BACKGROUND AND OBJECTIVESOceans cover ۷۰% of the Earth's surface. In recent decades, research on chemicals derived from marine organisms with high bioactivity has made marine life a bountiful source of metabolites that are beneficial to human health and quality of life. The primary objective of this study was to assess the antimicrobial efficacy of aqueous extracts obtained from the sea urchin Echinometra mathaei, gonads. The target microorganisms for evaluation were Helicobacter pylori, which has faced difficulties in its treatment in recent years due to the increase in antibiotic resistance.MATERIALS AND METHODSThe sea urchins were taken from the Boushehr coastal region, during the year ۲۰۲۱. The gonads of sea urchins rinsed with tap water, and then separated for the purpose of extraction. The tissue was homogenized for ۵ min. Samples were shaken for ۲۴ h (۹۰ rpm) and centrifuged at ۱۲۰۰۰ rpm for ۱۲ min at ۴ °C. The supernatant was kept at ۴ °C, and the residue was centrifuged again. After centrifugation and freeze-drying, the supernatants were stored at −۷۰ °C until antibacterial testing. This study investigated the inhibition zone and minimum inhibitory concentration (MIC) values of sea urchins extract against H. pylori utilizing seven clinical isolates using an in vitro disc diffusion and agar dilution assay according to the CLSI standard.RESULTS AND DISCUSSIONFollowing a ۷۲-hour incubation period at a temperature of ۳۷°C and micaerophile atmosphere, The aqueous extracts (۸ mg/ml) of sea urchins do not inhibit the growth of H. pylori in vitro, no inhibition was seen. H. pylori was inhibited in an agar dilution assay with minimal inhibition concentration (MIC) ۱۰۰۰ μg/mL. This finding suggests that the compounds in of sea urchin gonads are effective in vitro against H. pylori.CONCLUSIONThis research demonstrated that E. mathaei, often known as the sea urchin, has the potential to provide new classes of antibiotics. The extract from sea urchins, which have been shown to suppress H. pylori growth, should be further studied to isolate, purify, and identify the chemical structure of the antibacterial chemicals for medical application.