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2.
Eur J Med Chem ; 82: 255-62, 2014 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-24910974

RESUMO

A series of 1,2,3-triazole coronopilin congeners have been designed and synthesized by employing click chemistry approach starting from parthenin and evaluated for their cytotoxicity against a panel of six human cancer cell lines (PC-3, THP-1, HCT-15, HeLa, A-549 and MCF-7). While many compounds exhibited significant anticancer activity, compound 3a, was found to be the most promising analogue in this series with IC50 values of 3.1 µM on PC-3 cell line. Flow-cytometric studies showed that 1,2,3-triazole derivative-3a induce dose dependent apoptosis in the sub G1 phase. This lead molecule-3a was further studied for NF-κB (p65) transcription factor inhibitory activity using Elisa and western blotting analysis which confirmed concentration dependent inhibitory activity against NF-κB, p65 with 80% inhibition in 24 h at 100 µM.


Assuntos
Antineoplásicos/farmacologia , Azulenos/farmacologia , Desenho de Fármacos , Sesquiterpenos/farmacologia , Triazóis/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Azulenos/síntese química , Azulenos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Células MCF-7 , Estrutura Molecular , Sesquiterpenos/síntese química , Sesquiterpenos/química , Relação Estrutura-Atividade , Triazóis/síntese química , Triazóis/química
3.
Lett Appl Microbiol ; 56(4): 275-82, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23347051

RESUMO

In this study, methodologies were developed for cost-effective, rapid and user-friendly culture-independent detection of Salmonella in milk by real-time PCR. The SYBR Green-based real-time PCR assay was standardized with primers targeting the Salmonella enterotoxin gene (stn) that have been earlier used for its detection by conventional PCR. Inclusivity tests generated the specific amplifications with a Tm corresponding to 81 ± 0·5°C. The specificity of the reaction was evaluated with a panel of 36 non-Salmonella strains. Standard curves generated, with different number of cells of this organism in milk, depicted the detection of five cells with a CT value of 37·17 (SD 0·43). To make the assays user-friendly and suitable for field applications, protocols were also established for the immobilization of the SYBR Green reaction mixes in the reaction tubes. The immobilized master mixes were stable at 25°C for 4 months and at 8°C for over 6 months. Total DNA was prepared from 150 samples of full-fat dairy milk and subjected to real-time PCR detection wherein 31 samples tested positive for Salmonella. The time of analysis was <5 h.


Assuntos
Leite/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Salmonella/isolamento & purificação , Animais , Benzotiazóis , Primers do DNA , Diaminas , Enterotoxinas/genética , Compostos Orgânicos , Quinolinas , Reprodutibilidade dos Testes , Salmonella/genética , Sensibilidade e Especificidade
4.
Braz. j. microbiol ; 43(4): 1476-1489, Oct.-Dec. 2012. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-665835

RESUMO

We have established methodology for the isolation and characterization of a novel endophytic fungus from the inner bark of medicinal plant Nothapodytes foetida, which produced camptothecin in Sabouraud broth (SB) under shake flask conditions. Camptothecin and its related compounds are at present obtained by extraction from intact plants, but fungal endopytes may be an alternative source of production. In present study we have observed the effect of different nutrient combinations and precursors (tryptophan, tryptamine, geraniol, citral, mevalonic acid and leucine) on the accumulation of camptothecin by endophytic fungus Entrophospora infrequens. The precursors were fed either alone or in combinations (tryptophan and geraniol, tryptophan and citral, tryptophan and mevalonic acid, tryptophan and leucine). The highest camptothecin content was observed in the range of 503 ± 25µg/100g dry cell mass in Sabouraud medium. Camptothecin content in the medium was increased by 2.5 folds by the presence of tryptophan and leucine whereas the production with trytophan was also significantly different from other treatments. Furthermore, the effect of fungal camptothecin on the morphology of human cancer cell lines was also studied. The treated cells showed reduction in size, condensation of nucleus and the protoplasmic extensions were reduced. All these characteristics are found in apoptotic cells.


