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1.
Molecules ; 24(22)2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31717454

RESUMO

Endophytes have been recognized as a source for structurally novel and biologically active secondary metabolites. Among the host plants for endophytes, some medicinal plants that produce pharmaceuticals have been reported to carry endophytes, which could also produce bioactive secondary metabolites. In this study, the medicinal plant Aconitum carmichaeli was selected as a potential source for endophytes. An endophytic microorganism, Aureobasidium pullulans AJF1, harbored in the flower of Aconitum carmichaeli, was cultured on a large scale and extracted with an organic solvent. Extensive chemical investigation of the extracts resulted in isolation of three lipid type compounds (1-3), which were identified to be (3R,5R)-3,5-dihydroxydecanoic acid (1), (3R,5R)-3-(((3R,5R)-3,5-dihydroxydecanoyl)oxy)-5-hydroxydecanoic acid (2), and (3R,5R)-3-(((3R,5R)-5-(((3R,5R)-3,5-dihydroxydecanoyl)oxy)-3-hydroxydecanoyl)oxy)-5-hydroxydecanoic acid (3) by chemical methods in combination with spectral analysis. Compounds 2 and 3 had new structures. Absolute configurations of the isolated compounds (1-3) were established using modified Mosher's method together with analysis of NMR data for their acetonide derivatives. All the isolates (1-3) were evaluated for antibiotic activities against Escherichia coli, Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, and their cytotoxicities against MCF-7 cancer cells. Unfortunately, they showed low antibiotic activities and cytotoxic activities.


Assuntos
Ascomicetos/metabolismo , Ácidos Decanoicos/química , Ácidos Decanoicos/metabolismo , Hidroxiácidos/química , Hidroxiácidos/metabolismo , Aconitum/genética , Aconitum/metabolismo , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Ascomicetos/genética , Bactérias/efeitos dos fármacos , Ácidos Decanoicos/síntese química , Ácidos Decanoicos/farmacologia , Humanos , Hidroxiácidos/síntese química , Hidroxiácidos/farmacologia , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Estrutura Molecular
2.
J Pharmacol Exp Ther ; 370(3): 736-741, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31092539

RESUMO

Pasty polymers offer a platform for injectable implants for drug delivery. A library of biodegradable pasty polymers was synthesized by bulk ring-opening polymerization of lactide, glycolide, trimethylene carbonate, or caprolactone using castor oil or 12-hydroxy stearic acid as hydroxyl initiators and stannous octoate as the catalyst. Some of the polymers behaved as Newtonian liquids. Pasty polymers of poly(caprolactone) and poly(trimethylene carbonate) were stable under physiologic conditions for over 1 month in vitro, whereas polymers of poly(lactic-co-glycolic acid) degraded within 10 days. These pasty polymers offer a platform for pasty injectable biodegradable carriers for drugs and fillers. SIGNIFICANCE STATEMENT: New injectable pasty, in situ forming drug delivery systems are described and are advantageous due to their ease of administration, tunable viscosity, and biodegradability. Polyesters based on lactide, glycolide, trimethylene carbonate, and caprolactone, which are commonly used as absorbable implants and drug carriers, were conjugated onto natural hydroxyl fatty acids. These polymers have potential use as wrinkle fillers and drug carriers.


Assuntos
Plásticos Biodegradáveis , Óleo de Rícino/química , Hidroxiácidos/química , Lactonas/química , Polímeros , Portadores de Fármacos , Stents Farmacológicos , Ácidos Graxos/química , Injeções , Viscosidade
3.
Mater Sci Eng C Mater Biol Appl ; 85: 79-87, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29407160

