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Bioactive compounds in Gyromitra esculenta and Helvella lacunosa wild mushrooms from Northeast of Portugal

Leal, Ana Raquel; Barros, Lillian; Martins, Anabela; Ferreira, Isabel C.F.R.
Fonte: Instituto Politécnico de Bragança Publicador: Instituto Politécnico de Bragança
Tipo: Conferência ou Objeto de Conferência
ENG
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The search for foods that can improve health or reduce the risk of disease, has been steadily gaining interest. Mushrooms could be examples of these foods because they are appreciated worldwide for their nutritional properties [1] and bioactive compounds [2]. The chemical characterization of wild species is very important, in order to promote their consumption and conserve their habitats. This feature might place mushrooms in the pharma-nutrition interface. The present study describes the bioactive compounds in two wild mushrooms ( Gyromitra esculenta and Helvelfa lacunosa edible after proper pre-boiling and cooking) collected in Bragança (Northeast Portugal). The individual profiles of organic acids and phenolic compounds were obtained by high performance liquid chromatography coupled to photodiode array detection (HPLC-PDA); tocopherols and free sugars were characterized by HPLC-fluorescence and HPLCRI (refraction index), respectively, and the fatty acids profile was obtained by gas chromatography coupled to flame ionization detection (GC-FID). Gyromitra esculenta was the species with the highest levels of free sugars (6.13 g/1 OOg dw), tocopherols ( 112.83 IJg/1 OOg dw) and phenolic compounds (3.74 mg/1 OOg dw). The major fatty acid found in this specie was linoleic acid (prevalence of PUFA)...

A multi-screening approach for marine-derived fungal metabolites and the isolation of cyclodepsipeptides from Beauveria felina

VITA-MARQUES, Aline Maria de; LIRA, Simone P.; BERLINCK, Roberto G. S.; SELEGHIM, Mirna H. R.; SPONCHIADO, Sandra R. P.; TAUK-TORNISIELO, Sâmia M.; BARATA, Margarida; PESSOA, Claudia; MORAES, Manoel O. de; CAVALCANTI, Bruno Coêlho; NASCIMENTO, Gislene G
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica
ENG
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Extracts obtained from 57 marine-derived fungal strains were analyzed by HPLC-PDA, TLC and ¹H NMR. The analyses showed that the growth conditions affected the chemical profile of crude extracts. Furthermore, the majority of fungal strains which produced either bioactive of chemically distinctive crude extracts have been isolated from sediments or marine algae. The chemical investigation of the antimycobacterial and cytotoxic crude extract obtained from two strains of the fungus Beauveria felina have yielded cyclodepsipeptides related to destruxins. The present approach constitutes a valuable tool for the selection of fungal strains that produce chemically interesting or biologically active secondary metabolites.; FAPESP; National Institutes of Health NIH-NCI NCDDG; Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES); CNPq

Acaricidal action of destruxins produced by a marine-derived Beauveria felina on the bovine tick Rhipicephalus (Boophilus) microplus

Morais-Urano, Raquel P.; Chagas, Ana C. S.; Berlinck, Roberto Gomes de Souza
Fonte: ACADEMIC PRESS INC ELSEVIER SCIENCE; SAN DIEGO Publicador: ACADEMIC PRESS INC ELSEVIER SCIENCE; SAN DIEGO
Tipo: Artigo de Revista Científica
ENG
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The increasing resistance of Rhipicephalus (Boophilus) microplus tick to commercial insecticides requires alternative methods for the control of this cattle plague. The enthomopathogenic fungus Beauveria feline produces destruxins in culture media, cyclic depsipeptides which display an array of biological activities. The present investigation aimed to evaluate the acaricide action of destruxins isolated from B. felina culture media on R. (B.) microplus engorged females. B. felina was grown in MF medium under 19 different growth conditions. HPLC-PDA analysis of chromatographic fractions obtained from the 19 different growth media extracts indicated the presence of destruxins in all lipophylic fractions. Such fractions were combined and subjected to separation by HPLC. Fractions containing distinct destruxins composition were tested against R. (B.) micro plus. Two fractions, composed of destruxin Ed(1) and pseudodestruxin B and/or pseudodestruxin C (fraction P1) as well as by hydroxyhomodestruxin B and/or destruxin D and/or roseotoxin C (fraction P7), displayed 30% and 28.7% acaricidal efficacy, respectively. This activity profile in such low concentration is adequate to consider destruxins as potential leading compounds to be developed for tick biological control. (C) 2012 Elsevier Inc. All rights reserved.; FAPESP (BIOTA/BIOprospecTA) [2010/50190-2]; FAPESP (BIOTA/BIOprospecTA); Embrapa [03.11.01.023.00.00]; Embrapa; CNPq; CNPq

