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1.
Int J Biol Macromol ; 256(Pt 2): 128233, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38040166

RESUMEN

In this work, we report an environmentally friendly renewable nanocomposite magnetic lignin-based palladium nanoparticles (Fe3O4-lignin@Pd-NPs) for efficient wastewater treatment by decorating palladium nanoparticles without using any toxic reducing agents on the magnetic lignin abstracted from Poplar. The structure of composite Fe3O4-lignin@Pd-NPs was unambiguously confirmed by XRD, SEM, TEM, EDS, FTIR, and Zeta potential. After systematic evaluation of the use and efficiency of the composite to remove toxic organic dyes in wastewater, some promising results were observed as follows: Fe3O4-lignin@Pd-NPs exhibits highly active and efficient performance in the removal of toxic methylene blue (MB) (up to 99.8 %) wastewater in 2 min at different concentrations of MB and different pH values. Moreover, except for toxic MB, the other organic dyes including Rhodamine B (RhB), Rhodamine 6G (Rh6G), and Methyl Orange (MO) can also be removed efficiently by the composite. Finally, the easily recovered composite Fe3O4-lignin@Pd-NPs exhibits well stability and reusability, and catalytic efficiency is maintained well after ten cycles. In conclusion, the lignin-based magnetism Pd composite exhibits powerful potential practical application in industrial wastewater treatment.


Asunto(s)
Nanopartículas del Metal , Nanocompuestos , Purificación del Agua , Lignina , Nanopartículas del Metal/química , Paladio/química , Aguas Residuales , Colorantes
2.
Nucleic Acids Res ; 51(2): 619-630, 2023 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-36546827

RESUMEN

Jasmonic acid (JA) signaling plays a pivotal role in plant development and defense. MYC2 is a master transcription factor in JA signaling, and was found to be phosphorylated and negatively regulated by MAP kinase and receptor-like kinase. However, the kinases that positively regulate MYC2 through phosphorylation and promote MYC2-mediated activation of JA response have not been identified. Here, we identified CK2 as a kinase that phosphorylates MYC2 and thus regulates the JA signaling. CK2 holoenzyme can interact with MYC2 using its regulatory subunits and phosphorylate MYC2 at multiple sites with its catalytic subunits. Inhibition of CK2 activity in a dominant-negative plant line, CK2mut, repressed JA response. On the other hand, increasing CK2 activity by overexpression of CKB4, a regulatory subunit gene of CK2, enhanced JA response in a MYC2-dependent manner. Substitution of the Ser and Thr residues at phosphorylation sites of MYC2 by CK2 with Ala impaired MYC2 function in activating JA response. Further investigations evidenced that CK2 facilitated the JA-induced increase of MYC2 binding to the promoters of JA-responsive genes in vivo. Our study demonstrated that CK2 plays a positive role in JA signaling, and reveals a previously undiscovered mechanism that regulates MYC2 function.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice , Quinasa de la Caseína II , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/genética , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/metabolismo , Ciclopentanos/metabolismo , Regulación de la Expresión Génica de las Plantas , Fosfotransferasas/genética , Quinasa de la Caseína II/metabolismo
3.
Org Lett ; 24(45): 8283-8288, 2022 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-36331137

RESUMEN

In this work, we successfully explored an unexpected dehydrogenation triggered by Pd/Cu-catalyzed C(sp3)-H arylation and intramolecular C-N coupling of amides to synthesize the bioactive 1,2-dihydroquinoline scaffold with good regioselectivity and good compatibility of functional groups. This strategy provides an alternative route to realize molecular complexity and diversity from simple and readily available molecules via multiple C-H bond activation. Preliminary mechanistic studies demonstrated that ß,γ-dehydrogenation is triggered by the arylation of the C(sp3)-H bond and the intramolecular C-N coupling.


Asunto(s)
Amidas , Paladio , Amidas/química , Paladio/química , Catálisis , Estructura Molecular
4.
Org Lett ; 21(6): 1668-1671, 2019 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-30801191

RESUMEN

In this letter, we successfully explored a cascade Pd/Cu-catalyzed intermolecular C(sp3)-H arylation of amides and intramolecular C-N coupling reaction. This method provides a one-pot strategy to synthesize 3,4-2 H-quinolinone with good regioselectivity of C-H arylation and C-N coupling from C-I and C-X bonds from readily available starting materials.

