Phytochemical investigation and structural elucidation on seed extracts of Datura Stramonium

Abstract

Datura Stramonium is found in the family Solanaceae and and it is available throughout the world. It grows like a weed  on loam soil in an Ethiopian context. It is used as a traditional medicine for toothache, skin diseases, and asthma in  southern Ethiopia, especially in the Halaba zone. However, there was no research conducted in the study area in this  regard. This study aims to isolate and purify alkaloids from Datura Stramonium seeds. Alkaloids are the biologically active substances in this species. Hence, in this study, alkaloid extraction methods were used. Substances besides  alkaloids were removed by exhaustive liquid-liquid extraction with diethyl and petroleum ether. The final chloroform  extract was tested for alkaloid by Dragendorff's spray reagent. It gave a positive result for alkaloids. The fractionation  was done using column chromatography. Chloroform, ethyl acetate, ethanol and methanol were used as eluents. It was done by increasing the polarity of solvents. A total of 26 fractions were obtained. The purity of each sample fraction was  checked by thin-layer chromatography (TLC). The fractions that showed the same color and the same Rf value were  mixed. The pure fractions with sufficient amounts were studied by 1H NMR, 13 C NMR and DEPT-135 for structural  elucidation. In this study, the structures of two compounds, DSA-15 and DSA-21, were identified using IR 1HNMR, 13C  NMR, and DEPT-135. Both of them are alkaloids. From this study, it was found out that both DSA-15 and DSA-21 are new  compounds.