Chemical Composition of the Bark of Tetrapterys mucronata and Identification of Acetylcholinesterase Inhibitory Constituents

Ferreira Queiroz, Marcos Marcal; Queiroz, Emerson Ferreira; Zeraik, Maria Luiza; Ebrahimi, Samad Nejad; Marcourt, Laurence; Cuendet, Muriel; Castro-Gamboa, Ian; Hamburger, Matthias; Bolzani, Vanderlan da Silva; Wolfender, Jean-Luc
Fonte: Amer Chemical Soc Publicador: Amer Chemical Soc
Tipo: Artigo de Revista Científica Formato: 650-656
ENG
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Processo FAPESP: 10/09780-0; The secondary metabolite content of Tetrapterys mucronata, a poorly studied plant that is used occasionally in Brazil for the preparation of a psychotropic plant decoction called Ayahuasca, was determined to establish its chemical composition and to search for acetylcholinesterase (AChE) inhibitors. The ethanolic extract of the bark of T. mucronata exhibited in vitro AChE inhibition in a TLC bioautography assay. To localize the active compounds, biological profiling for AChE inhibition was performed using at-line HPLC-microfractionation in 96-well plates and subsequent AChE inhibition bioautography. The analytical HPLC-PDA conditions were transferred geometrically to a preparative medium-pressure liquid chromatography column using chromatographic calculations for the efficient isolation of the active compounds at the milligram scale. Twenty-two compounds were isolated, of which six are new natural products. The structures of the new compounds (9, 10, 16-18, and 20) were elucidated by spectroscopic data interpretation. Compounds 1, 5, 6, 9, and 10 inhibited AChE with IC50 values below 15 mu M.

Chemical characterization and biological activity of the Ceylon gooseberry (Dovyalis hebecarpa) in different ripening stages= : Caracterização química e atividade biológica da groselha do ceilão (Ddovyalis hebecarpa) em diferentes estadios de maturação; Caracterização química e atividade biológica da groselha do ceilão (Dovyalis hebecarpa) em diferentes estadios de maturação

Vivian Caetano Bochi
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 26/07/2013 PT
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A groselha do Ceilão (Dovyalis hebecarpa) é uma fruta exótica de coloração roxa quando madura. Não foram encontrados trabalhos que identifiquem os principais compostos fenólicos na espécie, ação antioxidante e efeitos biológicos. Sendo assim, além da otimização da extração, esse trabalho avaliou os principais compostos fenólicos na casca e polpa de D. hebecarpa por cromatografia líquida acoplada a espectrômetro de massas (CLAE-DAD-EM), o potencial antioxidante in vitro e o efeito sobre a resposta imunológica em camundongos. Com exceção da razão entre amostra e solvente, avaliada univariadamente, a otimização das variáveis de extração foi realizada utilizando planejamento experimental multivariado. O processo otimizado foi realizado em menor tempo (20 minutos), com menos solvente orgânico (20% de acetona) e com maior rendimento (aumento de 10% no teor total de compostos fenólicos e de 26% no teor total de antocianinas monoméricas) do que a metodologia inicial. A caracterização do perfil de antocianinas revelou que D. hebecarpa é fonte de compostos não acilados, sendo delfinidina-3-O-rutinosídeo e cianidina-3-O-rutinosídeo os majoritários. Casca e polpa possuem composição similar, no entanto, maiores concentrações são encontradas na parte externa do fruto. Amostras de dois anos consecutivos e em duas datas de amostragem foram recolhidas para avaliação de variações entre estações do ano. Considerando que a ação antioxidante se dá por diversos mecanismos...

