[Objectives]To establish an efficient and environmentally friendly separation and purification method for the large-scale preparation of the major active components-eleutherol,eleutherine,and isoeleutherine-from the e...[Objectives]To establish an efficient and environmentally friendly separation and purification method for the large-scale preparation of the major active components-eleutherol,eleutherine,and isoeleutherine-from the ethnomedicinal plant Eleutherine americana Merr.et K.Heyne.[Methods]The sample of E.americana bulbs was initially extracted with ethanol,followed by three successive extractions with ethyl acetate-water(2:1,V/V)to obtain the target component-enriched fraction.Eight solvent systems were systematically optimized,and a mixture of petroleum ether-ethyl acetate-ethanol-water(5:5:6:4,V/V/V/V)was identified as the optimal solvent system for high-speed counter-current chromatography(HSCCC)separation under conditions of 900 rpm,2 mL/min,and 35℃.The crude HSCCC product was further purified by silica gel column chromatography(200-300 mesh)using gradient elution with a solvent system of n-hexane-dichloromethane-ethyl acetate(varying from 10:5:1 to 4:5:1,V/V/V).UPLC-PDA(Agilent SB-C_(18)column)and nuclear magnetic resonance spectroscopy(600 MHz)were comprehensively employed to assess compound purity and confirm molecular structures.[Results]An optimized technique integrating HSCCC and silica gel column chromatography was established,successfully enabling the large-scale preparation of three bioactive components:eleutherol(purity 99%),eleutherine(purity 98%),and isoeleutherine(purity 98%).Structural identification results were consistent with those reported in the literature.Compared to traditional methods,the new approach demonstrated improved separation efficiency and reduced solvent consumption.[Conclusions]The combined separation method utilizing HSCCC and silica gel column chromatography established in this study demonstrates notable advantages,including high efficiency,environmental friendliness,and cost-effectiveness,enabling the large-scale preparation of the three major active components from E.americana.This approach outperforms conventional methods by offering higher separation efficiency,reduced solvent consumption,and superior product purity,providing a robust technical solution for the development and utilization of bioactive compounds from E.americana.Moreover,it offers a novel methodological reference for the isolation and purification of other natural products.展开更多
[Objectives]To isolate and analyze alkaloids in Fructus Hordei Germinatus.[Methods]The alkaloids in the Fructus Hordei Germinatus were extracted by ultrasonic technology,and analyzed by the ultra-performance liquid ch...[Objectives]To isolate and analyze alkaloids in Fructus Hordei Germinatus.[Methods]The alkaloids in the Fructus Hordei Germinatus were extracted by ultrasonic technology,and analyzed by the ultra-performance liquid chromatography tandem mass spectrometry(UPLC-MS/MS) technique.[Results] According to the mass spectrometry information,compared with the literature reports,the possible structures of seven alkaloids in the Fructus Hordei Germinatus could be inferred.Compounds 1,2 and 3 were organic amine alkaloids,respectively tyramine and N-methyltyramine,hordenine,compounds 4,5,6 and 7 were indole alkaloids,respectively,tryptamine,gramine,harmine,and bufotenidine.The alkaloids in the Fructus Hordei Germinatus were separated by preparative high performance liquid chromatography(p HPLC) technique,a compound was obtained and identified by UPLC-MS/MS and nuclear magnetic resonance(NMR) technique as hordenine.[Conclusions]This experiment is expected to lay a foundation for the development of alkaloids in the Fructus Hordei Germinatus.展开更多
[Objectives]To prepare plumbagin nanomicelle(PLB-N)in-situ gel,and optimize the formulation and process.[Methods]PLB-N was prepared by self-assembly method,and the optimal formulation of PLB-N in-situ gel was determin...[Objectives]To prepare plumbagin nanomicelle(PLB-N)in-situ gel,and optimize the formulation and process.[Methods]PLB-N was prepared by self-assembly method,and the optimal formulation of PLB-N in-situ gel was determined by orthogonal experiment design and single factor method.[Results]The optimal preparation process for PLB-N was a drug to lipid ratio of 1:3,a Tween 80 content of 5%,an ethanol content of 7.5%of the hydration medium,a magnetic stirring speed of 2200 rpm,a stirring time of 30 min,and an ultrasound time of 10 min.The optimal formulation of PLB-N in-situ gel was 22%of poloxamer 407,6%of poloxamer 188,and 1:1 of PLB-N to water.The encapsulation efficiency of PLB-N prepared with the optimal formula was(95.8%±0.4%),and the average particle size was(75.19±1.14)nm,and the Zeta potential was(-20.73±1.19)mv.[Conclusions]PLB-N in-situ gel had stable and reliable preparation process,uniform content,and broad application prospects.展开更多
