Pharmacognostic, Physicochemical and Preliminary Phytochemical Investigation of Trapa natans Linn. root

Abstract

Background: Water caltrop (Singara), a plant belonging to the Trapaceae or Lytraceae family is an essential medicinal herb used in Ayurvedic preparations. Due to its unique characteristics and therapeutic properties. It is one of the most widely consumed vegetables in Asian countries. Taiwan, China and areas of Southeast Asia are home to Singara. Objective: To study the pharmacognostic, physicochemical and preliminary phytochemical investigation of Trapa natans Linn. root to establish the salient diagnostic features. Methods: Macroscopical, microscopical, physicochemical evaluation, detection of inorganic constituents, fluorescence analysis, extractive value and phytochemical analysis were performed. Extraction was performed by using different solvent such as petroleum ether, chloroform, acetone, methanol and distill water. Results: Macroscopically roots were mostly 10–65 mm long and less than 1 mm in diameter, except for the first adventitious roots arising from the cotyledonary nodes, which were much longer and often descended into the substrate river bottom. Microscopically the stele of roots is typically tetrarch, but hexarchy and pentarchy occur in large roots and triarchy in some roots. Central metaxylem vessel elements with a discontinuity of mature xylem elements between protoxylem and metaxylem are common. The cortex of Trapa natans Linn. root is characterized by aerenchyma in its middle by schizogeny but it often has asymmetrically larger lacunae in the inner cortex. The result of physicochemical parameters such as foreign matter, loss on drying (moisture content), total ash, acid insoluble ash, water soluble ash, water soluble extractive value, alcohol soluble extractive value, foaming index were found to be 0.3%w/w, 2.04%w/w, 9.5%w/w, 3.5%w/w, 5.0%w/w, 10.2%w/w, 5.2%w/w, less than 100 respectively. Qualitative tests of inorganic elements confirmed the presence of calcium, sodium, potassium, iron, sulphate, phosphate and chloride. The result of fluorescence analysis showed that in visible light, the root powder exhibit various shades of green and brown fluorescence. Various shades of green, brown and black were found under UV light. Preliminary phytochemical investigation of various extracts using different solvents confirmed the presence alkaloids, amino acid, glycosides, flavonoids, carbohydrate, steroids, triterpenoid compound, tannins, phenolic compounds, mucilage and saponins respectively. Conclusion: The results of this study concluded that the presences of various phytoconstituents in Trapa natans Linn. root may be medicinally useful. Also the results can be helpful in setting some diagnostic indices for identification, authentication and preparation of the monograph of the plant.