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1.
Colloids Surf B Biointerfaces ; 216: 112579, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35598510

RESUMO

A mesoporous crosslinked chitosan-activated clinoptilolite biocomposite (CS-GA/ACP) was prepared with chitosan (CS) as the substrate and glutaraldehyde (GA) as the crosslinking agent. Structural analysis of the CS-GA/ACP composite beads was performed using FTIR, SEM, and BET techniques. The adsorption properties of the CS-GA/ACP for Congo red (CR) and methylene blue (MB) removal were examined using a batch method. The effects of CS loading, CS-GA/ACP dosages (0.005-0.25 g), pH values (3-11), initial concentrations (30-300 mg/L), contact time (5-120 min), ionic strength, and temperatures (25-65 â„ƒ) on the adsorption of CR and MB on the CS-GA/ACP composite beads were investigated. The pseudo-second-order kinetics could better describe the adsorption process than the pseudo-first-order kinetics, and the Langmuir isotherms model agreed well with the experimental data. The maximum adsorption capacities of the CS-GA/ACP for CR and MB were 180.59 mg/g and 143.67 mg/g at 25 â„ƒ, respectively. The proposed mechanism studies showed that the possible interaction between the adsorbent and dye molecules were Yoshida H-bonding, dipole-dipole H-bonding, electrostatic interaction and n-π interaction. The CS-GA/ACP can be recycled to remove dyes without significant loss of efficacy, and the adsorption of dyes on the CS-GA/ACP is spontaneous endothermic adsorption. Overall, the CS-GA/ACP showed an excellent performance for dyes removal in aqueous solution and could be a practical candidate for industrial applications.


Assuntos
Quitosana , Poluentes Químicos da Água , Adsorção , Cátions , Quitosana/química , Corantes/química , Vermelho Congo/química , Glutaral/química , Concentração de Íons de Hidrogênio , Cinética , Azul de Metileno/química , Poluentes Químicos da Água/química , Zeolitas
2.
Z Naturforsch C J Biosci ; 65(1-2): 39-42, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20355319

RESUMO

A new ent-halimane-type diterpene, named 5(10),14-ent-halimadien-3beta,13S-diol (1), was isolated from the bark of Amoora ouangliensis and its chemical structure determined on the basis of spectroscopic analysis. Additionally, ten other diterpenoids were obtained from A. ouangliensis and A. stellato-squamosa. The bioactive experiments of all compounds against AGZY 83-a (human lung cancer cells) and SMMC-7721 (human liver cancer cells) cells were documented.


Assuntos
Antineoplásicos/uso terapêutico , Diterpenos/uso terapêutico , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/patologia , Meliaceae/química , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Linhagem Celular Tumoral , Cisplatino/farmacologia , Diterpenos/química , Diterpenos/isolamento & purificação , Humanos , Espectroscopia de Ressonância Magnética , Modelos Moleculares
4.
Phys Med Biol ; 52(19): 5735-48, 2007 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-17881797

RESUMO

This paper presents a systematic procedure to evaluate the induced current densities and electric fields due to walk-through metal detector (WTMD) exposure. This procedure is then used to assess the exposure of nine pregnant women models exposed to one WTMD model. First, we measured the magnetic field generated by the WTMD, then we extracted the equivalent current source to represent the WTMD emissions and finally we calculated the induced current densities and electric fields using the impedance method. The WTMD emissions and the induced fields in the pregnant women and fetus models are then compared to the ICNIRP Guidelines and the IEEE C95.6 exposure safety standard. The results prove the consistency between maximum permissible exposure (MPE) levels and basic restrictions for the ICNIRP Guidelines and IEEE C95.6. We also found that this particular WTMD complies with the ICNIRP basic restrictions for month 1-5 models, but leads to both fetus and pregnant women overexposure for month 6-9 models. The IEEE C95.6 restrictions (MPEs and basic restrictions) are not exceeded. The fetus overexposure of this particular WTMD calls for carefully conducted safety evaluations of security systems before they are deployed.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Exposição Ambiental/análise , Metais/análise , Complicações na Gravidez/etiologia , Gravidez/efeitos da radiação , Medidas de Segurança , Simulação por Computador , Feminino , Humanos , Modelos Biológicos , Complicações na Gravidez/prevenção & controle , Doses de Radiação , Lesões por Radiação/prevenção & controle , Proteção Radiológica/métodos , Radiometria/métodos , Medição de Risco/métodos , Fatores de Risco
5.
Yao Xue Xue Bao ; 42(3): 292-6, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17520829

