Pharmacognostical and phytochemical standardization of the roots of Potentilla mooniana Wight

Background:Potentilla mooniana Wight. (PM) (Family: Rosaceae) is a plant commonly grown at the higher altitudes (1500–3660 meter) of the lower Asian continent and is traditionally used to treat gastric and mouth disorders. The present study was aimed to scientifically develop a standard monograph for PM on the basis of pharmacognostical and phytochemical aspects. Methods: Pharmacognostically the roots were analyzed following the standard parameters prescribed under WHO guidelines and Indian Herbal Pharmacopoeia. Results: Morphologically, the roots are cylindrical, dark brown and astringent to bitter in taste. Histologically, the root section showed the formation of secondary growth with wood formation and central lignified xylem vessels. Physicochemical standards quantified includes foreign organic matter (1.20% w/w), loss on drying (9.66% w/w), total ash (12.65% w/w), acid insoluble ash (4.65% w/w), water soluble ash (0.5% w/w), alcohol soluble extractive (21.3% w/w), water soluble extractive (14.6% w/w), foaming index (142.85), swelling index (6.5), haemolytic index (37.77). Quantification of pesticide residue content and heavy metals such as Pb, Cd, Zn and Hg was analyzed and were found to be present within the permissible limits. Powdered drug showed the presence of lignified xylem vessels with scalariform and spiral thickenings, tracheids, starch grains and fibres. Phytochemical screening showed the presence of phenolics, tannins, flavonoids, steroids, saponins, sugars, and amino acids. Quantification of phytoconstituents were also investigated such as phenolics (84.15mg/g tannic acid equivalent, TAE), tannins (65.31mg/g TAE), flavonoids (9.53mg/g rutin equivalent, RE), flavonols (2.01mg/g RE), saponins (20.75mg/g diosgenin equivalent, DE), sapogenins (15.4mg/g DE) and carbohydrates (56.8mg/g D–fructose equivalent). TLC of the root extract was also analyzed in the present study. Conclusion: In conclusion, the diagnostic characters obtained from the roots of P. mooniana will provide beneficial information in identifying and comparing this plant from other closely related Potentilla species.

Key words:Potentilla mooniana, Pharmacognosy, phytochemical, polyphenolics, heavy metal.