Studies on the bioactivity of Holothuria atra extracts collected from the South east coast of India

Many bioactive compounds have been extracted from various marine animals like tunicates, sponges, soft corals, echinoderms, sea hares, nudibranchs, bryozoans, sea slugs, etc. The aim of this study is to identify the methanolic extracts of Holothuria atra with various in vitro experiments such as antibacterial, larvicidal and immunomodulatory activities of H. atra commonly called lolly fish. Antibacterial activity was evaluated using the agar well diffusion method. The results showed that H. atra extracts were active against Klebsiella pneumoniae, Serratia liquefaciens, and Staphylococcus aureus. Specifically, H. atra inhibited the growth of Aedes aegypti. The LC50 value detected was 0.58%. Strong hemolytic activity of H. atra was identified. Similarly, significant immunostimulant activity was analyzed using NBT assay. Therefore it could be suggested that H. atra has the ability to induce biological activities due to the availability of bioactive compounds. These promising results have led this study to consider purification of the active compounds and for the development of drugs