5.
Arch Pharm Res ; 41(12): 1162-1169, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30378038

RESUMEN

Four new acylated triterpene glycosides with aliphatic chains (4-7) as well as five known triterpenoids were isolated from the flower buds of Staphylea bumalda with bioassay guidance. Their structures were determined on the basis of spectral techniques, including IR, 1D and 2D NMR, and HR-APCI-MS. Most compounds (except 8) were isolated from S. bumalda for the first time. Additionally, the neuroprotective effects of 1 and 4-9 on suckling rat primary cultured hippocampal neurons against H2O2-induced injury were evaluated in vitro. The four new triterpenoids (4-7) showed neuroprotective effects, which increased the cell viability to over 74% at different concentrations, which was higher than the negative control (59%), while compounds 1 and 8-9 exhibited cytotoxic activity.


Asunto(s)
Glicósidos/farmacología , Hipocampo/efectos de los fármacos , Peróxido de Hidrógeno/antagonistas & inhibidores , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Triterpenos/farmacología , Animales , Flores/química , Glicósidos/química , Glicósidos/aislamiento & purificación , Hipocampo/patología , Peróxido de Hidrógeno/farmacología , Magnoliopsida/química , Neuronas/patología , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/aislamiento & purificación , Ratas , Ratas Sprague-Dawley , Triterpenos/química , Triterpenos/aislamiento & purificación
6.
Molecules ; 22(11)2017 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-29149016

RESUMEN

Five new oleanane-type saponins, named ligushicosides A-E, and three known oleanane-type saponins were isolated from the roots of Ligulariopsis shichuana. Their structures were established by a combination of spectroscopic techniques, including 1D and 2D NMR and high resolution electrospray ionization mass spectroscopy (HR-ESI-MS). Furthermore, all isolates were evaluated for their yeast α-glucosidase inhibitory effects and exhibited potent inhibition against α-glucosidase, while compounds 1 and 2 showed excellent inhibitory activities. The 3-O-glycoside moiety in oleanane-type saponin is important for the α-glucosidase inhibitory effects.


Asunto(s)
Inhibidores de Glicósido Hidrolasas/química , Inhibidores de Glicósido Hidrolasas/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Raíces de Plantas/química , Saponinas/química , Saponinas/farmacología , Activación Enzimática/efectos de los fármacos , Hidrólisis , Espectroscopía de Resonancia Magnética , Estructura Molecular , Relación Estructura-Actividad , alfa-Glucosidasas/química
7.
Plant Physiol Biochem ; 109: 240-247, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27750098

RESUMEN

Protein kinase CK2, which consists of two α and two ß subunits, plays an essential role in plant development and is implicated in plant responses to abiotic stresses, including salt and heat. However, the function of CK2 in response to heavy metals such as cadmium (Cd) has not yet been established. In this study, the transgenic line CKB4ox, which overexpresses CKB4 encoding the CK2ß subunit and has elevated CK2 activity, was used to investigate the potential role of CK2 in response to Cd stress in Arabidopsis thaliana. Under Cd stress, CKB4ox showed reduced root growth and biomass accumulation as well as decreased chlorophyll and proline contents compared with wild type. Furthermore, increased Cd accumulation and a higher H2O2 content were found in CKB4ox, possibly contributing to the inhibition of CKB4ox growth under Cd stress. Additionally, altered levels of Cd and H2O2 were found to be associated with decreased expression of genes involved in Cd efflux, Cd sequestration and H2O2 scavenging. Taken together, these results suggest that elevated expression of CKB4 and increased CK2 activity enhance the sensitivity of plants to Cd stress by affecting Cd and H2O2 accumulation, including the modulation of genes involved in Cd transport and H2O2 scavenging. This study provides direct evidence for the involvement of plant CK2 in the response to Cd stress.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Cadmio/farmacocinética , Cadmio/toxicidad , Quinasa de la Caseína II/metabolismo , Peróxido de Hidrógeno/metabolismo , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Proteínas de Arabidopsis/genética , Transporte Biológico Activo/genética , Quinasa de la Caseína II/genética , Clorofila/metabolismo , Regulación del Desarrollo de la Expresión Génica , Regulación Enzimológica de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Plantas Modificadas Genéticamente , Prolina/metabolismo , Subunidades de Proteína , Estrés Fisiológico
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(3): 896-902, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27400545