Development and validation of a dissolution method using HPLC for diclofenac potassium in oral suspension

Rubim,Alexandre Machado; Rubenick,Jaqueline Bandeira; Laporta,Luciane Varini; Rolim,Clarice Madalena Bueno
Fonte: Universidade de São Paulo, Faculdade de Ciências Farmacêuticas Publicador: Universidade de São Paulo, Faculdade de Ciências Farmacêuticas
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2014 EN
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The present study describes the development and validation of an in vitro dissolution method for evaluation to release diclofenac potassium in oral suspension. The dissolution test was developed and validated according to international guidelines. Parameters like linearity, specificity, precision and accuracy were evaluated, as well as the influence of rotation speed and surfactant concentration on the medium. After selecting the best conditions, the method was validated using apparatus 2 (paddle), 50-rpm rotation speed, 900 mL of water with 0.3% sodium lauryl sulfate (SLS) as dissolution medium at 37.0 ± 0.5°C. Samples were analyzed using the HPLC-UV (PDA) method. The results obtained were satisfactory for the parameters evaluated. The method developed may be useful in routine quality control for pharmaceutical industries that produce oral suspensions containing diclofenac potassium.

Cimicifuga species identification by high performance liquid chromatography-photodiode array/mass spectrometric/evaporative light scattering detection for quality control of black cohosh products

He, Kan; Pauli, Guido F.; Zheng, Bolin; Wang, Huikang; Bai, Naisheng; Peng, Tangsheng; Roller, Marc; Zheng, Qunyi
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
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Black cohosh has become one of the most important herbal products in the U.S. dietary supplements market. It is manufactured from roots and rhizomes of Cimicifuga racemosa (Ranunculaceae). Botanical identification of the raw starting material is a key step in the quality control of black cohosh preparations. The present report summarizes a fingerprinting approach based on HPLC-PDA/MS/ELSD that has been developed and validated using a total of ten Cimicifuga species. These include three North American species, C. racemosa, C. americana, C. rubifolia, and seven Asian species, C. acerina, C. biternat, C. dahurica, C. heracleifolia, C. japonica, C. foetida, and C. simplex. The chemotaxonomic distinctiveness of the HPLC fingerprints allows identification of all ten Cimicifuga species. The triterpene glycosides cimigenol-3-O-arabinoside (3), cimifugin (12), and cimifugin-3-O-glucoside (18) were determined to be suitable species-specific markers for the distinction of C. racemosa from the other Cimicifuga species. In addition to identification, the fingerprint method provided insight into chemical interconversion processes occurring between the diverse triterpene glycosides contained in black cohosh. The reported method has proven its usefulness in the botanical standardization and quality control of black cohosh products.

Optimization of Lycopene Extraction from Tomato Cell Suspension Culture by Response Surface Methodology

Lu, Chi-Hua; Engelmann, Nancy J.; Lila, Mary Ann; Erdman, John W.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
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Radioisotope-labeled lycopene is an important tool for biomedical research but currently is not commercially available. A tomato cell suspension culture system for the production of radioisotope-labeled lycopene was previously developed in our laboratory. In the current study, the goal was to optimize the lycopene extraction efficiency from tomato cell cultures for preparatory high-performance liquid chromatography (HPLC) separation. We employed response surface methodology (RSM), which combines fractional factorial design and a second-degree polynomial model. Tomato cells were homogenized with ethanol, saponified by KOH, and extracted with hexane, and the lycopene content was analyzed by HPLC-PDA. We varied five factors at five levels: ethanol volume (1.33–4 mL/g); homogenization period (0–40 s/g); saturated KOH solution volume (0–0.67 mL/g); hexane volume (1.67–3 mL/g); and vortex period (5–25 s/g). Ridge analysis by SAS suggested that the optimal extraction procedure to extract 1 g of tomato cells was at 1.56 mL of ethanol, 28 s homogenization, 0.29 mL of KOH, 2.49 mL of hexane, and 17.5 s vortex. These optimal conditions predicted by RSM were confirmed to enhance lycopene yield from standardized tomato cell cultures by more than 3-fold.

Identification of GABA A receptor modulators in Kadsura longipedunculata and assignment of absolute configurations by quantum-chemical ECD calculations