RESUMO

Scaffolds with extracellular matrix-like fibrous morphology, suitable mechanical properties, biomineralization capability, and excellent cytocompatibility are desired for bone regeneration. In this work, fibrous and degradable poly(ester urethane)urea (PEUU) scaffolds reinforced with titanium dioxide nanoparticles (nTiO2) were fabricated to possess these properties. To increase the interfacial interaction between PEUU and nTiO2, poly(ester urethane) (PEU) was grafted onto the nTiO2. The scaffolds were fabricated by electrospinning and exhibited fiber diameter of <1µm. SEM and EDX mapping results demonstrated that the PEU modified nTiO2 was homogeneously distributed in the fibers. In contrast, severe agglomeration was found in the scaffolds with unmodified nTiO2. PEU modified nTiO2 significantly increased Young's modulus and tensile stress of the PEUU scaffolds while unmodified nTiO2 significantly decreased Young's modulus and tensile stress. The greatest reinforcement effect was observed for the scaffold with 1:1 ratio of PEUU and PEU modified nTiO2. When incubating in the simulated body fluid over an 8-week period, biomineralization was occurred on the fibers. The scaffolds with PEU modified nTiO2 showed the highest Ca and P deposition than pure PEUU scaffold and PEUU scaffold with unmodified nTiO2. To examine scaffold cytocompatibility, bone marrow-derived mesenchymal stem cells were cultured on the scaffold. The PEUU scaffold with PEU modified nTiO2 demonstrated significantly higher cell proliferation compared to pure PEUU scaffold and PEUU scaffold with unmodified nTiO2. The above results demonstrate that the developed fibrous nanocomposite scaffolds have potential for bone tissue regeneration.


Assuntos
Materiais Biomiméticos/farmacologia , Calcificação Fisiológica/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Nanocompostos/química , Poliuretanos/farmacologia , Alicerces Teciduais/química , Titânio/farmacologia , Animais , Líquidos Corporais/química , Cálcio/análise , Proliferação de Células/efeitos dos fármacos , Hidroxiácidos/síntese química , Hidroxiácidos/química , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanocompostos/ultraestrutura , Fósforo/análise , Poliuretanos/síntese química , Poliuretanos/química , Propionatos/síntese química , Propionatos/química , Ratos , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier
4.
Zhong Yao Cai ; 35(6): 869-72, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23236817

RESUMO

OBJECTIVE: To investigate the effect of artermisinic acid on the secondary metabolites production of Panax quinquefolium crown galls. METHODS: Artemisinic acid was added into the suspended cells of Panax quinquefolium crown galls and co-culture for two days. Products were isolated with chromatographic method. RESULTS: Three hydroxyl octadecenoic acids [9,12,13-trihydroxy-10-octadecenoic acid (1), 11,12,13-trihydroxy-9-octadecenoic acid (2) and 11-hydroxy-12,13-epoxy-9-octadecenoic acid (3)] were isolated from crown galls of Panax quinquefolium. CONCLUSION: Artermisinic acid as one of the new type of phytohormones that might induce the production of 13-lipoxygenases in crown galls of Panax quinquefolium.


Assuntos
Artemisininas/farmacologia , Ácidos Graxos/biossíntese , Panax/metabolismo , Plantas Medicinais/metabolismo , Células Cultivadas , Cromatografia Líquida de Alta Pressão/métodos , Meios de Cultura , Ácidos Graxos/química , Ácidos Graxos/isolamento & purificação , Hidroxiácidos/química , Hidroxiácidos/isolamento & purificação , Ácidos Oleicos/biossíntese , Ácidos Oleicos/química , Ácidos Oleicos/isolamento & purificação , Panax/efeitos dos fármacos , Panax/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , Plantas Medicinais/efeitos dos fármacos , Plantas Medicinais/crescimento & desenvolvimento , Técnicas de Cultura de Tecidos/métodos
5.
Zhong Yao Cai ; 34(4): 546-8, 2011 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-21809539

RESUMO

OBJECTIVE: To study the chemical constituents of Codonopsis pilosula. METHODS: The compounds were isolated and purified by column chromatography and their structures were elucidated through spectroscopic techniques (NMR) and physicochemical properties. RESULTS: The compounds were isolated as hesperidin(I), n-hexyl beta-sophoroside(II), atractylenolide III (III), lobetyolin(IV), lobetyolinin(V), taraxerol(VI), taraxeryl acetate(VII), alpha-spinasterol(VIII),9,10,13-trihydroxy-(E)-11-octadecenoic acid (IX),beta-sitosterol(X),beta-daucosterol(XI)and sugar(XII). CONCLUSION: Compounds 1 -2 and 9 are isolated from this plant for the first time.


