A rapid and selective high-performance liquid chromatographic assay for simultaneous quantitative determination of a new antifilarial drug (UMF-058, I) and mebendazole (MBZ) is described. After a simple extraction from whole blood, both compounds were analysed using a C18 Nova Pak reversed-phase column and a mobile phase of methanol-0.05 M ammonium dihydrogenphosphate (50:50, v/v) adjusted to pH 4.0, with ultraviolet detection at 291 nm. The average recoveries of I and MBZ over a concentration range of 25-250 ng/ml were 92.0 +/- 7.7 and 84.4 +/- 4.4%, respectively. The minimum detectable concentrations in whole blood for I and MBZ were 7 and 6 ng/ml, respectively. This method was found to be suitable for pharmacokinetic studies.
A rapid and selective high-performance liquid chromatographic (HPLC) method for the simultaneous determination of the antifilarial drug UMF-078 (I) and its metabolites UMF-060 (II) and flubendazole (III) is described. After a simple extraction from whole blood, the compounds were determined by HPLC using a C18 Inertsil ODS-2 reversed-phase column with methanol-0.05M ammonium acetate (pH 4.0) as the mobile phase and ultraviolet detection at 291 nm. The average recoveries of I, II and III over the concentration range 20-500 ng ml-1 were 69.9 +/- 4.7, 85.6 +/- 4.4 and 85.1 +/- 6.0%, respectively. The minimum detectable concentrations in whole blood for I, II and III were 10, 7 and 7 ng ml-1, respectively. This method was found to be suitable for pharmacokinetic studies.
Urethral duplication (UD) is an uncommon malformation. Obstruction rarely occurs in hypospadiac UD. We describe two children with incomplete hypospadiac UD in association with posterior urethral valves, a combination not previously recognised. The embryonic significance of this anomaly is discussed. Keywords Urethral duplication. Hypospadias. Posterior urethral valve. Megalourethra
A new approach using a simple solid-phase extraction technique has been developed for the determination of pyronaridine (PND), an antimalarial drug, in human plasma. After extraction with C18 solid-phase sorbent, PND was analyzed using a reverse phase chromatographic method with fluorescence detection (at lambda(ex)=267 nm and lambda(em)=443 nm). The mean extraction recovery for PND was 95.2%. The coefficient of variation for intra-assay precision, inter-assay precision and accuracy was less than 10%. The quantification limit with fluorescence detection was 0.010 microg/mL plasma. The method described herein has several advantages over other published methods since it is easy to perform and rapid. It also permits reducing both, solvent use and sample preparation time. The method has been used successfully to assay plasma samples from clinical pharmacokinetic studies.
A simple, sensitive and specific reversed phase high performance liquid chromatographic (RP-HPLC) method with UV detection at 251 nm was developed for simultaneous quantitation of buparvaquone (BPQ), atenolol, propranolol, quinidine and verapamil. The method was applicable in rat in situ intestinal permeability study to assess intestinal permeability of BPQ, a promising lead compound for Leishmania donovani infections. The method was validated on a C-4 column with mobile phase comprising ammonium acetate buffer (0.02 M, pH 3.5) and acetonitrile in the ratio of 30:70 (v/v) at a flow rate of 1.0 ml/min. The retention times for atenolol, quinidine, propranolol, verapamil and BPQ were 4.30, 5.96, 6.55, 7.98 and 8.54 min, respectively. The calibration curves were linear (correlation coefficient > or =0.996) in the selected range of each analyte. The method is specific and sensitive with limit of quantitation of 15 microg/ml for atenolol, 0.8 microg/ml for quinidine, 5 microg/ml for propranolol, 10 microg/ml for verapamil and 200 ng/ml for BPQ. The validated method was found to be accurate and precise in the working calibration range. Stability studies were carried out at different storage conditions and all the analytes were found to be stable. This method is simple, reliable and can be routinely used for accurate permeability characterization.
