Pharmcognostical and Phytochemical Investigations on Stachytarpheta indica

Background: Stachytarpheta indica (Family: Verbenaceae), is a tropical plant useful to treat respiratory disorders, dropsy, rheumatic inflammation, intestinal worms and diarrhea. Pharmacological studies indicate antimicrobial, insecticidal and anthelmintic potential. Objectives: To establish quality control parameters, identify, isolate phytoconstituents and evaluate cytotoxic potential. Materials and Methods: S. indica was subjected to morphological, microscopical, phytochemical and cytotoxic studies. Flavonoid, scutellarin was identified by histochemical method and isolated; verbascoside was isolated, characterised by TLC of its hydrolytic products and UV spectroscopy. A new iridoid was isolated. Cytotoxicity of methanolic extract of S. indica was assessed on cancer cell lines (A549 for lung cancer, HT29 for colon cancer and MCF7 for breast cancer). Results: Transverse Section (TS) of the leaf include multiple collateral vascular bundles; stem TS features collenchymatous hypodermis and lignified fibres; while cork, phloem, and central wood represent root structure. Furthermore, a simple method for isolation of verbascoside from the plant would be beneficial as an alternative method for this important phenylpropanoid. Moreover, a new iridoid methyl 1-(4-ethoxybut-3-yn-1-yl)-4a-methyl- 1,4a,5,6,7,7a hexahydrocyclopenta [c] pyran-4-carboxylate was isolated from aqueous fraction and characterized. The preliminary in vitro screening results of cytotoxicity study on cell lines indicated that the methanolic extract exhibited non-significant cytotoxicity on human lung cancer (A549) cells, colon cancer (HT29) and breast cancer (MCF7) cells. Conclusion: Identification parameters developed in the study would be useful tool for its quality control and analysis. Simple method for identification and isolation of important compounds is easy to employ for future research.