Pravin S. Wakte

Analgesic and anti-inflammatory activity of caryophyllene oxide from Annona squamosa L. bark.

Caryophyllene oxide was isolated from an unsaponified petroleum ether extract of the bark of Annona squamosa and studied for its analgesic and anti-inflammatory activity. Caryophyllene oxide at the doses of 12.5 and 25mg/kg body wt. and unsaponified petroleum ether extract at a dose of 50mg/kg body wt. showed significant central as well as peripheral analgesic, along with anti-inflammatory, activity. These activities of caryophyllene oxide were comparable with the standard drug used in the respective experiments.

Analgesic and anti-inflammatory activities of the sesquiterpene fraction from Annona reticulata L. bark.

The sesquiterpene fraction of Annona reticulata bark was studied by GC/MS. Three major components were identified: copaene (35.40%), patchoulane (13.49%) and 1H-cycloprop(e)azulene (22.77%). The fraction was also screened for its analgesic and anti-inflammatory activities. The sesquiterpene fraction at doses 12.5 and 25 mg kg−1 and the unsaponified petroleum ether extract at a dose of 50 mg kg−1 exhibited significant central as well as peripheral analgesic and anti-inflammatory activities. These activities were comparable with the standard drugs used in the respective experiments.

Analgesic and Antiinflammatory Activity of Kaur‐16‐en‐19‐oic acid from Annona reticulata L. Bark

Kaur‐16‐en‐19‐oic acid was isolated from the bark of Annona reticulata and studied for its analgesic and antiinflammatory activity. Analgesic activity was assessed using the hot plate test and acetic acid‐induced writhing, and the antiinflammatory activity using the carrageenan induced rat paw oedema method. Kaur‐16‐en‐19‐oic acid, at doses of 10 and 20 mg/kg, exhibited significant (p < 0.05) analgesic and antiinflammatory activity. These activities were comparable to the standard drugs used, and furthermore the analgesic effect of kaur‐16‐en‐19‐oic acid was blocked by naloxone (2 mg/kg) in both analgesic models. Copyright

Supercritical CO2 Assisted Extraction and LC–MS Identification of Picroside I and Picroside II from Picrorhiza kurroa

INTRODUCTION Picroside I and picroside II have been studied intensively because of their pharmacological actions and clinical applications. Numerous methods have been reported for extracting picroside I and picroside II from Picrorrhiza. kurroa rhizomes. This is the first report of picroside I and picroside II extraction using the supercritical carbon dioxide assisted extraction technique. OBJECTIVE To develop supercritical carbon dioxide assisted extraction and LC-MS identification of picroside I and picroside II from the Picrorrhiza kurroa Royle rhizomes. METHODOLOGY Surface response methodology based on 3³ fractional factorial design was used to extract picroside I and picroside II from P. kurroa rhizomes. The effects of various process factors, namely temperature (40-80°C), pressure (25-35 MPa) and co-solvent (methanol) concentration (0-10% v/v) on extraction yield of the two compounds were evaluated. The picroside I and picroside II contents were determined using validated LC-MS methodology. RESULTS The maximum yield of picroside I (32.502 ± 1.131 mg/g) and picroside II (9.717 ± 0.382 mg/g) was obtained at the 10% v/v co-solvent concentration, 40°C temperature and 30 MPa pressure. The conventional Soxhlet assisted methanol extract of P. kurroa powder resulted in 36.743 ± 1.75 and 11.251 ± 0.54 mg/g yield of picroside I and picroside II, respectively. CONCLUSION Variation of concentration and extraction time showed a significant effect on the picroside I and picroside II yield. Supercritical carbon dioxide assisted extraction using methanol as a co-solvent is an efficient and environmentally sustainable method for extracting picroside I and picroside II from P. kurroa rhizomes.

Development of floating chitosan-xanthan beads for oral controlled release of glipizide

Introduction: The aim of the present work was to develop controlled release, floating and mucoadhesive beads of glipizide by using the polyionic complexation technique. Plasma half-life of glipizide being 2–4 h was selected for development of controlled release dosage form. Methods: Formulation batches were designed by employing chitosan as cationic and xanthan gum as anionic polymers. In vitro drug release was evaluated for the period of 24 h in phosphate buffer pH 7.4. Results: Sustained release of drug was observed in all formulation batches with % drug release ranging from 87.50% to 100.67%, no significant effect on the drug release was observed after varying chitosan to xanthan gum ratio. Encapsulation efficiency was found to be in the range of 79.48 ± 1.10–94.48 ± 1.52. In vitro bioadhesion studies showed that beads had satisfactory bioadhesive strength ranging from 67.11% ± 1.73% to 93.12% ± 1.56%. Buoyancy studies revealed that beads possess comparable floating capacity in the gastric fluids. Swelling kinetics was carried in pH 1.2 and 7.4 buffers. Significant difference (P < 0.05) in swelling kinetics was observed. Drug to polymer interaction was analyzed by Fourier transform infrared spectroscopy and differential scanning calorimetry studies. Scanning electron microscopy studies revealed that formed beads were discrete with rough and wrinkled surfaces. Conclusions: In conclusion, beads were successfully formed by employing chitosan and xanthan gum and showed to possess sustained release effect. Beads also showed pH dependent swelling kinetics, this property can also be applied for the drugs which are susceptible to the acidic environment in the stomach, and comparable bioadhesive and floating properties were also observed.

