Innovative microbiome-based system for the improvement of productivity, safety and sustainability of mussels farming

Northwestern Adriatic Sea Mediterranean mussels are exposed to fluctuating environmental parameters and to natural and anthropogenic stressors. Today is well known that mussels can be defined as holobiont, even if remains a lot to elucidate about how an organism and its microbial component response to environmental stress. This PhD dissertation aims to investigate microbiome possible adaptive patters exploiting the organism physiology response to stress, using the NGS sequencing method. The experimental approach consisted of two phases to first determine (i) the microbiome at a tissue scale level, (ii) the microbiome and physiological response to natural and anthropogenic stress environment and the chemical assessment of the microecosystem the Northwestern Adriatic Sea Mediterranean Mussel lives in. Results revealed firstly a robust microbiome well differentiated from seawater microecosystem, with compositional variations at the organ level. Thanks to those findings, digestive gland, the organ in which digestive and detoxification processes allow animal to tolerate and accumulate xenobiotics of natural and anthropogenic origin, was the selected tissue for the second phase of the project. The second phase of the project evaluated the putative physiological variations and the compositional changes in microbiome of digestive gland. I then manage to assess microbiome region trends across the north Adriatic, with each sampling site well differentiated from the others. Finally, a chemical method able to a powerful tool for the analytical detection of the major pollutants in mussels were validated. These first results may provide baseline information for future studies approaches of seasonal and region trends of microbiota profiles and physiological responses in terms of metabolism.