Zaugg, Janine; Ebrahimi, Samad Nejad; Smiesko, Martin; Baburin, Igor; Hering, Steffen; Hamburger, Matthias
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
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A petroleum ether extract of Kadsura longipedunculata enhanced the GABA-induced chloride current (IGABA) by 122.5 ± 0.3% (n = 2) when tested at 100 μg/ml in Xenopus laevis oocytes expressing GABA A receptors (α1β2γ2S subtype) in two-microelectrode voltage clamp measurements. Thirteen compounds were subsequently identified by HPLC-based activity profiling as responsible for GABA A receptor activity and purified in preparative scale. 6-Cinnamoyl-6,7-dihydro-7-myrceneol and 5,6-dihydrocuparenic acid were thereby isolated for the first time. The determination of the absolute stereochemistry of these compounds was achieved by comparison of experimental and calculated ECD spectra. All but one of the 13 isolated compounds from K. longipedunculata potentiated IGABA through GABA A receptors composed of α1β2γ2S subunits in a concentration-dependent manner. Potencies ranged from 12.8 ± 3.1 to 135.6 ± 85.7 μM, and efficiencies ranged from 129.7 ± 36.8% to 885.8 ± 291.2%. The phytochemical profiles of petroleum ether extracts of Kadsura japonica fruits (114.1 ± 2.6% potentiation of IGABA at 100 μg/ml, n = 2), and Schisandra chinensis fruits (inactive at 100 μg/ml) were compared by HPLC-PDA-ESIMS with that of K. longipedunculata.

Comparative Characterization of Total Flavonol Glycosides and Terpene Lactones at Different Ages, from Different Cultivation Sources and Genders of Ginkgo biloba Leaves

Yao, Xin; Shang, Erxin; Zhou, Guisheng; Tang, Yuping; Guo, Sheng; Su, Shulan; Jin, Chun; Qian, Dawei; Qin, Yong; Duan, Jin-Ao
Fonte: Molecular Diversity Preservation International (MDPI) Publicador: Molecular Diversity Preservation International (MDPI)
Tipo: Artigo de Revista Científica
Publicado em 17/08/2012 EN
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The extract from Ginkgo biloba leaves has become a very popular plant medicine and herbal supplement for its potential benefit in alleviating symptoms associated with peripheral vascular disease, dementia, asthma and tinnitus. Most research on G. biloba leaves focus on the leaves collected in July and August from four to seven year-old trees, however a large number of leaves from fruit cultivars (trees older than 10 years) are ignored and become obsolete after fruit harvest season (November). In this paper, we expand the tree age range (from one to 300 years) and first comparatively analyze the total flavonol glycosides and terpene lactones at different ages, from different cultivation sources and genders of G. biloba leaves collected in November by using the validated HPLC-ELSD and HPLC-PDA methods. The results show that the contents of total terpene lactones and flavonol glycosides in the leaves of young ginkgo trees are higher than those in old trees, and they are higher in male trees than in female trees. Geographical factors appear to have a significant influence on the contents as well. These results will provide a good basis for the comprehensive utilization of G. biloba leaves, especially the leaves from fruit cultivars.

Metabolic Profiling of Echinacea Genotypes and a Test of Alternative Taxonomic Treatments

Wu, Lankun; Dixon, Philip M.; Nikolau, Basil J.; Kraus, George A.; Widrlechner, Mark P.; Wurtele, Eve Syrkin
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
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The genus Echinacea is used as an herbal medicine to treat a variety of ailments. To better understand its potential chemical variation, 40 Echinacea accessions encompassing broad geographical and morphological diversity were evaluated under controlled conditions. Metabolites of roots from these accessions were analyzed by HPLC-photo diode array (HPLC-PDA), GC-MS, and multivariate statistical methods. In total, 43 lipophilic metabolites, including 24 unknown compounds, were detected. Weighted principal component analysis (WPCA) and clustering analysis of the levels of these metabolites across Echinacea accessions, based on Canberra distances, allowed us to test two alternative taxonomic treatments of the genus, with the further goal of facilitating accession identification. A widely used system developed by McGregor based primarily on morphological features was more congruent with the dendrogram generated from the lipophilic metabolite data than the system more recently developed by Binns et al. Our data support the hypothesis that Echinacea pallida is a diverse allopolyploid, incorporating the genomes of Echinacea simulata and another taxon, possibly Echinacea sanguinea. Finally, most recognized taxa of Echinacea can be identified by their distinct lipophilic metabolite fingerprints.

