Comparative Study on Pharmacognostical, Phytochemical Investigations and Quantification of Vasicine Content in the Extracts of Adhatoda vasica Nees and Adhatoda beddomei CB Clarke

Background: Adhatoda, a perennial shrub of family Acanthaceae are well-known medicinal plant for the treatment and management of respiratory disorders such as asthma and bronchitis. Adhatoda vasica and Adhatoda beddomei are the species of Adhatoda, has been widely used in Indian system of medicine. Although, phytochemical and pharmacological investigations were reported on A. vasica, there has been comparative investigations on different Adhatoda species are lacking. Objective: The study was undertaken to compare the pharmacognostical and phytochemical parameters of two species of Adhatoda for rapid identification and authentication of the plants. Materials and Methods: Pharmacognostical features were studied by macroscopic, microscopic studies and physicochemical analysis such as determination of foreign matter, ash value, extractive value and loss on drying. Phytochemical investigations were analysed using phytochemical screening, bioactive content determination, HPTLC fingerprint analysis and estimation of vasicine content by HPLC analysis. Results: Microscopic study differentiated the pharmacognostical features between two species by demonstrating the anatomical characteristics. Powder microscopy of A. vasica revealed the presence of diacytic stomata, glandular and non-glandular trichomes whereas rod shaped crystals were seen only in A. beddomei. Qualitative and quantitative phytochemical investigations revealed the presence and estimation of various phytoconstituents in both the species. HPTLC fingerprint profiling evaluated the number of constituents present in the extracts and HPLC analysis revealed high content of vasicine in A. vasica extracts when compared to A. beddomei. Conclusion: The present study provides the useful information to differentiate the plant species and can serve as a diagnostic tool for the standardization and identification of adulterant in the crude drug market.