Assuntos
Codonopsis/química , Hesperidina/isolamento & purificação , Hidroxiácidos/isolamento & purificação , Ácidos Oleicos/isolamento & purificação , Plantas Medicinais/química , Hesperidina/química , Hidroxiácidos/química , Lactonas/química , Lactonas/isolamento & purificação , Estrutura Molecular , Ácidos Oleicos/química , Poli-Inos/química , Poli-Inos/isolamento & purificação , Controle de Qualidade , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação
6.
Planta Med ; 77(11): 1183-8, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21294076

RESUMO

Bioassay-guided fractionation of the N-hexane and CHCl3 phases of the methanol extract of the roots of Conyza canadensis (L.) Cronquist led to the isolation of two new dihydropyranones named conyzapyranone A (1) and B (2), and the known 4 Z,8 Z-matricaria- γ-lactone (3), 4 E,8 Z-matricaria- γ-lactone (4), 9,12,13-trihydroxy-10(E)-octadecenoic acid (5), epifriedelanol (6), friedeline (7), taraxerol (8), simiarenol (9), spinasterol (10), stigmasterol, ß-sitosterol, and apigenin. The structures were determined by means of ESIMS and 1D and 2D NMR spectroscopy, including ¹H-¹H COSY, NOESY, HSQC, and HMBC experiments. The isolated compounds were evaluated for their antiproliferative activities and were demonstrated to exert considerable cell growth-inhibitory activity against human cervix adenocarcinoma (HeLa), skin carcinoma (A431), and breast adenocarcinoma (MCF-7) cells. Some of the active components, including 2, 4, and 10, proved to be substantially more potent against these cell lines than against noncancerous human foetal fibroblasts (MRC-5) and can therefore be considered selective antiproliferative natural products.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Conyza/química , Raízes de Plantas/química , Pironas/química , Apigenina/química , Linhagem Celular Tumoral , Fracionamento Químico/métodos , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Hidroxiácidos/química , Espectroscopia de Ressonância Magnética/métodos , Estrutura Molecular , Óleos Voláteis/farmacologia , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/química , Ácidos Oleicos/química , Extratos Vegetais/química , Pironas/isolamento & purificação , Sitosteroides/química , Estigmasterol/análogos & derivados , Estigmasterol/química
7.
Int Immunopharmacol ; 10(6): 655-61, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20230917

RESUMO

Pinellic acid from the tuber of Pinellia ternata was isolated as an effective oral adjuvant for nasal influenza vaccine, and identified 9S,12S,13S-trihydroxy-10E-octadecenoic acid (9S,12S,13S) by the enantioselective total synthesis [Nagai et al., Int. Immunopharmacol., 2, 1183-93 (2002); Shirahata et al., Tetrahedron, 62, 9483-96 (2006)]. However, present study showed that synthetic 9S,12S,13S that was nearly 100% pure was not effective as an oral adjuvant. HPLC analysis also showed that the adjuvant active pinellic acid fraction from tuber of P. ternata contained the 9S,12S,13S as the main component and at least two minor components. Therefore seven other chemically synthesized stereoisomers were tested in combination with the 9S,12S,13S for oral adjuvant activity. Only the 9S,12S,13S in combination with the 9S,12R,13R isomer in a weight% ratio of 90.4:9.6 (pinellic acid mixture, PAM) was a potent oral adjuvant and elicited both antiviral IgA antibody (Ab) in bronchoalveolar lavage fluids and nasal washes and antiviral IgG(1) Ab in mice sera. Oral administration of the PAM followed by nasal influenza vaccination and infection with A/PR/8/34 virus showed increases in survival rate (22%, control versus 78% test) in mice orally administered PAM as adjuvant. Histopathological examination of lung tissue of mice given oral PAM with vaccine followed by influenza virus infection showed attenuated infiltration of inflammatory cells with decreases in the alveolar spaces and increases in the alveolar septa. The result of this study refutes the our previous study and suggests that the combination of 9S,12S,13S and 9S,12R,13R isomers is necessary for effective oral adjuvant activity when used in conjunction with nasal influenza vaccine.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Ácidos Graxos Insaturados/administração & dosagem , Hidroxiácidos/administração & dosagem , Vírus da Influenza A Subtipo H1N1 , Vacinas contra Influenza/administração & dosagem , Influenza Humana/prevenção & controle , Ácidos Oleicos/administração & dosagem , Adjuvantes Imunológicos/química , Administração Intranasal , Administração Oral , Animais , Anticorpos Antivirais/sangue , Líquido da Lavagem Broncoalveolar/imunologia , Medicamentos de Ervas Chinesas/uso terapêutico , Ácidos Graxos Insaturados/química , Feminino , Humanos , Hidroxiácidos/química , Imunoglobulina A/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Vacinas contra Influenza/imunologia , Pulmão/imunologia , Pulmão/microbiologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Ácidos Oleicos/química , Pinellia/química , Estereoisomerismo
8.
Fitoterapia ; 81(5): 339-42, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19836436

RESUMO

A new ceramide and a new poly-hydroxyl octadecenoic acid were isolated from transgenic crown galls of Panax quinquefolium. Their structures were elucidated as (2S, 3S, 4R, 20E)-2-[(2'R)-2'-hydroxyl-palmitoyl-amino]-20-hexacosene-1, 3, 4-triol (1) and 12, 13, 15-trihydroxy-9-octadecenoic acid (2) respectively on the basis of spectroscopic and chemical methods.


