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The utilization of microalgae and fungi on an industrial scale is a challenge for researchers. Based on the question “how fungi have contributed to microalgae research?,” we verified the scientific trends on microalgae-fungi consortia focused on biofuels production by searching for articles on the Web of Science and Scopus databases through the terms “microalgae*” or phytoplankton and “fung*.” We found 1,452 articles published between 1950 and 2020; since 2006, the publication numbers have increased rapidly. The articles were published in 12 languages, but most were written in English (96.3%). Among 72 countries, China (360 articles), USA (344), and Germany (155) led the publication rank. Among the 10 most-prolific authors, 8 were Chinese, like 5 of the most-productive institutions, whereas the National Cheng Kung University was on the top of the list. The sources that published the most on the subject were: Bioresource Technology (96), PLoS ONE (28), and Science of the Total Environment (26). The keyword analysis emphasized the magnitude of applications in microalgae-fungi consortia research. Confirming this research question, biofuels appeared as a research trend, especially biodiesel, biogas, and related terms like lipid, lipid accumulation, anaerobic digestion, and biogas upgrading. For 70 years, articles have been published, where China and the United States seem to dominate the research scenario, and biodiesel is the main biofuel derived from this consortium. However, microalgae-based biofuel biorefinery is still a bottleneck on an industrial scale. Recent environmental challenges, such as greenhouse gas mitigation, can be a promising field for that microalgae-fungi application.

Schistosomiasis control in endemic areas depends on several factors, including mass drug delivery programs and interrupting the transmission of disease by controlling the intermediate host snails in the freshwater ecosystem using molluscicides. However, the use of the gold standard molluscicide, i.e., niclosamide, has been considered problematic due to its high cost, toxicity for aquatic organisms, and the emergence of niclosamide-resistant snail populations. In this work, we report the in silico driven identification of novel naphthoquinone compounds with high molluscicidal activity against Biomphalaria glabrata. For this purpose, we developed statistically robust and validated shape-based and machine learning models using B. glabrata bioassay compounds data. Using these models, we prioritized fourteen naphthoquinone compounds for further in vivo testing against adult, newly-hatched, and embryo of B. glabrata snails. Among them, compounds 3, 5, 6, 7, and 12 were the best candidates, presenting moderate potency against adult snails (LC50: 28.98–102.24 μM) and high potency (LC50: 14.52–0.45 μM) against newly-hatched snails and embryos. To summarize, the in silico approach explored here allowed us to discover five new molluscicidal candidates for prospective field studies.

Schistosomiasis is a disease that affects tropical and subtropical areas and is considered the second most prevalent parasitic disease in the world. One of the ways of combating this disease is the use of molluscicidal agents to eliminate or reduce the population of intermediate host snails. Polyhexamethylene biguanide hydrochloride (PHMB) is a chemical biocide commonly used as a disinfectant and antiseptic in the food industry and very successfully for the disinfection of swimming pools. The US Environmental Protection Agency (USEPA) indicated the PHMB as low environmental risk. The present study aimed to evaluate the molluscicidal activity of the PHMB in freshwater snail (Biomphalaria glabrata), intermediate host of Schistosoma mansoni. The PHMB showed high toxicity against all stages of the snail B. glabrata: embryos, new-borns and adults. The LC50 estimated was 0.98 mg L−1; 1.43 mg L−1 and 1.49 mg L−1, respectively, after exposure of 144 h for embryos and 96 h for new-borns and adults. PHMB did not prevent the development of embryos within the egg mass, since at all concentrations evaluated 80% of the embryos managed to develop until the hypo-stage, which is the last stage of development before hatching. However, PHMB inhibited the hatching of embryos by 100% at all concentrations above 1.6 mg L−1. PHMB proved to be a promising substance in the fight against schistosomiasis by eliminating the intermediate host (B. glabrata). This was the first study that makes an experimental observation of the molluscicidal activity of PHMB.