Protective effect of Zhuyeqing liquor, a Chinese traditional health liquor, on acute alcohol-induced liver injury in mice

Gao, Hong-ying; Huang, Jian; Wang, Hang-yu; Du, Xiao-wei; Cheng, Suo-ming; Han, Ying; Wang, Li-fei; Li, Guo-yu; Wang, Jin-hui
Fonte: BioMed Central Publicador: BioMed Central
Tipo: Artigo de Revista Científica
Publicado em 03/10/2013 EN
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The study first evaluated the hepatoprotective effect of Zhuyeqing Liquor (ZYQL) against acute alcohol-induced liver injury in mice. Animals were administered orally with 50% alcohol 12 ml/kg at 4 h after the doses of ZYQL everyday for fourteen consecutive days except mice in normal group. The protective effect was evaluated by biochemical parameters including serum aspartate transaminase (AST), alanine transferase (ALT), total-bilirubin (TBIL) and reduced glutathione (GSH), malondialdehyde (MDA), superoxide dismutase (SOD) in liver tissue. The result were confirmed histopathologically and the expression of TNF-α in mice liver was determined by immunohistochemistry analysis. HPLC-PDA was used for phytochemical analysis of ZYQL, and the plant source of each compound was claritied by UPLC-TOF-MS. The result showed that pretreatment with ZYQL exhibited a significant protective effect by reversing the biochemical parameters and histopathological changes in a dose depended manner. HPLC analysis indicated that ZYQL contained flavonoids, iridoids, terpenoids and phenolic acids, which might be the active chemicals. This study demonstrated the hepatoprotective activity of ZYQL, thus scientifically supported the function of its health care.

Stability-Indicating RP-HPLC Method for the Simultaneous Estimation of Doxofylline and Terbutalinesulphate in Pharmaceutical Formulations

Samanthula, Gananadhamu; Yadiki, Krishnaveni; Saladi, Shantikumar; Gutala, Sreekanth; Surendranath, K. V.
Fonte: Österreichische Apotheker-Verlagsgesellschaft Publicador: Österreichische Apotheker-Verlagsgesellschaft
Tipo: Artigo de Revista Científica
Publicado em 14/07/2013 EN
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An isocratic, stability-indicating, reversed-phase high-performance liquid chromatography (RP-HPLC) method was developed for the quantitative determination of doxofylline and terbutaline sulphate, used for the treatment of respiratory problems. The chromatographic separation was achieved on a Zorbax-SB Phenyl 250 × 4.6mm × 5 μm column with the mobile phase consisting of a mixture of 25 mM ammonium acetate (pH 5.0) : acetonitrile (85:15 %v/v) at a flow rate of 1.0 ml/min. The eluate was monitored at 274 nm using a PDA detector. Forced degradation studies were performed on the bulk sample of doxofylline and terbutaline sulphate using acid (0.1N HCl), base (0.1N NaOH), oxidation (10% hydrogen peroxide), photolytic, and thermal degradation conditions. Good resolution was observed between the degradants and analytes. Degradation products resulting from the stress studies did not interfere with the detection of doxofylline and terbutaline sulphate, thus the assay is stability-indicating. The method has the requisite accuracy, selectivity, sensitivity, and precision for the simultaneous estimation of doxofylline and terbutaline sulphate in bulk and pharmaceutical dosage forms. The limit of quantitation and limit of detection were found to be 1.16 μg/ml and 0.38 μg/ml for doxofylline...

Development and Validation of a Stability-Indicating RP-HPLC Method for the Estimation of Drotaverine Impurities in API and Pharmaceutical Formulation

Thummala, Veera Raghava Raju; Tharlapu, Satya Sankarsana Jagan Mohan; Rekulapalli, Vijay Kumar; Ivaturi, Mrutyunjaya Rao; Nittala, Someswara Rao
Fonte: Österreichische Apotheker-Verlagsgesellschaft Publicador: Österreichische Apotheker-Verlagsgesellschaft
Tipo: Artigo de Revista Científica
Publicado em 21/10/2013 EN
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A sensitive, stability-indicating gradient RP-HPLC method with PDA detection has been developed for the simultaneous analysis of drotaverine impurities in active pharmaceutical ingredient (API) and pharmaceutical formulations. Efficient chromatographic separation was achieved on an XTerra RP18, 150 × 4.6 mm, 5 μm column using gradient elution at 230 nm detection wavelength. The optimized mobile phase consisted of a 0.02 M potassium dihydrogen orthophosphate buffer of pH 3.0 as solvent A and acetonitrile as solvent B. The flow rate of the mobile phase was 1.0 mL min−1 with a column temperature of 25°C. The method showed linearity over the range of 0.251–10.033 μg/mL, 0.231–9.995 μg/mL, 0.230–10.089 μg/mL, 0.334–10.011 μg/mL, and 0.324–10.050 μg/mL for impurities 1, 2, 3, 4, and drotaverine, respectively, with a correlation coefficient greater than 0.999. The relative retention times and relative response factors of impurities 1, 2, 3, 4 were 0.36, 0.90, 1.42, 1.55 and 1.04, 0.84, 1.10, 1.30, respectively. The drotaverine formulation sample was subjected to the stress conditions of acid, base, oxidative, thermal, humidity, and photolytic degradation. Drotaverine was found to degrade significantly in peroxide, base...