[Objectives] To study in vitro antioxidant activity of extracts from Eleutherine plicata Herb by different extraction methods.[Methods]1,1-diphenyl-2-picrylhydrazyl( DPPH) free radical scavenging method,2,2'-Azino...[Objectives] To study in vitro antioxidant activity of extracts from Eleutherine plicata Herb by different extraction methods.[Methods]1,1-diphenyl-2-picrylhydrazyl( DPPH) free radical scavenging method,2,2'-Azinobis( 3-ehtylbenzothiazolin-6-sulfnic acid) diammonium salt( ABTS) free radical scavenging method,and iron ion reduction ability determination method were applied to measure the extracts of Eleutherine plicata Herb by ethanol extraction,water extraction,and ethanol extraction after water extraction,and comparison was made with positive control Vc( vitamin C). [Results]The ethanol extract,water extract,and ethanol extract after water extraction of Eleutherine plicata Herb had a high DPPH free radical,ABTS free radical scavenging activity,and reducing activity. [Conclusions]E. plicata Herb is a natural antioxidant with high potential.展开更多
[Objectives] To study the original plant,traits and microscopic identification for Yi medicinal material Campanula colorata,and provide experimental data for its identification and medicinal use. [Methods] Plant ident...[Objectives] To study the original plant,traits and microscopic identification for Yi medicinal material Campanula colorata,and provide experimental data for its identification and medicinal use. [Methods] Plant identification,trait identification,powder identification and paraffin slice identification were adopted in the study. [Results]It was found that the original plant of Campanula colorata was characterized by stiff hairs,slightly thicker root than stem,serrated leaf margin,tubular bell-shaped corolla and blue-purple color; traits were featured by odorlessness,and bitter taste after slight sweetness; the microscopic identification characteristics were that the laticifer was sporadic,containing reddish brown or yellow brown materials,and the oil droplets and nonglandular hairs were common. [Conclusions] The original plant,trait and microscopic identification characteristics were obvious for Yi medicinal material Campanula colorata,which could provide a reference for developing quality standards and identifying the original plant of Campanula colorata,and provide the basis for further research and development.展开更多
Assembling an axial rotor and a stator at centrifugal compressor upstream to build an axial-radial combined compressor could achieve high pressure ratio and efficiency by appropriate size augment.Then upstream potenti...Assembling an axial rotor and a stator at centrifugal compressor upstream to build an axial-radial combined compressor could achieve high pressure ratio and efficiency by appropriate size augment.Then upstream potential flow and wake effect appear at centrifugal impeller inlet.In this paper,the axial-radial compressor is unsteadily simulated by three-dimensional Reynolds averaged Navier-Stokes equations with uniform and circumferential distorted total pressure inlet condition to investigate upstream effect on radial rotor.The results show that spanwise nonuniform total pressure distribution is generated and radial and circumferential combined distortion is formed at centrifugal rotor inlet.The upstream stator wake deflects to rotor rotation direction and decreases with blade span increases.Circumferential distortion causes different separated flow formations at different pitch positions.The tip leakage vortex is suppressed in centrifugal blade passages.Under distorted inlet condition,flow direction of centrifugal impeller leading edge upstream varies evidently near hub and shroud but varies slightly at mid-span.In addition,compressor stage inlet distortion produces remarkable effect on blade loading of centrifugal blade both along chordwise and pitchwise.展开更多
基金Supported by Natural Science Foundation of Tibet Autonomous Region,Science and Technology Department of Tibet(XZ202501ZR0118).
