Marine Biotechnology: a sea of new resources and solutions for ocean and human health

The marine environment covers nearly the 70% of the earth surface. Furthermore, oceans contain a very rich and still unexplored biodiversity. Only the 10% of the total marine organisms living in the oceans are now identified and studied for various applications. Thus, the oceans represents one of most valuable natural resource. For this reason, the exploration of the marine ecosystem constitutes a European priority, within research strategies, in parallel with the creation of conservation and protection programs for keeping the ocean healthy for future generations, through an eco-friendly exploitation of marine resources. Starting from an ecological and holistic approach, all marine biodiversity will provide a sea of resources for biotechnological applications. In particular, marine organisms have several potential applications in the biotechnology field, for the discovery of new pharmaceuticals, nutraceuticals, cosmetics, food and feed, aquaculture methods and technologies, biomaterials, bioenergy, biomonitoring and bioremediation. In this experimental study, I addressed two aspects of the use of marine resources for biotechnological applications: a) the development of marine model organisms as useful molecular tool for in vitro eco-toxicological studies and for in situ assessment of ocean health; b) the discovery of new marine natural products from marine microalgae for biomedical applications. The sea urchin Paracentrotus lividus was studied as marine model organism in order to develop new tools to evaluate the effect of stressors in the marine environment. Using a bioinformatic approach, twelve genes involved in some of the main cell death pathways were identified from sea urchin P. lividus genome: Pl_Aifm1, Pl_Ripk, Pl_Tnfr16, Pl_Tnfr19/27, Pl_Bax, Pl_Bcl2, Pl_Parp, Pl_Becn, Pl_Pink, Pl_Ulk1/2 and Pl_Ulk3. Embryos treated with heptadienal, a bioactive compound from marine diatoms, activated programmed caspase-independent cell death (extrinsic apoptosis) with simultaneous involvement of selective autophagic mechanism (called mitophagy). These results are in accordance with molecular analysis obtained for human tumoral cell line treated with the same marine compound. In fact, A549 cells activated, after treatment with heptadienal, extrinsic apoptosis with the simultaneous trigger of autophagic pathway. The study of the potential of marine microalgae for biotechnological applications focused on antiproliferative and antioxidant activities. In detail, the microalga Alexandrium andersoni showed anticancer effect against two tumour cell lines; the crude extract of Tetraselmis suecica posseshowed a strong scavenging and repairing effect after oxidative damage. Results obtained demonstrated, from one hand, that the sea urchin P. lividus can represent a suitable model organism for the assessment of induction of cell death mechanisms by chemical extracts or pure compounds, but also as molecular tool for in situ studies of chemical contaminants or anthropogenic stressful factors that can interfere with the marine ecosystem. On the other hand, results obtained with two marine microalgae (A. andersoni and T. suecica) confirmed the enormous potential of marine microalgae for the identification of new natural products with possible applications for pharmaceutical and cosmeceutical industries.