The Presence of Biomarker Enzymes of Selected Scleractinian Corals of Palk Bay, Southeast Coast of India

Abstract

The health and existence of coral reefs are in danger by an increasing range of environmental and anthropogenic impacts. The causes of coral reef decline include worldwide climate change, shoreline development, habitat destruction, pollution, sedimentation and overexploitation. These disasters have contributed to an estimated loss of 27% of the reefs. If the current pressure continues unabated, the estimated loss of coral reef will be about 60% by the year 2030. Therefore, the present study was aimed to analyze the enzymes involved in stress induced by coral pathogen and its resistance. We focused on the enzymes involved in melanin synthesis pathway (phenoloxidase (PO) and peroxidases (POD)) and free radical scavenging enzymes (super oxide dismutase (SOD), catalase (CAT)) and glutathione peroxidase (Gpx) in selected scleractinian corals such asAcropora formosa, Echinopora lamellosa, Favia favus, Favites halicora, Poritessp., andAnacropora forbesi.Overall, PO activity of coral was significantly lower than that of zooxanthellae except forFavia favus.Coral colonies with lower PO and POD activities are prone to disease. Maximum antioxidant defensive enzymes were observed inFavia favusfollowed byEchinopora lamellose.It is concluded that assay of these enzymes can be used as biomarkers for identifying the susceptibility of corals towards coral bleaching induced by pathogen.