Pharmacognostic and Phytochemical studies on Leptadenia reticulata (retz.) wight & arn. and Ichnocarpus frutescens r. br. for identification of distinguishing biomarkers

Leptadenia reticulata (Retz.) W&A. or Jivanti, an important rasayana drug of India, is often confused with another twiner Ichnocarpus frutescens R. Br., to which it shares a number of morphological characters and thus the latter plant is often used to adulterate the former drug. Micromorphological, pharmacognostic, phytochemical and HPTLC fingerprint variations were identified to locate biomarkers distinguishing these two plants which would help in the correct identification of the plant, as well as to detect adulteration. The study of stomata in fresh plants showed stomata to be anisocytic in Leptadenia reticulata and paracytic in Ichnocarpus frutescens. Microscopic studies of the powders of both plants showed cuboidal calcium oxalate crystals, sclereids and starch grains in the former plant which were absent from the latter. Trichomes were multicellular and uniseriate in L. reticulata, but unicellular in I. frutesens. Leptadenia contained five flavones and a single glycoflavone whereas two flavonols were located in Ichnocarpus. Phenolic acid content also varied in both plants. Only I. frutescens contained propelargonidin. The HPTLC fingerprints of both the plants showed enough variation for identification of adulteration.