were 70%-114%,with the RSDs of less than 2%.The highest average cyfluthrin residue of 0.999 2 mg/kg in Lycii Fructus of production regions and the highest average cypermethrin residue of 0.088 4 mg/kg in Lycii Fructus commodities were both detected.In Lycii Fructus of production regions with chronic hazard index(HI)value of 0.012 9 and acute HI value of 0.065 5 and their commodities with chronic HI of 0.001 2 and acute HI of 0.005 4,the pesticide residue of cypermethrin was the leading cause of chronic and acute dietary risk,and additionally,pyridaben within maximum residue limit(MRL)was the only detectectable highly toxic pesticide among the other most concerning pestcides of deltamethrin,pyridaben,chlorpyrifos,dichlorvos and methidathion.CONCLUSION There exist pesticide residues within MRL values in some samples of Lycii Fructus and the use of cypermethrin should be well-controlled.
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Abstract This study presents the first preliminary phytochemical screening and investigation of the lipoidal matter of Latania verschaffeltii Lem. leaves, belonging to the Arecaceae family. Gas chromatography coupled with mass spectroscopy (GC/MS) was used to analyze and identify compounds of saponifiable and unsaponifiable content. The preliminary phytochemical screening of total methanolic extract of Latania verschaffeltii Lem. leaves revealed the presence of unsaturated sterols and/or triterpenes, carbohydrates and/or glycosides, flavonoids, tannins, saponins, and phenolic acids in the leaves. However, cardenolides, cyanogenic compounds, alkaloids, and iridoids were not detected. The results of the gas chromatography/mass spectrometry (GC/MS) analysis indicated that the percentage of saturated fatty acids (83.82%) is higher than that of unsaturated fatty acids (9.42%). The predominant methyl ester of a saturated fatty acid detected in the sample was hexadecanoic acid methyl ester, accounting for 41.68% of the total. The composition of the unsaponifiable matter consisted of hydrocarbons (5.66%), fatty alcohols (0.96%), terpenes (85.97%), and sterols (2.18%). The major terpenes observed were phytol (43.62%) and squalene (39.27%).
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Triage , Plant Leaves/adverse effects , Arecaceae/classification , Egypt/ethnology , Phytochemicals/analysis , Alkaloids/agonists , Gas Chromatography-Mass Spectrometry/methodsРеферат
The aim of this study was to identify the chemical composition of the Piper arboreum Aubl. essential oil (EO), and to evaluate its inhibitory activity in vitro against the enzymes butyrylcholinesterase (BuChE) and acetylcholinesterase (AChE). The EO was obtained by steam distillation of the leaves, which were collected in Pindal canton of the Loja province in southern Ecuador. The chemical composition was analyzed using the gas chromatography technique coupled to a mass spectrometry detector (GC-MS) and gas chromatography coupled to a flame ionization detector (GC-FID). A total of 41 compounds were identified, the major components found in the oil were limonene (31,46%), ß-selinene (12,01%), (E)-caryophyllene (7,53%), bicyclogermacrene (6,72%), germacrene D (3,83%) and ß-elemene (3,63%). In in vitro analyzes, the EO showed high selective inhibition for BuChE with an IC50 inhibition value of 29,3±3,3 µg/mL. By contrast, the EO was not active against the AChE enzyme (IC50was 100,1±15,2 µg/mL).
El objetivo del presente estudio consistió en identificar la composición química del aceite esencial de la especie Piper arboreum Aubl. y evaluar su actividad inhibitoria in vitro frente a las enzimas butirilcolinesterasa (BuChE) y acetilcolinesterasa (AChE). El aceite esencial (AE) se obtuvo mediante destilación por arrastre de vapor de las hojas de la planta, que se colectaron en el cantón Pindal de la provincia de Loja al sur de Ecuador. La composición química se analizó mediante la técnica de cromatografía de gases acoplado a un detector de espectrometría de masas (GC-MS) y cromatografía de gases acoplado a un detector de ionización de llama (GC-FID). Se identificaron en total 41 compuestos, siendo los mayoritarios, el limoneno (31,46%), ß-selineno (12,01%), (E)-cariofileno (7,53%), biciclogermacreno (6,72%), germacreno D (3,83%) y ß-elemeno (3,63%). En los análisis in vitro, el AE mostró una alta inhibición selectiva para BuChE con un valor de inhibición CI50 de 29,3±3,3 µg/mL. Por el contrario,el AE no resultó activo frente a la enzima AChE con un valor de inhibión CI50= 100,1±15,2 µg/mL.
