The effect of water deficit was determined on both in vitro and soil seedling as well as in cells in suspension of Agave americana L.In order to do the establishment of cells,the formation of callus was induced;for it...The effect of water deficit was determined on both in vitro and soil seedling as well as in cells in suspension of Agave americana L.In order to do the establishment of cells,the formation of callus was induced;for it two auxins were evaluated:2,4-dichlorophenoxyacetic acid(2,4-D)and 4-mino-3,5,6-trichloropicolinic acid(picloram)at three concentrations(0.25,0.5 and 0.75 mg L−1)in three explants(leaf,root and meristems)cultured in MS semisolid medium.The callogenesis response was related to the type and section of the explant,as well as the regulator used,and a cell suspension was established using 0.5 mg L−1 naphthaleneacetic acid(NAA)+0.5 mg L−1 Benzylaminopurine(BAP).Seedlings were exposed to polyethyleneglycol(15%and 30%w/v)with a water potential of−0.87 and−2.67 MPa,respectively,under soil conditions.Water stress was applied through restricted irrigation.Fresh weight,root system growth,and chlorophyll concentration were some of the parameters that were affected by the effect of water deficit on A.americana L.Chlorophyll concentration values were significantly decreased by 15 at 30%PEG(19.6 SPAD units)compared to the control treatment.In in vitro plants,the highest concentration of proline was found in the roots,being the treatment with 30%polyethylene glycol where the highest concentration of this osmoregulator was obtained(62.5 mg g−1 DW).Under restricted irrigation conditions,an increase in proline concentration was observed both in the aerial part(2.2μg 100 g−1 DW)and in the root system(1.8μg 100 g−1 DW).However,the concentrations found were approximately ten times greater,less than those found under in vitro conditions.Therefore,the accumulation of proline can be considered an indicator of stress in Agave Americana L.growth in vitro.展开更多
Two new spirostanol glycosides named agamenoside A and B, were isolated from the fermented leaves of Agave americana. Their structures were elucidated as (23S, 25R)-5a -spirostan-3b, 6a, 23-triol 3-O-a-L-rhamnopyrano...Two new spirostanol glycosides named agamenoside A and B, were isolated from the fermented leaves of Agave americana. Their structures were elucidated as (23S, 25R)-5a -spirostan-3b, 6a, 23-triol 3-O-a-L-rhamnopyranosyl-(13)- b-D-glucopyranosyl-(12)-[b-D- xylopyranosyl-(13)]-b-D-glucopyranosyl-(14)-b-D-galactopyranoside (1) and (25R)-5a-spiro- stan-3b, 6a-diol 3-O-b-D-glucopyranosyl-(12)-[ b-D-xylopyranosyl-(13)]- b-D-glucopyra- nosyl-(14)- b-D-galactopyranoside (2) by a combination of chemical and spectral methods.展开更多
A new minor pregnane glycoside was isolated from the fermented leaves of Agave americana. Its structure was elucidated as (20S)-5a-pregnane-3? 20-diol 20-O--D-glucopyrano- side (1) by spectral methods.
In this study,the fibers of invasive species Agave americana L.and Ricinus communis L.were successfully used for the first time as new sources to produce cytocompatible and highly crystalline cellulose nanofibers.Cell...In this study,the fibers of invasive species Agave americana L.and Ricinus communis L.were successfully used for the first time as new sources to produce cytocompatible and highly crystalline cellulose nanofibers.Cellulose nanofibers were obtained by two methods,based on either alkaline or acid hydrolysis.The morphology,chemical composition,and crystallinity of the obtained materials were characterized by scanning electron microscopy(SEM)together with energy-dispersive X-ray spectroscopy(EDX),dynamic light scattering(DLS),X-ray diffraction(XRD),and Fourier transform infrared(FTIR)spectroscopy.The crystallinity indexes(CIs)of the cellulose nanofibers extracted from A.americana and