Background:Ethoxyquin(EQ)is a common antioxidant which is widely used in animal feed.But the supplement of EQ in animal feed may lead to the residues of EQ and its major oxidation products:ethoxyquin quinone imine(EQI...Background:Ethoxyquin(EQ)is a common antioxidant which is widely used in animal feed.But the supplement of EQ in animal feed may lead to the residues of EQ and its major oxidation products:ethoxyquin quinone imine(EQI)and ethoxyquin dimer(EQDM)in animal tissue.Thus,it would pose potential health hazards to consumers.However,the method for the simultaneous determination of EQ,EQI and EQDM in animal tissues is currently not available,and the accumulation extend of these chemicals in animal tissues after EQ administration remains to be evaluated.Results:A gas chromatography-tandem mass spectrometry method was successfully developed for the simultaneous determination of EQ,EQI and EQDM in swine tissues.The quantitative limits of EQ,EQI and EQDM can achieve to 0.5,5.0 and 5.0μg/kg in swine tissues,respectively.The spiked-recovery ratios of the three analytes(5–2000μg/kg)were in the range of 64.7%–100.7%with relative standard deviations below 11.6%.Moreover,the utilization of this method for the analysis of actual swine tissue samples revealed that the application of commercial EQ additive in swine diet would produce the residues of all the three chemicals(EQ,EQI and EQDM)in fat,kidney,liver and muscle.Conclusions:The assay accuracy and precision of this GC-MS/MS method can meet the requirement of quantitative analysis.Meanwhile,the safety of EQ as a feed additive should be seriously considered with regard to food safety concerns since the oxidation product of EQ may have potential carcinogenicity.展开更多
Quality control of ginseng currently is mainly based on ginsenoside analysis,but rarely focuses on the volatile organic components.In the current work,an untargeted metabolomics approach,by headspace solid-phase micro...Quality control of ginseng currently is mainly based on ginsenoside analysis,but rarely focuses on the volatile organic components.In the current work,an untargeted metabolomics approach,by headspace solid-phase micro-extraction gas chromatography/mass spectrometry(HS-SPME-GC/MS),was elaborated and further employed to holistically compare the compositional difference of the volatile components simultaneously from 12 Panax herbal medicines,which included P.ginseng(PG),P.quinquefolius(PQ),P.notoginseng(PN),red ginseng(PGR),P.ginseng leaf(PGL),P.quinquefolius leaf(PQL),P.notoginseng leaf(PNL),P.ginseng flower(PGF),P.quinquefolius flower(PQF),P.notoginseng flower(PNF),P.japonicus(PJ),and P.japonicus var.major(PJvm).Chromatographic separation was performed on an HP-5MS elastic quartz capillary column using helium as the carrier gas,enabling good resolution within 1 h.We were able to characterize totally 259 volatile compounds,including 82 terpenes(T),46 alcohols(Alc),29 ketones(K),25 aldehydes(Ald),21 esters(E),and the others.By analyzing 90 batches of ginseng samples based on the untargeted metabolomics workflows,236 differential ions were unveiled,and accordingly 36 differential volatile components were discovered.It is the first report that simultaneously compares the compositional difference of volatile components among 12 Panax herbal medicines,and useful information is provided for the quality control of ginseng aside from the well-known ginsenosides.展开更多
As a new technology of analyzing crude oils,comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry(GC×GCTOFMS) has received much research attention.Here we present a case s...As a new technology of analyzing crude oils,comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry(GC×GCTOFMS) has received much research attention.Here we present a case study in the Junggar Basin of NW China.Results show that the hydrocarbons,including saturates and aromatics,were all well-separated without large coelution,which cannot be realized by conventional one-dimensional GC-MS.The GC×GC technique is especially effective for analyzing aromatics and low-to-middlemolecular-weight hydrocarbons,such as diamondoids.The geochemical characteristics of crude oils in the study area were investigated through geochemical parameters extracted by GC×GC-TOFMS,improving upon the understanding obtained by GC-MS.Thus,the work here represents a new successful application of GC×GCTOFMS,showing its broad usefulness in petroleum geochemistry.展开更多
In present work,the volatile constituents of Curcuma longa L.,A.lancea (Thunb.) DC.,Foeniculum vulgare Mill,and Cinnamomun cassia Presl.have been analyzed by flash distillation/capillary gas chro-matography/mass spect...In present work,the volatile constituents of Curcuma longa L.,A.lancea (Thunb.) DC.,Foeniculum vulgare Mill,and Cinnamomun cassia Presl.have been analyzed by flash distillation/capillary gas chro-matography/mass spectrometry.The results are consistent with those obtained by conventional steam distillation extraction method.The optimum condition of flash distillation has been studied.The experimental results showed that this new technique proved to be a simple,rapid and efficient tool for microanalysis of volatile constituents of Chinese medicinal herbs.展开更多