Assuntos
Ceramidas/isolamento & purificação , Hidroxiácidos/isolamento & purificação , Ácidos Oleicos/isolamento & purificação , Panax/química , Extratos Vegetais/química , Plantas Geneticamente Modificadas/química , Agrobacterium tumefaciens/genética , Ceramidas/química , Hidroxiácidos/química , Estrutura Molecular , Ácidos Oleicos/química , Panax/genética , Panax/microbiologia , Extratos Vegetais/isolamento & purificação , Tumores de Planta/microbiologia , Plantas Geneticamente Modificadas/microbiologia
9.
J Nat Prod ; 69(9): 1366-9, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16989538

RESUMO

The new norisoprenoid 3beta-hydroxy-5alpha,6alpha-epoxy-beta-ionone-2alpha-O-beta-d-glucopyranoside (1) and the long-chain hydroxy fatty acids 9,12,13-trihydroxyoctadeca-10(E),15(Z)-dienoic acid (2) and 9,12,13-trihydroxyoctadeca-10(E)-dienoic acid (3) were isolated from Salsola tetrandra aerial parts, together with 3,4,5-trimethoxyphenyl-beta-d-glucopyranoside (4), 9-hydroxylinaloyl glucoside (5), taxiphyllin (6), trans-N-feruloyltyramine (7), and S-(-)-trans-N-feruloyloctopamine (8). Their structures were elucidated by extensive spectroscopic analysis and chemical methods. Compounds 6 and 8 displayed mild antibacterial activity against Staphylococcus aureus, whereas compound 6 showed the highest activity in the Artemia salina bioassay.


Assuntos
Antibacterianos/isolamento & purificação , Hidroxiácidos/isolamento & purificação , Ácidos Oleicos/isolamento & purificação , Plantas Medicinais/química , Salsola/química , Antibacterianos/química , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Glucosídeos , Hidroxiácidos/química , Hidroxiácidos/farmacologia , Testes de Sensibilidade Microbiana , Micrococcus luteus/efeitos dos fármacos , Estrutura Molecular , Norisoprenoides , Ressonância Magnética Nuclear Biomolecular , Ácidos Oleicos/química , Ácidos Oleicos/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus/efeitos dos fármacos , Tunísia
10.
Lipids ; 39(5): 491-505, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15506246

RESUMO

The lipids of the gram-negative bacterium Marinobacter hydrocarbonoclasticus grown in a synthetic seawater medium supplemented with various hydrocarbons as the sole carbon source were isolated, purified, and their structures determined. The hydrocarbons were normal, iso, anteiso, and mid-chain branched alkanes, phenylalkanes, cyclohexylalkanes, and a terminal olefin. According to the sequential procedure used for lipid extraction, three pools were isolated: unbound lipids extracted with organic solvents (corresponding to metabolic lipids and to the main part of membrane lipids), OH- labile lipids [mainly ester-bound in the lipopolysaccharides (LPS)], and H+ labile lipids (mainly amide-bound in the LPS). Each pool contained FA, fatty alcohols, and beta-hydroxy acids. The proportions of these lipids in the unbound lipid pools were 84-98%, 1.1-11.6%, and 0.1-3.6% (w/w), respectively. The chemical structures of the lipids were strongly correlated with those of the hydrocarbons fed; analytical data suggested a metabolism essentially through oxidation into primary alcohol, then into FA and degradation via the beta-oxidation pathway. Sub-terminal oxidation of the hydrocarbon chains, alpha-oxidation of FA or double-bond oxidation in the case of the terminal olefin, were minor, although sometimes substantial, routes of hydrocarbon degradation. Cyclohexyldodecane did not support growth, likely because of the toxicity of cyclohexylacetic acid formed in the oxidation of the alkyl side chain. In the OH- and H+ labile lipid pools, beta-hydroxy acids, the lipophilic moiety of LPS, generally dominated (28-72% and 64-98%, w/w, respectively). The most remarkable feature of these cultures on hydrocarbons was the incorporation in LPS of beta-hydroxy acids with Codd, omega-unsaturated, iso, or anteiso alkyl chains in addition to the specific beta-hydroxy acid of M. hydrocarbonoclasticus, 3-OH-n-12:0. These beta-hydroxy acids were tolerated insofar as their geometry and steric hindrance were close to those of the 3-OH-n-12:0 acid.