文摘[Objectives]To establish an efficient and environmentally friendly separation and purification method for the large-scale preparation of the major active components-eleutherol,eleutherine,and isoeleutherine-from the ethnomedicinal plant Eleutherine americana Merr.et K.Heyne.[Methods]The sample of E.americana bulbs was initially extracted with ethanol,followed by three successive extractions with ethyl acetate-water(2:1,V/V)to obtain the target component-enriched fraction.Eight solvent systems were systematically optimized,and a mixture of petroleum ether-ethyl acetate-ethanol-water(5:5:6:4,V/V/V/V)was identified as the optimal solvent system for high-speed counter-current chromatography(HSCCC)separation under conditions of 900 rpm,2 mL/min,and 35℃.The crude HSCCC product was further purified by silica gel column chromatography(200-300 mesh)using gradient elution with a solvent system of n-hexane-dichloromethane-ethyl acetate(varying from 10:5:1 to 4:5:1,V/V/V).UPLC-PDA(Agilent SB-C_(18)column)and nuclear magnetic resonance spectroscopy(600 MHz)were comprehensively employed to assess compound purity and confirm molecular structures.[Results]An optimized technique integrating HSCCC and silica gel column chromatography was established,successfully enabling the large-scale preparation of three bioactive components:eleutherol(purity 99%),eleutherine(purity 98%),and isoeleutherine(purity 98%).Structural identification results were consistent with those reported in the literature.Compared to traditional methods,the new approach demonstrated improved separation efficiency and reduced solvent consumption.[Conclusions]The combined separation method utilizing HSCCC and silica gel column chromatography established in this study demonstrates notable advantages,including high efficiency,environmental friendliness,and cost-effectiveness,enabling the large-scale preparation of the three major active components from E.americana.This approach outperforms conventional methods by offering higher separation efficiency,reduced solvent consumption,and superior product purity,providing a robust technical solution for the development and utilization of bioactive compounds from E.americana.Moreover,it offers a novel methodological reference for the isolation and purification of other natural products.
基金Supported by Innovating Research Program of Postgraduates of Southwest Minzu University in 2017(CX2017SZ086)
文摘[Objectives]To isolate and analyze alkaloids in Fructus Hordei Germinatus.[Methods]The alkaloids in the Fructus Hordei Germinatus were extracted by ultrasonic technology,and analyzed by the ultra-performance liquid chromatography tandem mass spectrometry(UPLC-MS/MS) technique.[Results] According to the mass spectrometry information,compared with the literature reports,the possible structures of seven alkaloids in the Fructus Hordei Germinatus could be inferred.Compounds 1,2 and 3 were organic amine alkaloids,respectively tyramine and N-methyltyramine,hordenine,compounds 4,5,6 and 7 were indole alkaloids,respectively,tryptamine,gramine,harmine,and bufotenidine.The alkaloids in the Fructus Hordei Germinatus were separated by preparative high performance liquid chromatography(p HPLC) technique,a compound was obtained and identified by UPLC-MS/MS and nuclear magnetic resonance(NMR) technique as hordenine.[Conclusions]This experiment is expected to lay a foundation for the development of alkaloids in the Fructus Hordei Germinatus.
基金Supported by Special Fund for Basic Scientific Research Business in Central Universities(2019NYB31)Scientific Research Funded Project of Southwest Minzu University(2023KYZZ06N).