The Asian rice gall midge(Orseolia oryzae WoodMason) is a serious pest of rice that causes huge loss in yield.While feeding inside the susceptible host,maggots secrete substances that facilitate the formation of a h...The Asian rice gall midge(Orseolia oryzae WoodMason) is a serious pest of rice that causes huge loss in yield.While feeding inside the susceptible host,maggots secrete substances that facilitate the formation of a hollow tube-like structure called gall and prevent panicle formation.The present investigation was carried out to get an account of biochemical changes occurring in the rice plant upon gall midge feeding.Metabolic profiling of host tissues from three rice varieties,namely,TN1,Kavya,and RP2068,exposed to gall midge biotype 1(GMB1),was carried out using gas chromatography mass spectrometry(GC-MS).TN1 and GMB1 represented compatible interaction,while Kavya and GMB1 as well as RP2068 and GMB1 represented incompatible interactions.The current study identified several metabolites that could be grouped as resistance,susceptibility,infestation,and host features based on their relative abundance.These may be regarded as biomarkers for insect-plant interaction in general and rice-gall midge interaction in particular.展开更多
Objectives:The ageing process has a significant impact on the aroma of Chinese Baijiu,which could strengthen the desirable flavor characteristics and reduce the undesirable ones.The aim of this study was to observe th...Objectives:The ageing process has a significant impact on the aroma of Chinese Baijiu,which could strengthen the desirable flavor characteristics and reduce the undesirable ones.The aim of this study was to observe the in itiation of mean in gful cha nges in volatile fracti on and locate the ageing markers during ageing storage of Chinese Highland Qingke Baijiu.Materials and Methods:Samples of Chinese Qingke Baijiu were aged for 0,1,2,3,4,5,6,7,8,9,10,and 11 mon ths before an alysis.The samples were isolated by liquid-liquid extraction and then analyzed by comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry.The acquired data were processed by untargeted and targeted metabolomics approach to locate the ageing markers.Results:The untargeted metabolomics analysis(hierarchical clustering analysis,HCA)shows that the chemical composition of Qingke Baijiu presents a statistically sigrdficant deviation from the reference scenario after 5 mon ths.Subsequently,supervised statistics analysis(orthogo nal partial least squares discrimination analysis)was performed to locate the markers,which changed sigrdficantly during ageing.Fifteen markers were located,and seven of them were acetals.Notably,1,1-diethoxy-propane,1,1-diethoxy-butane,and 1,1-diethoxy-3-methyl-butane are important contributors to the flavor of Chinese Baijiu.The identified markers were applied for the untargeted metabolomics(HCA),and the results revealed that these markers could divide the Qingke Baijiu into two ageing stages,0-5 months and 6-11 months.Conclusion:The results suggest that it is a valuable tool for monitoring the changes of volatile compounds and locating the age markers in Chinese Baijiu.展开更多
To investigate the chemical transformation of volatile compounds in sulfur-fumigated Radix Angelicae Sinensis. A comprehensive two-dimensional gas chromatography (GCxGC) and high-resolution time-of-flight mass spectro...To investigate the chemical transformation of volatile compounds in sulfur-fumigated Radix Angelicae Sinensis. A comprehensive two-dimensional gas chromatography (GCxGC) and high-resolution time-of-flight mass spectrometry (HR-TOF/MS) with colorized fuzzy difference (CFD) method was used to investigate the effect of sulfur-fumigation on the volatile components from Radix Angelicae Sinensis. Twenty-five compounds that were found in sun-dried samples disappeared in sulfur-fumigated samples. Seventeen volatile components including two sulfur-containing compounds were newly generated for the first time in volatile oils of sulfur-fumigated Radix Angelicae Sinensis. The strategy can be successfully applied to rapidly and holistically discriminate sun-dried and sulfur-fumigated Radix Angelicae Sinensis. GCxGC-HR-TOF/MS based CFD is a powerful and feasible approach for the global quality evaluation of Radix Angelicae Sinensis as well as other herbal medicines.展开更多
In this work, solid-phase microextraction coupled with gas chromatography–mass spectrometry was developed to determine trace levels of nitrobenzene compounds in water and soil samples. Graphene was chosen as the extr...In this work, solid-phase microextraction coupled with gas chromatography–mass spectrometry was developed to determine trace levels of nitrobenzene compounds in water and soil samples. Graphene was chosen as the extraction material and its composite was coated on a stainless steel wire through sol–gel technique for the solid phase microextraction. The key parameters influencing the extraction efficiency were optimized. Under the optimal conditions, the linearity for the compounds was observed in the range of 0.02–15.0 mg/L for water samples, and 0.2–60.0 mg/kg for soil samples, with the correlation coefficients(r) of 0.9966–0.9987. The limits of detection of the method were 0.0025–0.005 mg/L for water samples, and 0.02–0.04 mg/kg for soil samples. The recoveries for the spiked samples were in the range of 72.0%–113.2%, and the precision, expressed as the relative standard deviations, was less than 12.1%.展开更多