RESUMO

A new compound and twelve known compounds were isolated from the ethyl acetate extract of the roots of Homonoia riparia Lour, which are used in folk medicine for treatment of hepatitis, bellyache and scald, by the method of silica gel column chromatography repeatedly with a gradient of PE-EtOAc, PE-Me2CO, CHCl3-Me2CO, CHCl3-MeOH. Their structures were identified as a new compound 1-oxo-aleuritolic acid (1), and twelve known compounds aleuritolic acid (2), 3-acetoxy-aleuritolic acid (3), taraxerone (4), taraxerol (5), methyl 3-acetoxy-12-oleanen-28-oate (6), 3-acetoxy-12-oleanen-28-ol (7), ursolic acid (8), lupenol (9), 3beta-acetoxy-lupenol (10), cleomiscosin A (11), chrysophanol (12), and gallic acid (13), which were obtained from this plant for the first time, by the spectroscopic techniques of NMR, HMBC, IR and MS, separately. Among the cytotoxicities evaluation of compounds 1 -3 towards AGZY 83-a (human lung cancer cells) and SMMC-7721 (human liver cancer cells) tumor cells was assayed by MTT methods with cis-dichlorodiamminoplatinum (DDP) used as positive control. Compound 2 exerted weak activity against AGZY 83-a with the IC50 value of 33.055 microg x mL(-1), while 1 and 3 showed no activity to these two cell lines.


Assuntos
Euphorbiaceae/química , Raízes de Plantas/química , Plantas Medicinais/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cumarínicos , Dioxanos/química , Dioxanos/isolamento & purificação , Dioxanos/farmacologia , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/química , Ácido Oleanólico/isolamento & purificação , Ácido Oleanólico/farmacologia , Ácidos Palmíticos/química , Ácidos Palmíticos/isolamento & purificação , Ácidos Palmíticos/farmacologia , Triterpenos/química , Triterpenos/isolamento & purificação , Triterpenos/farmacologia
6.
Magn Reson Chem ; 45(2): 189-92, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17146802

RESUMO

Seven rings A,B-seco limonoids 1-7 were isolated from the EtOH extract of the seed of Aphanamixis polystachya. Their structures were identified as rohituka-7 (1), dregeana-1 (2), rohituka-15 (3), Tr-B (4), rohituka-3 (5), rohituka-5 (6), and rohituka-14 (7) by MS and NMR spectroscopy. The complete assignment of proton and carbon signals was achieved by 1D and 2D NMR experiments including DEPT, HSQC, 1H--1H COSY, HMBC, and NOESY.


Assuntos
Limoninas/química , Espectroscopia de Ressonância Magnética , Meliaceae/química , Isótopos de Carbono , Hidrogênio , Limoninas/isolamento & purificação , Estrutura Molecular , Sementes/química
7.
Chem Biodivers ; 3(2): 224-30, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17193261

RESUMO

Four new polyphenolic glycosides (1-4) were isolated from the BuOH extract of the bark of Walsura yunnanenis C. Y. Wu. These compounds comprise two lignans, i.e., the 9-O-alpha-L-arabinopyranosides 1 and 2 of (-)-isolariciresinol and of (+)-5-methoxyisolariciresinol, respectively, and the two phenolic glycosides 3,4,5-trimethoxyphenyl 2-O-(alpha-L-fucopyranosyl)-beta-D-glucopyranoside (3) and 3,5-dihydroxyphenyl 6-O-(4-hydroxy-3,5-dimethoxybenzoyl)-beta-D-glucopyranoside (walsuraside; 4). In addition, three known compounds, 3,4,5-trimethoxyphenyl beta-D-glucopyranoside, asperglaucide, and butyl alpha-D-fructofuranoside were identified. Their structures were elucidated spectroscopically and by chemical transformation (hydrolysis). The new compounds 1, 2, and 4 displayed significant antioxidant activities, with IC(50) values in the range of ca. 42 to 49 microg/ml.