Degradation Study on Sulfasalazine and a Validated HPLC-UV Method for its Stability Testing

Saini, Balraj; Bansal, Gulshan
Fonte: Österreichische Apotheker-Verlagsgesellschaft Publicador: Österreichische Apotheker-Verlagsgesellschaft
Tipo: Artigo de Revista Científica
Publicado em 12/01/2014 EN
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Sulfasalazine (SSZ) was subjected to degradation under the conditions of hydrolysis (acid, alkali, and water), oxidation (30% H2O2), dry heat, and photolysis (UV-VIS light) in accordance with the ICH guidelines. An RP-HPLC method was developed to study the degradation behavior. No degradation was noted under any condition except alkaline hydrolysis where SSZ was degraded to a single minor product. SSZ was optimally resolved from this product on an XTerra® RP18 column with a mobile phase composed of methanol and an ammonium acetate buffer (10 mM, pH 7.0) (48:52, v/v) delivered at a rate of 0.8 mL/min in an isocratic mode. The method was validated and found to be linear (r2=0.99945), precise (%RSD <2), robust, and accurate (94–102%) in the concentration range of 0.5–50 μg/mL of SSZ. The PDA analysis of the degraded sample revealed the SSZ peak purity to be 998.99 and the drug peak eluted with a resolution factor of >2 from the nearest resolving peak, indicating the method to be selectively stability-indicating for the drug analysis. The method was applied successfully for the stability testing of the commercially available SSZ tablets that were under varied ICH-prescribed conditions. An explanation for the unusual stability of the drug when exposed to acidic hydrolysis...

A simple reversed phase high-performance liquid chromatography (RP-HPLC) method for determination of curcumin in aqueous humor of rabbit

Mishra, Akhilesh; Dewangan, Gayatri; Singh, W Ramdas; Hazra, Sarbani; Mandal, Tapan Kumar
Fonte: Medknow Publications & Media Pvt Ltd Publicador: Medknow Publications & Media Pvt Ltd
Tipo: Artigo de Revista Científica
Publicado em //2014 EN
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This article describes a simple and rapid method for determination of curcumin (diferuloylmethane) in aqueous humor of rabbit using high-performance liquid chromatography (HPLC). Analysis was performed using a C-18 column (250 × 4.6 mm, 5 μ luna) by isocratic elution with a mobile phase containing 25 mM potassium dihydrogen orthophosphate (pH 3.5): Acetonitrile (40:60) and detection at 424 nm using a photodiode array (PDA) detector for curcumin. The regression data for curcumin showed a good linear relationship with r2> 0.998 over the concentration range of 0.1-10 μg ml−1. Relative standard deviations (RSD) for the intraday and interday coefficient of variations for the assay were less than 5.0 and 8.5, respectively. The recovery of the method was between 79.8-83.6%. The quantification limit of the method for curcumin was 0.01 μg ml−1. This method has good accuracy, precision, and quantitation limit. It is also concluded that the method is useful for measuring very low curcumin concentrations in aqueous humor.

Echinacea purpurea (L.) Moench modulates human T-cell cytokine response☆

Fonseca, Fabiana N.; Papanicolaou, Genovefa; Lin, Hong; Lau, Clara B.S.; Kennelly, Edward J.; Cassileth, Barrie R.; Cunningham-Rundles, Susanna
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
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The study objective was to evaluate the composition of a neutral and weakly acidic water-soluble extract from Echinacea purpurea (L.) Moench (EchNWA) previously shown to modify murine influenza infection, and to assess immunomodulatory effects on human T-cells. EchNWA extract from fresh aerial parts was extracted with water, ethanolic precipitation, and size-exclusion chromatography. The chemical profile of EchNWA was characterized by chromatography (size-exclusion, HPLC, GC–MS), and small molecule finger-print analysis performed by HPLC–PDA. Jurkat T-cells at high and low cell density were pretreated or not with doses of EchNWA, followed by activation with phorbol 12-myristate 13-acetate plus ionomycin (PMA+I). Interleukin-2 (IL-2) and interferon gamma (IFNg) cytokine secretions were measured by multi-cytokine luminex technology. Results showed that EchNWA contains 80% polysaccharides, predominantly a 10 kDa entity; phenolic compounds, cynarin, cichoric and caftaric acids, but no detectable alkylamides. Cytokine production required stimulation and was lower after PMA+I activation in high-density compared to low-density conditions. EchNWA mediated a strong dose-dependent enhancement of high-density T-cell production of IL-2 and IFNg response to PMA+I. EchNWA alone did not stimulate T-cells. EchNWA enhanced mean fluorescence intensity of IL-2 in Jurkat T-cells activated by PMA+1 or ionomycin alone. Conversely EchNWA mediated modest but significant suppression of IFNg response and reduced the percentage of CD25+ T-cells under low-density conditions. Conclusions are that EchNWA polysaccharides...