A rapid, inexpensive and laboratory friendly method was developed for analysis of off-flavor/odor compounds in fresh and salt water using gas chromatography with chemical ionization-tandem mass spectrometry. Off-flavo...A rapid, inexpensive and laboratory friendly method was developed for analysis of off-flavor/odor compounds in fresh and salt water using gas chromatography with chemical ionization-tandem mass spectrometry. Off-flavor/odor compounds, included geosmin, 2- methylisobomeol (MIB), 2-isobutyl-3-methyoxypyrazine (IBMP), and 2-isopropyl-3-methoxypyrazine (IPMP). Using this method, a single sample can be extracted within minutes using only 1 mL of organic solvent. The ion transitions for IPMP, IBMP, MIB, and geosmin were 153 〉 121, 167 〉 125, 152 〉 95, and 165 〉 109, respectively. The linearity of this method for analyzing MIB ranged from 4 to 200ng·L^-1, and from 0.8 to 200ng·L^-1 for the other analytes. Method recoveries ranged from 97% to 111% and percent relative standard deviations ranged from 3% to 9%, indicating that the method is accurate, precise, and reliable.展开更多
A rapid,sensitive,and cost-effective analyticalmethod was developed for the analysis of selected semivolatileorganic compounds in water.The method used anautomated online solid-phase extraction technique coupledwith p...A rapid,sensitive,and cost-effective analyticalmethod was developed for the analysis of selected semivolatileorganic compounds in water.The method used anautomated online solid-phase extraction technique coupledwith programmed-temperature vaporization large-volumeinjection gas chromatography/mass spectrometry.Thewater samples were extracted by using a fully automatedmobile rack system based on x-y-z robotic techniquesusing syringes and disposable 96-well extraction plates.The method was validated for the analysis of 30 semivolatileanalytes in drinking water,groundwater,andsurface water.For a sample volume of 10 mL,the linearcalibrations ranged from 0.01 or 0.05 to 2.5μg·L^(-1),and themethod detection limits were less than 0.1μg·L^(-1).For thereagent water samples fortified at 1.0μg·L^(-1)and2.0μg·L^(-1),the obtained mean absolute recoveries were70%-130%with relative standard deviations of less than20%for most analytes.For the drinking water,groundwater,and surface water samples fortified at 1.0μg·L^(-1),theobtained mean absolute recoveries were 50%-130%withrelative standard deviations of less than 20%for mostanalytes.The new method demonstrated three advantages:1)no manipulation except the fortification of surrogatestandards prior to extraction;2)significant cost reductionassociated with sample collection,shipping,storage,andpreparation;and 3)reduced exposure to hazardous solventsand other chemicals.As a result,this new automatedmethod can be used as an effective approach for screeningand/or compliance monitoring of selected semi-volatileorganic compounds in water.展开更多
Objectives:A rapid and sensitive gas chromatography–mass spectrometry(GC–MS)method for quantitative and qualitative analysis of essential oil from Curcuma wenyujin rhizomes was established.Methods:The essential oil ...Objectives:A rapid and sensitive gas chromatography–mass spectrometry(GC–MS)method for quantitative and qualitative analysis of essential oil from Curcuma wenyujin rhizomes was established.Methods:The essential oil of C.wenyujin rhizomes was extracted by supercritical CO2 extraction(SFE).Six main bioactive compounds(eucalyptol,β-elemene,curzerene,germacrone,curdione,and curcumol)were analyzed in selected ion monitoring mode(SIM).Results:Curzerene is not originally present in C.wenyujin rhizomes,but is a product of the transformation of furanodiene at high temperature.The six target components demonstrated good linearity(R2>0.9979)over a relatively wide concentration range.The interday and intraday variations had relative standard deviation values less than 5%and the average recovery ranged from 96.95%to 100.04%.The limit of quantitation ranged from 0.032 to 0.235μg/mL.The developed method was successfully used to analyze the six compounds in 17 samples collected from different origins.Significant variation was observed for the concentrations of the six compounds.In addition,51 constituents were identified in C.wenyujin rhizome essential oil,consisting of 87.66%of the total essential oil,including curdione,curzerene,dehydrocurdione,germacrone,1,4-bis(2-benzimidazoyl)benzene,neocurdione,curcumenone,andβ-elemene.Conclusions:The proposed method will be useful in the quality control of C.wenyujin rhizome essential oil production.展开更多
Research on pollution characteristics and toxicities of emerging polycyclic aromatic sulfur heterocycles(PASHs) in PM_(2.5) has not been reported due to the lack of analytical method with the needed performance.In the...Research on pollution characteristics and toxicities of emerging polycyclic aromatic sulfur heterocycles(PASHs) in PM_(2.5) has not been reported due to the lack of analytical method with the needed performance.In the present study,a novel method for the determination of 14 PASHs in PM_(2.5) was developed using atmospheric pressure gas chro matography-tandem mass spectrometry(APGC-MS/MS).Atmospheric pressure chemical ionization was operated with multiple reaction monitoring in positive ionization mode.High sensitivity(method detection limit <1.673 pg/m^(3)),acceptable re coveries(67.6%-120.8%) and precisions(RSD of 2.2%-15.4%) were obtained.The method was successfully applied for analyzing PASHs in 10 PM_(2.5) samples collected from Taiyuan,a typical industrial city in China,in 2016,The total concentrations were from 929 pg/m^(3) to 14,593 pg/m^(3).The determined levels indicated that further investigations on environmental fate and toxicities of PM_(2.5)-bound PASHs may be needed.展开更多
