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Schistosomiasis is a parasitic disease that affects more than 250 million people. The treatment is limited to praziquantel and the control of the intermediate host with the highly toxic molluscicidal niclosamide. Marine algae are a poorly explored and promising alternative that can provide lead compounds, and the use of multivariate analysis could contribute to quicker discovery. As part of our search for new natural compounds with which to control schistosomiasis, we screened 45 crude extracts obtained from 37 Brazilian seaweed species for their molluscicidal activity against Biomphalaria glabrata embryos and schistosomicidal activities against Schistosoma mansoni. Two sets of extracts were taxonomically grouped for metabolomic analysis. The extracts were analyzed by GC–MS, and the data were subjected to Pattern Hunter and Pearson correlation tests. Overall, 22 species (60%) showed activity in at least one of the two models. Multivariate analysis pointed towards 3 hits against B. glabrata veliger embryos in the Laurencia/Laurenciella set, 5 hits against B. glabrata blastula embryos, and 31 against S. mansoni in the Ochrophyta set. Preliminary annotations suggested some compounds such as triquinane alcohols, prenylated guaianes, dichotomanes, and xenianes. Despite the putative identification, this work presents potential candidates and can guide future isolation and identification.

Since the conception of the genus Laurencia by Lamouroux in 1813, several red macroalgal species have been included in it. In recent decades, the development of modern molecular tools has resulted in multiple taxonomic modifications, and presently, eight related genera are recognized in the so-called Laurencia complex. In the Macaronesian Region (Central East Atlantic Ocean), species from the Laurencia complex are keystone elements of the benthic communities, especially in the intertidal zone. In this review, we consolidate the existing knowledge about the Laurencia complex within the Macaronesian archipelagos and nearby areas. Morphological descriptions and phylogeographic remarks of the 16 currently accepted species--whose records were molecular or morphologically confirmed--are included together with an identification key for the Macaronesian Region. The phylogeographic data allowed us to re-visit the role of the Macaronesian archipelagos as a bridge area for the marine flora of the Mediterranean and Caribbean Seas (remnants of the former Thetyan Sea) or contemplate their marine flora as the result of successive processes of recolonization after the Quaternary glaciations from those donor areas. Finally, some comments about the frontiers of the research in the Laurencia complex in the Macaronesian Region and nearby coastal areas are included. [ABSTRACT FROM AUTHOR]

Abstract: Since the conception of the genus Laurencia by Lamouroux in 1813, several red macroalgal species have been included in it. In recent decades, the development of modern molecular tools has resulted in multiple taxonomic modifications, and presently, eight related genera are recognized in the so-called Laurencia complex. In the Macaronesian Region (Central East Atlantic Ocean), species from the Laurencia complex are keystone elements of the benthic communities, especially in the intertidal zone. In this review, we consolidate the existing knowledge about the Laurencia complex within the Macaronesian archipelagos and nearby areas. Morphological descriptions and phylogeographic remarks of the 16 currently accepted species—whose records were molecular or morphologically confirmed—are included together with an identification key for the Macaronesian Region. The phylogeographic data allowed us to re-visit the role of the Macaronesian archipelagos as a bridge area for the marine flora of the Mediterranean and Caribbean Seas (remnants of the former Thetyan Sea) or contemplate their marine flora as the result of successive processes of recolonization after the Quaternary glaciations from those donor areas. Finally, some comments about the frontiers of the research in the Laurencia complex in the Macaronesian Region and nearby coastal areas are included.

Within the Laurencia complex (Rhodophyta, Rhodomelaceae), six genera have been recognized based on both molecular analyses and morphology: Laurencia, Osmundea, Chondrophycus, Palisada, Yuzurua, and Laurenciella. Recently, new material from Australia has been collected and included in the current molecular phylogeny, resulting in a new clade. This study examined the generic delineations using a combination of morphological comparisons and phylogenetic analysis of chloroplast ( rbcL) nucleotide sequence. The molecular phylogeny recovered eight (rather than six) clades; Yuzurua, Laurenciella, Palisada, and Chondrophycus showed as monophyletic clades each with strong support. However, the genera Osmundea and Laurencia were polyphyletic. Consequently, the new genus Coronaphycus is proposed, resulting in the new combination Coronaphycus elatus and a description of the new species C. novus. [ABSTRACT FROM AUTHOR]

Schistosomiasis is a parasitic disease that affects more than 250 million people. The treatment is limited to praziquantel and the control of the intermediate host with the highly toxic molluscicidal niclosamide. Marine algae are a poorly explored and promising alternative that can provide lead compounds, and the use of multivariate analysis could contribute to quicker discovery. As part of our search for new natural compounds with which to control schistosomiasis, we screened 45 crude extracts obtained from 37 Brazilian seaweed species for their molluscicidal activity against Biomphalaria glabrata embryos and schistosomicidal activities against Schistosoma mansoni. Two sets of extracts were taxonomically grouped for metabolomic analysis. The extracts were analyzed by GC–MS, and the data were subjected to Pattern Hunter and Pearson correlation tests. Overall, 22 species (60%) showed activity in at least one of the two models. Multivariate analysis pointed towards 3 hits against B. glabrata veliger embryos in the Laurencia/Laurenciella set, 5 hits against B. glabrata blastula embryos, and 31 against S. mansoni in the Ochrophyta set. Preliminary annotations suggested some compounds such as triquinane alcohols, prenylated guaianes, dichotomanes, and xenianes. Despite the putative identification, this work presents potential candidates and can guide future isolation and identification. [ABSTRACT FROM AUTHOR]