RESUMEN

Human telomeric G-quadruplex is a four-stranded structure folded by guanines (G) via Hoogsteen hydrogen bonding. The ligands which stabilize the G-quadruplex are often telomerase inhibitors and may become antitumor agents. Here, the interaction between a lignan derivative liliflorin A and human telomeric sequence dGGG (TTAGGG)3G-quadruplex HTG21 were examined by CD, FRET, and NMR spectroscopic methods. In addition, Molecular Docking was used to study the binding of liliflorin A to dTAGGG (TTAGGG)3 G-quadruplex HTG23. The CD data showed that liliflorin A enhanced HTG21 T(m). The T(m) value of G-quadruplex was enhanced 3.2 degrees C by 4.0 µmol x L(-1) liliflorin A in FRET. The NMR spectra of HTG21 showed vivid alteration after reacting with liliflorin A in 3 hours. Molecular Docking suggested liliflorin A bound to the wide groove of HTG23 at G9, G10, G16 and G17. Liliflorin A was the first lignan derivative that could stabilize HTG21 selectively and provided a new candidate for antitumor drug design targeting on human telomeric G-quadruplex.


Asunto(s)
G-Cuádruplex , Lignanos/química , Análisis Espectral , Telómero/química , Antineoplásicos , Inhibidores Enzimáticos , Guanina , Humanos , Enlace de Hidrógeno , Ligandos , Simulación del Acoplamiento Molecular
9.
Plant Cell Rep ; 35(5): 1071-80, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26883224

RESUMEN

KEY MESSAGE: Arabidopsis CK2 α4 subunit regulates the primary root and hypocotyl elongation, lateral root formation, cotyledon expansion, rosette leaf initiation and growth, flowering, and anthocyanin biosynthesis. Casein kinase 2 (CK2) is a conserved tetrameric kinase composed of two α and two ß subunits. The inhibition of CK2 activity usually results in severe developmental deficiency. Four genes (CKA1-CKA4) encode CK2 α subunit in Arabidopsis. Single mutations of CKA1, CKA2, and CKA3 do not affect the normal growth of Arabidopsis, while the cka1 cka2 cka3 triple mutants are defective in cotyledon and hypocotyl growth, lateral root development, and flowering. The inhibition of CKA4 expression in cka1 cka2 cka3 background further reduces the number of lateral roots and delays the flowering time. Here, we report the characterization of a novel knockout mutant of CKA4, which exhibits various developmental defects including reduced primary root and hypocotyl elongation, increased lateral root density, delayed cotyledon expansion, retarded rosette leaf initiation and growth, and late flowering. The examination of the cellular basis for abnormal root development of this mutant revealed reduced root meristem cells with enhanced RETINOBLASTOMA-RELATED (RBR) expression that promotes cell differentiation in root meristem. Moreover, this cka4-2 mutant accumulates higher anthocyanin in the aerial part and shows an increased expression of anthocyanin biosynthetic genes, suggesting a novel role of CK2 in modulating anthocyanin biosynthesis. In addition, the complementation test using primary root elongation assay as a sample confirms that the changed phenotypes of this cka4-2 mutant are due to the lack of CKA4. Taken together, this study reveals an essential role of CK2 α4 subunit in multiple developmental processes in Arabidopsis.


Asunto(s)
Antocianinas/metabolismo , Arabidopsis/enzimología , Quinasa de la Caseína II/metabolismo , Regulación de la Expresión Génica de las Plantas , Arabidopsis/citología , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Quinasa de la Caseína II/genética , Cotiledón/citología , Cotiledón/enzimología , Cotiledón/genética , Cotiledón/crecimiento & desarrollo , Flores/citología , Flores/enzimología , Flores/genética , Flores/crecimiento & desarrollo , Genes Reporteros , Hipocótilo/citología , Hipocótilo/enzimología , Hipocótilo/genética , Hipocótilo/crecimiento & desarrollo , Mutación , Fenotipo , Hojas de la Planta/citología , Hojas de la Planta/enzimología , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Raíces de Plantas/citología , Raíces de Plantas/enzimología , Raíces de Plantas/genética , Raíces de Plantas/crecimiento & desarrollo , Plantones/citología , Plantones/enzimología , Plantones/genética , Plantones/crecimiento & desarrollo , Alineación de Secuencia
10.
PLoS One ; 10(6): e0131599, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26121399

