Preliminary investigation of leaves of Costus speciosus and Aporosa lindleyana for their biochemical composition.

Abstract

Sri Lanka is a tropical country, rich with vast diversity of medicinal plants which include endemic species with wide array of pharmacological properties and other health promoting benefits. Thenð€€ƒ .. is still strong potential for discovery of novel pharmacological active compouncfs and preparation of health promoting products from Sri Lankan flora via screening based on ethnobotanical information. As non­communicable diseases (NCDs) such as cancers, cardiovascular, diabetes mellitus etc. has emerged as major health risks in all the parts of the world despite of available treatment methods, strengthening of research on exploration of flora to find promising alternatives to cure and prevent the NCDs is timely important. With this intension, the study was aimed to investigate two potential medicinal plants, Costus speciosus (Sin; Thembu) and Aporosa lindleyana (Sin; Kebella, an endemic plant) which have been known to have health beneficial effects specifically on diabetes millitus, for their phytochemical and proximate analyses. There is a scarcity of studies onA.lindleyana whereas some studies are available on C. speciosus mainly on rhizomes. Fresh plant leaves were collected from North-Western province in Sri Lanka and species were authenticated by the help of local experts. To prepare methanolic extracts, maceration was done using methanol for air dried, crushed plant leaves. Excess solvent was evaporated under reduced pressure and dried using a rotary evaporator at 55 °c. The phytochemical screening for alkaloids, glycosides, saponins, phytosterols, diterpenes and flavonoids, was carried out following the standard procedure. All the extracts gave positive results for the above screening tests. The proximate analyses such as ash, moisture, crude protein, fat, crude fibre and carbohydrates were carried out using the methods described by Association of Official Analytical Chemists (AOAC, 2010), The proximate analysis showed that moisture, ash, crude fats, protein, crude fibre and carbohydrate were 2.30%, 13.22%, 2.85%,1.69%, 10.58% and 69.36% for the leaves of A.lindleyana and 1.84%, 15.35%, 3.34%, 2.04%, 15.37% and 62.06% for the leaves of C.speciosus respectively. Results of the present study revealed that both C.speciosus and A.lindleyana leaves are rich with important phytochemicals namely alkaloids, terpenoids, saponins, glycosides, and flavanoids, and that both plant leaves contain crude fat, fibre and proteins in significant amount.