The aim of this study was to develop a gas chromatography‑mass spectrometry(GC‑MS)‑based metabolomics method to distinguish different kinds of poisons in the blood.We examined the changes in blood metabolites using GC...The aim of this study was to develop a gas chromatography‑mass spectrometry(GC‑MS)‑based metabolomics method to distinguish different kinds of poisons in the blood.We examined the changes in blood metabolites using GC‑MS following administration of four different poisons(paraquat,dichlorvos,aconitine,and sodium nitrite).The data were analyzed with orthogonal partial least squares.Then,total and single differential metabolite profiles were evaluated with support vector machine(SVM)models.The results showed that various metabolites(5‑ketone proline,1,5‑anhydrohexitol,lactic acid,glycine 2,2‑furoic acid,and 3‑hydroxybutyric acid)were differential between the experimental groups and the control groups.The accuracy rates of the SVM models established using total and single differential metabolites were 80%and 100%,respectively.In conclusion,we successfully developed a poison screening method.The established SVM models can distinguish four kinds of poisons and could be used to establish a complete poison metabonomic information database.Furthermore,some of the metabolites could be biomarkers of these poisons.Finally,both the models and potential biomarkers may reduce the time required for poison detection and provide direction for solving cases and auxiliary diagnosis.展开更多
Many new psychoactive substances(NPSs)with different chemical structures have emerged in the illicit drug market in the last decade.The present work was aimed at the development of a simple method in gas chromatograph...Many new psychoactive substances(NPSs)with different chemical structures have emerged in the illicit drug market in the last decade.The present work was aimed at the development of a simple method in gas chromatography/mass spectrometry(MS)for the determination of NPS of different classes,the use of cannabinoids,and,at the same time,the evaluation of methadone therapy in hair matrix,within our routine analysis control for methadone treatment or from autopsy cases.The determination of synthetic cannabinoids and methadone therapy used an extraction method based on incubation in concentrated sodium hydroxide(NaOH)solution,providing a dissolution of the keratin matrix.The described method was applied on 15 authentic specimens from our cases:five showed the presence of methadone and 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine(EDDP).The described method can be useful not only in the forensic investigation of NPS-related addiction histories but also in epidemiological and retrospective studies on the spread of NPS among specific safety-sensitive social workers.The GC instrument was an Agilent 7820A(Agilent Technologies,Santa Clara,CA,USA),and the detection system was an Agilent 5977B single quadrupole MS operating in selective ion monitoring mode.Wlidation parameters such as limit of detections(LODs),limit of quantifications(LOQs),repeatability,accuracy,and linearity were satisfactory for its application on real specimens.LODs,LOQs,2?2,%CY standard deviation,and the mean concentration for the analyzed compounds are reported in Table lb.Accuracy and repeatability were acceptable for all the analytes at their respective LOQs.Recovery experiments varied from 58.3%to 103.0%,thus allowing the application on authentic specimens.The described method can be useful not only in the forensic investigation ofNPS-related addiction histories but also in epidemiological and retrospective studies on the spread of NPS among specific safety-sensitive social workers,such as drivers.展开更多
The status of PCDDs and PCDFs content in retail foods from a certain area by Isotope Dilution HRGC-HRMS was surveyed and the local population PCDD/Fs exposure from diverse foods and health risk was evaluated.PCDD/Fs w...The status of PCDDs and PCDFs content in retail foods from a certain area by Isotope Dilution HRGC-HRMS was surveyed and the local population PCDD/Fs exposure from diverse foods and health risk was evaluated.PCDD/Fs was extracted from samples by Soxhlet extraction,concentrated and purified by FMS column chromatograph,carbon column enrichment.Confirmation and quantitative analysis at pg/g level of PCDD/Fs was performed by HRGC/HRMS using multiple ion detection mode(MID).TEQ concentration was calculated by WHO-TEF multiplying by concentration of seventeen PCDD/Fs congener.Median of PCDD/Fs concentration for fish,livestock,poultry,egg,vegetable oil,milk,vegetable totally 100 samples for ten diverse foods didn’t exceed the limit standards by EU.The level of PCDD/Fs for different food in the certain area was lower or comparable to the data reported by developed country in the world.The total weekly intake and monthly intake for local population or national population was 3.44,14.8 WHO-TEQ/kg BW and 1.5,6.42 pg WHO-TEQ/kg BW respectively,the value was lower than the Tolerable Weekly Intake of 14 pg WHO TEQ/kg BW for PCDDs,PCDFs and dioxin-like PCBs established by EU Scientific Committee for Food.The dietary PCDD/Fs intake for local people was higher than national population.And animal food was the dominant contributor to the total dietary intake,which accounted for more than 70 percent.These levels of consumption of diverse food containing typical levels of PCDD/Fs doesn’t present a risk to the health of the local population.But integrative dietary intake could be evaluated including of PCBs intake for population in the future.展开更多
基金supported the Ministry of Agriculture of the People’s Republic of China.
