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1.
Adv Pharm Bull ; 8(1): 157-161, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29670851

RESUMO

Purpose: To determine and quantify vinblastine in different varieties of Catharanthus roseus using reversed-phase HPLC method. Methods: The liquid chromatographic separation was performed using a reversed phase C18, Microsorb - MV column (250 mm x 4.6 mm, 5 µm) at room temperature and eluted with a mobile phase containing methanol - phosphate buffer (5 mM, pH 6.0) - acetonitrile with different proportion gradient elution at a flow rate of 2.0 mL min-1 and detection at 254 nm. Results: The HPLC method was utilized for the quantification of vinblastine in purple, red and white varieties of Catharanthus roseus leaves. The separation was achieved in less than 8 min. The peak confirmation was done based on the retention times and UV spectra of the reference substance. The method was validated with respect to linearity, precision, recovery, limit of detection and quantification. Results showed that the purple variety gives 1.2 and 1.5 times more vinblastine concentration compared to the white and pink varieties, respectively. Conclusion: The obtained results from different varieties are thus useful for the purpose of vinblastine production from Catharanthus roseus plant.

2.
Adv Pharm Bull ; 7(2): 313-321, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28761834

RESUMO

Purpose: To describe a chemoenzymatic approach joining an enzymatic regioselective hydrolysis of peracetylated N-acetyl-α-D-glucosamine (A) with a mild controlled acyl relocation which resulted 2-acetamido-2 deoxy-1,3,6-tri-O-acetyl-α-D-glucopyranose (1B). Methods: Immobilization of lipase on decaoctyl (DSEOD) and octyl-agarose (OSCL) was carried out as reported by the work of Bastida et al. The newly developed RP-HPLC method for examining the enzymatic hydrolysis was carried out isocratically utilizing a HPLC system. Results: The new approach resulted the target compound (B) in 95% yield after purification utilizing flash column chromatography. Candida rugosa-lipase immobilized ondecaoctyl-sepabeads was the best catalyst in terms of activity and region-selectivity in the hydrolysis of substrate (A), delivering the deacetylation at C6 position (98% general yield). Also, a reversed-phase high-performance liquid-chromatographic (RP-HPLC) method for controlling the region-selective hydrolysis of peracetylated N-acetyl-α-D-glucosamine (A) with a mild monitored acyl movement which led to 2-acetamido-2-deoxy-1,3,6-tri-O-acetyl-α-D-glucopyranose (1B) has additionally been developed. The developed RP-HPLC method was utilized as fingerprints to follow the hydrolysis of substrate (A) and to determine its purity and additionally yield. Furthermore, the acquired compound (B) was further purified by flash chromatography. Compound (B) was further characterized utilizing 1HNMR and mass spectrometry. Conclusion: An efficient chemoenzymatic procedure to optimize the preparation of peracetylated lactosamine B containing acetyl ester as extraordinary protecting group is presented. Compound B is a significant intermediate for the synthesis of pharmacologically active compound (e.g. complex oligosaccharides for biochemical, biophysical, or biological examinations). Besides, reaction monitoring utilizing HPLC proposes more exact information than spectroscopic methods.

3.
Adv Pharm Bull ; 6(2): 285-91, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27478794

RESUMO

PURPOSE: To determine the elements in Bryonia alba L. roots, collected from the Crimean Peninsula region in Ukraine. METHODS: Dry ashing was used as a flexible method and all elements were determined using atomic absorption spectrometry (AAS) equipped with flame and graphite furnace. RESULTS: The average concentrations of the determined elements, expressed as mg/100 g dry weight of the sample, were as follow: 13.000 for Fe, 78.000 for Si, 88.000 for P, 7.800 for Al, 0.130 for Mn, 105.000 for Mg, 0.030 for Pb, 0.052 for Ni, 0.030 for Mo, 210.000 for Ca, 0.130 for Cu, 5.200 for Zn, 13.000 for Na, 1170.000 for K, 0.780 for Sr, 0.030 for Co, 0.010 for Cd, 0.010 for As, and 0.010 for Hg. Toxic elements such as Cd and Pb were also found but at very low concentration. Among the analyzed elements, K was the most abundant followed by Ca, Mg, P, Si, Fe, Na, and Zn, whereas Hg, As, Cd, Co, Mo, and Pb were found in low concentration. CONCLUSION: The results suggest that the roots of Bryonia alba L. plant has potential medicinal property through their high element contents present. Moreover, it showed that the AAS method is a simple, fast, and reliable for the determination of elements in plant materials. The obtained results of the current study provide justification for the usage of such fruit in daily diet for nutrition and for medicinal usage in the treatment of various diseases.

