The objective of this study was to determine the differences of aroma and taste in three black sesame originsbefore and after processing via flavor and widely metabolomics.By analyzing the sensory characteristics and ...The objective of this study was to determine the differences of aroma and taste in three black sesame originsbefore and after processing via flavor and widely metabolomics.By analyzing the sensory characteristics and metabolites of raw and treated black sesame from China,Vietnam,and Myanmar,treated Chinese sesame have the most significant change in hardness after thermal processing,low viscosity and was easy to chew.The electronic nose could distinguish between raw and treated sesame due to the aroma distribution.The reason of treated sesame from China was“fragrant”is due to the highest content(2545.50μg/kg)of total pyrazines including 2,5-dimethylpyrazine,2-ethyl-5-methylpyrazine,2,3,5-trimethylpyrazine,3-ethyl-2,5-dimethylpyrazine.933 metabolites were detected via a wide targeted metabolomics in the taste of raw and treated sesame.Based on the analysis of metabolites related to bitterness,145 substances were selected.The main bitter contributors may be amino acids,dipeptides and organic acids.展开更多
The accurate and efficient measurement of small molecule disease markers for clinical diagnosis is of great importance.In this study,a quadrupole-linear ion trap(Q-LIT)tandem mass spectrometer was designed and built i...The accurate and efficient measurement of small molecule disease markers for clinical diagnosis is of great importance.In this study,a quadrupole-linear ion trap(Q-LIT)tandem mass spectrometer was designed and built in our laboratory.Target precursor ions were first selected in the quadrupole,and then injected,trapped,and fragmented simultaneously in the linear ion trap(LIT)to reduce the space charge effect,enrich the target product ions,and promote sensitivity.The targeted analytes were measured with selected reaction monitoring using a positive scan mode with electrospray ionization(ESI).Ions with a mass-to-charge ratio(m/z)ranging from 195 to 2022 were demonstrated.When scanning at 1218amu.s^(-1),unit resolution and an accuracy of higher than m/z 0.28 was obtained for m/z up to 2000.The dimensionless Mathieu parameter(q)value used in this study was 0.40 for collision-induced dissociation(CID),which was activated by resonance excitation.And an overall CID efficiency of 64%was achieved(activation time,50 ms).Guanidinoacetic acid(GAA)and creatine(CRE)were used as model compounds for small molecule clinical biomarkers.The limits of quantification were 1.0 and 0.2 nmol.L^(-1)for GAA and CRE,respectively.A total of 77 actual samples were successfully analyzed by the home-built ESI-Q-LIT tandem mass spectrometry system.The developed method can reduce matrix interference,minimize space charge effects,and avoid the chromatographic separation of complex samples to simplify the pretreatment process.This novel Q-LIT system is expected to be a good candidate for the determination of biomarkers in clinical diagnosis and therapeutics.展开更多
Government information sharing(GIS)refers to that act of required or provided for duty government information,commercial information and public welfare information,and it is a basic issue of government services.Howeve...Government information sharing(GIS)refers to that act of required or provided for duty government information,commercial information and public welfare information,and it is a basic issue of government services.However,the existing GIS has low transparency and is lack of flexibility between different departments.Aiming at such problems,this paper takes blockchain as a solusion,and systematically summarizes the development of digital GIS,the advantages and challenges of blockchain and its theoretical research and practical applications.Specifically,it reviews e-government interactive structure,big data and other solutions,analyses their imperfections,and puts forward blockchain-based solutions.The blockchain improves government service efficiency and data security,meanwhile it faces challenges in throughput and supervision.In order to meet these challenges,researchers propose solutions based on three data exchange scenarios:government-to-government,government-to-enterprise and government-toindividual.In addition to researches,blockchain-based GIS is put into use.The electronic licensing project of Nanjing(China)government is taken as an example to illustrate that blockchain has the ability to openly and securely verify,track,and exchange data,so as to improve management ability and public service level of government agencies.展开更多
基金Basic research business expenses(Y2023LM18)the Agricultural Science and Technology Innovation Project of the Chinese Academy of Agricultural Sciences(CAAS-ASTIP-2021-OCRI).