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Acetylcholinesterase/chemistry , Butyrylcholinesterase/chemistry , Piper/chemistry , Oils, Volatile/pharmacology , Oils, Volatile/chemistry , Ecuador , Gas Chromatography-Mass Spectrometry/methodsРеферат
Anti-hyperglycemic agents is a substance that helps a person with diabetes control their level of glucose (sugar) in the blood. It includes insulin and oral anti-hyperglycemic agents. Diabetes is a metabolic disorder characterized by increased blood glucose levels leading to other major complications. Thus, obtaining these anti hyperglycemic agents through easily available flora is necessary. Delonix regia , a tree cultivated worldwide, has also been used as traditional medicine in various disorders. Aim of the project work was to evaluate the anti-hyperglycemic activity in the hydroalcoholic extract of D. regia bark for the treatment of hyperglycemia. The collected bark was dried, powdered and extracted through cold maceration method. The extract was further concentrated to obtain a gummy mass of the hydroalcoholic extract. The extract was subjected to phytochemical analysis through conventional chemical tests and GC-MS. After the identification of the phytoconstituents, they were studied for their clinically proven properties. In-vitro anti-hyperglycemic studies were carried out through assays like alpha-amylase inhibition assay and alpha-glucosidase inhibition assay. The results of the extract were compared with results of standard acarbose. The IC 50 standard values in alpha-amylase inhibition assay and ?-glucosidase inhibition assay were 98.77 and 84.33 ?g/mL, respectively. The IC 50 values of hydroalcoholic extract of D. regia bark in alpha-amylase and alpha-glucosidase inhibition assay were 167 and 116.31 ?g/mL, respectively. From the study, the hydroalcoholic extract of bark of D. regia exhibit anti-hyperglycemic activity compared to standard acarbose.
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Background & objectives: The main aim of this research is to provide literature on the Ocimum plant, and to know the significance of the Ocimum species carried out by pharmacognostic study and experimental design for GC-MS. Ocimum genus are very important for their therapeutic potential among the most important aromatic herbs. Methods: Extreme attention has been put on literature reports in which the utilization of tulsi and their pharmacognostic study has been done by performing morphological and microscopic leaf experimental design and by using essential oil through the GC-MS instrumentation method. Results:The utilization of these characteristics would be important for the drug discovery scientist to develop a specific formulation of the crude drug, which will be a magical therapeutic agent in the future, with many advantages. GC-MS chromatogram of Ocimum sanctum, Ocimum canum, and Ocimum gratissimum oil showed major peaks and has been identified after comparison of the mass spectra with the NIST library, indicating the presence of three phytocomponents. From the results, the GC-MS study suggested that anethole which is well reported antimicrobial compound is more in O. canum (2.66%) in comparison to O. sanctum (1,28%) but absent in O. gratissimum. The results indicated that the antimicrobial activity is more in O. canum due to the presence ofa high amount of anethole in comparison to O. gratissimum and O. sanctum. Interpretation & conclusion: The result revealed that O. canum has a microscopic character that can be identified by the characteristic GC MS analysis of extracts to distinguish between different species of the ocimum plant.