Assuntos
Antioxidantes/isolamento & purificação , Glicosídeos/isolamento & purificação , Meliaceae/química , Fenóis/isolamento & purificação , Antioxidantes/química , Glicosídeos/química , Fenóis/química , Casca de Planta , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação
8.
Z Naturforsch C J Biosci ; 61(3-4): 193-5, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16729576

RESUMO

A new tetranortriterpene 3alpha-acetoxy-24,25,26,27-tetranortirucalla-7-ene-23(21)-lactone (3), and eleven other compounds were isolated from the twigs of Amoora dasyclada. The structure of compound 3 was identified on the basis of spectroscopic data, and the bioactive experiments of 1 and 3-5 against AGZY 83-a (human lung cancer cells) and SMMC-7721 (human liver cancer cells) are documented. Among them, compound 5 exhibited a strong activity against SMMC-7721.


Assuntos
Antineoplásicos/química , Extratos Vegetais/química , Triterpenos/química , Animais , Antineoplásicos/isolamento & purificação , Antineoplásicos/toxicidade , Divisão Celular/efeitos dos fármacos , China , Modelos Moleculares , Caules de Planta/química , Triterpenos/isolamento & purificação , Triterpenos/toxicidade
9.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 24(9): 827-30, 2004 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-15495831

RESUMO

OBJECTIVE: To study the effect of THW-4, an extract from Trypterygium hypoglaucum on proliferation and apoptosis of vascular smooth muscle cells (VSMC). METHODS: VSMC derived from rabbit aorta were cultured in vitro and different concentrations of THW-4 were added in experimental groups. Cell proliferation was evaluated by MTT and apoptosis by transmission electron microscopy (TEM), TUNEL assay and Annexin V-FITC/PI double labelled assay. RESULTS: The inhibitory effects of THW-4 on proliferation of VSMC displayed dose-time dependently, with the IC50 value of 15.6 microg/L at 48 hrs. Incubated with THW-4 (10-100 microg/L) for 56 hrs, VSMC mainly appeared early stage apoptosis and the percentage of apoptosis was found to raise along with the increase of the THW-4 concentration. Typical images of apoptosis could be observed under TEM and TUNEL assay showed increase of DNA segments with karyorrhexis and pyknosis after THW-4 treatment for 72 hrs. Analysis of cell cycle indicated the THW-4 mainly lead to the blockage of VSMC in G2/M stage. CONCLUSION: THW-4 could inhibit the proliferation and induce the apoptosis of VSMC in vitro, suggesting that THW-4 is a potential agent for prevention of restenosis following angioplasty.


Assuntos
Apoptose/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Músculo Liso Vascular/citologia , Tripterygium/química , Animais , Aorta/citologia , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Reestenose Coronária/prevenção & controle , Masculino , Coelhos
10.
Pharmazie ; 59(6): 488-90, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15248467

RESUMO

Nine compounds were isolated from the EtOH extraction of the twig of Carapa guianensis Aubl. On the basis of spectroscopic methods, their structures were elucidated as 1,3-di-benzene carbon amine-2-octadecylic acid-glyceride (1), hexacosanoic acid-2,3-dihydroxy-glyceride (2), ursolic acid (3), naringenin (4), scopoletin (5), 3,4-dihydroxymethylbenzoate (6), 2,6-dihydroxymethylbenzoate (7), tetratriacontanoic acid (8), triacontanoic acid (9) respectively. Among them 1 was new, 2 was firstly isolated from nature, and 3-9 were obtained from this plant for the first time.


Assuntos
Meliaceae/química , Fenômenos Químicos , Físico-Química , Espectroscopia de Ressonância Magnética , Caules de Planta/química , Espectrofotometria Ultravioleta
11.
J Agric Food Chem ; 51(24): 6949-52, 2003 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-14611152

RESUMO

A novel A,B-seco-tetranortriterpenoid lactam, named munroniamide (1), along with three known ceramides (2-4), was isolated from the methanolic extract of the whole bodies of Munronia henryi. The structure of 1 was established using spectroscopic methods. Compound 2 exhibited significant antifeeding activity, and 1 exhibited moderate activity, whereas 3 and 4 showed negative activity against Pieris brassicae L.


