Recursos de colección

Universidad Nacional de La Plata (74.783 recursos)

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vol. 30, no. 04

Mostrando recursos 1 - 20 de 32

  1. Validation of a high performance liquid chromatographic method for quantitative determination of boldine in fluid extract of boldo

    Casal, Francieli; Mallmann, Michele; Pedroni, Helen C.; Grazziotin, Manoela M.; Tasso, Leandro
    A simple and specific method was validated for quantification of boldine in fluid extract of boldo (Peumus boldus Mol.) using high-performance liquid chromatography. A reversed-phase C18 , Phenomenex® (150 x 4.6 mm, 4 µm) column was employed. The mobile phase consisted of 0.1 % trifluoroacetic acid and acetonitrile (78:22, v/v) at a flow rate of 0.8 mL/min. The column was maintained at 30 °C and the boldine peak detection was performed at a wavelength of 281 nm. The parameters used in the validation process were: linearity, specificity, precision, accuracy, limit of detection, limit of quantification and robustness. The validated method was selective and linear (r≥0.9991)...

  2. Leaf and stem morpho-anatomy of Cordia americana (L.) Gottschling & J.S. Mill., Boraginaceae

    Ló, Stella M. S.; Duarte, Márcia do Rocio
    Cordia americana (L.) Gottschling & J.S. Mill. is a tree which belongs to the Boraginaceae family and is native to the South of Brazil, Paraguay and Argentine, where it is commonly known as guajuvira and guayaibí. In folk medicine, the leaves are used as emollient, antimicrobial and anti-inflammatory, as well as the stem has antidiarrheal and hepatoprotective effects. Preliminary phytochemical studies have shown the presence of tannins, coumarins, quinones and cinnamaldehyde derivatives. This work has investigated the leaf and stem morpho-anatomy of C. americana, in order to contribute to the pharmacognostic quality control. Samples of adult leaves and young stems...

  3. Anti-inflammatory activity of leaves of Michelia champaca investigated on acute inflammation induced rats

    Gupta, Sumeet; Mehla, Kritika; Chauhan, Devesh; Nair, Anroop
    Natural products play a significant role in human health in relation to the prevention and treatment of inflammation conditions. Although not fully understood, several action mechanisms are proposed to explain in vivo inflammatory action. The aim of this study was to assay different extracts from leaves of Michelia champaca (Magnoliaceae) on carrageenan induced inflammation rat model. The results were analyzed by One Way Analysis of Variance (ANOVA). The ethanolic extract (200 mg/kg) was found to be highly significant (p < 0.0001) with maximum inhibition (60.99 %) at 3 h against to positive control group. The findings conclude that M. champaca...

  4. Stem morphoanatomy of Poiretia tetraphylla (Poiret) Burkart (Leguminosae)

    Royer, Lauri A.J.; Necchi, Raquel M.M.; Marín, Aline; Zanetti, Gilberto Dolejal; Manfron, Melânia Palermo
    Poiretia tetraphylla is an erect herb to subshrub, perennial, native to Brazil, Argentina, Paraguay and Uruguay. It is popularly known as erva-de-touro-miúda and used in traditional medicine as tonic, in stomach disorders and verminosis. The stem is angular, striate, glabrous with copious amounts of oblong and translucent glands. The epidermis is uniestratified and persistent, stomata well pronounced, thick, smooth and plain cuticle and oval mucilaginous glandular formations. The cortex has parenchyma cells, and the innermost layer is distinguished from others by having large cells with little cytoplasmic content. In this region, protecting the phloem, has a group up to six layers of sclerenchyma fibers. The...

  5. Antioxidant, allelopathic and toxic activity of Ochna serrulata

    Colla, Guilherme; Brighente, Inês Maria Costa; Queiroz, Gustavo S.; Silva, Mariana A. da; Pizzolatti, Moacir Geraldo
    Ochna serrulata (Ochnaceae) is an ornamental plant introduced into Brazil from Asia and Africa. Species of the Ochna genus are rich in phenolic compounds, mainly flavonoids. The biological screening of extracts and fractions showed that this plant exhibited a significant antioxidant activity, when evaluated by the DPPH and reducing potential assays. Ochna serrulata also demonstrated slight toxic activity against Artemia salina and a potential inhibitory allelopathic activity, when evaluated using the Lactuca sativa seed germination test. The ethyl acetate fraction, the most active one, was partitioned on a silica gel column to obtain epicatechin, which showed potential antioxidant activity.