文摘Background:Ethoxyquin(EQ)is a common antioxidant which is widely used in animal feed.But the supplement of EQ in animal feed may lead to the residues of EQ and its major oxidation products:ethoxyquin quinone imine(EQI)and ethoxyquin dimer(EQDM)in animal tissue.Thus,it would pose potential health hazards to consumers.However,the method for the simultaneous determination of EQ,EQI and EQDM in animal tissues is currently not available,and the accumulation extend of these chemicals in animal tissues after EQ administration remains to be evaluated.Results:A gas chromatography-tandem mass spectrometry method was successfully developed for the simultaneous determination of EQ,EQI and EQDM in swine tissues.The quantitative limits of EQ,EQI and EQDM can achieve to 0.5,5.0 and 5.0μg/kg in swine tissues,respectively.The spiked-recovery ratios of the three analytes(5–2000μg/kg)were in the range of 64.7%–100.7%with relative standard deviations below 11.6%.Moreover,the utilization of this method for the analysis of actual swine tissue samples revealed that the application of commercial EQ additive in swine diet would produce the residues of all the three chemicals(EQ,EQI and EQDM)in fat,kidney,liver and muscle.Conclusions:The assay accuracy and precision of this GC-MS/MS method can meet the requirement of quantitative analysis.Meanwhile,the safety of EQ as a feed additive should be seriously considered with regard to food safety concerns since the oxidation product of EQ may have potential carcinogenicity.
基金National Natural Science Foundation of China(Grant No.81872996)Natural Science Foundation of Tianjin of China(Grant No.20JCYBJC00060).
文摘Quality control of ginseng currently is mainly based on ginsenoside analysis,but rarely focuses on the volatile organic components.In the current work,an untargeted metabolomics approach,by headspace solid-phase micro-extraction gas chromatography/mass spectrometry(HS-SPME-GC/MS),was elaborated and further employed to holistically compare the compositional difference of the volatile components simultaneously from 12 Panax herbal medicines,which included P.ginseng(PG),P.quinquefolius(PQ),P.notoginseng(PN),red ginseng(PGR),P.ginseng leaf(PGL),P.quinquefolius leaf(PQL),P.notoginseng leaf(PNL),P.ginseng flower(PGF),P.quinquefolius flower(PQF),P.notoginseng flower(PNF),P.japonicus(PJ),and P.japonicus var.major(PJvm).Chromatographic separation was performed on an HP-5MS elastic quartz capillary column using helium as the carrier gas,enabling good resolution within 1 h.We were able to characterize totally 259 volatile compounds,including 82 terpenes(T),46 alcohols(Alc),29 ketones(K),25 aldehydes(Ald),21 esters(E),and the others.By analyzing 90 batches of ginseng samples based on the untargeted metabolomics workflows,236 differential ions were unveiled,and accordingly 36 differential volatile components were discovered.It is the first report that simultaneously compares the compositional difference of volatile components among 12 Panax herbal medicines,and useful information is provided for the quality control of ginseng aside from the well-known ginsenosides.
基金funded by the Major State Basic Research Development Program of China(973 project,Grant No.2012CB214803)National Science and Technology Major Project of China(Grant No. 2016ZX05003-005)National Natural Science Foundation of China(Grant Nos.41322017 and 41472100)
文摘As a new technology of analyzing crude oils,comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry(GC×GCTOFMS) has received much research attention.Here we present a case study in the Junggar Basin of NW China.Results show that the hydrocarbons,including saturates and aromatics,were all well-separated without large coelution,which cannot be realized by conventional one-dimensional GC-MS.The GC×GC technique is especially effective for analyzing aromatics and low-to-middlemolecular-weight hydrocarbons,such as diamondoids.The geochemical characteristics of crude oils in the study area were investigated through geochemical parameters extracted by GC×GC-TOFMS,improving upon the understanding obtained by GC-MS.Thus,the work here represents a new successful application of GC×GCTOFMS,showing its broad usefulness in petroleum geochemistry.
文摘In present work,the volatile constituents of Curcuma longa L.,A.lancea (Thunb.) DC.,Foeniculum vulgare Mill,and Cinnamomun cassia Presl.have been analyzed by flash distillation/capillary gas chro-matography/mass spectrometry.The results are consistent with those obtained by conventional steam distillation extraction method.The optimum condition of flash distillation has been studied.The experimental results showed that this new technique proved to be a simple,rapid and efficient tool for microanalysis of volatile constituents of Chinese medicinal herbs.
