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.

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Among the many functions that a building material needs to have, its insulation functions stand out. This type of materials acts by decreasing the conduction of heat/sound in to the environment. In this context, bio-insulations have been receiving an increasing attention due to its performance and the use of sustainable/naturals insulation materials. This study was conducted to evaluate the thermal and acoustic performance of bio-based boards made from the biomass of Spirulina, bacterial poly-β-hydroxybutyrate (PHB), and glass wool. The boards were manufactured under heated compression in different proportions: 33.33% glass wool, 33.33% PHB, and 33.33% Spirulina biomass (Board A); 20% glass wool, 40% PHB, and 40% Spirulina (Board B); 40% glass wool, 40% PHB, and 20% Spirulina (Board C); and 40% glass wool, 20% PHB, and 40% Spirulina (Board D). Boards A and B showed lower thermal conductivity (0.09 W m-1 K-1) compared to traditional insulating materials, such as gypsum neat (0.44 W m-1 K-1) and Kaolin insulating firebrick (0.08–0.19 W m-1 K-1). Board D showed the highest sound absorption coefficient of ~1600 Hz compared to other bio-based insulators at the same frequency, such as polypropylene based non-woven fiber and tea-leaf-fiber with the same thickness. For the noise reduction coefficient, board B showed better results than concrete. Thus, boards A and B are suitable as thermal insulators, while boards B and D are suitable as sound insulators. For simultaneous application as a thermal and sound insulator, board B is the best choice among all boards.

Schistosomiasis has been controlled for more than 40 years with a single drug, praziquantel, and only one molluscicide, niclosamide, raising concern of the possibility of the emergence of resistant strains. However, the molecular targets for both agents are thus far unknown. Consequently, the search for lead compounds from natural sources has been encouraged due to their diverse structure and function. Our search for natural compounds with potential use in schistosomiasis control led to the identification of an algal species, Laurencia dendroidea, whose extracts demonstrated significant activity toward both Schistosoma mansoni parasites and their intermediate host snails Biomphalaria glabrata. In the present study, three seaweed-derived halogenated sesquiterpenes, (−)-elatol, rogiolol, and obtusol are proposed as potential lead compounds for the development of anthelminthic drugs for the treatment of and pesticides for the environmental control of schistosomiasis. The three compounds were screened for their antischistosomal and molluscicidal activities. The screening revealed that rogiolol exhibits significant activity toward the survival of adult worms, and that all three compounds showed activity against S. mansoni cercariae and B. glabrata embryos. Biomonitored fractioning of L. dendroidea extracts indicated elatol as the most active compound toward cercariae larvae and snail embryos.