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1.
Fitoterapia ; 177: 106106, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38945492

RESUMO

The Cichorium plants are particularly notable due to their remarkable therapeutic and medicinal properties, besides being used as food and conventional medication. Although Cichorium plants have been studied for their phytoconstituents and biological activities, there is limited knowledge about the constituents of the roots of C. bottae. A phytochemical study of the 90% MeOH extract of C. bottae roots resulted in the isolation of twelve compounds belonging to guaianolide sesquiterpene lactones, sesquiterpene lactone glucosides, and phenolic derivatives, of which two compounds designated as 9α-hydroxycrepediaside B (1) and cichobotinal (2) were previously undescribed. The isolated compounds were assessed for their anti-inflammatory potential through the inhibition of inducible nitric oxide synthase (iNOS) and resultant decrease in nitric oxide generation in LPS-induced macrophages. Among the isolates, compounds 2 and 11 (8-deoxylactucin) inhibited iNOS activity with IC50 values of 21.0 ± 4 and 6.8 ± 0.1 µM, respectively. The methanolic extract of C. bottae inhibited iNOS with an IC50 of 10.5 ± 0.5 µg/mL.


Assuntos
Anti-Inflamatórios , Macrófagos , Óxido Nítrico Sintase Tipo II , Óxido Nítrico , Compostos Fitoquímicos , Extratos Vegetais , Raízes de Plantas , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/isolamento & purificação , Raízes de Plantas/química , Células RAW 264.7 , Camundongos , Animais , Estrutura Molecular , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico/metabolismo , Macrófagos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Lactonas/farmacologia , Lactonas/isolamento & purificação , Sesquiterpenos/farmacologia , Sesquiterpenos/isolamento & purificação , Fenóis/farmacologia , Fenóis/isolamento & purificação , Glucosídeos/farmacologia , Glucosídeos/isolamento & purificação , Sesquiterpenos de Guaiano/farmacologia , Sesquiterpenos de Guaiano/isolamento & purificação
2.
J Ethnopharmacol ; 289: 115062, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35114339

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Ferula hermonis is a small shrub renowned for its aphrodisiac abilities. Middle East herbalists have utilized Ferula hermonis seed and root as an aphrodisiac folk medicine to treat women's frigidity and male erectile and sexual dysfunction. AIM OF THE STUDY: Assessment of follicle-stimulating hormone-like (FSH), luteinizing hormone-like (LH), and estrogenic activities of the methanolic extract (ME) of the roots of Ferula hermonis on female reproductive function. MATERIALS AND METHODS: The methanolic extract was prepared from the root of F. hermonis and studied at dose level 6 mg/kg in immature female rats for FSH-like, LH-like, and estrogenic activities. These activities were determined by analyzing gross anatomical features, relative organ weight, and serum level of FSH, LH, progesterone and estrogen hormones, and histopathological characteristics. Quantification of the main phytoestrogenic component ferutinin carried out by HPLC. In addition, molecular docking for the binding affinity of ferutinin inside active sites of both estrogen receptor alpha (ERα) and FSH receptor (FSHR) was performed to predict the potential role of ferutinin in regulating the female reproductive process. RESULTS: Ferula hermonis (ME) showed potent FSH-like, LH-like activities and moderate estrogenic effect at the dose of 6 mg/kg. The content of ferutinin in F. hermonis was estimated to be 92 ± 1.33 mg/g of the methanolic extract. Molecular docking of ferutinin with ERα and FSHR displayed strong interaction with target proteins. CONCLUSIONS: Based on results, it can be concluded that Ferula hermonis can be considered as a suitable female fertility improving agent.


