The root bark of Calotropis procera (Family: Asclepiadaceae) was extracted with methanol. The methanolic extract was separated into hexane, chloroform, ethyl acetate, and water soluble fractions. The ethyl acetate fraction was subjected to bioassay-guided fractionation and final purification was achieved by column chromatography. The structure of the compound was elucidated by spectroscopic methods (ESI-MS, 1H and C NMR, COSY, HSQC, and HMBC) and the comparison of the data obtained with that reported in the literature. It was concluded that the compounds isolated was taxifolin 4’-O-β-D-glucopyranoside, a dihydroquercetin glycoside. The crude extracts of hexane, chloroform, ethylacetate, and water soluble fractions of methanol extract and the isolated compound were subjected to antioxidant activity using 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay and brine shrimp lethality bioassay. The result shows that the maximum inhibitions in the DPPH assays were isolated compound (51.7 %), methanol (80.7 %), and water (29.2 %) fractions while ascorbic acid standard was (84.4 %). However, the results for hexane, chloroform and ethyl acetate fractions in the DPPH assays were poor and hence discarded. The results for the in vitro cytotoxicity activity shows that ethyl acetate and hexane fractions showed significant cytotoxicity with LC50 value of 1.0±0.2 and 2.4 ±0.1 respectively.

Cassia singueana is used in ethnomedicine for the management of pain and other related ailments. This study aimed to investigate the phytochemical constituents of the plant's root bark linked to the therapeutics claims of its analgesic and anti-inflammatory activities. The plant material was obtained and identified, and its phytochemical fingerprint profile was established using GC-MS technique. The plant's root bark was dried and ground into powder. The powdered material was extracted using 70% ethanol to obtain the crude extract (CECs). Another portion of the material (200 g) was extracted sequentially using soxhlet apparatus to obtain hexane (HFCs), chloroform (CFCs) and methanol MECs) fractions, respectively. The acute toxicity test (2000 mg/kg) and preliminary analgesic and antiinflammatory activity (100 mg/kg, p.o.) of the extract and fractions were performed in mice using acetic acid-induced writhing and formalin respectively. The most active hexane fraction (HFCs) was subjected to HPLC analysis to investigate the active phytochemical constituents. They were then evaluated for analgesic and anti-inflammatory efficacy at 25, 100 and 400 mg/kg, p.o. using formalin (50 µl) induced pain in rats. Results showed that the root bark of C. singueana exhibited analgesic and antiinflammatory activity against the pain induced model. HPLC analysis revealed that the phytochemical constituents linked to these activities are gallic acid, caffeic acid, luteolin and ferulic acid.