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OBJECTIVES@#To establish the GC-MS qualitative and quantitative analysis methods for the synthetic cannabinoids, its main matrix and additives in suspicious electronic cigarette (e-cigarette) oil samples.@*METHODS@#The e-cigarette oil samples were analyzed by GC-MS after diluted with methanol. Synthetic cannabinoids, its main matrix and additives in e-cigarette oil samples were qualitatively analyzed by the characteristic fragment ions and retention time. The synthetic cannabinoids were quantitatively analyzed by using the selective ion monitoring mode.@*RESULTS@#The linear range of each compound in GC-MS quantitative method was 0.025-1 mg/mL, the matrix recovery rate was 94%-103%, the intra-day precision relative standard deviations (RSD) was less than 2.5%, and inter-day precision RSD was less than 4.0%. Five indoles or indazole amide synthetic cannabinoids were detected in 25 e-cigarette samples. The main matrixes of e-cigarette samples were propylene glycol and glycerol. Additives such as N,2,3-trimethyl-2-isopropyl butanamide (WS-23), glycerol triacetate and nicotine were detected in some samples. The content range of synthetic cannabinoids in 25 e-cigarette samples was 0.05%-2.74%.@*CONCLUSIONS@#The GC-MS method for synthesizing cannabinoid, matrix and additive in e-cigarette oil samples has good selectivity, high resolution, low detection limit, and can be used for simultaneous qualitative and quantitative analysis of multiple components; The explored fragment ion fragmentation mechanism of the electron bombardment ion source of indole or indoxamide compounds helps to identify such substances or other compounds with similar structures in cases.
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Gas Chromatography-Mass Spectrometry/methods , Electronic Nicotine Delivery Systems , Illicit Drugs/analysis , Indazoles/chemistry , Glycerol/analysis , Cannabinoids , Indoles/chemistry , IonsРеферат
Aims@#This study was aimed at evaluating the phytochemical components and antibacterial activity of crude extracts of Allium sativum and Gongronema latifolium on multidrug-resistant isolates from clinical samples.@*Methodology and results@#Collection of clinical samples [wounds (43) and throat (17)] and plant leaves, preparation of extracts, gas chromatography-mass spectrophotometer (GC-MS), isolation and characterization of bacterial isolates were all carried out using standard microbiological techniques. Antibiotic resistance studies were conducted using the Kirby-Bauer disc diffusion method. Antibacterial assay of plant extracts was evaluated using the agar well diffusion method. From the results obtained, Gram-negative bacteria isolated were found to be 73.7% while Gram-positive were 26.3%. The result also showed that Staphylococcus aureus had the highest occurrence rate of 12(21.1%), while Citrobacter sp. 2(3.5%) was the least occurring bacteria organism isolated from the clinical samples. The antibiotic susceptibility pattern evaluated showed at least one resistance in all the clinical bacterial isolates. The results showed that all the isolates were resistant to imipenem with the exception of Citrobacter sp. The results of GC-MS analysis of plant extracts identified fourteen and twelve bioactive compounds in the leaf extracts of G. latifolium and A. sativum, respectively. All extracts showed antibacterial activity with zones of inhibition ranging from 04 to 28 mm against the different resistant bacteria used. Ethanol extracts showed higher antibacterial activity as compared to aqueous extracts. @*Conclusion, significance and impact of study@#The overall results of the present work provide baseline information for the possible use of these plants in treating bacterial infections involving MDR phenotypes. Thus, this study could serve as a foundation for exploring the potential of bioactive compounds of G. latifolium and A. sativum for the discovery of new antimicrobial drugs.
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Objective To investigate the differences in chemical components and bacterial diversity on the surface of Citrus reticulata at various drying temperatures(35、45、55、65℃).Methods At various drying temperatures,Citrus reticulata from Dahongpao produced in Chongqing Wanzhou was dried.By using HPLC,the effects of various drying temperatures on the hesperidin,hesperidin,and kaempferin concentrations in Citrus reticulata were examined.By using GC-MS,the effects of various drying temperatures on the Citrus reticulata volatile components were examined.The differences in bacterial population structure on the surface of Citrus reticulata at various drying temperatures were examined using high throughput sequencing.Results The higher the temperature,the quicker Citrus reticulata will dry.The amount of hesperidin and hesperidin in Citrus reticulata was not significantly affected by different drying temperatures.The amount of Citrus reticulata increased as the drying temperature rose.GC-MS analysis identified 15 main components in Citrus reticulata,and the proportion of some volatile aroma components decreased with the increase of drying temperature;Such as laurylene,linalool,carvol α-Orange aldehyde,etc.With the increase of drying temperature,the dominant bacteria of Proteobacteria has an upward trend.At the same time,the dominant bacteria of Halomonas and Porphyromonas have changed to Metallobacterium.Conclusion If the drying temperature is too high,the volatile components in the dried Citrus reticulata may be transformed or destroyed due to the instability of heating.The difference of the bacterial flora on the surface of Citrus reticulata at different drying temperatures may cause the change of the volatile components in the later aging process.Considering the quality of dried tangerine peel,low temperature and hot air drying is the better drying method.