Assuntos
Benzoatos/farmacologia , Cicloeptanos/farmacologia , Fármacos para a Fertilidade/farmacologia , Ferula/química , Extratos Vegetais/farmacologia , Sesquiterpenos/farmacologia , Animais , Benzoatos/isolamento & purificação , Compostos Bicíclicos com Pontes/isolamento & purificação , Compostos Bicíclicos com Pontes/farmacologia , Cromatografia Líquida de Alta Pressão , Cicloeptanos/isolamento & purificação , Feminino , Fertilidade , Fármacos para a Fertilidade/isolamento & purificação , Hormônio Foliculoestimulante/metabolismo , Hormônio Luteinizante/metabolismo , Simulação de Acoplamento Molecular , Ratos , Sesquiterpenos/isolamento & purificação
3.
J Environ Sci Health B ; 53(2): 135-140, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29173073

RESUMO

As an alternative to synthetic pesticides, natural materials such as plant extracts and microbes have been considered to control plant diseases. In this study, methanol extracts of 120 plants were explored for in vivo antifungal activity against Rhizoctonia solani, Botrytis cinerea, Phytophthora infestans, Puccinia triticina, and Blumeria graminis f. sp. hordei. Of the 120 plant extracts, eight plant extracts exhibited a disease control efficacy of more than 90% against at least one of five plant diseases. In particular, a methanol extract of Curcuma zedoaria rhizomes exhibited strong activity against wheat leaf rust caused by P. triticina. When the C. zedoaria methanol extracts were partitioned with various solvents, the layers of n-hexane, methylene chloride, and ethyl acetate showed disease control values of 100, 80, and 43%, respectively, against wheat leaf rust. From the C. zedoaria rhizome extracts, an antifungal substance was isolated and identified as a sesquiterpene ketolactone based on the mass and nuclear magnetic resonance spectral data. The active compound controlled the development of rice sheath blight, wheat leaf rust, and tomato late blight. Considering the in vivo antifungal activities of the sesquiterpene ketolactone and the C. zedoaria extracts, these results suggest that C. zedoaria can be used as a potent fungicide in organic agriculture.


Assuntos
Curcuma/química , Fungicidas Industriais/farmacologia , Lactonas/farmacologia , Doenças das Plantas/prevenção & controle , Extratos Vegetais/farmacologia , Sesquiterpenos/farmacologia , Acetatos/química , Basidiomycota/efeitos dos fármacos , Basidiomycota/patogenicidade , Fungicidas Industriais/química , Hexanos , Lactonas/química , Lactonas/isolamento & purificação , Solanum lycopersicum/microbiologia , Metanol/química , Estrutura Molecular , Agricultura Orgânica/métodos , Oryza/microbiologia , Extratos Vegetais/química , Rhizoctonia/efeitos dos fármacos , Rhizoctonia/patogenicidade , Rizoma/química , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Solventes/química , Triticum/microbiologia
4.
PLoS Negl Trop Dis ; 11(9): e0005929, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28945741

RESUMO

Four sesquiterpene lactones, mikanolide, deoxymikanolide, dihydromikanolide and scandenolide, were isolated by a bioassay-guided fractionation of Mikania variifolia and Mikania micrantha dichloromethane extracts. Mikanolide and deoxymikanolide were the major compounds in both extracts (2.2% and 0.4% for Mikania variifolia and 21.0% and 6.4% for Mikania micrantha respectively, calculated on extract dry weight). Mikanolide, deoxymikanolide and dihydromikanolide were active against Trypanosoma cruzi epimastigotes (50% inhibitory concentrations of 0.7, 0.08 and 2.5 µg/mL, for each compound respectively). These sesquiterpene lactones were also active against the bloodstream trypomastigotes (50% inhibitory concentrations for each compound were 2.1, 1.5 and 0.3 µg/mL, respectively) and against amastigotes (50% inhibitory concentrations for each compound were 4.5, 6.3 and 8.5 µg/mL, respectively). By contrast, scandenolide was not active on Trypanosoma cruzi. Besides, mikanolide and deoxymikanolide were also active on Leishmania braziliensis promastigotes (50% inhibitory concentrations of 5.1 and 11.5 µg/mL, respectively). The four sesquiterpene lactones were tested for their cytotoxicity on THP 1 cells. Deoxymikanolide presented the highest selectivity index for trypomastigotes (SI = 54) and amastigotes (SI = 12.5). In an in vivo model of Trypanosoma cruzi infection, deoxymikanolide was able to decrease the parasitemia and the weight loss associated to the acute phase of the parasite infection. More importantly, while 100% of control mice died by day 22 after receiving a lethal T. cruzi infection, 70% of deoxymikanolide-treated mice survived. We also observed that this compound increased TNF-α and IL-12 production by macrophages, which could contribute to control T. cruzi infection.