Iron oxide nanoparticles (IONPs) have been applied in several sectors in the environmental field, such as aquatic nanoremediation, due to their unique superparamagnetic and nanospecific properties. However, the knowledge of chronic toxicity of IONPs on aquatic invertebrate remains limited. Thus, the present study aimed to analyze the chronic toxicity of gluconic acid-functionalized IONPs (GLA-IONPs) and their dissolved counterpart (FeCl3) to freshwater snail Biomphalaria glabrata. GLA-IONPs were synthesized and characterized by multiple techniques, and the snails were exposed to both Fe forms at environmentally relevant concentrations (1.0–15.6 mg L−1) for 28 days. The bioaccumulation, mortality rate, behavior impairments, morphological alterations, fecundity and fertility of snails were analyzed. Results showed that GLA-IONPs induced high iron bioaccumulation in the entire soft tissue portion. Chronic exposure to GLA-IONP increased the behavioral impairments of snails compared to iron ions and control groups. Both Fe forms reduced the fecundity, while the mortality and reduced fertility were observed only after the exposure to GLA-IONPs at 15.6 mg L−1. Overall results indicated the behavioral impairments and reproductive toxicity associated, possibly, to bioaccumulation of GLA-IONPs in the B. glabrata. These results can be useful for the development of eco-friendly nanotechnologies.

Considering that most animals in an aquatic ecosystem are invertebrates, concerns about the ecotoxicological impact of emerging pollutants, such as nanomaterials, in these populations are relevant, which can lead to loss of aquatic biodiversity. However, knowledge concerning the effects of iron-based nanoparticles (IONPs) at cell and tissue-levels on freshwater gastropods remains limited. Thus, the present study aimed to analyse the histopathological changes and inflammatory response in the freshwater snail Biomphalaria glabrata after chronic exposure to gluconic-acid functionalized IONPs (GLA-IONPs) in comparison with their dissolved counterpart (FeCl3). Snails were exposed to both iron forms (1.0, 2.5, 6.25, and 15.62 mg L-1) for 28 days, and the qualitative and quantitative histopathological assessment on hermaphrodite gonads was conducted, following by analysis of histopathological indices and inflammatory responses. Results showed that both iron forms (GLA-IONPs and FeCl3) induced several gonadal histopathologies in the snails, mainly atresic acini, vacuolization of pre-vitellogenic oocytes, and atresic oocytes in a concentration-dependent pattern. GLA-IONPs induced a more intense inflammatory response and high frequency of vacuolized vitellogenic oocytes in comparison with FeCl3. Environmentally relevant concentration (2.5 mg L-1) of GLA-IONPs and FeCl3 induced high gonadal histopathological indices, indicating their potential reproductive toxicity. The current study showed that the chronic exposure of snails to GLA-IONPs and their dissolved counterpart (FeCl3) induced several gonadal histopathological changes and inflammatory responses in B. glabrata, confirming their potential risk to aquatic biodiversity.

The emerging growth of nanotechnology has attracted great attention due to its application in the parasite and intermediate host control. However, the knowledge concerning the mechanism of action (MoA) and toxicity of nanomaterials (NMs) to snails remain unclear. In this context, the present study revised the historical use of snails as experimental models in nanotoxicological studies and summarized the MoA and toxicity of NMs in aquatic and land snails. The data concerning the bioaccumulation, reproductive and transgenerational toxicity, embryotoxicity, genotoxicity and potential molluscicidal activity of NMs were revised. Furthermore, the data about the experimental conditions, such as exposure time, concentrations, cell and tissue-specific responses, snail species and nanoparticle types are discussed. Revised data showed that the toxic effects of NMs were reported for 21 snail species with medical, veterinary and ecological importance. The NM toxicity to snails is dependent on the physical and chemical properties of NMs, as well as their environmental transformation and experimental design. The NM bioaccumulation on snails was related to several toxic effects, such as reactive oxygen species (ROS) production, oxidative stress, following by oxidative damage to DNA, lipids and proteins. The NM metabolism in snails remains unknown. Results showed the potential use of NMs in the snail control program. Also, significant research gaps and recommendations for future researches are indicated. The present study confirms that snails are suitable invertebrate model system to assess the nanotoxicity.

Silver nanoparticles (Ag NPs) have been applied in several commercial products due to their antimicrobial properties, while their molluscicide properties, mode of action and toxicity to snail species remain unclear. In this study, the comparative toxicity of polyvinylpyrrolidone (PVP)-functionalized Ag NPs and their dissolved counterpart (Ag ions) was analyzed during the early developmental stages of the freshwater snail Biomphalaria glabrata, intermediate host of Schistosoma mansoni. Ag NPs were synthesized and characterized by multiple techniques, and the snail embryotoxicity was analyzed in terms of mortality, hatching, developmental stages and morphological alterations, while the acute toxicity to newly-hatched snails was analyzed by mortality and behavioral impairments. Results showed that both Ag forms induced mortality, hatching delay and morphological alterations (especially hydropic abnormalities) in snail embryos in a concentration and exposure time dependent patterns. Ag NPs showed low embryotoxic effects and similar toxicity for newly-hatched snails when compared to their dissolved counterparts, indicating that the nanotoxicity was dependent of snail developmental stages. The knowledge about the Ag NP toxicity to different early development stages of B. glabrata contributes to its potential use as molluscicide and control of neglected tropical diseases, including schistosomiasis.