Assuntos
Alteromonadaceae/metabolismo , Hidrocarbonetos/química , Hidrocarbonetos/metabolismo , Lipídeos/química , Ácidos Graxos/química , Álcoois Graxos/química , Hidroxiácidos/química , Lipopolissacarídeos/química , Estrutura Molecular , Oxirredução , Água do Mar/microbiologia
11.
Lipids ; 39(1): 75-9, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15055238

RESUMO

The lipids of the gram-negative marine bacterium Marinobacter hydrocarbonoclasticus, cultivated in synthetic seawater supplemented with 1-chlorooctadecane as sole source of carbon, were isolated, purified, and their structures determined. Three pools of lipids were isolated according to the sequential procedure used: unbound lipids extracted by organic solvents, ester-bound lipids released under alkaline conditions, and amide-bound lipids released by acid hydrolysis. FA isolated from the unbound lipids included omega-chlorinated (21%, w/w, of this fraction; C16 predominant) and nonchlorinated compounds (22%, w/w; C18 predominant). These acids were accompanied by a high proportion of omega-chloro-C18 alcohols (43%, w/w) and a lower amount of omega-chloro-beta-hydroxy-C18, -C16, and -C14 acids (5%, w/w). These data, together with the isolation from the culture medium of gamma-butyrolactone, suggested a metabolism of 1-chlorooctadecane through oxidation into omega-chloro acid and then the classic beta-oxidation pathway. The analysis of the ester-bound and amide-bound lipids revealed that significant amounts of omega-chloro-beta-hydroxy C10-C12 acids were incorporated into the lipopolysaccharides of the bacterium. Incorporation of these omega-chloro-beta-hydroxy acids into the lipopolysaccharides represents a novel route for chloroalkane assimilation in hydrocarbonoclastic gram-negative bacteria. The formation of chlorinated hydroxy acids, like the omega-chloro FA in the cellular lipids, could account for an incomplete mineralization of chloroparaffins in the environment.


Assuntos
Ácidos Graxos/química , Bactérias Gram-Negativas/química , Hidrocarbonetos Clorados/química , Hidroxiácidos/química , Ácidos Graxos/metabolismo , Bactérias Gram-Negativas/metabolismo , Hidrocarbonetos Clorados/metabolismo , Hidroxiácidos/metabolismo , Metabolismo dos Lipídeos , Lipídeos/química
12.
Z Naturforsch C J Biosci ; 58(5-6): 355-60, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12872929

RESUMO

The composition of hexane and ether extracts from buds of two poplar species (Populus balsamifera and P. nigra) was investigated by GC-MS method. In hexane extracts, 54 "neutral" compounds were recorded. The greatest amounts of them are sesquiterpenes and n-alkanes. Among 56 components of ether extracts, many aliphatic acids and hydroxyacids were detected. However, the main fraction consists of phenolcarboxylic acids, substituted cinnamic acids, and their esters. It was established that chemotaxonomic differences between Populus balsamifera and P. nigra are observed in the case of both hexane and ether bud extracts.


Assuntos
Flores/química , Extratos Vegetais/química , Populus/química , Sesquiterpenos/química , Alcanos/química , Alcanos/isolamento & purificação , Ácidos Carboxílicos/química , Ácidos Carboxílicos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Hidroxiácidos/química , Hidroxiácidos/isolamento & purificação , Populus/classificação , Sesquiterpenos/isolamento & purificação , Especificidade da Espécie
13.
Arch Pharm Res ; 26(3): 207-9, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12723933

RESUMO

A new unsaturated hydroxy acid was isolated from the stem bark extract of Albizzia julibrissin through repeated silica gel and Sephadex LH-20 column chromatography. The chemical structure of the new acid was determined as (E)-4-hydroxy-dodec-2-enedioic acid on the basis of several spectral data including 2D-NMR. The stereochemical feature of the double bond was determined to be E on the basis of the coupling pattern of related proton signals in the 1H-NMR and COSY experiments.


