Brazil has a megadiversity that includes marine species that are distributed along 800 km of shoreline. This biodiversity status holds promising biotechnological potential. Marine organisms are important sources of novel chemical species, with applications in the pharmaceutical, cosmetic, chemical, and nutraceutical fields. However, ecological pressures derived from anthropogenic actions, including the bioaccumulation of potentially toxic elements and microplastics, impact promising species. This review describes the current status of the biotechnological and environmental aspects of seaweeds and corals from the Brazilian coast, including publications from the last 5 years (from January 2018 to December 2022). The search was conducted in the main public databases (PubChem, PubMed, Science Direct, and Google Scholar) and in the Espacenet database (European Patent Office—EPO) and the Brazilian National Property Institute (INPI). Bioprospecting studies were reported for seventy-one seaweed species and fifteen corals, but few targeted the isolation of compounds. The antioxidant potential was the most investigated biological activity. Despite being potential sources of macro- and microelements, there is a literature gap regarding the presence of potentially toxic elements and other emergent contaminants, such as microplastics, in seaweeds and corals from the Brazilian coast.

Seaweeds have wide biotechnological applications. This study evaluated the chemical profile, photoprotective, and antioxidant potential of Padina sp., Caulerpa sertularioides , and Solieria filiformis collected in Bahia, Brazil. Chemical characterization by gas chromatography–mass spectrometry (GC–MS) and proton nuclear magnetic resonance ( ¹ H NMR) confirmed fucosterol in Padina sp., β‐sitosterol in C. sertularioides , and cholesterol in S. filiformis alongside fatty acids and aromatic metabolites; multivariate analyses supported species‐specific chemical patterns. The extracts exhibited ultraviolet (UV) absorption, in specific the UVA range, and were nonirritant in the Organization for Economic Co‐operation and Development (OECD) Test Guideline (TG) 491 assay. In human keratinocytes (HaCaT), C. sertularioides reduced UV‐induced reactive oxygen species (ROS) by 75%, whereas Padina sp. and S. filiformis achieved 42% reduction. Conversely, extracts exhibited photodegradation in the UV region and phototoxic potential in the OECD TG 432 (3T3 neutral red uptake, NRU) assay. Because these trials used complex crude extracts, future studies should optimize the extraction process, fractionate bioactive‐rich fractions, and isolate key compounds. These results highlight Brazilian algae as promising sources of new compounds and serve as a starting point for further investigations.