| Abstract [eng] |
Master’s thesis of D. Raginis “Comparison of the Manufacturing Technologies of Tablets and Capsules from Withania somnifera (L.) Root and Leaf Extract and the Evaluation of Antioxidant Properties”. Scientific supervisor assistant Dr. Rasa Kalėdaitė; Vilnius University, Faculty of Medicine, Institute of Biomedical Sciences (Center for Pharmacy and Pharmacology), Vilnius, 2026. Aim of the study: to formulate solid dosage forms containing Withania somnifera root and leaf extract, to compare the quality attributes of tablets and capsules, and to evaluate the antioxidant properties of the raw material. Objectives: 1. To determine the total phenolic content of Withania somnifera root and leaf extract using the Folin–Ciocalteu method and to evaluate its antioxidant activity using the DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging assay. 2. To evaluate the flow properties of granules prepared from Withania somnifera root and leaf extract by the wet granulation method, by calculating the Carr index and Hausner ratio, and to determine their particle size distribution. 3. To evaluate and compare the quality characteristics of prepared solid dosage forms (tablets and capsules), including mass uniformity, disintegration time and friability. Methods: total phenolic content in Withania somnifera root and leaf extracts was determined using the Folin–Ciocalteu method. Antioxidant activity was evaluated by DPPH radical scavenging assay. Flow properties of powders and granules were assessed using the Carr index and Hausner ratio. Granules were prepared by wet granulation and particle size distribution determined by sieving. Tablets were compressed using an eccentric press, and capsules filled semi-automatically. Quality of solid dosage forms was evaluated according to European Pharmacopoeia requirements (disintegration, mass uniformity, friability). Statistical analysis was performed using IBM SPSS, data processed in MS Excel. Results: antioxidant activity and total phenolic content of the extract were determined. The flow properties of powders and granules were evaluated using the Carr index and Hausner ratio, and particle size distribution was established. Two suitable batches of Withania somnifera tablets and capsules were formulated. The quality parameters of the solid pharmaceutical dosage forms, including mass uniformity, disintegration time and friability, were assessed. Research findings: 1. The total phenolic content of the Withania somnifera extract ranged from 6,11 ± 0,67 mg GAE/g to 9,40 ± 0,39 mg GAE/g when 40 % and 70 % ethanol were used as extraction solvents, respectively. The extract exhibited the highest antioxidant activity when 96 % ethanol was used, reaching 22,98 ± 1,41 mg TE/g. A statistically significant strong positive correlation was found between ethanol concentration and the antioxidant activity of the Withania somnifera extract. 2. Granules prepared by the wet granulation method using Withania somnifera extract and microcrystalline cellulose demonstrated better flow properties than the powder mixture. The Carr index values of both granule series were 11,22 ± 0,80 % and 13,21 ± 0,77 %, while the Hausner ratio values were 1,13 ± 0,01 and 1,15 ± 0,01, indicating good flowability. Particle size distribution analysis showed that the 0,355 – 0,5 mm fraction predominated in series 1, whereas the 0,710–1,0 mm fraction was dominant in series 2. A moderate, statistically significant positive correlation was established between granule diameter and particle size distribution. 3. Capsules prepared from Withania somnifera root and leaf extract and microcrystalline cellulose complied with all European Pharmacopoeia quality requirements, including mass uniformity and disintegration. In contrast, tablets met the requirements for mass uniformity and friability but failed to comply with the disintegration criterion. Therefore, capsule manufacturing technology can be considered technologically more suitable. |