Optimization of supercritical fluid extraction and HPLC identification of wedelolactone from Wedelia calendulacea by orthogonal array design.

The purpose of this work is to provide a complete study of the influence of operational parameters of the supercritical carbon dioxide assisted extraction (SC CO2E) on yield of wedelolactone from Wedelia calendulacea Less., and to find an optimal combination of factors that maximize the wedelolactone yield. In order to determine the optimal combination of the four factors viz. operating pressure, temperature, modifier concentration and extraction time, a Taguchi experimental design approach was used: four variables (three levels) in L9 orthogonal array. Wedelolactone content was determined using validated HPLC methodology. Optimum extraction conditions were found to be as follows: extraction pressure, 25 MPa; temperature, 40 °C; modifier concentration, 10% and extraction time, 90 min. Optimum extraction conditions demonstrated wedelolactone yield of 8.01 ± 0.34 mg/100 g W. calendulacea Less. Pressure, temperature and time showed significant (p < 0.05) effect on the wedelolactone yield. The supercritical carbon dioxide extraction showed higher selectivity than the conventional Soxhlet assisted extraction method.

Optimization of process variables for phyllanthin extraction from Phyllanthus amarus leaves by supercritical fluid using a Box-Behnken experimental design followed by HPLC identification.

The response surface methodology using the Box-Behnken design was established to describe supercritical carbon dioxide assisted extraction of phyllanthin from Phyllanthus amarus Schum and Thonn leaves prior to HPLC analysis. The effects of extraction pressure, temperature, modifier concentration and extraction time on the yield of phyllanthin were investigated. By solving the regression equation, the optimum conditions were as follows: extraction pressure 23.2 MPa, temperature 40 °C, methanol as modifier at a concentration of 10 % and time 90 min. Under these conditions, the phyllanthin yield was 12.83 ± 0.28 mg g-1, which was in good agreement with the predicted values. Modifier concentration and extraction time showed a significant effect on the phyllanthin yield.

Optimization of sample preparation variables for wedelolactone from Eclipta alba using Box-Behnken experimental design followed by HPLC identification

INTRODUCTION Coumestan wedelolactone is an important phytocomponent from Eclipta alba (L.) Hassk. It possesses diverse pharmacological activities, which have prompted the development of various extraction techniques and strategies for its better utilization. The aim of the present study is to develop and optimize supercritical carbon dioxide assisted sample preparation and HPLC identification of wedelolactone from E. alba (L.) Hassk. METHODS The response surface methodology was employed to study the optimization of sample preparation using supercritical carbon dioxide for wedelolactone from E. alba (L.) Hassk. The optimized sample preparation involves the investigation of quantitative effects of sample preparation parameters viz. operating pressure, temperature, modifier concentration and time on yield of wedelolactone using Box-Behnken design. The wedelolactone content was determined using validated HPLC methodology. The experimental data were fitted to second-order polynomial equation using multiple regression analysis and analyzed using the appropriate statistical method. RESULTS By solving the regression equation and analyzing 3D plots, the optimum extraction conditions were found to be: extraction pressure, 25 MPa; temperature, 56 °C; modifier concentration, 9.44% and extraction time, 60 min. Optimum extraction conditions demonstrated wedelolactone yield of 15.37 ± 0.63 mg/100 g E. alba (L.) Hassk, which was in good agreement with the predicted values. DISCUSSION AND CONCLUSION Temperature and modifier concentration showed significant effect on the wedelolactone yield. The supercritical carbon dioxide extraction showed higher selectivity than the conventional Soxhlet assisted extraction method.

Stability-indicating HPLC determination of pramipexole dihydrochloride in bulk drug and pharmaceutical dosage form

A novel stability-indicating high-performance liquid chromatographic assay method was developed and validated for quantitative determination of pramipexole dihydrochloride in bulk drugs and in pharmaceutical dosage form in the presence of degradation products. An isocratic, reversed phase HPLC method was developed to separate the drug from the degradation products, using an Ace5-C18 (250×4.6 mm, 5 µm) advance chromatography column, and 10 mmol L-1 ammonium acetate and acetonitrile (75:25 v/v) as a mobile phase. The detection was carried out at a wavelength of 260 nm. The pramipexole was subjected to stress conditions of hydrolysis (acid, base), oxidation, photolysis and thermal degradation. Degradation was observed for pramipexole in base, in acid and in 30% H2O2. The drug was found to be stable in the other stress conditions attempted. The degradation products were well resolved from the main peak. The percentage recovery of pramipexole was from (99.87 to 99.98%) in the pharmaceutical dosage form. The developed method was validated with respect to linearity, accuracy (recovery), precision, system suitability, specificity and robustness. The forced degradation studies prove the stability indicating power of the method.

SOLVENT FREE OXALIC ACID CATALYZED SYNTHESIS OF 1,5-BENZODIAZEPINES

In the present study 1, 5-benzodiazepines were synthesized from a range of α, β-unsaturated ketones and o-phenylendiamine using oxalic acid 10 mol% as a catalyst under solvent free conditions. The yields of the present method are better than the reported method which explains effectiveness of oxalic acid catalyst. The cost effective, resourceful, undemanding and environment friendly are the advantageous aspects of this method.