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Objective To study the changes of volatile oil of Atractylodis Rhizoma(AR)and Atractylodis macrocephalae Rhizoma(AMR)before and after co-decocting in different proportions(1∶3,1∶2,1∶1,2∶1,3∶1).Methods The volatile oil was extracted by steam distillation and analyzed by gas chromatography-mass spectrometry(GC-MS).Results After co-decocting,the yield of volatile in each group was higher than in single decocting.The relative contents of most components in the mixed volatile oil after co-decocting were significantly different from the theoretical calculation.Co-decocting could promote the extraction of hinesol,which is the main component of the essential oil of AR,and the compatibility with large doses of AMR(1∶2 and 1∶3)could also promote the dissolution of β-eudesmol.At the same time,the extraction of atractylon,germacrene B and valencene was inhibited by co-decocting,which were the main constituents of the volatile oil of AMR.Conclusion Co-decocting of AR and AMR could improve the extraction rate and change the chemical composition of volatile oil.After co-decocting,the dissolution of active components of AR increased,while the dissolution of active components of AMR decreased.It may lead to the change of pharmacological activity.
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Objective To investigate the chemical composition from the flowers of Callerya speciosa,and reveal the metabolites difference at different flowering periods based on metabolomics technology.Methods The primary and secondary metabolites,volatile chemical components in flowers of C.speciosa were analyzed combined by GC-MS and UPLC-Q-Exactive MS.Principal component analysis(PCA),orthogonal partial least squares-discriminant analysis(OPLS-DA),and hierarchical cluster analysis(HCA)were performed to identify differential metabolites.Results A total of 332 compounds were identified by UPLC-Q-Exactive MS,mainly including secondary metabolites such as flavonoids,triterpenoids,phenylpropanoids.A total of 297 compounds were identified by GC-MS,mainly including primary metabolites and volatile chemical components,such as organic acids,amino acids,saccharides,heterocycles,alcohols.The PCA analysis demonstrated that the metabolites of the four flowering periods were divided into two groups:bud,initial bloom and blooming periods clustered into one group,while wilting period clustered into the other group,the main differences were filtered and identified as flavonoids and triterpenoids,organic acids,respectively.Compared to the upright type,the flowers of vine type contained more characteristic flavonoids as differential metabolites during the bud,initial bloom and blooming periods,and some flavonoids decrease gradually with the development of flowering.Conclusion The results indicated that the flowers of C.speciosa possessed abundant active flavonoid metabolites for further utilization,and the best harvest stage is initial bloom,the best harvest plant is vine type.This study provides a scientific basis for the scientific development and rational use of the flowers of C.speciosa.
