Uttam Singh Baghel

Construction and Validation of Binary Phase Diagram for Amorphous Solid Dispersion Using Flory–Huggins Theory

Drug–polymer miscibility is one of the fundamental prerequisite for the successful design and development of amorphous solid dispersion formulation. The purpose of the present work is to provide an example of the theoretical estimation of drug–polymer miscibility and solubility on the basis of Flory–Huggins (F–H) theory and experimental validation of the phase diagram. The F–H interaction parameter, χd-p, of model system, aceclofenac and Soluplus, was estimated by two methods: by melting point depression of drug in presence of different polymer fractions and by Hildebrand and Scott solubility parameter calculations. The simplified relationship between the F–H interaction parameter and temperature was established. This enabled us to generate free energy of mixing (ΔGmix) curves for varying drug–polymer compositions at different temperatures and finally the spinodal curve. The predicted behavior of the binary system was evaluated through X-ray diffraction, differential scanning calorimetry, and in vitro dissolution studies. The results suggest possibility of employing interaction parameter as preliminary tool for the estimation of drug–polymer miscibility.

In vitro cytotoxicity evaluation of stem bark and leaves of Anogeissus pendula: Lack of potent activity

Objective: Anogeissus pendula Edgew (Combretaceae) which is also known as “button tree” is one of the prominent species of Anogeissus genus which has several ethnomedicinal uses. Phytochemical investigation revealed the presence of alkaloids and phenolic compounds, such as flavonoids, lignins, tannins. So, pharmacological evaluation of this plant may lead to discovery of new activity. Therefore, the objective of the present study is to evaluate the in vitro cytotoxicity of stem bark and leaves hydroalcoholic extract of A. pendula. Materials and Methods: In vitro cytotoxicity was evaluated by MTT (3-(4,5-dimethyl thiazol-2-yl)-5-diphenyl tetrazolium bromide) assay against A431 (human epithelial carcinoma) and HepG-2 (human liver carcinoma) cell lines. The assay is based on the principle that the dead cells do not reduce the tetrazolium into formazan. Various concentrations (62.5-1000 μg/mL) of hydroalcoholic extracts were used and the concentration of test drug needed to inhibit cell growth by 50% (IC50) values is generated from the dose–response curves for each cell line. Microscopic examination was also carried out for morphological analysis of cells treated with extracts of A. pendula. Results: The hydroalcoholic extracts of stem bark and leaves revealed dose dependent, but insignificant activity against the cell lines i.e.A431 and HepG-2 as the IC50 was found to be greater than 1000 μg/mL for both the extracts against both the cell lines. There were no morphological changes in cells which supports the insignificant cytotoxicity. Conclusion: The results suggest that the hydroalcoholic extracts of stem bark and leaves of A. pendula have insignificant cytotoxicity.

Pharmacognostic standardization of the leaf of Melaleuca alternifolia (Maiden & Betche) Cheel

Background: Melaleuca alternifolia (Myrtaceae) is a well-known, commonly used, tall shrub plant in Ayurvedic medicine. Traditionally, it is used for its antimicrobial potential to treat cutaneous infections. No attempts have been made regarding pharmacognostic investigation of the plant till date. So, the present study was aimed to establish standards with the help of different pharmacognostic parameters. Methods: Various pharmacognostic parameters (morphological, microscopic, physicochemical evaluations and preliminary phytochemical screening) were studied along with fluorescent and thin layer chromatographic analysis of the extract. Result: Morphologically Melaleuca alternifolia is a shrub having height of 7 m with layered and papery bark. Leaves have an arranged pattern, petiole is 1 mm in length; linear-acute with dimensions of 10-35 mm x 1 mm. Organoleptic features shows that leaves have characteristic odour and astringent taste. The transverse section of the leaf reveals the existence of epidermal layers, mesophyll tissues, vascular bundles and secretory cavities. The stomata are anomocytic and leaf constants such as stomatal number is 180-200-225, stomatal index is 3.8-4.4-5.9, vein islet number is 18.68 (average), veinlet termination number 20.3 (average) and palisade ratio is 5.5-6.4-6.9. The results of phytochemical screening showed the occurrence of different phytoconstituents (flavonoids, phenolic tannins, phytosterol and terpenoids). Conclusion: The present study evaluated various pharmacognostic parameters which will help in quality control (standardization) of Melaleuca alternifolia leaves in crude form, in herbal formulation and also aid in the preparation of an herbal monograph for the species.