Sea urchins perform essential ecological functions in the marine environment. Over the past decades, the entire world has undergone rapid environmental changes and transformations. These changes have affected and caused severe stress to marine species including sea urchins, therefore, it is important to study the effects of environmental stressors on their physiology to save them from extinction. The aim of this study was to investigate the impact of acute and chronic stressors on phagocytic and lysozyme activity of sea urchins (Arbacia punctulate) in three different stress conditions that include increased temperature as a physical stressor, lipopolysaccharides (LPS) as a chemical stressor, and both increased temperature and LPS. The coelomocytes of Sea urchins contain phagocytic cells along with other immune cells that circulates freely in the body fluid of coeloms and build the immune system. Coelomic fluid also contain lysozyme, an antibacterial enzyme which helps to protect them from infections agents. We investigated phagocytic activity by using formalin killed- Bacillus megaterium and lysozyme activity (Micrococcus lysodeikticus as a substrate) of three different stressed group (as mentioned above) and compared them with control. We observed that chemical and physical stressors have a significant impact on phagocytic and lysozyme activity of Arbacia punctulate. Each experimental group responded differently with physical and chemical stressors (acute and chronic). Detailed information will be presented at the conference.
Keywords: Sea urchins, stress, temperature, lipopolysaccharides (LPS), lysozyme, phagocytosis