As a new technology of analyzing crude oils, comprehensive two-dimensional gas chromatography cou- pled with time-of-flight mass spectrometry （GCxGC- TOFMS） has received much research attention. Here we present a ca...As a new technology of analyzing crude oils, comprehensive two-dimensional gas chromatography cou- pled with time-of-flight mass spectrometry （GCxGC- TOFMS） 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 co- elution, which cannot be realized by conventional one-dimensional GC-MS. The GC×GC technique is especially effective for analyzing aromatics and low-to-middle- molecular-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×GC- TOFMS, showing its broad usefulness in petroleum geochemistry.展开更多
In recent decades, biotechnology produced a growth of knowledge on the causes and mechanisms of metabolic diseases that have formed the basis for their study, diagnosis and treatment. Unfortunately, it is well known t...In recent decades, biotechnology produced a growth of knowledge on the causes and mechanisms of metabolic diseases that have formed the basis for their study, diagnosis and treatment. Unfortunately, it is well known that the clinical features of metabolic diseases can manifest themselves with very different characteristics and escape early detection. Also, it is well known that the prognosis of many metabolic diseases is excellent if diagnosed and treated early. In this editorial we briefly summarized two groups of inherited metabolic diseases, the defects of cholesterol biosynthesis and those of bile acids. Both groups show variable clinical manifestations but some clinical signs and symptoms are common in both the defects of cholesterol and bile acids. The differential diagnosis can be made analyzing sterol profiles in blood and/or bile acids in blood and urine by chromatographic techniques(GC-MS and LC-MS/MS). Several defects of both biosynthetic pathways are treatable so early diagnosis is crucial. Unfortunately their diagnosis is made too late, due either to the clinical heterogeneity of the syndromes(severe, mild and very mild) that to the scarcity of scientific dissemination of these rare diseases. Therefore, the delay in diagnosis leads the patient to the medical observation when the disease has produced irreversible damages to the body. Here, we highlighted simple clinical and laboratory descriptions that can potentially make you to suspect a defect in cholesterol biosynthesis and/or bile acids, as well, we suggest appropriate request of the laboratory tests that along with common clinical features can help to diagnose these defects.展开更多
In this report, gas chromatography-mass spectrometry (GC-MS) based non-targeted metabolomics is used to develop appropriate headspace solid phase microextractions (HS-SPME) to enhance the understanding of volatile com...In this report, gas chromatography-mass spectrometry (GC-MS) based non-targeted metabolomics is used to develop appropriate headspace solid phase microextractions (HS-SPME) to enhance the understanding of volatile complexity of flue-cured tobacco leaves. Non-targeted metabolic profiling of GC-MS shows that the extraction condition of HS-SPME at 100?C for 30 min provides a better metabolite profile than other extraction conditions tested. GC-MS and principal component analyses (PCA) show that among five types of fibers tested, 100 μm polydimethylsiloxane (PMDS), 65 μm polydimethylsiloxane/divinylbenzene (PMDS/DVB) and 75 μm carboxen/polydimethylsiloxane (CAR/ PMS) provide a better reproducible metabolite profile. Based on an appropriate PDMS extraction condition optimized, we use GC-MS analysis and PCA to compare metabolite profiles in flue-cured leaves of tobacco plants grown in North Carolina, India and Brazil, respectively. The resulting data of PCA show that the global metabolic profiles in North Carolina samples are separated from those in Brazil and India samples, two groups of which are characterized by a partially overlapped pattern. Several peaks that were differentially accumulated in samples were annotated to known metabolites by deconvolution analysis, such as norsolanadione, solavetivone and rishtin. Norsolanadione is detected only in Brazil samples. Solavetivone is detected in samples of India and Brazil but not in those of North Carolina. Rishtin is detected in samples of North Carolina and India but not in Brazil samples. These data indicate that not only can a non-targeted metabolic profiling approach enhance the understanding of volatile complexity, but also can identify marker volatile metabolites in tobacco leaves produced in different growth regions.展开更多
Due to the harmful effect of free radical on physiological and pathological state of our body on one hand, and the increase of the fungal infection on the other hand, drug that can reduce free radical and inhibit fung...Due to the harmful effect of free radical on physiological and pathological state of our body on one hand, and the increase of the fungal infection on the other hand, drug that can reduce free radical and inhibit fungal growth is needed. This work aims to evaluate the antioxidant and antifungal activities of the Ocimum gratissimum L. essential oils from center and west region of Cameroon. Essential oil was analyzed by GC （gas chromatography） and GC coupled with MS （mass spectrometry）. The antioxidant activities of essential oils were studied by the Diphenylpicrylhydrazyl method and the β-carotene bleaching test. The antifungal activities were assessed using micro-dilution technique for yeasts and agar dilution method for Aspergillus. Thymol and γ-terpinene, eugenol and thymol were the major compounds for Yaounde and Dschang, respectively. The scavenging capacity of sample from Dschang was higher than that of Yaounde. Also, the β-carotene bleaching tests of the sample from Dschang were better than that from Yaounde. The antifungal activity of the sample from Yaounde was higher than that from Dschang on yeasts and Aspergillus isolates, respectively. This work presents and compares the chemical composition, antioxidant and antifungal activity of Ocimum gratissimum essential oil from center and west region of Cameroon.展开更多
