Pharmacognostic Standardization of Pulsatilla nigricans Stoerck

Pulsatilla nigricans Linn. (Ranunculaceae) has been traditionally used in the treatment of nervousness, restlessness, ovaritis, ovaralgia, pain associated with debility and due to acute inflammation, uterine affections, acute meningitis, and as taeniafuge, but no work has ever been carried out for standardizing this potential plant. The present investigation establishes histological characters, micrometric determinations and physicochemical parameters for P. nigricans. Transverse sections of stem of P. nigricans showed outermost layer consists of a single layer of tangentially elongated epidermal cells, narrow zone of sclerenchymatous cells, i.e., hypodermis followed by continuous mass of thin walled, parenchymatous cells, of cortex, collateral and closed vascular bundles, lie scattered in the ground tissue towards periphery than at the centre and followed by pith comprising parenchymatous cells with large intracellular spaces. The powdered aerial parts of P. nigricans showed presence of anomocytic stomata, unicellular covering trichomes, pericyclic fibres, lignified spiral vessels and clusters of calcium oxalate crystals. Foreign organic matter content of air dried aerial parts of P. nigricans was found to be 0.38%. Moisture content of air dried aerial parts of P. nigricans was found to be 17%. The total ash was about 15 times more than the acid insoluble ash in P. nigricans whereas water soluble ash was about 2 times less than total ash in P. nigricans. Water-soluble extractive value of P. nigricans was found to be about 18 and 2 times, respectively, in comparison to petroleum etherand ethanol-soluble extractive value. Petroleum ether extract showed seven spots using hexane : ethyl acetate (17 : 3) as the mobile phase whereas TLC of chloroform extract showed nine spots for P. nigricans using toluene: ethyl acetate: glacial acetic acid (85:15:1) as the mobile phase, employing 0.5% anisaldehyde as the visualizing agent. Phytochemical screening of P. nigricans showed presence of steroids, flavonoids, tannins, and carbohydrates.