基金Research on rice gall midge and gall midge-rice interaction in SN's laboratory is partially supported by coregrants from ICGEBextramural funding from the Department of Biotechnology(DBT)+1 种基金Indian Council of Agricultural Research(ICAR),Government of Indiathe University Grants Commission(UGC),Government of India,for a Junior Research Fellowship
文摘The Asian rice gall midge(Orseolia oryzae WoodMason) is a serious pest of rice that causes huge loss in yield.While feeding inside the susceptible host,maggots secrete substances that facilitate the formation of a hollow tube-like structure called gall and prevent panicle formation.The present investigation was carried out to get an account of biochemical changes occurring in the rice plant upon gall midge feeding.Metabolic profiling of host tissues from three rice varieties,namely,TN1,Kavya,and RP2068,exposed to gall midge biotype 1(GMB1),was carried out using gas chromatography mass spectrometry(GC-MS).TN1 and GMB1 represented compatible interaction,while Kavya and GMB1 as well as RP2068 and GMB1 represented incompatible interactions.The current study identified several metabolites that could be grouped as resistance,susceptibility,infestation,and host features based on their relative abundance.These may be regarded as biomarkers for insect-plant interaction in general and rice-gall midge interaction in particular.
基金supported by the National Key Research and Development Program of China(2016YFD0400500)the National Natural Science Foundation of China(No.32001826).
文摘Objectives:The ageing process has a significant impact on the aroma of Chinese Baijiu,which could strengthen the desirable flavor characteristics and reduce the undesirable ones.The aim of this study was to observe the in itiation of mean in gful cha nges in volatile fracti on and locate the ageing markers during ageing storage of Chinese Highland Qingke Baijiu.Materials and Methods:Samples of Chinese Qingke Baijiu were aged for 0,1,2,3,4,5,6,7,8,9,10,and 11 mon ths before an alysis.The samples were isolated by liquid-liquid extraction and then analyzed by comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry.The acquired data were processed by untargeted and targeted metabolomics approach to locate the ageing markers.Results:The untargeted metabolomics analysis(hierarchical clustering analysis,HCA)shows that the chemical composition of Qingke Baijiu presents a statistically sigrdficant deviation from the reference scenario after 5 mon ths.Subsequently,supervised statistics analysis(orthogo nal partial least squares discrimination analysis)was performed to locate the markers,which changed sigrdficantly during ageing.Fifteen markers were located,and seven of them were acetals.Notably,1,1-diethoxy-propane,1,1-diethoxy-butane,and 1,1-diethoxy-3-methyl-butane are important contributors to the flavor of Chinese Baijiu.The identified markers were applied for the untargeted metabolomics(HCA),and the results revealed that these markers could divide the Qingke Baijiu into two ageing stages,0-5 months and 6-11 months.Conclusion:The results suggest that it is a valuable tool for monitoring the changes of volatile compounds and locating the age markers in Chinese Baijiu.
基金Supported by the National Natural Science Foundation of China(No.81173546 and No.30940093)the Natural Science Foundation of Jiangsu Province,China(No.BK2009495)+4 种基金the International Science and Technology Cooperation Project of Jiangsu Province,China(No.BZ2011053)the Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD,No.2011ZYX2-001)the Postgraduate Research Innovation Project of Jiangsu Higher Education Institutions(No.KYLX_0975)the Chinese Medicine Research Program of Zhejiang Province,China(No.2014ZQ008)the Science Foundation of Zhejiang Chinese Medical University(No.2013ZZ12)
文摘To investigate the chemical transformation of volatile compounds in sulfur-fumigated Radix Angelicae Sinensis. A comprehensive two-dimensional gas chromatography (GCxGC) and high-resolution time-of-flight mass spectrometry (HR-TOF/MS) with colorized fuzzy difference (CFD) method was used to investigate the effect of sulfur-fumigation on the volatile components from Radix Angelicae Sinensis. Twenty-five compounds that were found in sun-dried samples disappeared in sulfur-fumigated samples. Seventeen volatile components including two sulfur-containing compounds were newly generated for the first time in volatile oils of sulfur-fumigated Radix Angelicae Sinensis. The strategy can be successfully applied to rapidly and holistically discriminate sun-dried and sulfur-fumigated Radix Angelicae Sinensis. GCxGC-HR-TOF/MS based CFD is a powerful and feasible approach for the global quality evaluation of Radix Angelicae Sinensis as well as other herbal medicines.
基金Financial support from the National Natural Science Foundation of China(No.31171698)the Innovation Research Group Program of Department of Education of Hebei for Hebei Provincial Universities(No.LJRC009)the Natural Science Foundation of Hebei Province(No.B2012204028)
文摘In this work, solid-phase microextraction coupled with gas chromatography–mass spectrometry was developed to determine trace levels of nitrobenzene compounds in water and soil samples. Graphene was chosen as the extraction material and its composite was coated on a stainless steel wire through sol–gel technique for the solid phase microextraction. The key parameters influencing the extraction efficiency were optimized. Under the optimal conditions, the linearity for the compounds was observed in the range of 0.02–15.0 mg/L for water samples, and 0.2–60.0 mg/kg for soil samples, with the correlation coefficients(r) of 0.9966–0.9987. The limits of detection of the method were 0.0025–0.005 mg/L for water samples, and 0.02–0.04 mg/kg for soil samples. The recoveries for the spiked samples were in the range of 72.0%–113.2%, and the precision, expressed as the relative standard deviations, was less than 12.1%.