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Objective The identification of Santali Albi Lignum and its common counterfeits Osyris lanceolata Lignum,Santalum spicatum Lignum was studied to provide experimental basis for the authenticity of this medicinal herb.Methods The identification was carried out using morphological,microscopic,and thin-layer identification methods.The volatile oil of Santali Albi Lignum and its counterfeits were extracted by steam distillation and the volatile oil components were analyzed by gas chromatography-mass spectrometry(GC-MS).The differences of volatile oil components among the three were compared.Results Santali Albi Lignum and its common counterfeits all possessed a sandalwood aroma,but Santali Albi Lignum has abundant oiliness and strong aroma.Osyris lanceolata Lignum aroma exhibits slightly strong odor and slightly camphor flavor,and the smell of Santalum spicatum Lignum is sweet and fragrant.Santali Albi Lignum is greyish-yellow to yellowish-brown in color,while Osyris lanceolata Lignum is generally reddish brown in color,Santalum spicatum Lignum is light yellow to light yellowish-brown,but its surface shows reddish-brown when exposed to air for a long time.In the transection section,the ray width of Santali Albi Lignum is more than 1-2 rows of cells,with occasional 3 rows of cells.The ray width of Osyris lanceolata Lignum is 1-3 rows of cells,while the ray width of Santalum spicatum Lignum is 1-2 rows of cells,mostly uniseriate.In the tangential section,the wood ray of Santali Albi Lignum has a height of 5-15 cells,the wood ray of Osyris lanceolata Lignum has a height of 4-10 cells,while the wood ray of Santalum spicatum Lignum has a height of 4-16 cells.In the radial section,fewer calcium oxalate crystal was found in Santali Albi Lignum,more calcium oxalate crystal was appeared in Osyris lanceolata Lignum,more and larger calcium oxalate crystal was identified in Santalum spicatum Lignum.Genuine and fake sandalwood can be distinguished using sandalwood oil as the thin-layer chromatographic reference.And the volatile oil content of fake Osyris lanceolata Lignum and Santalum spicatum Lignum is lower than that of Santali Albi Lignum.The main components of Santali Albi Lignum are α-santalol and β-santalol.The low content of santalol has been found in Osyris lanceolata Lignum,while α-santalol is extremely low in Santalum spicatum Lignum oil and β-santalol has not been found.Conclusion There are small differences among Santali Albi Lignum and its adulterants in characteristics,microscopical characteristics.But the differences have been found in three-way cross section,thin layer chromatography,volatile oil content and composition characteristics,which can be used for identification of Santali Albi Lignum and its counterfeits.
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ObjectiveTo establish a GC-MS method for the detection of 9 halogenated alkanes in toothpastes. MethodsVarious brands of toothpastes on the market were collected as the samples. Methanol was used as the extraction solution. After shaking, vortex and centrifugation, the supernatant was filtered by 0.45 μm microporous filter membrane. The content of 9 halogenated alkanes including chloromethane, dichloromethane, chloroform, 1,1,1-trichloroethane, carbon tetrachloride, 1,2-dichloroethane, 1,1,2-trichloroethane, 1,2-dibromoethane, 1,2,3-trichloropropane in the filtrate were determined by GC-MS. ResultsThe 9 halogenated alkanes showed a good linear relationship in the concentration range of 0.03‒1.00 μg·mL-1. The correlation coefficient was ≥0.998 7 with the detection limits of 0.015‒0.056 mg·kg-1. The spiked recoveries were 83.2%‒108.9% with the RSD of 2.0%‒9.8%. In the actual sample analysis, 1,1,2-trichloroethane and 1,2,3-trichloropropane were respectively detected in 6 toothpaste samples from 5 brands. ConclusionThe method is simple, sensitive, accurate, and has good spiked recoveries. It can be used for the determination of halogenated alkanes in toothpastes.
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Objective To analyze the diagnosis cases of occupational benzene poisoning in gas station industry, and to explore the application of GC-MS technology in occupational disease diagnosis. Methods The epidemiological method was used to describe and analyze the occupational disease diagnosis of 15 gas station workers , and qualitative screening of occupational hazard factors was performed by GC-MS. Results All the 15 workers had more than one year's occupation history of oil refueling and unloading. The clinical manifestations were consistent with the characteristics of chronic benzene poisoning in diagnosis of occupational benzene poisoning. However, due to lack of evidence of occupational exposure to benzene and incomplete diagnostic data, occupational chronic benzene poisoning was not diagnosed. GC-MS technology was used to screen the occupational hazard factors in the gas station workplace, and benzene, n-pentane, n-hexane and so on were found. Conclusion GC-MS is recommended for qualitative screening of organic solvents such as benzene when diagnosing occupational diseases for gas station workers , so as to accurately identify occupational hazard factors in workplaces and provide reliable basis for diagnosis of occupational diseases.