  6. Physicochemical and phytochemical control of Arrabidaea chica (H. & B.) Verlot leaf powder and standardized tincture

    Alves, Mauro M. S.; Mendes, Patrizia C.; Vieira, Janaína G. P.; Jardim, Mário A. G.; Ozela, Eliana F.; Costa, Roseane M.R.; Barbosa, Wagner L.R.; Silva Júnior, José O. C.
    The quality control of herbal drugs and their intermediates is essential, especially when they are used as feedstock for medicine development. This study aimed at applying the methodologies established by Brazilian legislation for the development of parameters concerning the characterization and quality control of leaf powder and tincture of Arrabidaea chica (H & B) Verlot. Known as cipó-pau (vinestick), carajeru, pariri, among others, it presents antifungal activity and is used in several diseases such as mycosis and ringworm. The physico-chemical characteristics of the plant drug. The phytochemical screening of the t inc tur e indi cat ed the pr e...

  7. Formulation and in-vitro evaluation of repaglinide microspheres prepared by spray drying technique

    Kshirsagar, Sanjay J.; Patel, Smit J.; Madgulkar, Ashwini R.; Bhalekar, Mangesh R.
    Repaglinide is a potent second generation oral hypoglycaemic agent widely used in treatment of non insulin dependent diabetic mellitus. The objective of the present study was to develop sustained release microspheres of repaglinide using ethyl cellulose and PEG 6000 as a matrix forming polymer. Microspheres were prepared by taking various concentrations of ethyl cellulose and PEG 6000 by spray drying technique. Prepared microspheres were evaluated for process yield, drug entrapment, particle size, SEM, FTIR, DSC and in vitro drug release. Process yield and drug entrapment was 40-45 % and 90-95 %, respectively. Particle size ranged in 5-22 µm and SEM study showed spherical...

  8. Development and validation of a RP-HPLC method for determination of citicoline monosodium in human plasma

    Bindaiya, Shailendra K.; Sahu, Kapendra; Bhaisare, Mukesh; Karthikeyan, Chandrabose; Moorthy, N.S.H.N.; Mehta, Farhad F.; Trivedi, Piyush
    A sensitive and specific high performance reversed phase liquid chromatographic method was developed for quantification of citicoline monosodium (CTM) in human plasma. The active drug was isocratically eluted at a flow rate of 1 ml/min at ambient temperature in a nucleosil C18 analytical column with a mobile phase composed of tetrabutyl ammonium hydro gen sulfate buffer (0.005 M, pH5.0): methanol (95:05, v/v). Photodiode array (PDA) was performed at 270 nm and the retention time of the drug was found to be 6.64 min. The lowest limit of quantification (LLOQ) and of detection (LOD) were found to be 30 and 10...

  9. Anticataleptic activity of various extracts of the aerial parts of Achyranthes aspera

    Datir, Sandip B.; Nirmal, Sunil A.; Ganjare, Anjali B.; Patil, Manohar J.; Dighe, Nachiket S.; Mandal, Subhash C.
    Achyranthes aspera is traditionally used in the treatment of cough and bronchitis and therefore it was our objective to study the effect various extracts of the plant on clonidine and haloperidol induced catalepsy to study its antihistaminic effect. Petroleum ether extract (200 mg/kg, i.p.) of the plant significantly inhibited clonidine-induced catalepsy but not inhibited haloperidol-induced catalepsy. This proves the antihistaminic activity of the plant. The extract was standardized by HPTLC in presence of standard β-sitosterol, which proves that the antihistaminic activity may be due to β-sitosterol.

  10. Antiinflammatory activity and biochemical parameters of the ethanol extract of Nopalea cochenillifera (L.) Salm-Dyck (Cactaceae)

    Necchi, Raquel M.M.; Maki, Tiago D.T.; Canto, Gizele S. do; Moresco, Rafael N.; Dalmora, Sérgio Luiz; Manfron, Melânia Palermo
    We evaluated the antiinflammatory activity of ethanol 70 % extract of Nopalea cochenillifera in a model of induction of granulomatous tissue and the kidney and liver toxicity through serum dosage in rats. During 7 days were administered orally 1.5 ml, 3 times a day, of the ethanol extract of cladodes of N. cochenillifera. We used nimesulide 5 mg/kg/day as positive control and 20 % propylene glycol as a negative control. After the treatment period, we assessed the formation of granulomas and the serum levels of AST, ALT, albumin, creatinine and urea in all groups, noting that the animals treated with the extract showed 53.5 % inhibition...