A simple and sensitive RP-HPLC-UV method was developed and validated for simultaneous determination of atenolol and propranolol and subsequently applied to investigate the effect of dimethyl sulfoxide in rat in situ intestinal permeability studies. Atenolol (400 microm) and propranolol (100 microm) were perfused in the small intestine of anaesthetized (pentobarbitone sodium 60 mg/kg, i.p.) male Sprague-Dawley rats either in the presence (1, 3 and 5%) or in the absence of dimethyl sulfoxide. There was no significant alteration (p > 0.05) in the permeability of atenolol and propranolol, which indicated there was no effect of various concentrations of dimethyl sulfoxide (1-5%) on the membrane integrity of the rat intestinal tissues. The analytical method was validated on a C(4) column with a mobile phase comprising ammonium acetate buffer (pH 3.5, 0.02 m) and acetonitrile in the ratio of 30:70 (v/v) at a flow rate of 1.0 mL/min. The validated method was found to be accurate and precise and stability studies were carried out at different storage conditions and both analytes were found to be stable. These findings are applicable for determining the absorbability of water-insoluble drugs and new chemical entities for the purpose of classifying them in the biopharmaceutical classification system.
A simple, sensitive and specific reversed-phase high-performance liquid chromatographic method with UV detection at 251 nm was developed for quantitation of buparvaquone (BPQ) in human and rabbit plasma. The method utilizes 250 microL of plasma and sample preparation involves protein precipitation followed by solid-phase extraction. The method was validated on a C18 column with mobile phase consisting of ammonium acetate buffer (0.02 m, pH 3.0) and acetonitrile in the ratio of 18:82 (v/v) at a flow rate of 1.1 mL/min. The calibration curves were linear (correlation coefficient>or=0.998) in the selected range. The method is specific and sensitive with limit of quantitation of 50 ng/mL for BPQ. The validated method was found to be accurate and precise in the working calibration range. Stability studies were carried out at different storage conditions and BPQ was found to be stable. Partial validation studies were carried out using rabbit plasma and intra- and inter-day precision and accuracy were within 7%. This method is simple, reliable and can be routinely used for preclinical pharmacokinetic studies for BPQ.
There is limited pharmacokinetic data available for the combination artesunate + amodiaquine, which is used widely to treat uncomplicated malaria. This study examines the bioavailability and tolerability of a fixed (200 mg artesunate + 540 mg amodiaquine) and loose (200 mg + 612 mg) combination with a 2x2 cross-over design in 24 healthy volunteers.
Clitoria ternatea is known for its antimicrobial activity but the antifungal effects of leaf extract on growth and morphogenesis of Aspergillus niger have not been observed. The extract showed a favorable antifungal activity against A. niger with a minimum inhibition concentration 0.8 mg/mL and minimum fungicidal concentration 1.6 mg/mL, respectively. The leaf extract exhibited considerable antifungal activity against filamentous fungi in a dose-dependent manner with 0.4 mg/mL IC50 value on hyphal growth of A. niger. The main changes observed under scanning electron microscopy after C. ternatea extract treatment were loss of cytoplasm in fungal hyphae and the hyphal wall and its diameter became markedly thinner, distorted, and resulted in cell wall disruption. In addition, conidiophore alterations were also observed when A. niger was treated with C. ternatea leaf extract.
Following up a popular use of crude leaf preparations from Carica papaya for the treatment of dengue infections, a suspension of powdered Carica papaya leaves in palm oil has been investigated for its effect on thrombocyte counts in mice, administering by gavage 15 mg of powdered leaves per kg body weight to 5 mice. Equal numbers of animals received corresponding volumes of either palm oil alone or physiological saline solution. Thrombocyte counts before and at 1, 2, 4, 8, 10, 12, 24, 48 and 72 hours after dosing revealed significantly higher mean counts at 1, 2, 4, 8, 10 and 12 after dosing with the C. papaya leaf formulation as compared to the mean count at hour 0. There was only a non-significant rise of thrombocyte counts in the group having received saline solution, possibly the expression of a normal circadian rhythm in mice. The group having received palm oil only showed a protracted increase of platelet counts that was significant at hours 8 and 48 and obviously the result of a hitherto unknown stimulation of thrombocyte release. The results call for a dose-response investigation and for extending the studies to the isolation and identification of the C. papaya substances responsible for the release and/or production of thrombocytes.
This study examines the in vitro antioxidant activities of the methanol extract of Swietenia mahagoni seeds (SMCM seed extract). The extract was screened for possible antioxidant activities by free radical scavenging activity (DPPH), xanthine oxidase inhibition (XOI), hydrogen peroxide scavenging activity (HPSA) and ferric-reducing antioxidant power (FRAP) assays. The total phenolic and flavonoid contents were also determined. The extract exhibits antioxidant activity of 23.29% with an IC(50 )value of 2.3 mg/mL in the DPPH radical scavenging method, 47.2% in the XOI assay, 49.5% by the HPSA method, and 0.728 mmol/Fe(II)g in the FRAP method at the concentration tested. The amount of total phenolics and flavonoid contents was 70.83 mg gallic acid equivalent (GAE) and 2.5 +/- 0.15 mg of catechin equivalent per gram of dry extract, respectively. High Performance Thin Layer Chromatography (HPTLC) screening indicates the presence of phenolic compounds in the SMCM seed extract. The results indicate that the extract has both high free radical scavenging and xanthine oxidase inhibition activity. The antioxidant activity of SMCM seed extract is comparable with that of other Malaysian tropical fruits and herbal plants.