To establish a new GC-MS/MS method for quantitative detection of 22 kinds of pesticide in fruit and vegetable including organic phosphorus,carbamate & pyrethrin etc.Working was performed by Xcalibur software with ...To establish a new GC-MS/MS method for quantitative detection of 22 kinds of pesticide in fruit and vegetable including organic phosphorus,carbamate & pyrethrin etc.Working was performed by Xcalibur software with multitask mode.We Carried on qualitative and quantitative analysis to mass spectrum of MS/MS in order to obtained a credible experiment result.This method is sensitive and accurate,it is suitable for determination of multifarious pesticide residues.展开更多
Objective:To compare the analgesic effect of Jin Ling Zi Powder(JLZ)and its two single herbs.Methods:The hot plate method was used to induce pain.Totally 36 mice were randomly divided into 6 groups by a complete rando...Objective:To compare the analgesic effect of Jin Ling Zi Powder(JLZ)and its two single herbs.Methods:The hot plate method was used to induce pain.Totally 36 mice were randomly divided into 6 groups by a complete random design,including control,model,aspirin(ASP,0.14 g/kg body weight),JLZ(14 g/kg body weight),Corydalis yanhusuo(YHS,14 g/kg body weight),and Toosendan Fructus(TF,14 g/kg body weight)groups,6 mice in each group.The mice in the control and model groups were given the same volume of saline,daily for 2 consecutive weeks.At 30,60,90,and 120 min after the last administration,the pain threshold of mice in each group was measured,and the improvement rate of pain threshold was calculated.Serum endogenous metabolites were analyzed by gas chromatography–mass spectrometry(GC–MS).Results:There was no statistical difference in pain threshold among groups before administration(P>0.05).After 2 weeks of administration,compared with the model group,the pain threshold in JLZ,YHS,TF and ASP groups were increased to varying degrees(P<0.05).JLZ had the best analgesic effect and was superior to YHS and TF groups.A total of 14 potential biomarkers were screened in serum data analysis and potential biomarkers levels were all reversed to different degrees after the treatment with JLZ and its single herbs.These potential biomarkers were mainly related to glyoxylate and dicarboxylate metabolism,glycine,serine and threonine metabolism,valine,leucine and isoleucine biosynthesis,aminoacyl-t RNA biosynthesis and inositol phosphate metabolism.Conclusions:The analgesic mechanism of JLZ and YHS was mainly due to the combination of glycine and its receptor,producing post-synaptic potential,reducing the excitability of neurons,and weakening the afferent effect of painful information.展开更多
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 cou- pled with time-of-flight mass spectrometry （GCxGC- TOFMS） 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 co- elution, which cannot be realized by conventional one-dimensional GC-MS. The GC×GC technique is especially effective for analyzing aromatics and low-to-middle- molecular-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×GC- TOFMS, showing its broad usefulness in petroleum geochemistry.
文摘In recent decades, biotechnology produced a growth of knowledge on the causes and mechanisms of metabolic diseases that have formed the basis for their study, diagnosis and treatment. Unfortunately, it is well known that the clinical features of metabolic diseases can manifest themselves with very different characteristics and escape early detection. Also, it is well known that the prognosis of many metabolic diseases is excellent if diagnosed and treated early. In this editorial we briefly summarized two groups of inherited metabolic diseases, the defects of cholesterol biosynthesis and those of bile acids. Both groups show variable clinical manifestations but some clinical signs and symptoms are common in both the defects of cholesterol and bile acids. The differential diagnosis can be made analyzing sterol profiles in blood and/or bile acids in blood and urine by chromatographic techniques(GC-MS and LC-MS/MS). Several defects of both biosynthetic pathways are treatable so early diagnosis is crucial. Unfortunately their diagnosis is made too late, due either to the clinical heterogeneity of the syndromes(severe, mild and very mild) that to the scarcity of scientific dissemination of these rare diseases. Therefore, the delay in diagnosis leads the patient to the medical observation when the disease has produced irreversible damages to the body. Here, we highlighted simple clinical and laboratory descriptions that can potentially make you to suspect a defect in cholesterol biosynthesis and/or bile acids, as well, we suggest appropriate request of the laboratory tests that along with common clinical features can help to diagnose these defects.