Neurocysticercosis is the most common parasitic infection of the nervous system and currently represents a serious public health issue in many regions of Latin America, Asia, and Africa. To date, praziquantel is one of the chosen drugs for the treatment of neurocysticercosis. Its mechanism of action is based on the inhibition of different biochemical pathways within the parasite which contribute to its death. Thus, the aim of this work was to analyze, for the first time, whether the nanoformulations of praziquantel would modify the energetic pathway of Taenia crassiceps cysticerci, after an intracranial inoculation in BALB/c mice. Praziquantel nanosuspensions were formulated with polyvinyl alcohol, poloxamer 188, and poloxamer 407, as stabilizers. These formulations exhibited particle size in a range of 74–285 nm and zeta potential values in a range of − 8.1/− 13.2 depending on the type of stabilizer. Physical stability study at both 4 ± 2 and 25 ± 2 °C indicated that praziquantel (PZQ) nanoparticles were stable in terms of solubility and particle size after 120-day storage. In vivo studies demonstrated that those nanosystems were able to produce significant modifications on the concentrations of oxaloacetate, citrate, pyruvate, alpha-ketoglutarate, malate, succinate, lactate, beta-hydroxybutyrate, fumarate, and propionate involved in the metabolism of Taenia crassiceps cysticerci. Therefore, these nanoformulations may be considered as a promising tool to deliver praziquantel to the brain for the effective management of neurocysticercosis. Fil: Silva, Luciana Damacena. Universidade Federal de Goiás; Brasil Fil: Lima, Nayana Ferreira. Universidade Federal de Goiás; Brasil Fil: Arrua, Eva Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Química Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario; Argentina Fil: Salomon, Claudio Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Química Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario; Argentina Fil: Vinaud, Marina Clare. Universidade Federal de Goiás; Brasil

Although iron oxide nanoparticles (IONPs) have been widely used in nanomedicine and nanoremediation, their ecotoxicological effects on aquatic organisms remain unclear. In this study, the melanomacrophage center (MMC) response and hepatic histopathologic biomarkers were investigated in female guppies, Poecilia reticulata, exposed to citrate-functionalized IONPs (γ-Fe2O3) at an environmentally relevant iron concentration (0.3 mg L−1) over 21 days. The animals were collected at the beginning of the experiment and after 3, 7, 14, and 21 days of exposure. Guppies exposed to IONPs showed increases in the number, area, and perimeter of MMC when compared with the unexposed ones, especially after 7 days of exposure. The results showed an increase in the frequency of histopathologic changes in fish after 7 days of exposure to IONPs, such micro- and macro-vesicular steatosis, melanomacrophage aggregates, exudate, and hemorrhagic foci. The acute (3 and 7 days) and long-term (14 and 21 days) exposure of P. reticulata to IONPs induced high histopathologic indexes associated with circulatory disorders and inflammatory responses. Results showed that the MMC response and histopathologic index are important biomarkers to indicate the environmental impact of IONPs, confirming that the guppy P. reticulata is a target of ecotoxicity of IONPs.

The aim of this work was to develop nanosuspensions of praziquantel (PZQ) and to evaluate their influence on the energetic metabolism of cysticerci inoculated in BALB/c mice. We analyzed metabolic alterations of glycolytic pathways and the tricarboxylic acid cycle in the parasite. The nanosuspensions were prepared by precipitation and polyvinyl alcohol (PVA), poloxamer 188 (P188) and poloxamer 407 (P407) were used as stabilizers. Nanosuspension prepared with PVA had a particle size of 100 nm, while P188- and P407-based nanosuspensions had particle sizes of 74 nm and 285 nm, respectively. The zeta potential was -8.1, -8.6, and -13.2 for the formulations stabilized with PVA, P188 and P407, respectively. Treatments of T. crassiceps cysticerci-infected mice resulted in an increase in glycolysis organic acids, and enhanced the partial reversion of the tricarboxylic acid cycle, the urea cycle and the production of ketonic bodies in the parasites when compared to the groups treated with conventional PZQ. These data suggest that PZQ nanosuspensions greatly modified the energetic metabolism of cysticerci in vivo. Moreover, the remarkable metabolic alterations produced by the stabilizers indicate that further studies on nanoformulations are required to find potentially suitable nanomedicines. Fil: Silva, Luciana Damacena. State University of Goias; Brasil Fil: Arrua, Eva Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Química Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario; Argentina Fil: Pereira, Dayanne Amaral. State University of Goias; Brasil Fil: Fraga, Carolina Miguel. Universidade Federal de Goiás; Brasil Fil: da Costa, Tatiane Luiza. Universidade Federal de Goiás; Brasil Fil: Hemphill, Andrew. University of Berne Länggass; Suiza Fil: Salomon, Claudio Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Química Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Departamento de Farmacia; Argentina Fil: Vinaud, Marina Clare. Universidade Federal de Goiás; Brasil