The present study was designed to evaluate the antibacterial activities of Swietenia mahagoni crude methanolic (SMCM) seed extract. The antimicrobial activity of the oily extract against Gram-positive, Gram-negative, yeast and fungus strains was evaluated based on the inhibition zone using disc diffusion assay, minimal inhibition concentration (MIC) and minimal bactericidal concentration (MBC) values. The crude extract was subjected to various phytochemicals analysis. The demonstrated qualitative phytochemical tests exhibited the presences of common phytocompounds including alkaloids, terpenoids, antraquinones, cardiac glycosides, saponins, and volatile oils as major active constituents. The SMCM seed extract had inhibitory effects on the growth of Candida albicans, Staphylococcus aureus, Pseudomonas aeroginosa, Streptococcus faecalis and Proteus mirabillase and illustrated MIC and MBC values ranging from 25 mg/ml to 50 mg/ml.
Studies on the antioxidant and antimicrobial activities of Mitragyna speciosa leaf extracts are lacking. In this study the antioxidant properties of water, methanolic and alkaloid M. speciosa leaf extracts were evaluated using the DPPH (2,2-diphenyl-1- picrylhydrazyl) radical scavenging method. The amount of total phenolics and flavanoid contents were also estimated. The DPPH IC(50) values of the aqueous, alkaloid and methanolic extracts were 213.4, 104.81 and 37.08 microg/mL, respectively. The total phenolic content of the aqueous, alkaloid and methanolic extracts were 66.0 mg, 88.4, 105.6 mg GAE/g, respectively, while the total flavanoid were 28.2, 20.0 and 91.1 mg CAE/g respectively. The antioxidant activities were correlated with the total phenolic content. This result suggests that the relatively high antioxidant activity of the methanolic extract compared to aqueous and alkaloid extract could be possibly be due to its high phenolic content. The aqueous, alkaloid and methanolic extracts were screened for antimicrobial activity. The extracts showed antimicrobial activity against Salmonella typhi and Bacillus subtilis. The minimum inhibitory concentrations (MICs) of extracts determined by the broth dilution method ranged from 3.12 to 6.25 mg/mL. The alkaloid extract was found to be most effective against all of the tested organisms.
In the present study, we investigate the effects of three different Mitragyna speciosa extracts, namely methanolic, aqueous and total alkaloid extracts, on glutathione transferase-specific activity in male Sprague Dawley rat liver cytosol in vitro and in vivo. In the in vitro study, the effect of Mitragyna speciosa extracts (0.01 to 750 microg/mL) against the specific activity of glutathione transferases was examined in rat liver cytosolic fraction from untreated rats. Our data show concentration dependent inhibition of cytosolic GSTs when Mitragyna speciosa extract was added into the reaction mixture. At the highest concentration used, the methanolic extract showed the highest GSTs specific activity inhibition (61%), followed by aqueous (50%) and total alkaloid extract (43%), respectively. In in vivo study, three different dosages; 50, 100 and 200 mg/kg for methanolic and aqueous extracts and 5, 10 and 20 mg/kg for total alkaloid extract were given orally for 14 days. An increase in GST specific activity was generally observed. However, only Mitragyna speciosa aqueous extract with a dosage of 100 mg/kg showed significant results: 129% compared to control.
Cinnomomum iners standardized leaves methanolic extract (CSLE) was subjected to analgesic, toxicity and phytochemical studies. The analgesic activity of CSLE was evaluated using formalin, hot plate and tail flick tests at doses of 100, 200 and 500 mg/kg. CSLE showed significant activity (P < 0.05) in the formalin model (late phase) on the rats at doses of 200 and 500 mg/kg. However, CSLE did not show activity in the hot plate and tail flick tests. The results obtained suggest that CSLE acts peripherally to relieve pain. For the toxicity study, CSLE was orally administered to the Swiss albino mice according to the Organization for Economic Co-Operation and Development (OECD) guideline 423. There was no lethality or toxic symptoms observed for all the tested doses throughout the 14-day period. Phytochemical screening of CSLE showed the presence of cardiac glycoside, flavonoid, polyphenol, saponin, sugar, tannin and terpenoid.
