Pharmaconostic and phytochemical investigations of Pseuderanthemum palatiterum (Nees) Radlk. ex Lindau leaves

Abstract

Introduction: Fresh leaves of Pseuderanthemum palatiferum (Nees) Radlk. ex Lindau are claimed to cure various diseases and have become a popular medicinal plant among Thai people. Products made from P. palatiferum leaves - including powder decoctions, herbal tea bags and capsules - have been developed and are available in markets in Thailand, but without quality control. Methods: Microscopic characteristics were observed under a light microscope. Physicochemical properties - including loss on drying, total ash, acid-insoluble ash, and water extractive values - were determined. Phytochemical screening for major groups of compounds was performed, and a thin-layer chromatographic (TLC) fingerprint of this plant was developed. Results: The microscopic characteristics showed the arrangement of palisade cells into two layers, and the presence of multicellular trichomes with a warty wall in the upper epidermis. Phytochemical screening revealed that P palatiferum leaf extract contains flavonoids, phenolic compounds, unsaturated lactone rings, and steroid nuclei. Flavonoids, phenol carboxylic acid and terpenoids were detected in TLC fingerprints of P palatiferum extract developed using blends of toluene: ethyl acetate: formic acid (5:4.5:0.5) and ethyl acetate: formic acid: water (90:2:2) as solvent systems. Conclusion: The results are useful for the establishment of a monograph on this plant which could be used for quality control of plant materials.