Assuntos
Camptotecina/análise , Camptotecina/isolamento & purificação , Camptotheca , Camptotheca/genética , Fungos/genética , Técnicas In Vitro , Plantas/efeitos adversos , Métodos , Preparações de Plantas , Estruturas Vegetais
5.
World J Microbiol Biotechnol ; 28(1): 193-203, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22806795

RESUMO

Thermophilic Bacillus circulans IIIB153 isolated from hot springs of North West Himalayas, India, produced an extracellular lipase, which exhibited significant biofilm disruption property on the static biofilm disruption model with a single species of Actinomyces viscosous. The gene encoding the lipase was cloned and overexpressed in Escherichia coli. Recombinant Bacillus circulans lipase (BCL), a monomer with molecular mass of 43 kDa also exhibited significant biofilm disruption activity. The enzyme was optimally active at 60°C, pH 8.5 and retained >70% of its original activity after 1 h incubation at 60°C. 3D structure of BCL developed by homology modeling showed a typical α/ß hydrolase fold, a characteristic feature of lipolytic enzymes. Comparison of thermostable BCL with mesostable lipase from Chromobacterium viscosum at the sequence and structure level showed distinct variations in the structural features, with the presence of a high content of proline residues, aromatic amino acids and salt bridges. These features along with the presence of zinc-binding site observed in BCL structure could have a potential role in thermal stability of the enzyme.


Assuntos
Bacillus/enzimologia , Bacillus/genética , Lipase/química , Lipase/genética , Actinomyces viscosus/fisiologia , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sequência de Bases , Biofilmes/crescimento & desenvolvimento , Chromobacterium/enzimologia , Chromobacterium/genética , DNA Bacteriano/genética , Estabilidade Enzimática , Genes Bacterianos , Lipase/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Peso Molecular , Filogenia , Conformação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Temperatura
6.
Eur J Med Chem ; 51: 35-41, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22424614

RESUMO

A series of novel magnolol derivatives were synthesised and evaluated for in vitro antimicrobial and antiproliferative activities. We found that most of the compounds were effective inhibitors of Staphylococcus aureus, MRSA and VRE with MIC in the range of 1-64 µg/mL and MBC in the range of 1-128 µg/mL. Few derivatives also exhibited promising antifungal activity. Some magnolol analogues exhibited promising antiproliferative activity than parent magnolol when tested against three human cancer cell lines.


Assuntos
Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Antineoplásicos/síntese química , Compostos de Bifenilo/síntese química , Compostos de Bifenilo/farmacologia , Técnicas de Química Sintética , Desenho de Fármacos , Lignanas/síntese química , Lignanas/farmacologia , Anti-Infecciosos/química , Antifúngicos/síntese química , Antifúngicos/química , Antifúngicos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Bactérias/efeitos dos fármacos , Produtos Biológicos/química , Compostos de Bifenilo/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Humanos , Lignanas/química
7.
Braz J Microbiol ; 43(4): 1476-90, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24031979

RESUMO

We have established methodology for the isolation and characterization of a novel endophytic fungus from the inner bark of medicinal plant Nothapodytes foetida, which produced camptothecin in Sabouraud broth (SB) under shake flask conditions. Camptothecin and its related compounds are at present obtained by extraction from intact plants, but fungal endopytes may be an alternative source of production. In present study we have observed the effect of different nutrient combinations and precursors (tryptophan, tryptamine, geraniol, citral, mevalonic acid and leucine) on the accumulation of camptothecin by endophytic fungus Entrophospora infrequens. The precursors were fed either alone or in combinations (tryptophan and geraniol, tryptophan and citral, tryptophan and mevalonic acid, tryptophan and leucine). The highest camptothecin content was observed in the range of 503 ± 25µg/100g dry cell mass in Sabouraud medium. Camptothecin content in the medium was increased by 2.5 folds by the presence of tryptophan and leucine whereas the production with trytophan was also significantly different from other treatments. Furthermore, the effect of fungal camptothecin on the morphology of human cancer cell lines was also studied. The treated cells showed reduction in size, condensation of nucleus and the protoplasmic extensions were reduced. All these characteristics are found in apoptotic cells.

8.
Int Immunopharmacol ; 11(11): 1855-63, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21884823

RESUMO

Bacterial lipoproteins and their synthetic analogs are strong immune modulators of the early host responses. In view of the strong adjuvanticity of bacterial lipopeptide mimics bearing lysine residues, a focused library of lipidated dipeptides and tripeptides has been synthesized with a view to understand the pattern of activity vis a vis the site and extent of lipidation. Compounds 4, 5 and 14 stimulate OVA specific IgG titer, neutralization of antibodies (IgG1 and IgG2a), T lymphocyte sub-sets (CD4/CD8) and its production of soluble mediators for Th1 (IFN-γ)/Th2 (IL-4) cytokines and costimulatory molecules (CD80/CD86) which are ideal traits of immune adjuvants. The results support lipidated lysine dipeptides as potent enhancers of humoral and cell mediated immune responses and thus might become promising immune-adjuvants for self adjuvanted vaccines.


