Effect of ethanol extract of flowers of Vitex trifolia Linn. on CCL4 induced hepatic injury in rats.

Hepatoprotective activity of ethanolic extract of flowers of Vitex trifolia (Verbenaceae) was studied against CCl4 induced hepatic injury in albino rats. The plant extract (EVT) at the dose of 200 mg/kg, p.o. showed a remarkable hepatoprotective activity. CCl4 induced a significant rise in serum glutamate pyruvate transaminase (SGPT), serum glutamate oxaloacetate transaminase (SGOT), alkaline phosphatase (ALP), total bilirubin and gamma glutamate transpeptidase (GGTP). Treatment of rats with EVT significantly (P<0.001) altered serum biomarker enzyme levels to near normal against CCl4 treated rats. The activity of the extract was comparable to the standard drug, silymarin (100 mg/kg, p.o.). Histopathological observations also revealed that treatment with EVT protected the animals from CCl4 induced liver damage. The results indicate that the flowers of V. trifolia possess hepatoprotective activity on CCl4 induced hepatic injury in rats.

Studies on effect of piperine on oral bioavailability of ampicillin and norfloxacin.

Ampicillin and Norfloxacin are used to treat variety of bacterial infections. These two drugs have low oral bioavailability. Co-administration of Piperine (20 mg/kg), an alkaloid from Piper nigrum L. enhanced oral bioavailability of Ampicillin and Norfloxacin in animal model. This is reflected in various pharmacokinetic measurements like Cmax, Tmax, AUC and t(1/2) of the above antibiotics in animal model.

An improved HPLC method with the aid of a chemometric protocol: simultaneous analysis of amlodipine and atorvastatin in pharmaceutical formulations.

Statistical experimental design and Derringer's desirability function were applied to develop an improved RP-HPLC method for the simultaneous analysis of amlodipine and atorvastatin in pharmaceutical formulations. Four independent factors were considered: acetonitrile content in the mobile phase; buffer pH; buffer concentration; and flow rate. The preliminary screening step was carried out, according to a 2(4-1) fractional factorial design, to identify the significant factors affecting the analysis time response. Then central composite design was applied for a response surface study, in order to examine in depth the effects of the most important factors. Subsequently, Derringer's desirability function was employed to simultaneously optimize the six responses: retention factor of first peak; two resolutions; and three retention times, each having a different target. This procedure allowed deduction of two separate optimum conditions, intended for the analysis of quality control and plasma samples, within the experimental domain. The predicted optimum for the quality control samples was: methanol-acetonitrile-15 mM K(2)HPO(4) buffer (pH 5.33) (10:42.08:47.92, v/v/v) as the mobile phase and 1.12 mL/min as the flow rate. The method using this optimized condition showed higher sensitivity and shorter analysis time than the previously published reports. The optimized assay condition was validated according to International Conference on Harmonization guidelines.

Formulation development and in vitro and in vivo evaluation of membrane-moderated transdermal systems of ampicillin sodium in ethanol: pH 4.7 buffer solvent system.

The objective of the present study was to develop membrane-moderated transdermal systems of ampicillin sodium and to evaluate them with respect to various in vitro and in vivo parameters. The membrane-type transdermal systems were prepared using a drug with various antinucleant polymers-hydroxypropyl methylcellulose (HPMC), methylcellulose (MC), cellulose acetate phthalate, chitosan, sodium alginate (SA), and sodium carboxymethylcellulose-in an ethanol: pH 4.7 buffer volatile system by the solvent evaporation technique with HPMC as the rate-controlling membrane for all the systems. The swelling properties of the polymers were studied, and drug-polymer interaction studies were performed. The patches were subjected to various physicochemical studies, in vitro release studies, permeation studies, and skin irritation studies. The best patch among the formulations was selected for further in vivo studies. Compared to the other patches, SA exhibited the highest moisture content at 16%; a 21% moisture uptake was found with MC. The release and permeation of the drug from the SA patch was found to be the maximum. The in vivo study of the SA patch exhibited a peak plasma concentration C(max) of 126 microg/mL at T(max) 4 hours. Hence, it can be concluded that hydrophilic ampicillin sodium can be developed as a transdermal delivery system with SA that is an alternative to intravenous administration and has minimal adverse effects.

Preparation and evaluation of a new erythromycin derivative -- erythromycin taurate.

Erythromycin taurate, a new derivative of erythromycin, was prepared by reacting erythromycin base with tauric acid and its physico-chemical and biological properties were evaluated. The derivative has reasonably good solubility in organic solvents. The partition coefficient values in chloroform/water 1.17 and octanol/water 1.16 systems indicate its good distribution in various tissues in vivo. The in vitro antimicrobial potency of the derivative (833.33 microg mg(-1)) is higher than that of the existing derivatives such as erythromycin estolate, erythromycin stearate, erythromycin ethyl succinate, erythromycin gluceptate, erythromycin lactobionate. The antimicrobial spectrum is comparable to that of the parent compound. Our results indicate that erythromycin taurate has a high potential for possible clinical application and is more efficient against Escherichia coli and Klebsiella pneumoniae than the parent base.