R.communis were very high(94.1%and 92.7%,respectively).Biological studies evaluating the cytotoxic effects of the prepared cellulose nanofibers on human embryonic kidney 293 T(HEK293 T)cells were also performed.The nanofibers obtained using the two different extraction methods were all shown to be cytocompatible in the concentration range assayed(i.e.,0-500μg/mL).Our results showed that the nanocellulose extracted from A.americana and R.communis fibers has high potential as a new renewable green source of highly crystalline cellulose-based cytocompatible nanomaterials for biomedical applications.展开更多
Two new spirostanol sapogenins named agavegenin A and B were isolated from the fermented leaves of Agave americana L. Their structures were elucidated as (23S, 25R)-5a- spirostan-3b, 6a, 11a, 23-tetraol (1) and (23S,...Two new spirostanol sapogenins named agavegenin A and B were isolated from the fermented leaves of Agave americana L. Their structures were elucidated as (23S, 25R)-5a- spirostan-3b, 6a, 11a, 23-tetraol (1) and (23S, 25S)-5a-spirostan-3b, 23, 27-triol (2) by spectral methods.展开更多
某铀尾矿区生长着大量美洲商陆（Phytolacca americana L.）,目前还未见美洲商陆耐受及富集铀相关蛋白质组学研究报道。为了找到铀耐受及富集表达相关蛋白,建立了铀尾矿区和对照区2种不同生境美洲商陆根系蛋白质组研究技术。通过全蛋白...某铀尾矿区生长着大量美洲商陆（Phytolacca americana L.）,目前还未见美洲商陆耐受及富集铀相关蛋白质组学研究报道。为了找到铀耐受及富集表达相关蛋白,建立了铀尾矿区和对照区2种不同生境美洲商陆根系蛋白质组研究技术。通过全蛋白质制备条件优化、2DE电泳条件摸索以及染色方法选择,得到了重现性好、分离效果和清晰度都很高的美洲商陆根系双向电泳差异凝胶图谱。经软件分析,筛选出了铀耐受及富集相关蛋白24个,上调表达11个、下调表达13个。展开更多
垂序商陆(Phytolacca americana L.)是我国首次发现的锰超富集植物。通过温室营养液培养实验,研究垂序商陆锰耐性与光合特性及叶绿素荧光参数的关系。结果表明,随着生长介质中锰浓度的升高,垂序商陆叶片的叶绿素a、叶绿素b和总叶绿素含...垂序商陆(Phytolacca americana L.)是我国首次发现的锰超富集植物。通过温室营养液培养实验,研究垂序商陆锰耐性与光合特性及叶绿素荧光参数的关系。结果表明,随着生长介质中锰浓度的升高,垂序商陆叶片的叶绿素a、叶绿素b和总叶绿素含量下降,净光合速率(Pn)和气孔导度(Gs)呈下降趋势,而胞间CO2浓度(Ci)却逐渐升高;叶绿素a/b值和蒸腾速率(Tr)在1 000μmol.L-1锰供应水平时达到最大值;叶片PSⅡ的最大量子产量(Fv/Fm)、PSⅡ有效光化学量子产量(EQY)和光合电子传递速率(ETR)呈下降趋势,而光化学淬灭系数(qP)和光合有效辐射(PAR)高于239μmol photons.m-.2s-1下的非光化学淬灭系数(NPQ)在5 000μmol.L-1锰供应水平时达到最大值。因此,垂序商陆在锰胁迫下可能具有一定的光合保护机制。展开更多
基金To CONACYT for the Master’s scholarship of Arnoldo Enrique Alfaro Corres(Scholarship No.621617).
文摘The effect of water deficit was determined on both in vitro and soil seedling as well as in cells in suspension of Agave americana L.In order to do the establishment of cells,the formation of callus was induced;for it two auxins were evaluated:2,4-dichlorophenoxyacetic acid(2,4-D)and 4-mino-3,5,6-trichloropicolinic acid(picloram)at three concentrations(0.25,0.5 and 0.75 mg L−1)in three explants(leaf,root and meristems)cultured in MS semisolid medium.The callogenesis response was related to the type and section of the explant,as well as the regulator used,and a cell suspension was established using 0.5 mg L−1 naphthaleneacetic acid(NAA)+0.5 mg L−1 Benzylaminopurine(BAP).Seedlings were exposed to polyethyleneglycol(15%and 30%w/v)with a water potential of−0.87 and−2.67 MPa,respectively,under soil conditions.Water stress was applied through restricted irrigation.Fresh weight,root system growth,and chlorophyll concentration were some of the parameters that were affected by the effect of water deficit on A.americana L.Chlorophyll concentration values were significantly decreased by 15 at 30%PEG(19.6 SPAD units)compared to the control treatment.In in vitro plants,the highest concentration of proline was found in the roots,being the treatment with 30%polyethylene glycol where the highest concentration of this osmoregulator was obtained(62.5 mg g−1 DW).Under restricted irrigation conditions,an increase in proline concentration was observed both in the aerial part(2.2μg 100 g−1 DW)and in the root system(1.8μg 100 g−1 DW).However,the concentrations found were approximately ten times greater,less than those found under in vitro conditions.Therefore,the accumulation of proline can be considered an indicator of stress in Agave Americana L.growth in vitro.
