Screening for antibacterial agents in three species of sea cucumbers from coastal areas of Sabah.  1. Three species of sea cucumbers found in the Sabah coastal areas were screened for the presence of antibacterial activity using three methods of extraction. Tests were conducted in vitro using the agar absorption method. 2. Both the lipid extract and the methanol-solvent extract from Holothuria atra, Holothuria scabra and Bohadshia argus were found to show no antibacterial activity. 3. Phosphate-buffered saline (PBS) from H. atra and B. argus, however, inhibited the growth of all gram-positive and gram-negative bacteria. 4. Comparisons were also made between extracts from the outer layer of H. atra and its inner part, and it was found that the extract from the outer layer showed less bacterial growth inhibition property. 5. The bacterial growth inhibition property of the PBS extract from H. atra, however, is dependent on the extract''s concentration. Bacterial growth inhibition was apparent after 48 hr incubation.