文摘A rapid, inexpensive and laboratory friendly method was developed for analysis of off-flavor/odor compounds in fresh and salt water using gas chromatography with chemical ionization-tandem mass spectrometry. Off-flavor/odor compounds, included geosmin, 2- methylisobomeol (MIB), 2-isobutyl-3-methyoxypyrazine (IBMP), and 2-isopropyl-3-methoxypyrazine (IPMP). Using this method, a single sample can be extracted within minutes using only 1 mL of organic solvent. The ion transitions for IPMP, IBMP, MIB, and geosmin were 153 〉 121, 167 〉 125, 152 〉 95, and 165 〉 109, respectively. The linearity of this method for analyzing MIB ranged from 4 to 200ng·L^-1, and from 0.8 to 200ng·L^-1 for the other analytes. Method recoveries ranged from 97% to 111% and percent relative standard deviations ranged from 3% to 9%, indicating that the method is accurate, precise, and reliable.
基金The authors thank LEAP Technologies(Carrboro,NC,USA)for providing the technical support of the automated solid-phase extraction system.
文摘A rapid,sensitive,and cost-effective analyticalmethod was developed for the analysis of selected semivolatileorganic compounds in water.The method used anautomated online solid-phase extraction technique coupledwith programmed-temperature vaporization large-volumeinjection gas chromatography/mass spectrometry.Thewater samples were extracted by using a fully automatedmobile rack system based on x-y-z robotic techniquesusing syringes and disposable 96-well extraction plates.The method was validated for the analysis of 30 semivolatileanalytes in drinking water,groundwater,andsurface water.For a sample volume of 10 mL,the linearcalibrations ranged from 0.01 or 0.05 to 2.5μg·L^(-1),and themethod detection limits were less than 0.1μg·L^(-1).For thereagent water samples fortified at 1.0μg·L^(-1)and2.0μg·L^(-1),the obtained mean absolute recoveries were70%-130%with relative standard deviations of less than20%for most analytes.For the drinking water,groundwater,and surface water samples fortified at 1.0μg·L^(-1),theobtained mean absolute recoveries were 50%-130%withrelative standard deviations of less than 20%for mostanalytes.The new method demonstrated three advantages:1)no manipulation except the fortification of surrogatestandards prior to extraction;2)significant cost reductionassociated with sample collection,shipping,storage,andpreparation;and 3)reduced exposure to hazardous solventsand other chemicals.As a result,this new automatedmethod can be used as an effective approach for screeningand/or compliance monitoring of selected semi-volatileorganic compounds in water.
基金supported by National Natural Science Foundation of China(82074130)the Key Research Project of Hainan Province,China(ZDYF2020183)+1 种基金CAMS Innovation Fund for Medical Sciences(CIFMS)(2017-I2M-1-013)Natural Science Foundation of Hainan Province,China(Grant No.2019RC342)。
文摘Objectives:A rapid and sensitive gas chromatography–mass spectrometry(GC–MS)method for quantitative and qualitative analysis of essential oil from Curcuma wenyujin rhizomes was established.Methods:The essential oil of C.wenyujin rhizomes was extracted by supercritical CO2 extraction(SFE).Six main bioactive compounds(eucalyptol,β-elemene,curzerene,germacrone,curdione,and curcumol)were analyzed in selected ion monitoring mode(SIM).Results:Curzerene is not originally present in C.wenyujin rhizomes,but is a product of the transformation of furanodiene at high temperature.The six target components demonstrated good linearity(R2>0.9979)over a relatively wide concentration range.The interday and intraday variations had relative standard deviation values less than 5%and the average recovery ranged from 96.95%to 100.04%.The limit of quantitation ranged from 0.032 to 0.235μg/mL.The developed method was successfully used to analyze the six compounds in 17 samples collected from different origins.Significant variation was observed for the concentrations of the six compounds.In addition,51 constituents were identified in C.wenyujin rhizome essential oil,consisting of 87.66%of the total essential oil,including curdione,curzerene,dehydrocurdione,germacrone,1,4-bis(2-benzimidazoyl)benzene,neocurdione,curcumenone,andβ-elemene.Conclusions:The proposed method will be useful in the quality control of C.wenyujin rhizome essential oil production.