  11. In vitro antioxidant, reducing power, free radical scavenging and membrane stabilizing activities of seeds of Syzygium cumini L.

    Rahman, Mohammad S.; Rashid, Mohammad A.; Sikder, Al Amin; Rahman, Arifur; Kaisar, Mohammad A.; Hasan, Choudhury M.
    Different extractives of Syzygium cumini seeds were evaluated by free radical (DPPH) scavenging assay, phosphomolybdenum total antioxidant assay and reducing power determination in order to identify promising sources of antioxidants along with its membrane stabilizing activity. The total phenolic content was also determined and expressed in gallic acid equivalent. Here, butylated hydroxytoluene (BHT) and ascorbic acid (ASA) were used as standard antioxidants. The membrane stabilizing activity was assessed by using erythrocytes in hypotonic solution and was compared with acetyl salicylic acid. A positive correlation was observed between total phenolic content and total antioxidant activity as well as reducing power of...

  12. QSAR analysis of structurally similar antitubercular isatin analogues

    Sawant, Ramesh L.; Wadekar, Jyoti B.; Lanke, Prashant D.
    A series of structurally similar isatin analogues with antitubercular activity have been subjected for 2D and 3D QSAR analysis using V life MDS 3.5 software. The compounds were divided into training and test set of 44 and 11 each. Best QSAR models were selected on the basis of various statistical parameters like square correlation coefficient (2 ), cross validated square correlation coefficient (q2 ), standard error of estimation (SE) and sequential Fischer test (F). QSAR studies reveals that new isatin analogues with less bulky substitution on nitrogen of first position and at third position electropositive side chain of optimum four...

  13. Development of nanoencapsulation forms from Cymbopogon citratus essential Oil

    Falcão, Deborah Q.; Santos, Arith R.; Ortiz Silva, Bianca; Louro, Ricardo P.; Seiceira, Rafael; Finotelli, Priscilla V.; Ferreira, José Luis P.; De Simone, Salvatore G.; Amaral, Ana C. F.
    Cymbopogon citratus essential oil (CCEO) is widely used in food, cosmetics and pharmaceutical fields. The aim of this study was to compare two different methods of encapsulating CCEO. The o/w emulsion method was employed here for the first time for producing CCEO nanoparticles with polycaprolactone (PCL) and a molecular inclusion in β-cyclodextrin (CyD) using the precipitation method. The nanoparticles were spherical in shape, with 240.0 nm mean diameter and demonstrated a higher encapsulation efficiency (36.51 %) as the citral content. The efficiency of CCEO/CyD complex was lower (9.46 %) and it showed some specificity for the smallest molecules present in...

  14. Antibacterial activity of two pregnenolone-derivatives against Vibrio cholerae and Escherichia coli and its relationship with descriptors LogP, Π

    Figueroa, Lauro; Díaz, Francisco; López, María; Camacho, Abelardo; García, Elodia; Ozaeta, Rolando
    In this work the antibacterial activity of two pregnenolone-derivatives was evaluated on V. cholerae and E. coli, using a NCCLS broth dilution modified method. Additionally, to delineate the structural chemical requirements of the steroid derivatives as antibacterial agents on E. coli and V. cholerae, other parameters such as the physicochemical descriptors LogP and π were calculated. The results obtained indicate that bacterial growth of E. coli and V. cholerae was inhibited with pregnenolone-vitamin B1 (MIC = 6.64. x 10-4 mmol/mL) and pregnenolone-carbamazepine (MIC = 3.18 x 10-4 mmol/mL). Other results showed an increase in LogP and π values in the...

  15. Simultaneous determination of olmesartan medoxomil and amlodipine besylate in pharmaceutical formulations by capillary zone electrophoresis

    Çelebier, Mustafa; Süslü, Incilay; Altinöz, Sacide
    A simple, efficient and reliable capillary zone electrophoresis method with diode array detection was developed and validated for the simultaneous determination of olmesartan medoxomil and amlodipine besylate in their binary mixtures. The optimum separation for these compounds was achieved with a fused - silica capillary column (i.d. 75.0 µm, total length 48.5 cm and effective length 40.0 cm) and 40.0 mM citrate buffer at pH 6.0 as the running buffer. The samples were injected hydrodynamically for 3 s at 50 mbar and applied voltage was + 15 kV at 30 °C capillary temperature. Detection wavelength was set at 235 nm....