Assuntos
Lactonas/farmacologia , Leishmania braziliensis/efeitos dos fármacos , Mikania/química , Extratos Vegetais/farmacologia , Sesquiterpenos/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Doença de Chagas/tratamento farmacológico , Doença de Chagas/parasitologia , Descoberta de Drogas , Interleucina-12/biossíntese , Interleucina-12/imunologia , Lactonas/administração & dosagem , Lactonas/química , Lactonas/isolamento & purificação , Lactonas/uso terapêutico , Estágios do Ciclo de Vida/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Extratos Vegetais/química , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos de Germacrano/administração & dosagem , Sesquiterpenos de Germacrano/isolamento & purificação , Sesquiterpenos de Germacrano/farmacologia , Sesquiterpenos de Germacrano/uso terapêutico , Trypanosoma cruzi/isolamento & purificação , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/imunologia
5.
Int J Mol Sci ; 16(4): 8997-9016, 2015 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-25913379

RESUMO

Biorefinery applications are receiving growing interest due to climatic and waste disposal issues and lack of petroleum resources. Jerusalem artichoke (Helianthus tuberosus L.) is suitable for biorefinery applications due to high biomass production and limited cultivation requirements. This paper focuses on the potential of Jerusalem artichoke as a biorefinery crop and the most viable products in such a case. The carbohydrates in the tubers were found to have potential for production of platform chemicals, e.g., succinic acid. However, economic analysis showed that production of platform chemicals as a single product was too expensive to be competitive with petrochemically produced sugars. Therefore, production of several products from the same crop is a must. Additional products are protein based ones from tubers and leaves and biogas from residues, although both are of low value and amount. High bioactive activity was found in the young leaves of the crop, and the sesquiterpene lactones are of specific interest, as other compounds from this group have shown inhibitory effects on several human diseases. Thus, future focus should be on understanding the usefulness of small molecules, to develop methods for their extraction and purification and to further develop sustainable and viable methods for the production of platform chemicals.


Assuntos
Helianthus/química , Extratos Vegetais/química , Produtos Agrícolas/química , Humanos , Lactonas/química , Lactonas/economia , Lactonas/isolamento & purificação , Extratos Vegetais/economia , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Proteínas de Plantas/química , Proteínas de Plantas/economia , Proteínas de Plantas/isolamento & purificação , Raízes de Plantas/química , Sesquiterpenos/química , Sesquiterpenos/economia , Sesquiterpenos/isolamento & purificação
6.
Environ Toxicol Pharmacol ; 37(1): 110-7, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24317194

RESUMO

5ß-Hydroxypalisadin B, a halogenated secondary metabolite isolated from red seaweed Laurencia snackeyi was evaluated for its anti-inflammatory activity in lipopolysaccharide (LPS)-induced zebrafish embryo. Preliminary studies suggested the effective concentrations of the compound as 0.25, 0.5, 1 µg/mL for further in vivo experiments. 5ß-Hydroxypalisadin B, exhibited profound protective effect in the zebrafish embryo as confirmed by survival rate, heart beat rate, and yolk sac edema size. The compound acts as an effective agent against reactive oxygen species (ROS) formation induced by LPS and tail cut. Moreover, 5ß-hydroxypalisadin B effectively inhibited the LPS-induced nitric oxide (NO) production in zebrafish embryo. All the tested protective effects of 5ß-hydroxypalisadin B were comparable to the well-known anti-inflammatory agent dexamethasone. According to the results obtained, 5ß-hydroxypalisadin B isolated from red seaweed L. snackeyi could be considered as an effective anti-inflammatory agent which might be further developed as a functional ingredient.