4.
Adv Pharm Bull ; 5(2): 289-91, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26236670

RESUMO

PURPOSE: The present study is aimed to study the host-guest inclusion complexation of the naturally occurring cyclodextrins (CDs), namely; (α-CD,ß-CD, and γ-CD) with mitiglinide (MIT). METHODS: Host-guest inclusion complexation was simulated using semi-empirical PM3 method. RESULTS: The obtained results clearly indicate that the complexes formed are energetically favored in the presence of γ-CD (Ecomp = -17.884 kcal/mol) of the optimal configurations of (1:1) MIT/γ-CD inclusion complexes. Moreover, the results obtained reveal that the formation of more stable MIT/γ-CD complex compared to MIT/α-CD or MIT/ß-CD complexes is primarily due to differences in intermolecular hydrogen bonding. CONCLUSION: The present theoretical results may be informative to scientists who are devoting themselves to developing effective methods for enhancing the drug solubility.

5.
Adv Pharm Bull ; 5(4): 587-91, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26819933

RESUMO

PURPOSE: To separate and quantify four major saponins in the extracts of the skin and the endosperm of seeds of horse chestnut (Aesculus hippocastanum L.) using ultrasonic solvent extraction followed by a high performance liquid chromatography-diode array detector (HPLC-DAD) with positive confirmation by thin layer chromatography (TLC). METHODS: The saponins: escin Ia, escin Ib, isoescin Ia and isoescin Ib were extracted using ultrasonic extraction method. The optimized extraction conditions were: 70% methanol as extraction solvent, 80 °C as extraction temperature, and the extraction time was achieved in 4 hours. The HPLC conditions used: Zorbax SB-ODS-(150 mm × 2.1 mm, 3 µm) column, acetonitrile and 0.10% phosphoric acid solution (39:61 v/v) as mobile phase, flow rate was 0.5 mL min(-1) at 210 nm and 230 nm detection. The injection volume was 10 µL, and the separation was carried out isothermally at 30 °C in a heated chamber. RESULTS: The results indicated that the developed HPLC method is simple, sensitive and reliable. Moreover, the content of escins in seeds decreased by more than 30% in endosperm and by more than 40% in skin upon storage for two years. CONCLUSION: This assay can be readily utilized as a quality control method for horse chestnut and other related medicinal plants.

6.
Adv Pharm Bull ; 4(Suppl 2): 521-6, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25671184

RESUMO

PURPOSE: To investigate, for the first time, the chemical composition of essential oil of the tubers and leaves of Jerusalem artichoke (Helianthus tuberosus L.), a species of sunflower native to eastern North America, growing in Ukraine. METHODS: A hydrodistillation apparatus was used for the extraction of volatile components and then it was analysed by gas chromatography equipped with a split-splitless injector (split ratio, 1:50) and flame ionization detector (FID). The oil was analyzed under linear temperature programming applied at 4°C/min from 50°C - 340°C. Temperatures of the injector and FID detector were maintained at 280°C and 300°C, respectively. The chemical analysis of the oil was carried out using gas chromatography coupled to mass spectrometry (GC-MS), to determine the chemical composition of the volatile fraction. RESULTS: The essential oils content ranged from 0.00019 to 0.03486 and 0.00011 to 0.00205 (g/100g), in leaves and tubers, respectively. The qualitative and quantitative analysis led to the identification of 17 components in both species samples. The major component found in leaves and tubers was (-)-ß-bisabolene with 70.7% and 63.1%, respectively. CONCLUSION: Essential oil profile of Jerusalem artichoke species showed significant differences between leaves and tubers species. Additionally, the leaves of Jerusalem artichoke are a promising source of natural ß-bisabolene.

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