Pharmacognostic Comparision of Wild and Cultivated Solanum melongena L., Different Plant Parts Used in Ayurveda

In Sri Lanka, the wild variety of Solanum melongena L. (Solanaceae) is locally named as Ela batu of which roots are one of the heavily used raw materials for several common Ayurvedic preparations and it leads to high demand. However, due to the scarcity of genuine raw materials in the market, roots of the wild variety of S.melongena were adulterated by roots or stem parts of Brinjal or a cultivated variety of S. melongena. This study was carried out to distinguish genuine raw material and adulterates using morphological, anatomical, physico-chemical and chemical features to develop pharmacognostic standards for raw material authentication. Ten samples of fresh plants were collected from three different locations. Commercially available raw materials (i.e. dried roots) was also sampled as ten samples from each three suppliers in the open market. Some anatomical and morphological features showed significant differences usable in identification of roots and stems. Thickness of cork layer and nature of the cortical zone differentiate roots of wild and cultivated types of S.melongena. Physico-chemical studies on water soluble and alcohol soluble extractives of roots and stems of both plants show significant variations in (water soluble extractive of roots 11.831%, stems 4.522%: alcohol soluble extractive of roots 3.198%, stems 1.813%). Turbidity test for alkaloids and froth test for saponins shows higher values for roots than stems of both plants. Further confirmation on TLC and HPLC analysis with a reference standard of Solasodine common in S.melongena stems and roots proved that the chemical composition of roots of wild type is highly diverse than that of adulterants.