文摘In this report, gas chromatography-mass spectrometry (GC-MS) based non-targeted metabolomics is used to develop appropriate headspace solid phase microextractions (HS-SPME) to enhance the understanding of volatile complexity of flue-cured tobacco leaves. Non-targeted metabolic profiling of GC-MS shows that the extraction condition of HS-SPME at 100?C for 30 min provides a better metabolite profile than other extraction conditions tested. GC-MS and principal component analyses (PCA) show that among five types of fibers tested, 100 μm polydimethylsiloxane (PMDS), 65 μm polydimethylsiloxane/divinylbenzene (PMDS/DVB) and 75 μm carboxen/polydimethylsiloxane (CAR/ PMS) provide a better reproducible metabolite profile. Based on an appropriate PDMS extraction condition optimized, we use GC-MS analysis and PCA to compare metabolite profiles in flue-cured leaves of tobacco plants grown in North Carolina, India and Brazil, respectively. The resulting data of PCA show that the global metabolic profiles in North Carolina samples are separated from those in Brazil and India samples, two groups of which are characterized by a partially overlapped pattern. Several peaks that were differentially accumulated in samples were annotated to known metabolites by deconvolution analysis, such as norsolanadione, solavetivone and rishtin. Norsolanadione is detected only in Brazil samples. Solavetivone is detected in samples of India and Brazil but not in those of North Carolina. Rishtin is detected in samples of North Carolina and India but not in Brazil samples. These data indicate that not only can a non-targeted metabolic profiling approach enhance the understanding of volatile complexity, but also can identify marker volatile metabolites in tobacco leaves produced in different growth regions.
文摘Due to the harmful effect of free radical on physiological and pathological state of our body on one hand, and the increase of the fungal infection on the other hand, drug that can reduce free radical and inhibit fungal growth is needed. This work aims to evaluate the antioxidant and antifungal activities of the Ocimum gratissimum L. essential oils from center and west region of Cameroon. Essential oil was analyzed by GC （gas chromatography） and GC coupled with MS （mass spectrometry）. The antioxidant activities of essential oils were studied by the Diphenylpicrylhydrazyl method and the β-carotene bleaching test. The antifungal activities were assessed using micro-dilution technique for yeasts and agar dilution method for Aspergillus. Thymol and γ-terpinene, eugenol and thymol were the major compounds for Yaounde and Dschang, respectively. The scavenging capacity of sample from Dschang was higher than that of Yaounde. Also, the β-carotene bleaching tests of the sample from Dschang were better than that from Yaounde. The antifungal activity of the sample from Yaounde was higher than that from Dschang on yeasts and Aspergillus isolates, respectively. This work presents and compares the chemical composition, antioxidant and antifungal activity of Ocimum gratissimum essential oil from center and west region of Cameroon.
文摘To establish a new GC-MS/MS method for quantitative detection of 22 kinds of pesticide in fruit and vegetable including organic phosphorus,carbamate & pyrethrin etc.Working was performed by Xcalibur software with multitask mode.We Carried on qualitative and quantitative analysis to mass spectrum of MS/MS in order to obtained a credible experiment result.This method is sensitive and accurate,it is suitable for determination of multifarious pesticide residues.
文摘Objective:To compare the analgesic effect of Jin Ling Zi Powder(JLZ)and its two single herbs.Methods:The hot plate method was used to induce pain.Totally 36 mice were randomly divided into 6 groups by a complete random design,including control,model,aspirin(ASP,0.14 g/kg body weight),JLZ(14 g/kg body weight),Corydalis yanhusuo(YHS,14 g/kg body weight),and Toosendan Fructus(TF,14 g/kg body weight)groups,6 mice in each group.The mice in the control and model groups were given the same volume of saline,daily for 2 consecutive weeks.At 30,60,90,and 120 min after the last administration,the pain threshold of mice in each group was measured,and the improvement rate of pain threshold was calculated.Serum endogenous metabolites were analyzed by gas chromatography–mass spectrometry(GC–MS).Results:There was no statistical difference in pain threshold among groups before administration(P>0.05).After 2 weeks of administration,compared with the model group,the pain threshold in JLZ,YHS,TF and ASP groups were increased to varying degrees(P<0.05).JLZ had the best analgesic effect and was superior to YHS and TF groups.A total of 14 potential biomarkers were screened in serum data analysis and potential biomarkers levels were all reversed to different degrees after the treatment with JLZ and its single herbs.These potential biomarkers were mainly related to glyoxylate and dicarboxylate metabolism,glycine,serine and threonine metabolism,valine,leucine and isoleucine biosynthesis,aminoacyl-t RNA biosynthesis and inositol phosphate metabolism.Conclusions:The analgesic mechanism of JLZ and YHS was mainly due to the combination of glycine and its receptor,producing post-synaptic potential,reducing the excitability of neurons,and weakening the afferent effect of painful information.