Assuntos
Anti-Inflamatórios/farmacologia , Sesquiterpenos/farmacologia , Animais , Anti-Inflamatórios/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Laurencia/química , Lipopolissacarídeos , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sesquiterpenos/isolamento & purificação , Peixe-Zebra
7.
An Acad Bras Cienc ; 86(4): 1563-72, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25590700

RESUMO

Chemical transformations of eremantholide C (1), a sesquiterpene lactone that was isolated from Lychnophora trichocarpha Spreng. led to five new derivatives: 1',2'- epoxyeremantholide C (2), 5-n-propylamine-4,5-dihydro-1',2'-epoxyeremantholide C (3), 5-n-propylammonium-4,5-dihydro-1',2'-epoxyeremantholide C chloride (4), 5-n-propylammonium-4,5-dihydroeremantolide C chloride (5) and 16-O-ethyleremantholide C (6). The structures of all these derivatives were assigned on the basis of IR, MS, 1H and 13C NMR data by 1D and 2D techniques. Eremantholide C and the derivatives 2, 4 and 5 were evaluated against trypomastigotes Y and CL strains of Trypanosoma cruzi. Eremantholide C completely inhibited the growth of both the parasites strains while all derivatives were partially active against the CL strain and inactive against the Y strain.


Assuntos
Asteraceae/química , Extratos Vegetais/farmacologia , Sesquiterpenos/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Parasitária , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação
8.
Biodegradation ; 24(5): 685-98, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23266763

RESUMO

Experiments were conducted in a laboratory-scale biofilter to assess the ability of a fixed-film biological process to treat an air stream containing ß-caryophyllene, a sesquiterpene emitted by a variety of conifer trees as well as industrial wood processing operations. Treatment performance was evaluated under a variety of pollutant loading conditions and nutrient supply rates over an operational period lasting more than 240 days. At empty bed contact times (EBCTs) as low as 10 s and daily average pollutant loading rate as high as 24.2 g C/(m(3) h) (grams pollutant measured as carbon per cubic meter packed bed volume per hour), removal efficiencies in excess of 95 % were observed when sufficient nutrients were supplied. Results demonstrate that, as with biofilters treating other compounds, biofilters treating ß-caryophyllene can experience local nutrient limitations that result in diminished performance. The biofilter successfully recovered high removal efficiency within a few days after resumption of pollutant loading following a 14-day interval of no contaminant loading. Construction of a 16S rRNA gene library via pyrosequencing revealed the presence of a high proportion of bacteria clustering within the genera Gordonia (39.7 % of the library) and Rhodanobacter (37.6 %). Other phylotypes detected at lower relative abundances included Pandoraea (6.2 %), unclassified Acetobacteraceae (5.5 %), Dyella (3.3 %), unclassified Xanthomonadaceae (2.6 %), Mycobacterium (1.8 %), and Nocardia (0.6 %). Collectively, results demonstrate that ß-caryophyllene can be effectively removed from contaminated gas streams using biofilters.


