Analysis of Bioactive Compounds Present in the Leaf Extracts of Senna alata, Dennettia tripetalla and Delonix regia

ABSTRACT

Background and Objectives: Tropical shrubs have been in use as medicinal and ornamental plants by traditional herbalists in Southern Nigeria in the management and treatment of various illnesses. Materials and Methods: The Gas Chromatography-Mass Spectrometry (GC-MS) of the dichloromethane extracts of Senna alata, Dennettia tripetalla and Delonix regia leaves were carried out to analyze the bioactive compounds present in the leaves of these plants. Ten grams (10 g) of each of the powdered samples were extracted with 20 mls of dichloromethane, concentrated on a steam bath to about 5ml, purified by passing through a pasture pipette packed with silica gel and anhydrous sodium sulphate on a membrane and air-dried to about 2ml for gas chromatographic analysis. The dichloromethane concentrate of the various extracts was diluted with 98% hexane and 1μ/l of each diluted sample was automatically injected into the Gas chromatographic Model: 7890A (GC) interfaced with Mass Selective Detector model: 5975C (MSD). Identification of bioactive compounds present in the different extracts was based on GC retention time on HP- 5 column and matching of the spectra with computer software using the Chem-software attached to the MS library. Detection of compounds present in each leaf sample was confirmed using the database of the National Institute of Standards and Technology (NIST). Results: The results showed that the leaf extract of S. alata, had the highest peaks observed for Vitamin E (38.338%) and n-Hexadecanoic acid (21.695%), at retention times of 33.419 and 20 minutes respectively. D. regia leaf extract had the highest peaks observed for Dodecanoic acid, 1, 2, 3-propanetriyl ester (37.228%) and Phytol (34.681%) at retention times of 33.664 and 22.535 minutes respectively. Also, the results from D. tripetalla extracts showed that the highest peaks were observed for Supraene (27.91%) followed by 5, 9, 13-pentadecatriene-2-one/6, 10, 14-trimethyl/(E, E) (27.778%) at retention times of 30.897 and 19.441 minutes respectively. Conclusions: The analysis of the dichloromethane leaf extracts of the three plants showed that they contain bioactive compounds which can be explored for nutraceutical and medicinal uses.