基金This work was financially supported by the National Natural Science Foundation of China (NSFC) (39969005)The authors wish to thanks the members of analytic group of Laboratory of Phytochemistry,Kunming Institute of Botany for spectral measurements.
文摘Two new spirostanol glycosides named agamenoside A and B, were isolated from the fermented leaves of Agave americana. Their structures were elucidated as (23S, 25R)-5a -spirostan-3b, 6a, 23-triol 3-O-a-L-rhamnopyranosyl-(13)- b-D-glucopyranosyl-(12)-[b-D- xylopyranosyl-(13)]-b-D-glucopyranosyl-(14)-b-D-galactopyranoside (1) and (25R)-5a-spiro- stan-3b, 6a-diol 3-O-b-D-glucopyranosyl-(12)-[ b-D-xylopyranosyl-(13)]- b-D-glucopyra- nosyl-(14)- b-D-galactopyranoside (2) by a combination of chemical and spectral methods.
基金supported by the National Natulal Science Foundation of China(NSFC)(39969005).
文摘A new minor pregnane glycoside was isolated from the fermented leaves of Agave americana. Its structure was elucidated as (20S)-5a-pregnane-3? 20-diol 20-O--D-glucopyrano- side (1) by spectral methods.
基金the Programa de Cooperación Territorial INTERREG V-A MAC 2014-2020 and Inv2Mac Project(MAC/4.6d/229)the partial support of FCT-Funda??o para a Ciência e a Tecnologia(Base Fund UIDB/00674/2020)+1 种基金ARDITI-Agência Regional para o Desenvolvimento da Investiga??o Tecnologia e Inova??o supported the study through the project M1420-01-0145FEDER-000005-CQM+(Madeira 14-20 Program)the Postdoc Grant(M1420-09-5369-FSE-000001,002458/2015/132)for Carla S.ALVES is also acknowledged。
文摘In this study,the fibers of invasive species Agave americana L.and Ricinus communis L.were successfully used for the first time as new sources to produce cytocompatible and highly crystalline cellulose nanofibers.Cellulose nanofibers were obtained by two methods,based on either alkaline or acid hydrolysis.The morphology,chemical composition,and crystallinity of the obtained materials were characterized by scanning electron microscopy(SEM)together with energy-dispersive X-ray spectroscopy(EDX),dynamic light scattering(DLS),X-ray diffraction(XRD),and Fourier transform infrared(FTIR)spectroscopy.The crystallinity indexes(CIs)of the cellulose nanofibers extracted from A.americana and R.communis were very high(94.1%and 92.7%,respectively).Biological studies evaluating the cytotoxic effects of the prepared cellulose nanofibers on human embryonic kidney 293 T(HEK293 T)cells were also performed.The nanofibers obtained using the two different extraction methods were all shown to be cytocompatible in the concentration range assayed(i.e.,0-500μg/mL).Our results showed that the nanocellulose extracted from A.americana and R.communis fibers has high potential as a new renewable green source of highly crystalline cellulose-based cytocompatible nanomaterials for biomedical applications.
文摘Two new spirostanol sapogenins named agavegenin A and B were isolated from the fermented leaves of Agave americana L. Their structures were elucidated as (23S, 25R)-5a- spirostan-3b, 6a, 11a, 23-tetraol (1) and (23S, 25S)-5a-spirostan-3b, 23, 27-triol (2) by spectral methods.
文摘针对目前国内锰超富集植物商陆属(Phytolacca)植物名称混乱的状态,在重新审查锰超富集植物——商陆(Phytolacca acinosa Roxb.)的野外标本和温室培养植物的基础上,比对中国科学院昆明植物所标本馆的腊叶标本,并查阅相关文献资料,以期正确认定锰超富集累植物的学名。结果表明,湘潭锰矿尾矿废弃地原生的锰超富集植物实为垂序商陆(Phytolacca americana L.),国内外相关研究论文中出现的商陆和美洲商陆实为垂序商陆的同物异名。这一植物名称的认定,将对避免锰超富集植物研究重复进行、保证相关研究正常有序开展具有重要意义。
文摘某铀尾矿区生长着大量美洲商陆（Phytolacca americana L.）,目前还未见美洲商陆耐受及富集铀相关蛋白质组学研究报道。为了找到铀耐受及富集表达相关蛋白,建立了铀尾矿区和对照区2种不同生境美洲商陆根系蛋白质组研究技术。通过全蛋白质制备条件优化、2DE电泳条件摸索以及染色方法选择,得到了重现性好、分离效果和清晰度都很高的美洲商陆根系双向电泳差异凝胶图谱。经软件分析,筛选出了铀耐受及富集相关蛋白24个,上调表达11个、下调表达13个。