Assuntos
Inseticidas/química , Limoninas/química , Meliaceae/química , Triterpenos/química , Animais , Ceramidas/química , Ceramidas/isolamento & purificação , Ingestão de Alimentos/efeitos dos fármacos , Insetos/fisiologia , Inseticidas/isolamento & purificação , Inseticidas/farmacologia , Limoninas/isolamento & purificação , Limoninas/farmacologia , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Extratos Vegetais/química , Triterpenos/isolamento & purificação , Triterpenos/farmacologia
12.
J Asian Nat Prod Res ; 5(3): 215-21, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12931855

RESUMO

Six compounds were isolated from the MeOH extract of the whole bodies of Munronia henryi. Their structures were elucidated as sitosterol-3-O-12',13'-epoxy-9'-oxo-(10'E)-octadecenoate (1), alpha-D-glucopyranosyl-6'-O-hexadecanoate (2), 4alpha,7alpha-aromodendranediol (3), 2beta,3beta,4beta-trihydroxypregnan-16-one (4), 4-O-alpha-D-psicofuranos-alpha-D-glucopyranose (5), and glyceryl-1-tetracosanoicate (6) on the basis of spectroscopic methods. Among them 1 was a new sterol carrying an octadecenoyl; 2 and 6 were isolated for the first time from a natural source.


Assuntos
Meliaceae/química , Esteróis/isolamento & purificação , Metanol/química , Extratos Vegetais/química , Folhas de Planta/química , Solventes/química , Esteróis/química
13.
J Asian Nat Prod Res ; 4(2): 135-40, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12067159

RESUMO

Three new monoterpene glycosides, 4-O-ethylpaeoniflorin (1), 6'-O-benzoyl-4''-hydroxy-3"-methoxy-paeoniflorin (2), 6'-O-benzoylalbiflorin (3), and a new monoterpenoid, 9-hydroxy-paeonilactone-A (4) were isolated from the root cortex of Paeonia delavayi. Their structures were elucidated on the basis of spectral methods.


Assuntos
Glicosídeos/isolamento & purificação , Monoterpenos/isolamento & purificação , Paeonia/química , Plantas Medicinais/química , Terpenos/isolamento & purificação , Glicosídeos/química , Espectrometria de Massas , Monoterpenos/química , Terpenos/química
14.
Yao Xue Xue Bao ; 37(1): 33-6, 2002 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-12579896

RESUMO

AIM: The anti-gastric ulcer constituents from the roots of Crepis napifera (Franch) Babc (Compositae) were studied. METHODS: Solvent partition, Si gel and Rp-18 column chromatography, crystallization and spectral methods were used to extract, isolate and identify two compounds. The activity of compound 1 was tested on the rat stomach by determining the effect on aspirin-induced gastric lesions and on histamine-stimulated gastric acid secretion. RESULTS: Two sesquiterpene lactone glycosides, taraxinic acid-1'-O-beta-D-glucopyranoside (1) and 11,13-dihydro-taraxinic acid-1'-O-beta-D-glucopyranoside (2) were obtained. Compound 1 at the dose of 80 mg.kg-1 p.o. inhibited significantly the development of aspirin-induced gastric lesions in the rat and at an i.v. dose of 70 mg.kg-1 did not affect histamine-stimulated gastric acid secretion in the lumen-perfused rat stomach. CONCLUSION: Compound 1 is the active component of the plant which protects gastric mucosa and exhibits anti-gastric ulcer action.


Assuntos
Antiulcerosos/uso terapêutico , Crepis/química , Plantas Medicinais/química , Sesquiterpenos/uso terapêutico , Úlcera Gástrica/tratamento farmacológico , Animais , Antiulcerosos/química , Antiulcerosos/isolamento & purificação , Antiulcerosos/farmacologia , Aspirina , Modelos Animais de Doenças , Feminino , Ácido Gástrico/metabolismo , Mucosa Gástrica/metabolismo , Masculino , Conformação Molecular , Estrutura Molecular , Raízes de Plantas/química , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Úlcera Gástrica/induzido quimicamente
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