Assuntos
Adjuvantes Imunológicos , Carbamatos/imunologia , Lipopeptídeos/imunologia , Lisina/imunologia , Células Th1/efeitos dos fármacos , Células Th2/efeitos dos fármacos , Adjuvantes Imunológicos/síntese química , Adjuvantes Imunológicos/química , Adjuvantes Imunológicos/farmacologia , Animais , Anticorpos Neutralizantes/sangue , Antígenos CD/sangue , Carbamatos/síntese química , Carbamatos/química , Proliferação de Células/efeitos dos fármacos , Citocinas/sangue , Citocinas/imunologia , Relação Dose-Resposta Imunológica , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Imunoglobulina G/sangue , Imunofenotipagem , Lipopeptídeos/síntese química , Lipopeptídeos/química , Lisina/síntese química , Lisina/química , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Molecular , Ovalbumina/imunologia , Técnicas de Síntese em Fase Sólida , Baço/citologia , Baço/efeitos dos fármacos , Baço/imunologia , Células Th1/imunologia , Células Th2/imunologia , Vacinação/métodos
9.
Int Immunopharmacol ; 11(8): 968-75, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21371582

RESUMO

In this study, the biopolymeric fraction BOS 2000 from Boswellia serrata was evaluated for its potential ability as adjuvants on the immune responses to ovalbumin (OVA) in mice. Balb/c mice were immunized subcutaneously with OVA 100 µg alone or with OVA 100 µg dissolved in saline containing alum (200 µg) or BOS 2000 (10, 20, 40 and 80 µg) on Days 1 and 15. Two weeks later, OVA specific antibodies in serum; concanavalin A (Con A), OVA stimulated splenocyte proliferation, CD4/CD8/CD80/CD86 analysis in spleen cells and its estimation of cytokines (IL-2 and IFN gamma) from cell culture supernatant were measured. OVA specific IgG, IgG1 and IgG2a antibody levels in serum were significantly enhanced by BOS 2000 (80 µg) compared with OVA control group. Moreover, the adjuvant effect of BOS 2000 (80 µg) on the OVA-specific IgG, IgG1, and IgG2a antibody responses to OVA in mice were more significant than those of alum. BOS 2000 significantly enhanced the Con A and OVA induced splenocyte proliferation in the OVA immunized mice especially at a dose of 80 µg (p<0.001). However, no significant differences were observed among the OVA group and OVA/alum group. At a dose of 80 µg (p<0.001), there was a significant increase in the CD4/CD8 and CD80/CD86 analysis in spleen cells and cytokine (IL-2 and IFN-gamma) profile in the spleen cell culture supernatant was observed. In conclusion, BOS 2000 seems to be a promising balanced Th1 and Th2 directing immunological adjuvants which can enhance the immunogenicity of vaccine.


Assuntos
Adjuvantes Imunológicos/farmacologia , Boswellia/imunologia , Imunoglobulina G/imunologia , Ovalbumina/farmacologia , Extratos Vegetais/farmacologia , Adjuvantes Imunológicos/química , Animais , Formação de Anticorpos/efeitos dos fármacos , Especificidade de Anticorpos/efeitos dos fármacos , Antígenos CD/imunologia , Antígenos CD/metabolismo , Boswellia/química , Concanavalina A/metabolismo , Citocinas/imunologia , Citocinas/metabolismo , Imunidade Celular/efeitos dos fármacos , Imunidade Celular/imunologia , Imunização/métodos , Imunoglobulina G/sangue , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/imunologia , Extratos Vegetais/imunologia , Preparações de Plantas/química , Preparações de Plantas/imunologia , Baço/efeitos dos fármacos , Baço/imunologia , Baço/metabolismo , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th2/efeitos dos fármacos , Células Th2/imunologia
10.
J Nat Med ; 65(3-4): 578-82, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21347670

