Evaluation of toxicity and antioxidant activities of the crude leaf extracts of Cnidoscolus chayamansa

The crude ethanol extract (CcE) of the leaves of C. chayamansa was partitioned to obtain crude hexane (CcH), chloroform (CcC), and aqueous (CcA) extracts. The decoction (CcD) of C. chayamansa leaf sample was also prepared. The bioactivities of these extracts were tested using brine shrimp lethality test (BSLT) and various in vitro antioxidant assays (phosphomolybdenum method, DPPH radical scavenging assay, inhibition of linoleic acid peroxidation using Ferric Thiocyanate assay, and test for the total phenolic contents using Folin-Ciocalteu method). The CcD was the most toxic extract against Artemia salina with LC50 of 316.2 ppm. The CcD and CcA exhibited good antiradical activities (44.5% for CcD and 51.2% for CcA) which can be validated by their high total phenolic contents of 66.8 gallic acid equivalence (GAE) and 50.4 GAE, respectively. The extract CcC exhibited the highest total antioxidant activity (79.7 ppm ascorbic acid equivalents and 79.0 ppm butylated hydroxytoluene equivalents). The results can provide additional scientific confirmation for the traditional use of C. chayamansa as medicine or for being a nutritious vegetable and can guide the isolation and characterization of the bioactive components.