RESUMEN

Nitric oxide (NO) has been shown to play an important role in the plant response to biotic and abiotic stresses in Arabidopsis mutants with lower or higher levels of endogenous NO. The exogenous application of NO donors or scavengers has also suggested an important role for NO in plant defense against environmental stress. In this study, rice plants under drought and high salinity conditions showed increased nitric oxide synthase (NOS) activity and NO levels. Overexpression of rat neuronal NO synthase (nNOS) in rice increased both NOS activity and NO accumulation, resulting in improved tolerance of the transgenic plants to both drought and salt stresses. nNOS-overexpressing plants exhibited stronger water-holding capability, higher proline accumulation, less lipid peroxidation and reduced electrolyte leakage under drought and salt conditions than wild rice. Moreover, nNOS-overexpressing plants accumulated less H2O2, due to the observed up-regulation of OsCATA, OsCATB and OsPOX1. In agreement, the activities of CAT and POX were higher in transgenic rice than wild type. Additionally, the expression of six tested stress-responsive genes including OsDREB2A, OsDREB2B, OsSNAC1, OsSNAC2, OsLEA3 and OsRD29A, in nNOS-overexpressing plants was higher than that in the wild type under drought and high salinity conditions. Taken together, our results suggest that nNOS overexpression suppresses the stress-enhanced electrolyte leakage, lipid peroxidation and H2O2 accumulation, and promotes proline accumulation and the expression of stress-responsive genes under stress conditions, thereby promoting increased tolerance to drought and salt stresses.


Asunto(s)
Sequías , Expresión Génica , Óxido Nítrico Sintasa de Tipo I/genética , Oryza/genética , Tolerancia a la Sal/genética , Adaptación Biológica , Animales , Activación Enzimática , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo I/metabolismo , Oryza/metabolismo , Plantas Modificadas Genéticamente , Ratas , Especies Reactivas de Oxígeno/metabolismo , Estrés Fisiológico/genética
11.
Plant Cell Physiol ; 56(4): 727-36, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25552473

RESUMEN

Plants exhibit reduced root growth when exposed to low temperature; however, how low temperature modulates root growth remains to be understood. Our study demonstrated that low temperature reduces both meristem size and cell number, repressing the division potential of meristematic cells by reducing auxin accumulation, possibly through the repressed expression of PIN1/3/7 and auxin biosynthesis-related genes, although the experiments with exogenous auxin application also suggest the involvement of other factor(s). In addition, we verified that ARABIDOPSIS RESPONSE REGULATOR 1 (ARR1) and ARR12 are involved in low temperature-mediated inhibition of root growth by showing that the roots of arr1-3 arr12-1 seedlings were less sensitive than wild-type roots to low temperature, in terms of changes in root length and meristem cell number. Furthermore, low temperature reduced the levels of PIN1/3 transcripts and the auxin level to a lesser extent in arr1-3 arr12-1 roots than in wild-type roots, suggesting that cytokinin signaling is involved in the low-temperature-mediated reduction of auxin accumulation. Taken together, our data suggest that low temperature inhibits root growth by reducing auxin accumulation via ARR1/12.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Frío , Proteínas de Unión al ADN/metabolismo , Ácidos Indolacéticos/metabolismo , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Factores de Transcripción/metabolismo , Arabidopsis/citología , Proteínas de Arabidopsis/genética , Recuento de Células , División Celular , Proteínas de Unión al ADN/genética , Regulación de la Expresión Génica de las Plantas , Meristema/citología , Meristema/crecimiento & desarrollo , Meristema/metabolismo , Raíces de Plantas/citología , Estrés Fisiológico , Factores de Transcripción/genética
12.
Zhongguo Zhong Yao Za Zhi ; 40(16): 3229-32, 2015 Aug.
Artículo en Chino | MEDLINE | ID: mdl-26790298

RESUMEN

Chemical constituents from the acetone extract of twigs of Manglietia hookeri were isolated and purified by various column chromatographic methods over silica gel and sephadex LH-20, and preparative TLC. The structures of these compounds were identified on the basis of physicochemical properties and spectral analysis, including NMR and MS spectra. Six eudesmane sesquiterpenes were obtained and their structures were identified as trans-eudesmane-4, 11-diol(1), ß-eudesmol(2), (-) -10-epi-5ß-hydroxy-ß-eudesmol (3), epi-carrisone (4), 6-hydroxy-eudesm-4(14) -ene(5) and gynurenol(6). All the compounds were isolated from this plant for the first time. Furthermore, the 13C-NMR data of compound 3 were reported for the first time.