Frações da folha e casca de pequi (Caryocar brasiliensis), testadas como moluscicidas, combateram o hospedeiro intermedário da esquistossomose. O nicho ecológico desse molusco está associado a mananciais de água. Além disso foi verificada a ação fungiotóxica da fração acetato de etila (folha), que apresentou elevada atividade frente ao fungo Paracoccidioides brasiliensis. Utilizou-se o epitélio branquial de Poecilia vivípara (Cyprinodontiformes, Poeciliidae), para testar a toxicidade dessas frações para células animais. Análises quantitativas demonstraram redução da densidade numérica das células de cloro expostas às frações da folha e aumento das expostas à casca. A folha e a casca causaram a redução da área das células de cloro (CC) no filamento branquial. O perímetro das CC não sofreu alteração significativa perante tais frações. A fração aquosa da folha foi mais tóxica ao guaru. Frações da casca são menos prejudiciais, podendo ser empregadas no controle de populações celulares, pois se mostraram muito eficazesFractions of Caryocar brasiliensis leaf and bark, tested as molluscicidal, fought the intermediary host of schistosomiasis. The ecological niche of this mollusk is related to water sources. Besides this, a fungitoxic action of the ethyl-acetate fraction (leaf) was verified, exhibiting high activity towards Paracoccidioides brasiliensis. The gill epithelium of Poecilia vivipara (Cyprinodontiformes, Poeciliidae) was used to test the toxicity of these fractions to animal cells. Quantitative analyses demonstrated a decrease in the density of chloride cells exposed to the leaf fractions and an increase in those exposed to bark fractions. The leaf and bark fractions induced a decrease in the area of the chloride cells (CC) in the gill filament. The perimeter of the CC did not suffer significant changes in face of these fractions. The aqueous fraction of the leaf is more toxic to the guaru. Bark fractions are less debilitating, and can be employed in the control of cell populations, showing high efficacy at it

Fractions of Caryocar brasiliensis leaf and bark, tested as molluscicidal, fought the intermediary host of schistosomiasis. The ecological niche of this mollusk is related to water sources. Besides this, a fungitoxic action of the ethyl-acetate fraction (leaf) was verified, exhibiting high activity towards Paracoccidioides brasiliensis . The gill epithelium of Poecilia vivipara (Cyprinodontiformes, Poeciliidae) was used to test the toxicity of these fractions to animal cells. Quantitative analyses demonstrated a decrease in the density of chloride cells exposed to the leaf fractions and an increase in those exposed to bark fractions. The leaf and bark fractions induced a decrease in the area of the chloride cells (CC) in the gill filament. The perimeter of the CC did not suffer significant changes in face of these fractions. The aqueous fraction of the leaf is more toxic to the guaru. Bark fractions are less debilitating, and can be employed in the control of cell populations, showing high efficacy at it

Calcium is considered an essential element for the metabolism of aquatic snail Biomphalaria glabrata (Say, 1818), intermediate host of Schistosoma mansoni Sambon, 1907 in Brazil, and represents a limiting factor to its distribution and adaptation to the environment. This study investigated the effect of different concentrations of exogenous CaCO3 on the energetic metabolism of B. glabrata for better understanding the physiological interference of chemical elements dissolved in the environment with the physiology of this species. Sixty-day-old snails were distributed into six groups, five exposed to different concentrations of CaCO3 (20, 40, 60, 80 and 100 mg/L) and a control group. The exposure to CaCO3 was assessed over time, with analysis of 15 snails of each group in the following intervals: 1, 14, 21 or 30 days for hemolymph extraction. Concentrations of calcium and glucose in the hemolymph were determined by commercial kits, and organic acids were extracted using an ion exchange column and analyzed by high-performance liquid chromatography. Concentration of calcium in the hemolymph showed no significant difference (p>0.05) from the control group and between the concentrations tested. Concentration of glucose decreased (p0,05) em relação ao controle e nas concentrações testadas. A concentração de glicose diminuiu (p