RESUMO

Picrorhiza kurrooa Royle ex Benth (Scrophulariaceae), commonly known as Kutki, is a major ingredient of many ayurvedic preparations prescribed in the treatment of various diseases. Picrosides I and II are the active agents responsible for the medicinal effects of Kutki, and the variation in content of these compounds in plants at different altitudes is a major question to be addressed. The picroside I and II content in various plant parts of P. kurrooa collected from different altitudes, viz. Sonemarg (2,740 m a.s.l.), Tangmarg (2,690 m a.s.l.), and Pulwama (1,630 m a.s.l.) in the north-western Kashmir Himalayas was analyzed by HPLC. A considerable degree of variation in picroside content was observed. Picroside I and II was highest in populations collected from Sonemarg followed by Tangmarg, suggesting that picroside accumulation is directly correlated with altitudinal change. More picroside I was found in the rhizome and roots of the Pulwama population as compared to Tangmarg samples, whereas the quantity of Picroside II was reduced in plants from Pulwama compared to the Tangmarg population, suggesting that cultivation of P. kurroa at lower altitude reduces the picroside content. The quantities of picrosides also varied spatially, being highest in rhizome followed by roots, inflorescence and leaves in the populations from all three locations. The study concludes that picroside I and II accumulation depends on altitude, which could help in the selection and collection of superior genotypes with uniform effects for utilization by the pharmaceutical industry.


Assuntos
Altitude , Cinamatos/análise , Glucosídeos Iridoides/análise , Picrorhiza/química , Extratos Vegetais/análise , Cromatografia Líquida de Alta Pressão
11.
Phytother Res ; 25(3): 324-8, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20669187

RESUMO

Butea monosperma (Lam.) (family: Fabaceae) popularly known as 'Palas' or 'fire of forest' has been used traditionally as a hepatoprotective agent. This study evaluated the hepatoprotective and antitumorigenic properties of the aqueous extract and butanol fractions of B. monosperma flowers in animal models. Dried flowers of B. monosperma were extracted with water and fractionated further using n-butanol. The hepatoprotective activity of the aqueous extract was initially confirmed in a carbon tetrachloride-induced liver damage model of rats. Oral administration of the aqueous extract produced a strong hepatoprotective effect similar to silymarin and normalized the serum levels of ALT, AST, bilirubin and triglyceride in rats. However, it did not affect the levels of glutathione and malondialdehyde which are oxidative stress markers in liver. Intraperitoneal administration of the aqueous extract in the X15-myc oncomice not only maintained liver architecture and nuclear morphometry but also down-regulated the serum VEGF levels. Immunohistochemical staining of liver sections with anti-Ribosomal protein S27a antibody showed post-treatment abolition of this proliferation marker from the tumor tissue. The butanol fractions, however, did not show antitumorigenic activity. Thus, the aqueous extract of B. monosperma flowers is not only hepatoprotective but also antitumorigenic by preserving the nuclear morphometry of the liver.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Butea/química , Núcleo Celular/efeitos dos fármacos , Neoplasias Hepáticas/patologia , Extratos Vegetais/farmacologia , Animais , Tetracloreto de Carbono , Proliferação de Células , Flores/química , Neoplasias Hepáticas/tratamento farmacológico , Camundongos , Camundongos Transgênicos , Estresse Oxidativo/efeitos dos fármacos , Ratos , Fator A de Crescimento do Endotélio Vascular/sangue
12.
Vaccine ; 28(52): 8327-37, 2010 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-20688035

RESUMO

The acylated analogs of picroside-II were synthesized and tested for immune-adjuvant activity in the presence of weak antigen ovalbumin found to stimulate anti-OVA IgG titer, neutralizing antibody (IgG1 and IgG2a) titer as well as the production of soluble mediators of a Th1 response (IL-2 and IFN-γ) and Th2 response (IL-4) and proliferation of T lymphocytes sub-sets (CD4/CD8). Furthermore, these modified analogs of picroside-II were able to elicit a substantial increase in anti-OVA IgG when compared with OVA alone. These results support the use of acylated analogs particularly PK-II-3 and PK-II-4 as potent enhancer of antigen-specific Th1 and Th2 immune responses and thus are promising immune-adjuvant candidate for vaccines.