Assuntos
Albizzia , Hidroxiácidos/química , Hidroxiácidos/isolamento & purificação , Casca de Planta , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Caules de Planta
14.
Int J Biol Macromol ; 27(5): 355-61, 2000 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-10998494

RESUMO

Medium-chain-length poly(hydroxyalkanoate) (mcl-PHA) polymers derived from linseed oil (PHA-L) have a relatively small molar mass and contain a high concentration of unsaturated side-chains. As such, these polymers are amorphous and take on the consistency of a viscous liquid at room temperature. In order to increase the application potential of this material, the side-chain olefinic groups of PHA-L were converted to epoxy derivatives (PHA-LE) using m-chloroperoxybenzoic acid (m-CPBA). Epoxidation resulted in a 37% conversion of olefinic to epoxy groups. The epoxy groups enhanced the PHA-LE film susceptibility to crosslinking upon exposure to air. PHA-LE films began to crosslink and stiffen in less than 25 days, whereas PHA-L films began to crosslink between days 50 and 75. The PHA-LE films showed an increase in tensile strength (TS, from 4.8 to 20.7 MPa) and Young's modulus (YM, from 12.9 to 510.6 MPa) between 25 and 100 days. In contrast, PHA-L had a TS of 25.0 MPa and YM of 767.8 MPa after 100 days. Epoxidation helped induce crosslink formation; however, aging for 100 days ultimately resulted in crosslinked films from both PHA-L and PHA-LE with higher strength and durability than the original materials.


Assuntos
Hidroxiácidos/química , Óleo de Semente do Linho/química , Fenômenos Biomecânicos , Elasticidade , Compostos de Epóxi/química , Linho/química , Viscosidade
15.
Eur J Biochem ; 259(1-2): 331-8, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9914511

RESUMO

From the edible mushroom, the basidiomycetes Agaricus bisporus and Agaricus campestris, a novel carbohydrate-homologous series of four glyco-inositol-phospho-sphingolipids, designated basidiolipids, was isolated and the constituents purified. The chemical structures of the basidiolipids were elucidated to be: Manpbeta1-2inositol1-phospho-ceramide, Galpalpha-6[Fucpalpha-2]Galpbeta-6Manpbeta-2i nositol1-phospho-ceramide, Galpalpha-6Galpalpha-6[Fucpalpha-2]Galpbeta- 6Manpbeta-2inositol1-phospho-ceramide and Galpalpha-6Galpalpha-6Galpalpha-6[Fucpalpha-2] Galpbeta-6Manpbeta-2ino sitol1-phospho-ceramide. All four glycolipids contained a ceramide which was composed of phytosphingosine and predominantly alpha-hydroxy-behenic and alpha-hydroxy-lignoceric acid.


Assuntos
Agaricus/química , Ceramidas/química , Fosfatos de Inositol/isolamento & purificação , Fosfolipídeos/química , Esfingosina/análogos & derivados , Adjuvantes Imunológicos/química , Sequência de Carboidratos , Ácidos Graxos/química , Hidroxiácidos/química , Dados de Sequência Molecular , Ressonância Magnética Nuclear Biomolecular , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Esfingosina/isolamento & purificação
16.
Mol Divers ; 1(3): 177-82, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-9237208

RESUMO

A small-molecule synthetic combinatorial library was designed and synthesized that features potential pharmacophores attached to a variety of small cyclic scaffolds. The synthesis of the library involved randomization of three types of building blocks: 20 amino acids, 10 aromatic hydroxy acids and 21 alcohols, totaling a library complexity of 4200 compounds. Mitsunobu polymer-supported etherification was used in the last randomization. The library compounds were attached to beads via an ester-bond linkage enabling both on-bead as well as in-solution screening. When the library was tested against a model target, streptavidin, specific binders were found. The structures of the most active compounds were determined from the fragmentation pattern in MS/MS experiments.


