Diversity of Sargassum and of its microbiome on the coast of Brazil

• Grant number: 20/09406-3
• Support Opportunities: BIOTA-FAPESP Program - Regular Research Grants
• Duration: December 01, 2020 - November 30, 2023
• Field of knowledge: Biological Sciences - Botany
• Principal Investigator: Mariana Cabral de Oliveira
• Grantee: Mariana Cabral de Oliveira
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated scholarship(s): 22/06688-3 - Technical support for molecular and biochemical studies on Sargassum, BP.TT

Abstract

Sargassum is one of the most diverse genera of marine macroalgae, with 351 benthic and two pelagic species, the latter form the Sargasso Sea. Sargassum species are recognized for its significant ecological role and for the production of several bioactive compounds, but little is known about the microbiomes associated to these algae and their role in the synthesis of these compounds. Since 2011, "golden tides" events formed by dense floating masses of Sargassum have been observed across the Caribbean region, on the north coast of South America and West Africa. In coastal regions, these masses of algae have a major impact on the environment, public health and the local economy. In Brazil, floating Sargassum strandings have been documented in recent years (2013 - 2019) in Pará, Maranhão and in oceanic islands such as Fernando de Noronha. Benthic species of Sargassum are common along the Brazilian coast and are a structuring component of marine communities, which are threatened by environmental changes. About 13 benthic species of Sargassum have been reported in Brazil, but there are doubts about the actual occurrence and distribution of these species and nothing is known about the possible impact of the arrival of floating Sargassum on native species, including on its microbiome. In this project we will investigate: i. the diversity and occurrence of Sargassum species on the Brazilian coast using molecular markers and morphological analysis; ii. the microbiome associated with the local species and the floating masses of Sargassum; iii. the dynamics of these microbiomes during a stranding event; and iv. the biochemical aspects of floating Sargassum. In addition to clarifying aspects related to the impacts of the arrival of these algae on the composition and functioning of coastal ecosystems, the present proposal will generate data that can assist in the use of these algae and associated microbial community, transforming a phenomenon that today is seen as an environmental problem into an opportunity to develop solutions derived from the oceans (Blue Economy). (AU)