Tito Monteiro da Cruz Lotufo

Structure Elucidation and Anticancer Activity of 7-Oxostaurosporine Derivatives from the Brazilian Endemic Tunicate Eudistoma vannamei

The present study reports the identification of two new staurosporine derivatives, 2-hydroxy-7-oxostaurosporine (1) and 3-hydroxy-7-oxostaurosporine (2), obtained from mid-polar fractions of an aqueous methanol extract of the tunicate Eudistoma vannamei, endemic to the northeast coast of Brazil. The mixture of 1 and 2 displayed IC50 values in the nM range and was up to 14 times more cytotoxic than staurosporine across a panel of tumor cell lines, as evaluated using the MTT assay.

Ascidians from Rocas Atoll, northeast Brazil

Rocas Atoll is the only one of its kind in the South Atlantic—and the first Brazilian marine biological reserve. This is the first report about the ascidians from Rocas. A total of 12 species were found, 5 of them not hitherto described: Ascidia viridina sp. nov., Didemnum rochai sp. nov., Leptoclinides crocotulus sp. nov., Polysyncraton maurizeliae sp. nov., and Trididemnum rocasensis sp. nov.). One Caribbean species, Didemnum halimedae, was also discovered in the region for the first time. Further, this is the first record of Didemnum digestum in the Atlantic. The results indicate a high degree of endemism in the ascidian fauna from Rocas Atoll, where didemnids are presently the most important members.

Carbonate Production by Benthic Communities on Shallow Coralgal Reefs of Abrolhos Bank, Brazil.

The abundance of reef builders, non-builders and the calcium carbonate produced by communities established in Calcification Accretion Units (CAUs) were determined in three Abrolhos Bank shallow reefs during the period from 2012 to 2014. In addition, the seawater temperature, the irradiance, and the amount and composition of the sediments were determined. The inner and outer reef arcs were compared. CAUs located on the inner reef shelf were under the influence of terrigenous sediments. On the outer reefs, the sediments were composed primarily of marine biogenic carbonates. The mean carbonate production in shallow reefs of Abrolhos was 579 ± 98 g m-2 y-1. The builder community was dominated by crustose coralline algae, while the non-builder community was dominated by turf. A marine heat wave was detected during the summer of 2013–2014, and the number of consecutive days with a temperature above or below the summer mean was positively correlated with the turf cover increase. The mean carbonate production of the shallow reefs of Abrolhos Bank was greater than the estimated carbonate production measured for artificial structures on several other shallow reefs of the world. The calcimass was higher than the non-calcareous mass, suggesting that the Abrolhos reefs are still in a positive carbonate production balance. Given that marine heat waves produce an increase of turf cover on the shallow reefs of the Abrolhos, a decrease in the cover represented by reef builders and shifting carbonate production are expected in the near future.

Prospecting anticancer compounds in actinomycetes recovered from the sediments of Saint Peter and Saint Paul's Archipelago, Brazil

Saint Peter and Saint Pauls Archipelago is a collection of 15 islets and rocks remotely located in the equatorial Atlantic Ocean. In this particular site, the present project intended to assess the biodiversity and biotechnological potential of bacteria from the actinomycete group. This study presents the first results of this assessment. From 21 sediment samples, 268 strains were isolated and codified as BRA followed by three numbers. Of those, 94 strains were grown in liquid media and submitted to chemical extractions with AcOEt (A), BuOH (B), and MeOH (M). A total of 224 extracts were screened for their cytotoxic activity and 41 were significantly active against HCT‐116 cancer cells. The obtained IC50 values ranged from 0.04 to 31.55 μg/ml. The HR‐LC/MS dereplication analysis of the active extracts showed the occurrence of several known anticancer compounds. Individual compounds, identified using HR‐MS combined with analysis of the AntiMarin database, included saliniketals A and B, piericidins A and C and glucopiericidin A, staurosporine, N‐methylstaurosporine, hydroxydimethyl‐staurosporine and N‐carbamoylstaurosporine, salinisporamycin A, and rifamycins S and B. BRA‐199, identified as Streptomyces sp., was submitted to bioassay‐guided fractionation, leading to isolation of the bioactive piericidins A and C, glucopiericidin, and three known diketopiperazines, cyclo(l‐Phe‐trans‐4‐OH‐l‐Pro), cyclo(l‐Phe‐l‐Pro), and cyclo(l‐Trp‐l‐Pro).

The effect of climate change on the distribution of a tropical zoanthid (Palythoa caribaeorum) and its ecological implications

Palythoa caribaeorum is a zoanthid often dominant in shallow rocky environments along the west coast of the Atlantic Ocean, from the tropics to the subtropics. This species has high environmental tolerance and is a good space competitor in reef environments. Considering current and future scenarios in the global climate regime, this study aimed to model and analyze the distribution of P. caribaeorum, generating maps of potential distribution for the present and the year 2100. The distribution was modeled using maximum entropy (Maxent) based on 327 occurrence sites retrieved from the literature. Calcite concentration, maximum chlorophyll-a concentration, salinity, pH, and temperature range yielded a model with the smallest Akaike information criterion (2649.8), and were used in the present and future distribution model. Data from the HadGEM2-ES climate model were used to generate the projections for the year 2100. The present distribution of P. caribaeorum shows that parts of the Brazilian coast, Caribbean Sea, and Florida are suitable regions for the species, as they are characterized by high salinity and pH and small temperature variation. An expansion of the species’ distribution was forecast northward under mild climate scenarios, while a decrease of suitable areas was forecast in the south. In the climate scenario with the most intense changes, P. caribaeorum would lose one-half of its suitable habitats, including the northernmost and southernmost areas of its distribution. The Caribbean Sea and northeastern Brazil, as well as other places under the influence of coastal upwellings, may serve as potential havens for this species.

Illegal trade of aquarium species through the Brazilian postal service in Ceará State

Brazil is one of the main suppliers of aquarium species globally, and Ceara state is a recognised trading centre for this activity. Despite Brazilian Postal Law forbidding the mailing of live or dead organisms, smugglers still use this service to transport aquarium species throughout the country. To assess this unlawful practice, the Brazilian Institute of the Environment and Renewable Natural Resources (IBAMA, Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renovaveis) and the Brazilian Post and Telegraph Co. (ECT, Empresa Brasileira de Correios e Telegrafos) conducted 57 confiscations involving domestic transportation only. The main origin and principal destination of the confiscated packages was south-eastern Brazil, especially Sao Paulo state, where package inspections must be intensified. Considering all groups of seized species, freshwater fish were by far the most represented organisms due to intense translocation of Betta splendens. Some of the confiscated marine fish, echinoderms and cnidarians are included in the Brazilian List of Threatened Species; thus, their exploitation is restricted or forbidden. In addition, only 18 of the seized species were native to Brazil, and just 12 of them occur naturally in Ceara state, which both raises concerns about potential bioinvasions and demands more control by the Brazilian authorities of smuggled species. Although some illegal traders were repeatedly caught mailing organisms, confiscations do seem to mitigate the illicit transportation of species to some extent.