Authentication of shankhpushpi by RAPD markers

Background: "Shankhpushp i " , an important indigenous drug of Ayurveda, an ancient system of Indian medicine, improves memory power and intellect. It is used in many Ayurvedic formulations, either singly or in combination with other herbs, meant for sleeplessness, epilepsy, hallucinations and anxiety. At least three different plant species viz., Clitoria ternatea, Convolvulus pluricaulis and Evolvulus alsinoides are used as the source of this drug in the different parts of the country. Because of increased demand and high price, shankhpushp i is often adulterated in the trade by other related species. Therefore, a reliable authentication method is needed to facilitate differentiation/ identification of the genuine material from its adulterants. The present study was aimed at developing RAPD-based markers for identification of C. pluricaulis, E. alsinoides and C. ternatea, and analyzing the market samples of the drug to ascertain their authenticity. Materials and Methods: Fresh samples of source plants of shankhpushp i were collected from Ghaziabad and Delhi. The market samples were procured from the crude-drug markets of different geographical regions of India. The amplified polymorphic D N A (RAPD) technique was employed for characterization of genuine and market samples. Twenty-five 11 -mer oligonucleotide primers were used to amplify the D N A isolated. Results: Out of 25 primers, only four (OPN-03, OPN-04 , O P N 0 5 and OPN-06) yielded amplification products that produced clear and reproducible bands, which were used to characterize the market samples. RAPD profile of some market samples did not match with the authentic samples, indicating that these samples were either adulterated or spur ious. Conclus ions: The RAPD markers developed in this study may provide guidance for the authentication of plant materials traded as shankhpushp i .