Establishment of Hairy Root Cultures of Rhaponticum carthamoides (Willd.) Iljin for the Production of Biomass and Caffeic Acid Derivatives

Skała, Ewa; Kicel, Agnieszka; Olszewska, Monika A.; Kiss, Anna K.; Wysokińska, Halina
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
EN
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The aim of the study was to obtain transformed roots of Rhaponticum carthamoides and evaluate their phytochemical profile. Hairy roots were induced from leaf explants by the transformation of Agrobacterium rhizogenes strains A4 and ATCC 15834. The best response (43%) was achieved by infection with A4 strain. The effects of different liquid media (WPM, B5, SH) with full and half-strength concentrations of macro- and micronutrients on biomass accumulation of the best grown hairy root line (RC3) at two different lighting conditions (light or dark) were investigated. The highest biomass (93 g L−1 of the fresh weight after 35 days) was obtained in WPM medium under periodic light. UPLC-PDA-ESI-MS3 and HPLC-PDA analyses of 80% aqueous methanol extracts from the obtained hairy roots revealed the presence of eleven caffeoylquinic acids and their derivatives and five flavonoid glycosides. The production of caffeoylquinic acids and their derivatives was elevated in hairy roots grown in the light. Only light-grown hairy roots demonstrated the capability for the biosynthesis of such flavonoid glycosides as quercetagetin, quercetin, luteolin, and patuletin hexosides. Chlorogenic acid, 3,5-di-O-caffeoylquinic acid and a tentatively identified tricaffeoylquinic acid derivative were detected as the major compounds present in the transformed roots.

Bioreactor design for scaleup of Catharanthus roseus hairy root cultures for production of indole alkaloids

Vani, Sundeep N.
Fonte: Universidade Rice Publicador: Universidade Rice
Tipo: Thesis; Text Formato: application/pdf
ENG
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C. roseus is the source of the important anticancer indole alkaloids, vincristine and vinblastine. Hairy root cultures are an attractive alternative for the production of plant derived secondary metabolites. C. roseus hairy root cultures were established in our laboratory by A. rhizogenes mediated transformation of C. roseus seedlings prior to the beginning of this project. The objectives of this project were twofold: (i) Alkaloid analysis of C. roseus hairy root cultures, (ii) Scaleup of hairy root cultures from shake flasks to bioreactors. An extraction method was adapted for the rapid quantification of C. roseus hairy root extracts, and was used for quantifying alkaloid yields from five different root clones. Optimum analytical wavelengths were chosen for quantification after analyzing chromatograms at five different wavelengths using PDA detection. Extracts were analyzed using different analytical techniques--GC/MS, MS, HPLC-PDA and TLC--and several alkaloids were identified. The presence of ajmalicine, akuammine, apparicine, catharanthine, hoerhammericine, lochnericine, serpentine and tabersonine was confirmed. The presence of vindoline--an important precursor of vinblastine and vincristine--could not be confirmed although GC/MS indicated the presence of vindoline fragment ions. A novel method based on non-linear regression analysis was developed for online measurement of oxygen uptake rates. Thus...

New Validated Stability-Indicating Rp-HPLC Method for Simultaneous Estimation of Atorvastatin and Ezetimibe in Human Plasma by Using PDA Detector

Kumar, S. Ashutosh; Debnath, Manidipa; Rao, J.V.L.N. Seshagiri; Sankar, D. Gowri
Fonte: Tabriz University of Medical Sciences Publicador: Tabriz University of Medical Sciences
Tipo: Artigo de Revista Científica
EN
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Purpose: This paper describes a simple, precise and accurate RP-HPLC method for simultaneous estimation of atorvastatin and ezetimibe in plasma.