Assuntos
Poluentes Atmosféricos/isolamento & purificação , Filtração/métodos , Consórcios Microbianos , Sesquiterpenos/isolamento & purificação , Bactérias/genética , Bactérias/metabolismo , Sequência de Bases , Biodegradação Ambiental , Filtração/instrumentação , Sesquiterpenos Policíclicos , RNA Ribossômico 16S/genética , Compostos Orgânicos Voláteis/análise
9.
J Ethnopharmacol ; 144(2): 362-70, 2012 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-23000115

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Leaves of Smallanthus sonchifolius (Poepp. & Endl.) H. Robinson (yacon) have been used since pre-Columbian times in the Andean region to prepare medicinal herbal tea with beneficial health properties. However, there are still disagreements about the safe use. This work was carried out to evaluate the toxicity profile of both, 10% decoction of yacon leaves and their major active lactone, enhydrin. MATERIALS AND METHODS: In vitro cytotoxicity assays were performed with Hep-G2, COS1, CHO-K1 and Vero cell lines using a test of metabolic competence based upon assessment of mitochondrial performance. In vivo toxicity study was performed in adult Wistar rats. In the acute oral toxicity each group of rats was orally given a single dose of 10% decoction or enhydrin. General condition, behavior and mortality were recorded for up to 14 days post treatment. In subchronic toxicity studies, both products were given orally for 90 days to rats. Body weight and food intakes were observed weekly. Hematological, clinical chemistry parameters and organ weight were determined in all animals at the end of the experimental period. RESULTS: Cell viability decreased in a concentration dependent fashion when cells were incubated with 2-200 µg of 10% decoction and 0.015-7.5 µg of enhydrin. In acute study in rats, there were no deaths or signs of toxicity observed after oral administration of single doses of 10% decoction or enhydrin at any dose level up to the highest dose tested (14.0 g/kg and 0.32 g/kg, respectively). In subchronic studies in rats, both products administered orally for 90 days at daily doses of 0.07, 0.14 and 0.28 g 10% decoction/kg and 0.4, 0.8 and 8.0 mg enhydrin/kg, did not caused haematological, biochemical and histological alterations. CONCLUSIONS: The results presented in this paper lead us to the conclusion that the use of 10% decoction and enhydrin is safe in rat at doses in which it is demonstrated the hypoglycaemic effect.


Assuntos
Asteraceae , Hipoglicemiantes/toxicidade , Extratos Vegetais/toxicidade , Sesquiterpenos/toxicidade , Animais , Células CHO , Células COS , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Cricetinae , Cricetulus , Feminino , Células Hep G2 , Humanos , Hipoglicemiantes/isolamento & purificação , Lactonas/isolamento & purificação , Lactonas/toxicidade , Masculino , Folhas de Planta , Ratos Wistar , Sesquiterpenos/isolamento & purificação , Testes de Toxicidade Aguda , Testes de Toxicidade Subcrônica , Células Vero
10.
Phytochemistry ; 84: 94-101, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22981002

RESUMO

α-Bisabolol is a commercially important aroma chemical currently obtained from the Candeia tree (Vanillosmopsis erythropappa). Continuous unsustainable harvesting of the Candeia tree has prompted the urgent need to identify alternative crops as a source of this commercially important sesquiterpene alcohol. A chemotaxonomic assessment of two Salvia species indigenous to South Africa is presented and recommended as a potential source of α-bisabolol. The essential oil obtained by hydrodistillation of the aerial parts was analysed by gas chromatography coupled to mass spectrometry (GC-MS) and mid-infrared spectroscopy (MIRS). Orthogonal projections to latent structures-discriminant analysis (OPLS-DA) were used for multivariate classification of the oils based on GC-MS and MIRS data. Partial least squares (PLS) calibration models were developed on the MIRS data for the quantification of α-bisabolol using GC-MS as the reference method. A clear distinction between Salvia stenophylla and Salvia runcinata oils was observed using OPLS-DA on both GC-MS and MIRS data. The MIR calibration model showed high coefficient of determination (R² = 0.999) and low error of prediction (RMSEP=0.540%) for α-bisabolol content.