Ethanolic extract of Curcuma xanthorrhiza was used to evaluate the analgesic and toxicity effects in vivo. The extract was standardized using GC-MS, which showed that 1 mg of Curcuma xanthorrhiza ethanolic extract contains 0.1238 mg of xanthorrhizol. The analgesic activity was studied in rats using three different models, namely the hot plate test, tail flick test and formalin-induced pain test. The acute oral toxicity was examined by the oral administration of standardized Curcuma xanthorrhiza ethanolic extract in mice at doses ranging from 300-5,000 mg/kg and observation for 14 days. Standardized Curcuma xanthorrhiza ethanolic extract did not show significant analgesic effect in the hot plate and tail flick tests. However, in the formalin-induced pain test, Curcuma xanthorrhiza ethanolic extract significantly (P < 0.05) suppressed the paw licking time of rats in both early and late phases at doses 200 and 400 mg/kg of the extract, respectively. In the acute oral toxicity study, Curcuma xanthorrhiza ethanolic extract did not show any toxic effects in mice at 5 g/kg. These experimental results suggest that the standardized Curcuma xanthorrhiza ethanolic extract showed peripheral and central antinociceptive activity associated with neurogenic pain as well as a relative absence of toxic effects which could compromise the medicinal use of this plant in folk medicine.
Mitragyna speciosa Korth is a medicinal plant indigenous to Thailand and Malaysia and has been known for its narcotic and coca-like effects. Many studies have been performed on the antinociceptive effect of the plant extracts of Thai origin; however, limited studies have been reported till date on M. speciosa extracts of Malaysian origin. Various concentrations of alkaloid (5-20 mg/kg), methanolic (50-200 mg/kg), and aqueous (100-400 mg/kg) extracts of Malaysian M. speciosa leaves were prepared and orally administered to nine groups of rats. Morphine (5 mg/kg, s.c.) and aspirin (300 mg/kg, p.o.) were used as control. Antagonism of the antinociceptive activity was evaluated by pretreatment with naloxone at a dose of 2 mg/kg (i.p.). Results showed that oral administration of the alkaloid (20 mg/kg), methanolic (200 mg/kg), and aqueous (400 mg/kg) extracts significantly prolonged the latency of nociceptive response compared with control groups in both hot plate and tail flick tests (P < 0.05). Antinociceptive action of the alkaloid (20 mg/kg), methanolic (200 mg/kg), and aqueous (400 mg/kg) extracts was significantly blocked by naloxone. In conclusion, these results suggest the presence of antinociceptive effect in various extracts of Malaysian M. speciosa leaves. In addition, the antinociceptive effective doses vary depending on the type of solvents used for extraction.
The seeds of Swietenia mahagoni have been applied in folk medicine for the treatment of hypertension, diabetes, malaria, amoebiasis, cough, chest pain, and intestinal parasitism. Here we are the first to report on the toxicity of the Swietenia mahagoni crude methanolic (SMCM) seed extract.
A new solid phase extraction method for rapid high performance liquid chromatography-UV determination of mitragynine in plasma has been developed. Optimal separation was achieved with an isocratic mobile phase consisting of acetonitrile-ammonium acetate buffer, 50 mM at pH 5.0 (50:50, v/v). The method had limits of detection and quantification of 0.025 and 0.050 microg/mL, respectively. The method was accurate and precise for the quantitative analysis of mitragynine in human and rat plasma with within-day and between-day accuracies between 84.0 and 109.6%, and their precision values were between 1.7 and 16.8%. Additional advantages over known methods are related to the solid phase extraction technique for sample preparation which yields a clean chromatogram, a short total analysis time, requires a smaller amount of plasma samples and has good assay sensitivity for bioanalytical application. The method was successfully applied in pharmacokinetic and stability studies of mitragynine. In the present study, mitragynine was found to be fairly stable during storage and sample preparation. The present study showed for the first time the detailed pharmacokinetic profiles of mitragynine. Following intravenous administration, mitragynine demonstrated a biphasic elimination from plasma. Oral absorption of the drug was slow, prolonged and was incomplete, with a calculated absolute oral bioavailability value of 3.03%. The variations observed in previous pharmacokinetic studies after oral administration of mitragynine could be attributed to its poor bioavailability rather than to the differences in assay method, metabolic saturation or mitragynine dose.