文摘[Objectives]To prepare plumbagin nanomicelle(PLB-N)in-situ gel,and optimize the formulation and process.[Methods]PLB-N was prepared by self-assembly method,and the optimal formulation of PLB-N in-situ gel was determined by orthogonal experiment design and single factor method.[Results]The optimal preparation process for PLB-N was a drug to lipid ratio of 1:3,a Tween 80 content of 5%,an ethanol content of 7.5%of the hydration medium,a magnetic stirring speed of 2200 rpm,a stirring time of 30 min,and an ultrasound time of 10 min.The optimal formulation of PLB-N in-situ gel was 22%of poloxamer 407,6%of poloxamer 188,and 1:1 of PLB-N to water.The encapsulation efficiency of PLB-N prepared with the optimal formula was(95.8%±0.4%),and the average particle size was(75.19±1.14)nm,and the Zeta potential was(-20.73±1.19)mv.[Conclusions]PLB-N in-situ gel had stable and reliable preparation process,uniform content,and broad application prospects.
基金Supported by Science and Technology Project of Sichuan Province(2015-JY0226)
文摘[Objectives] To study in vitro antioxidant activity of extracts from Eleutherine plicata Herb by different extraction methods.[Methods]1,1-diphenyl-2-picrylhydrazyl( DPPH) free radical scavenging method,2,2'-Azinobis( 3-ehtylbenzothiazolin-6-sulfnic acid) diammonium salt( ABTS) free radical scavenging method,and iron ion reduction ability determination method were applied to measure the extracts of Eleutherine plicata Herb by ethanol extraction,water extraction,and ethanol extraction after water extraction,and comparison was made with positive control Vc( vitamin C). [Results]The ethanol extract,water extract,and ethanol extract after water extraction of Eleutherine plicata Herb had a high DPPH free radical,ABTS free radical scavenging activity,and reducing activity. [Conclusions]E. plicata Herb is a natural antioxidant with high potential.
基金Supported by National Science and Technology Support Program(2015BAC05-B02)Sichuan Science and Technology Support Program(2015SZ0034)+1 种基金Education and Teaching Research and Reform Project of Southwest University for Nationalities(2015)National Development Project for Central Universities-Southwest University for Nationalities(2016NGJPY11)
文摘[Objectives] To study the original plant,traits and microscopic identification for Yi medicinal material Campanula colorata,and provide experimental data for its identification and medicinal use. [Methods] Plant identification,trait identification,powder identification and paraffin slice identification were adopted in the study. [Results]It was found that the original plant of Campanula colorata was characterized by stiff hairs,slightly thicker root than stem,serrated leaf margin,tubular bell-shaped corolla and blue-purple color; traits were featured by odorlessness,and bitter taste after slight sweetness; the microscopic identification characteristics were that the laticifer was sporadic,containing reddish brown or yellow brown materials,and the oil droplets and nonglandular hairs were common. [Conclusions] The original plant,trait and microscopic identification characteristics were obvious for Yi medicinal material Campanula colorata,which could provide a reference for developing quality standards and identifying the original plant of Campanula colorata,and provide the basis for further research and development.
基金supported by Chinese Specialized Research Fund for the Doctoral Program of Higher Education (20101101110009)
文摘Assembling an axial rotor and a stator at centrifugal compressor upstream to build an axial-radial combined compressor could achieve high pressure ratio and efficiency by appropriate size augment.Then upstream potential flow and wake effect appear at centrifugal impeller inlet.In this paper,the axial-radial compressor is unsteadily simulated by three-dimensional Reynolds averaged Navier-Stokes equations with uniform and circumferential distorted total pressure inlet condition to investigate upstream effect on radial rotor.The results show that spanwise nonuniform total pressure distribution is generated and radial and circumferential combined distortion is formed at centrifugal rotor inlet.The upstream stator wake deflects to rotor rotation direction and decreases with blade span increases.Circumferential distortion causes different separated flow formations at different pitch positions.The tip leakage vortex is suppressed in centrifugal blade passages.Under distorted inlet condition,flow direction of centrifugal impeller leading edge upstream varies evidently near hub and shroud but varies slightly at mid-span.In addition,compressor stage inlet distortion produces remarkable effect on blade loading of centrifugal blade both along chordwise and pitchwise.
