Bioactivity Screening of Some Medicinal Plants using The Brine Shrimp Toxicity and Antioxidant Tests

Abstract

Plants have undoubtedly become reliable sources of new bioactive compounds or even known compounds with new activities. In furthering the search for such compounds, some plants, known from ethnobotanical studies to be useful in the treatment of various diseases and ailments, were screened for bioactivity using the brine shrimp toxicity test and the antioxidant (radical scavenging) test. Altogether 26 plants were used 17 were screened for brine shrimp toxicity while 16 were screened for antioxidant activity. The 70% ethanol extract of each plant was used. In addition standard tests for the presence of secondary metabolites were carried out. The plants were all found to demonstrate varying levels of activity in the test systems. In the brine shrimp lethality test Citrus sinensis was most active (LC50=16.8 ug/ml.) while Vernonia amygdalina was the most potent in the sedative estimate (LCS<J=3.0ug/ml.). In the antioxidant screening Zingiber officinale showed the greatest potency. While brine shrimp lethality could be used as a general indication of biological activity, plants with significant sedative effect on brine shrimp are potentially CNS-active. Antioxidant (radical scavenging) activity has been linked to inflammation and neuro-degenerative disorders.