Preliminary Phytochemical Evaluation, Isolation and Spectroscopic Characterization of Constituents in the Dried Extracts of the Whole Plant Crotalaria Biflora (L)

Pharmaceutical Science-Pharmacognosy for Efficient Natural Therapy

Abstract

Several drugs currently available today for a variety of ailments are developed directly or indirectly from plant source. With this view, the plant Crotalaria biflora was selected for our research and initially it was decided to evaluate the phytochemical compositions and their characterization by different spectral methods. The whole plant Crotalaria biflora was collected, authenticated, dried in shade and powdered by mechanical grinder. The powdered material was extracted individually with solvents viz., petroleum ether, chloroform, ethyl acetate and methanol in soxhlet apparatus. The dried extracts thus obtained were employed for the preliminary phytochemical evaluation for the presence of  alkaloids,  glycosides,  tannins,  flavonoids,  terpenoids,  sterols,  saponins etc.,  followed by  column  chromatography with  the  solvents  of ascending order of polarity from hexane to ethyl acetate in the ratio from 95:5 to 0:100 and thin-layer chromatography separation by eluted with different ratio of hexane:ethyl acetate like 90:10, 75:25, 50:50 and 25:75 and detected with vanillin in sulphuric acid. Based on the yield obtained in the chromatographic separation, the compounds selected were subjected to different spectroscopic evaluation such as FTIR, 13C NMR, 1H NMR and mass spectroscopic methods. In the preliminary phytochemical evaluation, significant positive results were obtained from the tests for alkaloids, terpenoids and sterols.  In column chromatography, 900 fractions were collected and each fraction was subjected to TLC separation and five pure compounds were isolated with the help of TLC. Based on the yield, two compounds were selected for spectral evaluation and the compound 1 was identified as (Z)-(6-hydroxy-1-methyl-5-oxo-1,2,5,6,7,8-hexahydroazocin-4-yl) methyl acetate and the compound 2 was identified as β-Sitosterol.  These results are useful for further investigation in the future particularly the biological activities of these extracts.