Assuntos
Cinamatos/administração & dosagem , Cinamatos/química , Glucosídeos Iridoides/administração & dosagem , Glucosídeos Iridoides/química , Ovalbumina/imunologia , Células Th1/imunologia , Células Th2/imunologia , Acilação , Animais , Anticorpos Neutralizantes/sangue , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Proliferação de Células , Imunoglobulina G/sangue , Interferon gama/metabolismo , Interleucina-2/metabolismo , Interleucina-4/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Vacinação/métodos
13.
Nat Prod Res ; 23(14): 1304-11, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19735044

RESUMO

Withaferin A (WA) is an important withanolide holding promise in cancer treatment and as a relatively safe radiosensitive/chemotherapeutic agent, which is present in traces in all parts of Withania somnifera except the leaves, where as it is reported to be present in only two non-Indian chemotypes (South African chemotype/Israel chemotype 1). The present studies have marked its presence in all Indian populations (wild/cultivated), as well as two identified Indian chemotypes (AGB002 and AGB025). The quantitative dynamics of WA production in Indian populations and interchemotypic hybrids developed at our institute have been studied, and the results were compared with five previously reported chemotypes from Israel, South Africa and India. An analysis on inheritance characteristics based on presence/absence of WA in hybrid plants and their respective parents is given for future studies on the chemogenetics of this complex species in greater detail. Further, the production potential of WA in vitro propagated plants of elite varieties developed at our institute is discussed, in view of maintaining chemotypic fidelity and stability from a production point of view. Also, evidence-based clues suggesting the leaves as the site of the synthesis of WA is provided.


Assuntos
Ergosterol/análogos & derivados , Withania/metabolismo , Antineoplásicos/química , Antineoplásicos/metabolismo , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Ergosterol/biossíntese , Ergosterol/química , Frutas/química , Folhas de Planta/química , Caules de Planta/química , Estruturas Vegetais/química , Sementes/química , Withania/química , Vitanolídeos
14.
Nat Prod Res ; 23(11): 1050-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19521920

RESUMO

The fungus showing homology with Nodulisporium by 28S ribosomal gene sequencing, which has been discovered as an endophyte on medicinal plant Nothapodytes foetida, was found to produce 45 and 5.5 microg of camptothecin (CPT) per gram of mycelia at bioreactor and at shake flask, respectively, which was further quantified and characterised by various spectroscopic analyses.


Assuntos
Antineoplásicos Fitogênicos/biossíntese , Ascomicetos/metabolismo , Camptotecina/biossíntese , Antineoplásicos Fitogênicos/isolamento & purificação , Ascomicetos/genética , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/isolamento & purificação , Reatores Biológicos , Camptotecina/isolamento & purificação , DNA Fúngico/genética , Fermentação , Plantas Medicinais/microbiologia
15.
J Ethnopharmacol ; 121(2): 241-7, 2009 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-19038322

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Roots of Asparagus racemosus Willd (Shatavari in vernacular) are widely used in Ayurveda as Rasayana for immunostimulation, galactogogue as also in treatment of conditions like ulcers and cancer. Various studies have indicated immunomodulatory properties of Shatavari root extracts and formulations. AIM OF THE STUDY: To study the effect of standardized Asparagus racemosus root aqueous extract (ARE) on systemic Th1/Th2 immunity of SRBC sensitized animals. MATERIALS AND METHODS: We used HPTLC to quantify steroidal saponins (Shatavarin IV, Immunoside) and flow cytometry to study effects of ARE on Th1/Th2 immunity. SRBC specific antibody titres and DTH responses were also monitored as markers of Th2 and Th1 responses, respectively. We also studied lymphocyte proliferation. Cyclosporin, cyclophosphamide and levamisole were used as controls. RESULTS: Treatment with ARE (100mg/(kg b.w.p.o.)) resulted in significant increase of CD3(+) and CD4/CD8(+) percentages suggesting its effect on T cell activation. ARE treated animals showed significant up-regulation of Th1 (IL-2, IFN-g) and Th2 (IL-4) cytokines suggesting its mixed Th1/Th2 adjuvant activity. Consistent to this, ARE also showed higher antibody titres and DTH responses. ARE, in combination with LPS, Con A or SRBC, produced a significant proliferation suggesting effect on activated lymphocytes. CONCLUSION: The study suggests mixed Th1/Th2 activity of ARE supports its immunoadjuvant potential.


