Diversity, phylogeny, and cytotoxic potential of Dictyopteris (Phaeophyceae) species along the Brazilian coast

• Grant number: 25/11357-4
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: October 01, 2025
• End date: May 31, 2029
• Field of knowledge: Biological Sciences - Biochemistry - Molecular Biology
• Principal Investigator: Mariana Cabral de Oliveira
• Grantee: Lara Habib Jankovski
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 22/03234-1 - Evolution and diversification of Phaeophyceae: exploring genomic data to understand the taxonomy, phylogeny and biogeography of brown algae, AP.PNGP.PI

Abstract

The genus Dictyopteris (Dictyotales, Phaeophyceae) is widely distributed across tropical and temperate seas. In Brazil, seven species have been reported, however, the systematics of this genus has been studied only through morphological techniques, and no molecular studies have been conducted on Brazilian species so far. Moreover, these macroalgae have high biotechnological potential, with several natural products such as steroids and sulfur-containing metabolites, which have shown promising pharmacological properties. Thus, the objective of this study is to investigate the diversity, distribution, genetic structure, and cytotoxic bioactivity of Dictyopteris species along the Brazilian coast, providing insights into their evolutionary patterns, biogeographic distribution, and bioactive potential. The study is divided into three main fronts: (1) taxonomy and phylogeny, where three individuals of each species per locality will be analyzed using five molecular markers and phylogenetic inferences; (2) phylogeographic analysis of D. delicatula, including assessments of genetic diversity, spatial structure, and population history; and (3) cytotoxic activity by the MTT (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide) in vitro assay from ethanolic extracts against colon, melanoma, and breast cancer cell lines. By combining molecular, morphological, and biochemical analyses, this research will contribute to more accurate species delimitation and distribution, revealing possible cryptic diversity, and exploring bioactive compounds with biotechnological potential.