The present study investigated antioxidant and antibacterial activities of 5 different extracts and derived fractions from the S. nepalense tubers. Identification of the most active fractions, their phytochemical characterization, total phenolic and flavonoid contents, and biological activities were also evaluated.Petroleum ether, chloroform, ethyl acetate, methanol, water extracts and methanol fractions were screened for their antibacterial activity at 10, 50 and 100 mg/mL doses against ten Gram-negative and Gram-positive bacterial strains by disc diffusion method. Their total antioxidant activity was measured by DPPH and ABTS assays. Identification of the main compounds was performed by LC-MS/MS. Methanol extract exhibited the highest antioxidant (IC 50 = 30.79 µg/mL and 24.53 µg/mL for DPPH and ABTS, respectively) and antibacterial (MIC 71.5 to >100 µg/mL) activities in comparison with the other extracts. Levels of phenolics and flavonoids were also the highest in the same extract, i.e. 19.2 mg GAE/g and 11.20 mg QE/g, respectively. Phytochemical investigation of the active fractions of the methanol extract led to the isolation of gallic acid (19.04 mg/g) and quercetin (23.4 mg/g). Therefore, methanol extract showed an interesting potential for both antioxidant and antibacterial activities, thus deserving attention for future applications in the fields of medicinal plants and food supplements.

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Inadequate skin permeability is the main challenge encountered in the transdermal drug delivery and to solve this crisis physical and chemical enhancement techniques are being developed. The aim of the present investigation was to study the combined effect of two such techniques, iontophoresis and esterification, on the transdermal delivery of atenolol. A series of ester prodrugs of atenolol were synthesized, characterized and studied for physicochemical properties and stability. In vitro permeation studies were carried out for atenolol and prodrugs at different donor concentrations (5, 10, and 20 mM) by passive process and iontophoresis (0.5 mA/cm(2)). Evaluation of the physicochemical parameters showed significant increase in lipophilicity and slight reduction in pK value in the ester prodrugs compared to parent drug. Stability studies revealed higher stability at pH 4 than pH 6. Prodrugs significantly enhanced the transdermal flux of atenolol in passive process while in iontophoresis the enhancement ranged from 1.4 to 2.7 fold compared to atenolol. In the prodrug series, permeation rate increased with increase in the length of alkyl side chain up to the addition of 5 carbon units, but thereafter no specific pattern was recorded in both passive and iontophoretic process. The steady state flux was highest in atenolol valerate (1.48 micromol/cm(2) h), which shows the promise of meeting the desired permeation rate (3.0- 31.0 micromol/ h) for maintenance of the therapeutic level in a 70 kg human.

Objective. The objective of this work encompasses the application of the response surface approach in the development of buccoadhesive pharmaceutical wafers of Loratadine (LOR). Methods. Experiments were performed according to a 32 factorial design to evaluate the effects of buccoadhesive polymer, sodium alginate (A), and lactose monohydrate as ingredient, of hydrophilic matrix former (B) on the bioadhesive force, disintegration time, percent (%) swelling index, and time taken for 70% drug release (t 70%). The effect of the two independent variables on the response variables was studied by response surface plots and contour plots generated by the Design-Expert software. The desirability function was used to optimize the response variables. Results. The compatibility between LOR and the wafer excipients was confirmed by differential scanning calorimetry, FTIR spectroscopy, and X-ray diffraction (XRD) analysis. Bioadhesion force, measured with TAXT2i texture analyzer, showed that the wafers had a good bioadhesive property which could be advantageous for retaining the drug into the buccal cavity. Conclusion. The observed responses taken were in agreement with the experimental values, and Loratadine wafers were produced with less experimental trials, and a patient compliant product was achieved with the concept of formulation by design.