Asunto(s)
Medicamentos Herbarios Chinos/química , Magnolia/química , Sesquiterpenos de Eudesmano/química , Medicamentos Herbarios Chinos/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Estructura Molecular , Tallos de la Planta/química , Sesquiterpenos de Eudesmano/aislamiento & purificación , Espectrometría de Masa por Ionización de Electrospray
13.
Funct Plant Biol ; 41(4): 342-352, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32480995

RESUMEN

The basic/helix-loop-helix (bHLH) transcription factors are ubiquitous transcriptional regulators that control many different developmental and physiological processes in the eukaryotic kingdom. In this study, the function of AtbHLH112, an uncharacterised member of the bHLH family in Arabidopsis was investigated. Overexpression of AtbHLH112 suppressed lateral root (LR) development in Arabidopsis seedlings. Examination under the microscope revealed that abnormal lateral root primordia (LRP) with flat-head and more than four cell layers retained in the endodermal layer account for over 45% of the total number of LRP and LRs. This suggests that LRP emergence was prevented before LRP penetrated the cortical layer in the transgenic lines. Decreased auxin level within the LRP and parental root cells surrounding the LRP, as well as downregulated expression of cell-wall-remodelling (CWR) genes in the roots may contribute to the suppression of LR emergence in AtbHLH112-overexpressing lines. This finding was further supported by the observation that exogenous application of auxin recovered LR development and upregulated the expression of CWR genes in AtbHLH112-overexpressing lines.

14.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 11): o3251, 2012 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-23284548

RESUMEN

The title compound, C(15)H(20)O(4), is a eudesmanolide isolated from the Chinese medicinal plant Carpesium tris-te Maxim. The mol-ecule contains three rings, viz. two fused six-membered rings in chair conformations and a five-membered ring in a flattened envelope conformation. In the crystal, two hy-droxy groups are involved in the formation of intra- and inter-molecular O-H⋯O hydrogen bonds. The H atoms in these groups are split, with site-occupation factors of 0.5. The inter-molecular hydrogen bonds link mol-ecules into chains propagating in [010].

15.
Planta Med ; 78(2): 141-7, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22025343

RESUMEN

Six new lignans, 1- 6, along with six known compounds were obtained from the flower buds of Magnolia liliflora Desr. The new lignans were elucidated as (1 S*,2 R*,5 S*,6 S*)-2-(3,5-dimethoxyphenyl)-6-(3,4-methylenedioxyphenyl)-3,7-dioxabicyclo[3.3.0]octane (1), (1 R*,2 R*,5 R*,6 S*)-2-(3,5-dimethoxyphenyl)-6-(3,4-methylenedioxyphenyl)-3,7-dioxabicyclo[3.3.0]octane (2), (1 R*, 2 R*,5 R*,6 S*)-2,6-bis (3,5-dimethoxyphenyl)-3,7-dioxabicyclo[3.3.0]octane (3), (1 R*,2 S*,5 R*,6 R*)-2-(3,4-methylenedioxyphenyl)-6-(3,5-dimethoxyphenyl)-3,7-dioxabicyclo[3.3.0]octane ( 4), (7' S*,8 R*,8' R*)-3,5'-dimethoxy-3',4,9'-trihydroxy-7',9-epoxy-8,8'-lignan (5), and (7' R*,8' S*)-3,3',4,5'-tetramethoxy-7-en-7',9-epoxy-8,8'-lignan (6), by the analysis of 1D and 2D-NMR as well as HRESIMS data. The capacity of compound 1 to protect against damages to the DNA of rat lymphocyte cells induced by UV irradiation was assessed by the comet assay. It showed stronger antigenotoxicity than ascorbic acid from 6×10(-3) mmol·L(-1) to 6×10(-6) mmol·L(-1).


Asunto(s)
Daño del ADN , Flores/química , Lignanos/farmacología , Linfocitos/efectos de los fármacos , Magnolia/química , Extractos Vegetales/farmacología , Animales , Lignanos/aislamiento & purificación , Linfocitos/efectos de la radiación , Extractos Vegetales/química , Ratas
16.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 6): o1361, 2011 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-21754755

RESUMEN

The title eremophilenolide, C(15)H(22)O(3), is a natural compound isolated from Senecio laetus Edgew. The two cis-fused six-membered rings have chair confomations and the five-membered ring has a planar envelope conformation [maximum deviation = 0.010 (1) Å]. The ß-hy-droxy group participates in inter-molecular O-H⋯O hydrogen bonding, forming mol-ecular chains along the a axis.