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ObjectiveBy comparing the differences in composition and content of volatile components between Atractylodis Macrocephalae Rhizoma(AMR)and bleaching AMR, bran-fried AMR and bran-fried bleaching AMR, the effect of processing with rice-washed water on the volatile components in AMR and bran-fried AMR were investigated. MethodHeadspace gas chromatography-mass spectrometry(HS-GC-MS)was used to determine the volatile components in raw products, bran-fried products and their processed products with rice-washed water. GC conditions were programmed temperature(starting temperature of 50 ℃, rising to 140 ℃ at 10 ℃·min-1, maintained for 5 min, then rising to 210 ℃ at 4 ℃·min-1), splitting ratio of 10∶1, high purity helium as the carrier gas and a solvent delay time of 3 min. MS conditions were an electron bombardment ion source(EI) with an electron collision energy of 70 eV, ion source temperature of 230 ℃, and the detection range of m/z 20-650. The relative contents of the components were determined by the peak area normalization method, the obtained sample data were subjected to principal component analysis(PCA) and orthogonal partial least squares-discriminant analysis(OPLS-DA) by SIMCA 14.1 software, and the differential components of AMR and bleaching AMR, and bran-fried AMR and bran-fried bleaching AMR were screened according to variable importance in the projection(VIP) value>1 and P<0.05. ResultA total of 71 volatile components were identified, including 53 in AMR, 50 in bleaching AMR, 51 in bran-fried AMR, and 44 in bran-fried bleaching AMR. OPLS-DA results showed that there were significant differences between AMR and bleaching AMR, bran-fried AMR and bran-fried bleaching AMR, but not between AMR samples from different origins. The compound composition of AMR and bleaching AMR, bran-fried AMR and bran-fried bleaching AMR did not change, but the contents of monoterpenes and sesquiterpenes changed significantly. ConclusionSignificant changes in the contents of volatile components were observed in AMR and bleaching AMR, bran-fried AMR and bran-fried bleaching AMR, among them, 1,2-dimethyl-4-methylidenecyclopentene, 9,10-dehydro-isolongifolene, γ-elemene, zingiberene, atractylone, silphinene, modhephene and (1S,4S,4aS)-1-isopropyl-4,7-dimethyl-1,2,3,4,4a,5-hexahydronaphthalene can be used as candidate differential markers of volatile components of AMR before and after processing with rice-washed water.
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ObjectiveTo analyze the fingerprint of six pungent herbs based on the molecular connectivity index(MCI)and the matching frequency total statistical moment method, and to study the division and integration of the "imprinting template" of their volatile components, so as to find the common "imprinting template" characteristics of the pungent herbs. MethodThe volatile components of six pungent herbs were extracted by steam distillation, and their fingerprints were established by gas chromatography-mass spectrometry(GC-MS) with a programmed temperature increase(80 ℃ for 5 min, 5 ℃·min-1 to 200 ℃ for 5 min, 2 ℃·min-1 to 230 ℃ for 10 min), a splitting ratio of 20∶1, an electron bombardment ion source(EI) and the detection range of m/z 35-650, and the average MCI and total statistical moment parameters of the fingerprints were calculated. Then the matching frequency method was used to classify, integrate and confirm the chromatographic peaks of the fingerprints of six pungent herbs. ResultThe average zero order, first-order and second-order MCI values of the volatile components of Pogostemonis Herba, Artemisiae Argyi Folium, Atractylodis Rhizoma, Asari Radix et Rhizoma, Magnoliae Flos and Schizonepetae Herba were 9.02, 5.28 and 5.05, respectively. The average values of peak number, total zero-order moment, total first-order moment and total second-order moment were 60, 169×107, 22.49 min and 36.82 min2, respectively. The 20 integrated imprinting templates were obtained by the matching frequency method for the six pungent herbs, among which three were common imprinting templates with the retention times of (25.97±0.21),(26.90±0.20),(31.64±1.24) min, respectively, and the representative components were valencene,β-elemene, caryophyllin, etc. ConclusionMCI combined the matching frequency total statistical moment can divide and integrate the characteristics of imprinting templates of six pungent herbs, and find their common chromatographic imprinting characteristics, which can provide a reference for the determination of effective substances of pungent herbs.