Assuntos
Asparagus/química , Extratos Vegetais/farmacologia , Células Th1/efeitos dos fármacos , Células Th2/efeitos dos fármacos , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/isolamento & purificação , Adjuvantes Imunológicos/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Cromatografia em Camada Fina , Eritrócitos/metabolismo , Citometria de Fluxo , Masculino , Ayurveda , Camundongos , Camundongos Endogâmicos BALB C , Extratos Vegetais/administração & dosagem , Raízes de Plantas , Saponinas/isolamento & purificação , Saponinas/farmacologia , Ovinos , Células Th1/imunologia , Células Th2/imunologia , Regulação para Cima/efeitos dos fármacos
16.
Eur J Med Chem ; 44(1): 229-38, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18395941

RESUMO

A quantitative structure-activity relationship (QSAR) analysis has been performed on a data set of 42 aryl alkenyl amides/imines as bacterial efflux pump inhibitors. Several types of descriptors including topological, spatial, thermodynamic, information content and E-state indices have been used to derive a quantitative relationship between the efflux pump inhibiting activity and structural properties. Algorithm based on genetic function approximation method of variable selection was used to generate the model. Statistically significant model (with r(2)=0.87) was obtained with the descriptors like radius of gyration and heat of formation besides E-state indices, AlogP atom types and solvent accessible charged surface area playing an important role in determining the activity of the compounds against bacterial efflux pump. The model was also tested successfully for external validation criteria. The model is not only able to predict the activity of new compounds but also explained the important regions in the molecules in quantitative manner.


Assuntos
Amidas/química , Proteínas de Bactérias/antagonistas & inibidores , Iminas/química , Proteínas de Membrana Transportadoras/efeitos dos fármacos , Relação Quantitativa Estrutura-Atividade , Algoritmos , Amidas/farmacologia , Bactérias/química , Iminas/farmacologia
17.
Prikl Biokhim Mikrobiol ; 44(2): 225-31, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18669267

RESUMO

The medicinal plant, Nothapodytes foetida contains a number of important alkaloids like camptothecin (an anticancer drug molecule) but its concentration is less to meet the existing demand of this important molecule, so in an effort for accessible availability of camptothecin. An endophyte (designated ZP5SE) was isolated from the seed of Nothapodytes foetida and was examined as potential source of anticancer drug lead compound i.e. camptothecin, when grown in Sabouraud liquid culture media under shake flask conditions. The presence of anticancer compound (camptothecin) in this fungus was confirmed by chromatographic and spectroscopic methods in comparison with authentic camptothecin. Isolated endophyte (Neurospora crassa) producing camptothecin may become an easily accessible source for the production of precursor anticancer drug molecule in future at large scale.


Assuntos
Antineoplásicos Fitogênicos/biossíntese , Camptotecina/biossíntese , Neurospora/metabolismo , Casca de Planta/microbiologia , Rubiaceae/microbiologia , Antineoplásicos Fitogênicos/farmacologia , Camptotecina/farmacologia , Linhagem Celular Tumoral , Humanos , Neurospora/isolamento & purificação , Filogenia
18.
J Ethnopharmacol ; 119(2): 218-24, 2008 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-18639619

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Dried flowers of Woodfordia fruticosa Kurz. Family Lythraceae are used in variety of diseases in traditional Indian system of medicine including hepatic ailments. AIMS OF STUDY: The aim of present study was to validate hepatoprotective activity of flowers of Woodfordia fruticosa Kurz. MATERIALS AND METHODS: Petroleum ether (WF1), chloroform (WF2), ethyl alcohol (WF3) and aqueous (WF4) extracts of the flowers of Woodfordia fruticosa were evaluated for hepatoprotective activity against carbon tetrachloride induced hepatotoxicity using biochemical markers, hexobarbitone sleep time, bromosulphalein (BSP) clearance test and effect on bile flow and bile solids. RESULTS: The aqueous extract (WF4) was most potent among the four extracts studied in detail. WF4 showed significant hepatoprotective activity against carbon tetrachloride induced hepatotoxicity as evident by restoration of serum transaminases, alkaline phosphatase, bilirubin and triglycerides. The restoration of microsomal aniline hydroxylase and amidopyrine-N-demethylase activities indicated the improvement in functional status of endoplasmic reticulum. Restoration of lipid peroxidation and glutathione contents suggests the antioxidant property of WF4. The recovery in bromosulphalein clearance and stimulation of bile flow suggested the improved excretory and secretary capacity of hepatocytes. Light microscopy of the liver tissue further confirmed the reversal of damage induced by hepatotoxin. CONCLUSION: Present study showed that the aqueous extract of Woodfordia fruticosa significantly restores physiological integrity of hepatocytes. WF4 did not show any sign of toxicity up to oral dose of 2g/kg in mice.