文摘The objective of this study was to determine the differences of aroma and taste in three black sesame originsbefore and after processing via flavor and widely metabolomics.By analyzing the sensory characteristics and metabolites of raw and treated black sesame from China,Vietnam,and Myanmar,treated Chinese sesame have the most significant change in hardness after thermal processing,low viscosity and was easy to chew.The electronic nose could distinguish between raw and treated sesame due to the aroma distribution.The reason of treated sesame from China was“fragrant”is due to the highest content(2545.50μg/kg)of total pyrazines including 2,5-dimethylpyrazine,2-ethyl-5-methylpyrazine,2,3,5-trimethylpyrazine,3-ethyl-2,5-dimethylpyrazine.933 metabolites were detected via a wide targeted metabolomics in the taste of raw and treated sesame.Based on the analysis of metabolites related to bitterness,145 substances were selected.The main bitter contributors may be amino acids,dipeptides and organic acids.
基金financially supported by the National Key R&D Program of China(2018YFF0212503,2019YFF0216303,and 2016YFF0200502)the National Natural Science Foundation of China(21927812)the Research Project of the National Institute of Metrology(AKY1934)。
文摘The accurate and efficient measurement of small molecule disease markers for clinical diagnosis is of great importance.In this study,a quadrupole-linear ion trap(Q-LIT)tandem mass spectrometer was designed and built in our laboratory.Target precursor ions were first selected in the quadrupole,and then injected,trapped,and fragmented simultaneously in the linear ion trap(LIT)to reduce the space charge effect,enrich the target product ions,and promote sensitivity.The targeted analytes were measured with selected reaction monitoring using a positive scan mode with electrospray ionization(ESI).Ions with a mass-to-charge ratio(m/z)ranging from 195 to 2022 were demonstrated.When scanning at 1218amu.s^(-1),unit resolution and an accuracy of higher than m/z 0.28 was obtained for m/z up to 2000.The dimensionless Mathieu parameter(q)value used in this study was 0.40 for collision-induced dissociation(CID),which was activated by resonance excitation.And an overall CID efficiency of 64%was achieved(activation time,50 ms).Guanidinoacetic acid(GAA)and creatine(CRE)were used as model compounds for small molecule clinical biomarkers.The limits of quantification were 1.0 and 0.2 nmol.L^(-1)for GAA and CRE,respectively.A total of 77 actual samples were successfully analyzed by the home-built ESI-Q-LIT tandem mass spectrometry system.The developed method can reduce matrix interference,minimize space charge effects,and avoid the chromatographic separation of complex samples to simplify the pretreatment process.This novel Q-LIT system is expected to be a good candidate for the determination of biomarkers in clinical diagnosis and therapeutics.
基金supported by Hainan Province Basic and Applied Basic Research Program(Natural Science Field)High-level Talent Project(Grant No.2019RC044).
文摘Government information sharing(GIS)refers to that act of required or provided for duty government information,commercial information and public welfare information,and it is a basic issue of government services.However,the existing GIS has low transparency and is lack of flexibility between different departments.Aiming at such problems,this paper takes blockchain as a solusion,and systematically summarizes the development of digital GIS,the advantages and challenges of blockchain and its theoretical research and practical applications.Specifically,it reviews e-government interactive structure,big data and other solutions,analyses their imperfections,and puts forward blockchain-based solutions.The blockchain improves government service efficiency and data security,meanwhile it faces challenges in throughput and supervision.In order to meet these challenges,researchers propose solutions based on three data exchange scenarios:government-to-government,government-to-enterprise and government-toindividual.In addition to researches,blockchain-based GIS is put into use.The electronic licensing project of Nanjing(China)government is taken as an example to illustrate that blockchain has the ability to openly and securely verify,track,and exchange data,so as to improve management ability and public service level of government agencies.