  16. Quantitative determination of gemifloxacin mesylate in tablets by capillary zone electrophoresis and high performance liquid chromatography

    Tavares, Vanessa F.; Patto, Daniela C.S.; Singh, Anil K.; Prado, Maria S. A.; Kedor-Hackmann, Erika R.M.; Santoro, Maria Ines Rocha Miritello
    The aim of this study was to develop and validate selective and sensitive methods for quantitative determination of an antibacterial agent, gemifloxacin, in tablets by high performance liquid chromatography (HPLC) and capillary zone electrophoresis (CZE). The HPLC method was carried out on a LiChrospher® 100 RP-8e, 5 μm (125 x 4 mm) column with a mobile phase composed of tetrahydrofuranwater (25:75, v/v) with 0.5 % of triethylamine and pH adjusted to 3.0 with orthophosphoric acid. The CZE method was performed using 50 mM sodium tetraborate buffer (pH 8.6). Samples were injected hydrodynamicaly (0.5 psi, 5 s) and the electrophoretic system...

  17. Determination of 5-fluorouracil in surface samples using SPE combined with HPLC- DAD

    Resende, Renata C.; Tahan, Gabriella P.; Oliveira, Antônio F.F.; Maia, Patrícia P.; Martins, Isarita
    A simple and rapid SPE-HPLC-DAD method was developed for the determination of 5-fluorouracil (5-FU) in surface samples. A C18 column (250 x 4.6 mm i.d., 5 µm) and a similar pre-column were used for the separation at 25 ºC, using 20 mM ammonium acetate buffer solution pH 4.7: methanol (95:5, v/v) as mobile phase at a flow rate of 1.2 mL/min. Under optimal conditions, the linearity was 0.9993, in a range of 25-100 µg/mL. The limits of detection and quantification were 5 and 25 µg/mL, respectively. The relative standard deviation (%) was below 15 % for the evaluation of precision and the mean recovery...

  18. Development and in vitro evaluation of propranolol hydrochloride controlled release tablets using HPMC as matrix former

    Villanova, Janaina C.O.; Consiglieri, Vladi
    The purpose of this paper was to produce controlled-release matrices with 120 mg of propranolol hydrochloride (PHCl) employing hydroxypropyl methylcellulose (HPMC, Methocel® K100) as the gel forming barrier. Although this class of polymers has been commonly used for direct compression, with the intent of use reduced polymer concentrations to achieve controlled drug release, in this study tablets were produced by the wet granulation process. HPMC percentages ranged from 15-34 % and both soluble and non soluble diluents were tested in the 10 proposed tablet compositions. Dissolution testing of matrices was performed over a 12 h period in 1.2 pH medium...

  19. Formulation and evaluation of multilayered matrix tablets of diltiazem hydrochloride

    Mangamoori, Lakshmi N.; Yamsani, Madhusudan R.
    In the present study matrix and multilayered matrix tablets of diltiazem HCl were formulated by using guar gum as matrix core component and cellulose derivative, Sodium Carboxy Methyl Cellulose (SCMC) as barrier layers. Marked difference in dissolution characteristics of D3 and D3L3 was observed and showed a statistically significant difference. The study revealed that the matrix tablets prolonged the release, but predominantly in a first order fashion. Layering with SCMC granules on the matrix core, provided linear drug release with zero order kinetics. Mean dissolution time for D3 and D3L3 were found to be 4.17 h and 16.45 h, while...

  20. Simultaneous determination of Choline citrate and acetylmethionine in injectable solutions by high performance liquid chromatography

    Alexandre, Grazielle P.; Prado, Maria S. A.; Kedor-Hackmann, Erika R.M.; Singh, Anil K.; Santoro, Maria Ines Rocha Miritello
    Choline citrate (CC) and acetylmethionine (AM) are lipotropic drugs used in several pharmaceutical formulations. The objective of this research was to develop and validate a high performance liquid chromatographic (HPLC) method for simultaneous determination of CC and AM in injectable solutions, aiming its application in routine analysis for quality control of these pharmaceutical formulations. The method was validated using a Shim-Pack® C18 (250 x 4.6 mm, 5 µm) column. The mobile phase was constituted of 25 mM potassium phosphate buffer solution, pH 5.7, adjusted with 10 % orthophosphoric acid, acetonitrile and methanol (88:10:2, v/v/v). The flow rate was 1.1 mL.min-1 and the UV detection was...

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