Assuntos
Antioxidantes/administração & dosagem , Hepatopatias/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Woodfordia/química , Animais , Antioxidantes/isolamento & purificação , Antioxidantes/toxicidade , Tetracloreto de Carbono , Relação Dose-Resposta a Droga , Feminino , Flores , Glutationa/efeitos dos fármacos , Glutationa/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Índia , Peroxidação de Lipídeos/efeitos dos fármacos , Testes de Função Hepática , Masculino , Medicina Tradicional , Camundongos , Extratos Vegetais/toxicidade , Ratos , Ratos Wistar , Solventes/química
19.
J Chromatogr Sci ; 46(4): 362-8, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18402730

RESUMO

Camptothecin (CPT), a monoterpene alkaloid, is an important anti-cancer compound obtained from several plant sources including Camptotheca acuminta (from China) and Nothapodytes nimmoniana (from India). Currently, by far the highest levels of CPT (approximately 0.3% w/w) are reported from Nothapodytes nimmoniana, a small tree distributed in the Western Ghats, India. In recent years because of the heavy demand, there has been a serious threat of extinction of the populations of the tree in the Western Ghats forest of south India. Several studies have chemically profiled populations of the species in the Western Ghats to identify sources of high yield and therefore to enable the sustainable production and harvesting of CPT. In this study, using both high-performance liquid chromatography and liquid chromatography-mass spectrometry, we report for the first time the identification of trees that produce at least 5- to 8-fold more CPT than hitherto reported. Furthermore, we show for the first time the production of a few minor camptothecines, including 10-hydroxy camptothecin, in the stem and root bark extracts of the tree. These results have important implications for not only harnessing the high-yielding individuals for clonal multiplication but also for exploiting some of the minor camptothecines, which also have been shown to have important anti-cancer and anti-viral activity.


Assuntos
Alcaloides/isolamento & purificação , Camptotecina/isolamento & purificação , Magnoliopsida/química , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Casca de Planta/química , Raízes de Plantas/química , Caules de Planta/química
20.
Phytomedicine ; 15(6-7): 408-15, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18424019

RESUMO

Aim of the study is to evaluate the anti-ulcer efficacy of the boswellic acids (BA), a triterpenoid known as anti-inflammatory/anti-arthritic agent, which is in clinical use. The reason for the study is that, the known non-steroidal anti-inflammatory drugs (NSAIDs) are full of side effects especially ulceration which is at the top. BA, although, used as an anti-arthritic agent yet it is not only devoid of ulcer production but protective also. The activity evaluation was done by the following universally accepted animal models viz., pyloric ligation, ethanol-HCl, acetylsalicylic acid, indomethacin and cold restrained stress-induced ulceration in rats. Results of the present study revealed that BA possess a dose dependent antiulcer effect against different experimental models. It showed different degree of inhibition of the ulcer score towards different ulcerogenic agents. The ulcer score against various ulcer inducing agents viz., pyloric ligation, ethanol/HCl, (acute and chronic) acetylsalicylic acid, indomethacin and cold restraint stress, was inhibited by 39%, 38%, 51%, 31%, 37% and 42% respectively at 250mg/kg. From the data it is concluded that BA inhibited ulcer production non-specifically in all the experimental models, whereby, it is not possible to propose a single specific mechanism. Nevertheless it is possible that BA might be acting by increasing the gastric mucosal resistance and local synthesis of cytoprotective prostaglandins and inhibiting the leukotriene synthesis.


Assuntos
Antiulcerosos/uso terapêutico , Boswellia/química , Antagonistas de Leucotrienos/uso terapêutico , Fitoterapia , Úlcera Gástrica/prevenção & controle , Triterpenos/uso terapêutico , Animais , Antiulcerosos/química , Aspirina , Etanol , Temperatura Alta , Ácido Clorídrico , Indometacina , Ligadura , Masculino , Ratos , Ratos Wistar , Úlcera Gástrica/induzido quimicamente , Triterpenos/química
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