Assuntos
Salvia/química , Sesquiterpenos/química , Cromatografia Gasosa-Espectrometria de Massas , Conformação Molecular , Sesquiterpenos Monocíclicos , Sesquiterpenos/isolamento & purificação , Especificidade da Espécie , Espectrofotometria Infravermelho
11.
J Ethnopharmacol ; 137(1): 875-9, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21771652

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The study of traditional remedies used by the Chayahuita, an ethnic group from the Peruvian Amazonia, has prompted us to investigate in detail the ethanolic extract of Pseudelephantopus spicatus (Juss. ex Aubl.) C.F. Baker, which has demonstrated strong biological activity towards Leishmania amazonensis. Our goal was to discover the active compound of this plant-based remedy. MATERIALS AND METHODS: A bioguided fractionation of the crude extract was undertaken based on the biological activity recorded against Leishmania amazonensis axenic amastigotes in in vitro bioassays. RESULTS: Three strongly to moderately active compounds were isolated: two hirsutinolides (the 8,13-diacetyl-piptocarphol and the 8-acetyl-13-O-ethyl-piptocarphol) and ursolic acid. IC(50) against Leishmania amazonensis axenic amastigotes are respectively 0.2, 0.37 and 0.99 µM (while IC(50) of amphotericin B is 0.41 µM). These compounds have never been isolated from this plant species, and germacranolides have never been identified as potential antileishmanial agents. CONCLUSIONS: The compounds isolated from Pseudelephantopus spicatus account for the antileishmanial activity of the plant, thus giving support to its use by the Chayahuita in Peru.


Assuntos
Asteraceae , Lactonas/farmacologia , Leishmania/efeitos dos fármacos , Extratos Vegetais/farmacologia , Sesquiterpenos/farmacologia , Tripanossomicidas/farmacologia , Anfotericina B/farmacologia , Asteraceae/química , Fracionamento Químico , Relação Dose-Resposta a Droga , Humanos , Indígenas Sul-Americanos , Concentração Inibidora 50 , Lactonas/química , Lactonas/isolamento & purificação , Leishmania/crescimento & desenvolvimento , Medicina Tradicional , Peru , Componentes Aéreos da Planta , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Triterpenos/farmacologia , Tripanossomicidas/química , Tripanossomicidas/isolamento & purificação , Ácido Ursólico
12.
J Pharm Biomed Anal ; 52(2): 190-4, 2010 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-20133099

RESUMO

A new photoisomer of the promising "anti-Alzheimer" drug candidate (+/-) huperzine A is described. The new substance was formed via a photoisomerization reaction and was found to be 1-amino-13-ethylidene-11-methyl-6-aza-tetracyclo-[7.3.1.0(2.7).0(4.7)]-trideca-2,10-diene-5-one using NMR analysis. The kinetics of its formation was studied and proven to be of first-order. The described photoisomer showed a significant loss in activity, being more than 100 times less active than (-) huperzine A itself. The new substance was named photohuperzine A, referring to its photopyridone substructure.


Assuntos
Inibidores da Colinesterase/química , Inibidores da Colinesterase/metabolismo , Processos Fotoquímicos/efeitos da radiação , Sesquiterpenos/química , Alcaloides , Bioensaio , Calibragem , Cromatografia Líquida , Cinética , Espectrometria de Massas , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Padrões de Referência , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/metabolismo , Espectrofotometria Ultravioleta , Estereoisomerismo , Relação Estrutura-Atividade
13.
J Nat Prod ; 69(11): 1653-64, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17125242

RESUMO

This paper describes results of a multiobjective comparative assessment of several established and emerging technologies for extraction of a natural antimalarial substance, artemisinin. Extractions by hexane, supercritical carbon dioxide, hydrofluorocarbon HFC-134a, ionic liquids, and ethanol were considered. Hexane extraction is an established technology and appears to be the most cost-effective. However, it is characterized by lower rates and efficiency of extraction than all other considered techniques and is also worse in terms of safety and environmental impact. Similarly, EtOH extraction was found to be worse than hexane in all assessment parameters. The new technologies (scCO2, HFC, and ILs) are based on nonflammable solvents and are characterized by faster extraction cycles and more complete extraction of the useful substances and enable continuous extraction processes with reduced solvent inventory. Ionic liquid and HFC-134a technologies show considerable promise and should be able to compete with hexane extraction in terms of cost-effectiveness following due process optimization. New technologies are also considerably safer (no risk of explosions, low toxicity) and greener (having a lower environmental impact in use, potential for biodegradability after use). The methodology of comparative assessment of established and emerging technologies is discussed.