17.
Nat Prod Res ; 24(4): 370-4, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20221943

RESUMEN

A new jacaranone derivative, 2-(1,6-dihydroxy-4-oxocyclohex-2-enyl) acetic acid (1), has been isolated from the whole plants of Senecio scandens var. incisus, together with three known compounds: 2'-(p-hydroxyl-cinnamoyl)-6'-jacaranone-D-glucopyranoside (2), 2'-caffeoyl-6'-jacaranone-D-glucopyranoside (3) and kampferol-3-rhamnoside (4). Their structures were elucidated on the basis of spectroscopic data analyses and by comparison with the related known compounds. Cytotoxic activities of 1 against three human tumour cell lines have been evaluated by the MTT method.


Asunto(s)
Antineoplásicos Fitogénicos/aislamiento & purificación , Benzoquinonas/aislamiento & purificación , Senecio/química , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Benzoquinonas/química , Benzoquinonas/farmacología , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Espectroscopía de Resonancia Magnética , Análisis Espectral/métodos
18.
Zhong Yao Cai ; 33(9): 1414-6, 2010 Sep.
Artículo en Chino | MEDLINE | ID: mdl-21243771

RESUMEN

OBJECTIVE: The study was to provided the reference for further development and utilization of Ligularia hodgsonii. METHODS: The crude polysaccharide LW was extracted from Lugularia hodgsonii with hot water, and prectated by ethanol. The crude polysaccharide has been fractionted and purified, so LW21 was got. Its homogeneity was confirmed by chromatography on Sepharose CL-4B, paper chromatography and cellulous actate electrophoresis. The scavenging effets of the polysacehardes on * OH and O2-* were determined by fluorescence method. RESULTS: Antioxidative experiment shows that LW and LW21 were effective in scavenging superoxide radical and hydroxyl radical. The scavenging capacity for superoxide radical and hydroxyl radical of LW21 had higher than that of LW. CONCLUSION: The polysaceharide from Ligularia hodgsonii had stronger antioxidant actioxdant activities, and their antioxidant activities had certain dose-relationship.


Asunto(s)
Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , Asteraceae/química , Radicales Libres/metabolismo , Polisacáridos/aislamiento & purificación , Polisacáridos/farmacología , Antioxidantes/química , Etanol , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/aislamiento & purificación , Depuradores de Radicales Libres/farmacología , Radical Hidroxilo/metabolismo , Polisacáridos/química , Espectrofotometría Ultravioleta , Agua
19.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 8): o2161, 2010 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-21588445

RESUMEN

The title compound, C(18)H(26)O(7), is an eremophilenolide which has been isolated from the plant Ligularia duciformis for the first time. The present study confirms the atomic connectivity assigned on the basis of (1)H and (13)C NMR spectroscopy. The mol-ecule contains three fused rings, two six-membered rings in chair confomations and a five-membered ring in a flattened envelope conformation. Two hy-droxy groups are involved in formation of intra- and inter-molecular O-H⋯O hydrogen bonds. The latter ones link mol-ecules into chains propagating in [010].

20.
Zhong Yao Cai ; 31(8): 1165-7, 2008 Aug.
Artículo en Chino | MEDLINE | ID: mdl-19112896

RESUMEN

OBJECTIVE: To investigate the chemical constituents of Pteris multifida. METHODS: All compounds were isolated and purified by normal column chromatography, paper thin layer chromatography and sephadex chromatography. The chemical structures were mainly elucidated by ESI mass and NMR spectra. RESULTS: Seven compounds were isolated from the methanol extracts of Pteris multifida. In addition to a glycoside of sesquiterpene pterosin C-3-O-beta-D-glucoside(1), six flavonoids were isolated from S. barbata as fouows: apigenin(2), luteolin(3), apigenin-7-O-beta-D-glucoside(4), apigenin-7-O-beta-D-glucosyl-4'-O-alpha-L-rhanrnoside(5), apigenin-4'-O-alpha-L-rhanrnoside(6) and luteolin-7-O-beta-D-glucoside(7). CONCLUSION: Compound(2), (3) and (5), (6) are isolated from Pteris multifida for the first time.


Asunto(s)
Flavonoides/aislamiento & purificación , Plantas Medicinales/química , Pteridaceae/química , Sesquiterpenos/aislamiento & purificación , Apigenina/química , Apigenina/aislamiento & purificación , Flavonoides/química , Glucósidos/química , Glucósidos/aislamiento & purificación , Luteolina/química , Luteolina/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Sesquiterpenos/química
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