Assuntos
Evolução Molecular Direcionada/métodos , Álcoois/síntese química , Álcoois/química , Aminoácidos/síntese química , Aminoácidos/química , Proteínas de Bactérias , Sítios de Ligação , Química Orgânica/métodos , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Hidroxiácidos/síntese química , Hidroxiácidos/química , Espectrometria de Massas , Estrutura Molecular , Estreptavidina
17.
Z Naturforsch C J Biosci ; 50(1-2): 98-104, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7702715

RESUMO

A test system is described, which allows the search for compounds interfering with human sex hormone-binding globulin (SHBG) even in complex plant extracts. The method has been evaluated and applied to Urtica dioica root extracts. The lignan secoisolariciresinol (5) as well as a mixture of isomeric (11 E)-9,10,13-trihydroxy-11-octadecenoic and (10 E)-9,12,13-trihydroxy-10-octadecenoic acids (3 and 4, resp.) were demonstrated to reduce binding activity of human SHBG. Methylation of the mixture of 3 and 4 increased its activity about 10-fold.


Assuntos
Hidroxiácidos/farmacologia , Ácidos Oleicos/farmacologia , Extratos Vegetais/farmacologia , Plantas Medicinais , Globulina de Ligação a Hormônio Sexual/antagonistas & inibidores , Di-Hidrotestosterona/metabolismo , Feminino , Humanos , Hidroxiácidos/química , Hidroxiácidos/isolamento & purificação , Cinética , Metilação , Estrutura Molecular , Ácidos Oleicos/química , Ácidos Oleicos/isolamento & purificação , Raízes de Plantas , Gravidez , Terceiro Trimestre da Gravidez , Ligação Proteica , Albumina Sérica/isolamento & purificação , Albumina Sérica/metabolismo , Globulina de Ligação a Hormônio Sexual/isolamento & purificação
18.
Can J Microbiol ; 41 Suppl 1: 14-21, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7606658

RESUMO

Poly(hydroxyalkanoates) (PHAs) were isolated from Pseudomonas aeruginosa 44T1 cultivated on euphorbia oil and castor oil. With the aid of 2-D proton NMR spectra and proton-detected multiple bond coherence NMR spectra the structures of the PHAs were determined. In addition to the usual PHA constituents (C6-C14 3-hydroxy fatty acids), PHAs formed from euphorbia oil contained delta 8,9-epoxy-3-hydroxy-5c-tetradecenoate, and probably delta 6,7-epoxy-3-hydroxydodecanoate and delta 4,5-epoxy-3-hydroxydecanoate. These novel constituents account for approximately 15% of the total amount of monomers and are clearly generated via beta-oxidation of vernolic acid (delta 12,13-epoxy-9c-octadecenoic acid), the main component of euphorbia oil. In PHAs formed from castor oil, 7% of the monomers found were derived from ricinoleic acid (12-hydroxy-9c-octadecenoic acid). The presence of 3,8-dihydroxy-5c-tetradecenoate was clearly demonstrated. Furthermore, NMR analysis strongly suggested the presence of 3,6-dihydroxydodecanoate, 6-hydroxy-3c-dodecenoate, and 4-hydroxydecanoate.


Assuntos
Ácidos Graxos/metabolismo , Hidroxiácidos/metabolismo , Poliésteres/metabolismo , Pseudomonas aeruginosa/metabolismo , Óleo de Rícino/metabolismo , Compostos de Epóxi/metabolismo , Hidroxiácidos/química , Espectroscopia de Ressonância Magnética , Ácidos Oleicos/metabolismo , Oxirredução , Óleos de Plantas/metabolismo , Poliésteres/química , Ácidos Ricinoleicos/metabolismo
19.
Eur J Biochem ; 199(1): 153-5, 1991 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-2065670

RESUMO

We found that (R,S)-2-hydroxy-2-trifluoromethyl-trans-n-octadec-4-enoic acid (HTFOA) is a powerful activator of 5-lipoxygenase from potato tubers. The degree of activation of the enzyme is proportional to the HTFOA concentration and is a maximum at about 0.1 mM independently of initial substrate concentration (25 microM or 0.1 mM). At greater concentrations of HTFOA, enzyme inhibition takes place. Enzyme activation is inversely proportional to the substrate (linoleic acid) concentration. The results may be explained by assuming that a regulatory center exists in the enzyme molecule, which shows affinity to both substances: activator and linoleic acid.


Assuntos
Araquidonato 5-Lipoxigenase/metabolismo , Ácidos Graxos Monoinsaturados/farmacologia , Hidroxiácidos/farmacologia , Solanum tuberosum/enzimologia , Ativação Enzimática , Ácidos Graxos Monoinsaturados/química , Hidroxiácidos/química , Cinética , Ácido Linoleico , Ácidos Linoleicos/química , Oxirredução
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