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ObjectiveTo investigate the key compounds affecting the irritation and to clarify the effect of heating and the addition of ginger juice as the auxiliary material during the processing on the irritation of Magnoliae Officinalis Cortex(MOC) by comparing the irritation and composition of volatile oil in MOC and its different processed products. MethodVolatile oil in raw products, water-processed products, ginger-dried products, ginger-fried products(the amounts of ginger were 10%, 50%, respectively) of MOC were extracted by steam distillation and subjected to rabbit eye irritation experiment, and the volatile components of each sample were detected by gas chromatography-mass spectrometry(GC-MS). Principal component analysis(PCA)and orthogonal partial least squares-discriminant analysis(OPLS-DA) were used to analyze the data of each sample by SIMCA 14.1. The relative contents of different processed products were compared two by two with those of and raw products or ginger-fried products, and the markers that might be related to the irritation were sorted out according to the principles of variable importance in the projection(VIP) value >1 and P<0.05, and the factors influencing the differences in irritation were analyzed. ResultCompared with the blank group, the administration groups all had irritation to the eyes of rabbits, and the degree of irritation was in the order of raw products>water-processed products>ginger-dried products>ginger-fried products(10%)>ginger-fried products(50%). The results of PCA and OPLS-DA showed that there were differences in the volatile oil from raw products and different processed products. According to VIP value>1 and P<0.05, and combined with the results of eye irritation experiment, ten volatile compounds related to irritation changes were screened out. Among them, cis-cinnamaldehyde was only detected in raw products, the relative contents of β-caryophyllene, (+)-delta-cadinene, α-humulene, γ-muurolene, (-)-isoledene and citral all increased to different degrees, the contents of p-cymene, 1(10)-4-cadinadien-15-ol and β-eudesmol all decreased to different degrees. ConclusionThe irritation of MOC is reduced after heating and processing with ginger juice, and the synergistic effect of both is more effective for reducing irritation. Among the differential markers associated with changes in irritation, the increase in the relative content of citral is closely related to the addition of ginger juice, while the decrease in the relative contents of cis-cinnamaldehyde, p-cymene, 1(10)-4-cadinadien-15-ol is related to heating, and the changes of other components may be related to the synergistic effect of heating and ginger juice.
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ObjectiveBy exploring the volatile components, polysaccharide composition and changes in the contents of five carbohydrate components of Polygonatum cyrtonema rhizoma before and after processing, and then the effect of yellow rice wine on the odour formation of P. cyrtonema rhizoma was investigated. MethodThe volatile components of P. cyrtonema rhizoma before and after processing were detected by headspace gas chromatography-mass spectrometry(HS-GC-MS), and sample data were subjected to principal component analysis(PCA) and orthogonal partial least squares-discriminant analysis(OPLS-DA) using SIMCA 14.1, then the differences between these components of P. cyrtonema rhizoma before and after processing were screened according to the principle of variable importance in the projection(VIP) value>1. Crude carbohydrate components in raw and wine-processed P. cyrtonema rhizoma were subjected to oxime and silylation, the carbohydrate components were analyzed by gas chromatography-mass spectrometry(GC-MS/MS), and the relative contents of various components were calculated by peak area normalization, then quantitative analysis of four carbohydrate components was also carried out. ResultA total of 23 volatile components were identified from the raw products and the wine-processed products, including 15 components in raw products and 20 components in wine-processed products. Among them, 2-methylbutyraldehyde and isovaleraldehyde had a sweet odor and their contents increased after processing, but the contents of hexanal and caproic acid decreased, new components such as 2-acetylfuran and 5-methylfuranal were produced after processing. PCA and OPLS-DA results showed that there were significant differences between raw products and the wine-processed products, a total of 13 differential compounds were screened out, of which 7 showed an upward trend in relative content and 6 showed a downward trend. A total of 7 carbohydrate components, including 5 monosaccharides and 2 disaccharides, were identified in raw products and the wine-processed products. The results of determination showed that the contents of fructose, glucose, mannose and sucrose in P. cyrtonema rhizoma increased after wine-processing, and their increases were 4.54, 1.51, 2.93, 3.66 times, respectively. ConclusionAfter processing, the increase of aromatic flavor of P. cyrtonema rhizoma may be related to the increase of the contents of aldehydes such as 2-methylbutyraldehyde and isovaleraldehyde, while the decrease of raw flavor may be related to the decrease of the contents of volatile components such as hexanal and hexanoic acid, the increase of sweet flavor may be related to the increase of the contents of monosaccharides and oligosaccharides such as fructose and sucrose.