BIOMARKER RESPONSES IN CORAL SYMBIONTS (CNIDARIA-ANHTOZOA) EXPOSED TO PAH AND OCEAN ACIDIFICATION SCENARIOS

• Grant number: 25/06488-2
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• Start date: September 01, 2025
• End date: February 28, 2026
• Field of knowledge: Physical Sciences and Mathematics - Oceanography - Biological Oceanography
• Principal Investigator: Augusto Cesar
• Grantee: Marina Cunha Passarelli
• Supervisor: Maria Laura Martin Diaz
• Host Institution: Instituto do Mar (IMar). Universidade Federal de São Paulo (UNIFESP). Campus Baixada Santista. Santos , SP, Brazil
• Institution abroad: Universidad de Cádiz, Puerto Real (UCA), Spain
• Associated to the scholarship: 23/05390-3 - ASSESSMENT THE EFFECTS FROM PHENANTHRENE CONTAMINATION IN CORALS EXPOSED TO OCEAN ACIDIFICATION, BP.PD

Abstract

Climate change and the increase in Carbon Dioxide (CO2) emissions have led to oceanacidification, which can cause severe impacts on marine ecosystems. At the same time,contamination by Polycyclic Aromatic Hydrocarbons (PAHs), resulting fromanthropogenic activities, represents an additional threat to marine biodiversity, especiallycoral reefs. One of the primary mechanisms of impact from both acidification and PAHexposure is oxidative stress. This process can damage cellular components, includinglipids, proteins, and DNA, leading to coral bleaching events that are primarilycharacterized by the loss of photosynthetic symbionts. This project aims to assess thesublethal effects on coral symbionts exposed to phenanthrene contamination and oceanacidification scenarios, with a particular focus on biomarker analysis. For that,biomarkers of oxidative stress will be evaluated, including antioxidant enzymes(glutathione S-transferase, glutathione reductase, and glutathione peroxidase), as well aseffect biomarkers such as lipid peroxidation, and DNA damage in the symbiontSymbiodinium sp. The analyses will be conducted at the University of Cádiz, Spain, underthe supervision of Professor Dr. María Laura Martín-Díaz. Results analyses will focusmainly on assessing the effects of contamination by phenanthrene and ocean acidificationon the symbionts associated with the tissues of Mussismilia hispida corals that are nottypically considered in ecotoxicological assays. Additionally, different variables will beinvestigated to address the following questions: 1) Can ocean acidification scenariosinduce effects on corals at physiological and biochemical levels? 2) Can phenanthreneconcentrations affect the symbionts even under natural pH conditions (without CO2addition)? And finally, 3) Will acidification exacerbate phenanthrene toxicity to coralssymbionts?. (AU)