Assuntos
Antimaláricos/isolamento & purificação , Artemisia annua/química , Artemisininas , Indústria Farmacêutica/métodos , Plantas Medicinais/química , Sesquiterpenos , Artemisininas/química , Artemisininas/isolamento & purificação , Artemisininas/farmacologia , Indústria Farmacêutica/instrumentação , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia
14.
J Ethnopharmacol ; 104(1-2): 54-67, 2006 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-16203116

RESUMO

The Huperziaceae is comprised of two genera, Huperzia and Phlegmariurus. Because of the content of Lycopodium alkaloids like huperzine A, which are used to treat a number of human ailments, plants of the Huperziaceae are experiencing a rapid decline in China, mostly due to over-harvesting. Because of this trend, we engaged from 1995 to 2001 in an investigation of the natural resources of the Huperziaceae in China. The main objectives of this study were: to catalog Huperziaceae plant resources including the occurrence, general distribution, and abundance of the various Huperziaceae species in China; and to determine traditional use and pharmaceutical values of each species. Twenty-nine species, 2 varieties, and 2 forma of Huperzia and 19 species of Phlegmariurus were identified through field investigation, collection, visits with local traditional doctors, and review of specimens in herbaria and of the literature. Ethnobotanical studies of these plants revealed that 33 of these species are used by the local communities for medicinal purposes. One species, Huperzia serrata, is one of the most popular. As a result, it is observing the greatest decline, mandating a change in collection practice and general attitude towards these plants. Introduction of conservation plans and training of the local communities regarding appropriate collection practices of these plants and their marketing in China are required to reverse the trend of decline among these species. In addition, development of cultivation or other propagation practices, such as in vitro propagation, would have the added benefits of socio-economic uplift of the local communities and sustainability of this important source of huperzine A.


Assuntos
Conservação dos Recursos Naturais , Coleta de Dados , Huperzia/classificação , Sesquiterpenos/classificação , Alcaloides , China/etnologia , Conservação dos Recursos Naturais/métodos , Humanos , Estruturas Vegetais/classificação , Plantas Medicinais/classificação , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação
15.
Bioorg Med Chem ; 13(19): 5600-12, 2005 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-16039133

RESUMO

Electrospray ionization mass spectrometry-guided isolation of extracts from Didiscus aceratus led to the discovery of several new derivatives of the bioactive bisabolene-type sponge metabolite (S)-(+)-curcuphenol (1). The compounds obtained by this method included a mixture of known (2) and new (3) dihydroxylated analogs as well as a novel family of dimeric derivatives, dicurcuphenols A-E (4-8), and dicurcuphenol ether F (9). Dimers 4-9 were also subsequently obtained through a hemisynthetic method in which 1 was incubated with the enzyme laccase. Atropisomeric dimers 5 and 6 were subjected to vibrational circular dichroism analysis thereby establishing their absolute biaryl axial chirality as P and M, respectively. In contrast to 1, metabolites 2-9 exhibited weak or no cytotoxic or lipoxygenase inhibitory effects.


Assuntos
Lacase/química , Poríferos/química , Sesquiterpenos , Animais , Catálise , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Dimerização , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Inibidores de Lipoxigenase , Espectroscopia de Ressonância Magnética/métodos , Modelos Moleculares , Conformação Molecular , Sesquiterpenos/síntese química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Espectrometria de Massas por Ionização por Electrospray/métodos , Estereoisomerismo , Relação Estrutura-Atividade
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