基金financial support from the National Natural Science Foundation of China (Nos.91843301 and 91543202)National Key Research and Development Program Cooperation on Scientific and Technological Innovation in Hong Kong,Macao and Taiwan (No. 2017YFE0191000)。
文摘Research on pollution characteristics and toxicities of emerging polycyclic aromatic sulfur heterocycles(PASHs) in PM_(2.5) has not been reported due to the lack of analytical method with the needed performance.In the present study,a novel method for the determination of 14 PASHs in PM_(2.5) was developed using atmospheric pressure gas chro matography-tandem mass spectrometry(APGC-MS/MS).Atmospheric pressure chemical ionization was operated with multiple reaction monitoring in positive ionization mode.High sensitivity(method detection limit <1.673 pg/m^(3)),acceptable re coveries(67.6%-120.8%) and precisions(RSD of 2.2%-15.4%) were obtained.The method was successfully applied for analyzing PASHs in 10 PM_(2.5) samples collected from Taiyuan,a typical industrial city in China,in 2016,The total concentrations were from 929 pg/m^(3) to 14,593 pg/m^(3).The determined levels indicated that further investigations on environmental fate and toxicities of PM_(2.5)-bound PASHs may be needed.
基金This work was financially supported by the project of the National Natural Sciences Foundation of China(No.81373239).
文摘The aim of this study was to develop a gas chromatography‑mass spectrometry(GC‑MS)‑based metabolomics method to distinguish different kinds of poisons in the blood.We examined the changes in blood metabolites using GC‑MS following administration of four different poisons(paraquat,dichlorvos,aconitine,and sodium nitrite).The data were analyzed with orthogonal partial least squares.Then,total and single differential metabolite profiles were evaluated with support vector machine(SVM)models.The results showed that various metabolites(5‑ketone proline,1,5‑anhydrohexitol,lactic acid,glycine 2,2‑furoic acid,and 3‑hydroxybutyric acid)were differential between the experimental groups and the control groups.The accuracy rates of the SVM models established using total and single differential metabolites were 80%and 100%,respectively.In conclusion,we successfully developed a poison screening method.The established SVM models can distinguish four kinds of poisons and could be used to establish a complete poison metabonomic information database.Furthermore,some of the metabolites could be biomarkers of these poisons.Finally,both the models and potential biomarkers may reduce the time required for poison detection and provide direction for solving cases and auxiliary diagnosis.
文摘Many new psychoactive substances(NPSs)with different chemical structures have emerged in the illicit drug market in the last decade.The present work was aimed at the development of a simple method in gas chromatography/mass spectrometry(MS)for the determination of NPS of different classes,the use of cannabinoids,and,at the same time,the evaluation of methadone therapy in hair matrix,within our routine analysis control for methadone treatment or from autopsy cases.The determination of synthetic cannabinoids and methadone therapy used an extraction method based on incubation in concentrated sodium hydroxide(NaOH)solution,providing a dissolution of the keratin matrix.The described method was applied on 15 authentic specimens from our cases:five showed the presence of methadone and 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine(EDDP).The described method can be useful not only in the forensic investigation of NPS-related addiction histories but also in epidemiological and retrospective studies on the spread of NPS among specific safety-sensitive social workers.The GC instrument was an Agilent 7820A(Agilent Technologies,Santa Clara,CA,USA),and the detection system was an Agilent 5977B single quadrupole MS operating in selective ion monitoring mode.Wlidation parameters such as limit of detections(LODs),limit of quantifications(LOQs),repeatability,accuracy,and linearity were satisfactory for its application on real specimens.LODs,LOQs,2?2,%CY standard deviation,and the mean concentration for the analyzed compounds are reported in Table lb.Accuracy and repeatability were acceptable for all the analytes at their respective LOQs.Recovery experiments varied from 58.3%to 103.0%,thus allowing the application on authentic specimens.The described method can be useful not only in the forensic investigation ofNPS-related addiction histories but also in epidemiological and retrospective studies on the spread of NPS among specific safety-sensitive social workers,such as drivers.
文摘The status of PCDDs and PCDFs content in retail foods from a certain area by Isotope Dilution HRGC-HRMS was surveyed and the local population PCDD/Fs exposure from diverse foods and health risk was evaluated.PCDD/Fs was extracted from samples by Soxhlet extraction,concentrated and purified by FMS column chromatograph,carbon column enrichment.Confirmation and quantitative analysis at pg/g level of PCDD/Fs was performed by HRGC/HRMS using multiple ion detection mode(MID).TEQ concentration was calculated by WHO-TEF multiplying by concentration of seventeen PCDD/Fs congener.Median of PCDD/Fs concentration for fish,livestock,poultry,egg,vegetable oil,milk,vegetable totally 100 samples for ten diverse foods didn’t exceed the limit standards by EU.The level of PCDD/Fs for different food in the certain area was lower or comparable to the data reported by developed country in the world.The total weekly intake and monthly intake for local population or national population was 3.44,14.8 WHO-TEQ/kg BW and 1.5,6.42 pg WHO-TEQ/kg BW respectively,the value was lower than the Tolerable Weekly Intake of 14 pg WHO TEQ/kg BW for PCDDs,PCDFs and dioxin-like PCBs established by EU Scientific Committee for Food.The dietary PCDD/Fs intake for local people was higher than national population.And animal food was the dominant contributor to the total dietary intake,which accounted for more than 70 percent.These levels of consumption of diverse food containing typical levels of PCDD/Fs doesn’t present a risk to the health of the local population.But integrative dietary intake could be evaluated including of PCBs intake for population in the future.