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Dinizia Excelsa is an Amazonian tree with a wide range of applications as a raw material in the industry. The objective of this study was to extract, characterize, and evaluate the biological activities of xylan extracted from Dinizia excelsa wood. The xylan was obtained in five stages, including delignification, precipitation, purification, and freeze-drying. The physicochemical analysis of xylan included the determination of monosaccharides, elemental composition, FTIR analysis, 2D nuclear magnetic resonance spectroscopy, and the determination of molecular weight. Xylan had an extraction yield of 28.44% and an elemental composition of 35.03% carbon, 5.65% hydrogen, and 59.32% oxygen. FTIR analysis revealed similarities between Dinizia excelsa xylan and commercial xylan. 2D NMR analysis confirmed the presence of characteristic xylan groups. Furthermore, xylan has a low molecular weight. In vitro cytotoxicity tests demonstrated low toxicity, indicating its potential for biological applications. Immunomodulatory activity assays revealed that xylan stimulated cell proliferation and the production of anti-inflammatory cytokines. The anticoagulant activity of xylan was low compared to heparin. The antioxidant activity of xylan was weaker compared to ascorbic acid and butylated hydroxytoluene (BHT). These results indicate that xylan from Dinizia excelsa has potential for several biomedical applications due to its immunomodulatory and anticoagulant properties.

Currently, there is a demand for protein sources that do not use soil management or animal breeding. Among these sources we highlight the microorganisms, such cyanobacteria and microalgae, which have a simple growth using light, CO2, water and some mineral salts to generate high protein production. The extraction of these proteins depends on the method used. The most used methods for extracting bio-functional proteins are mechanical, chemical and enzymatic. The aim of this work is to analyze the protein extraction methods in microalgae using Scielo, ScienceDirect and NCBI (PubMed) electronic databases that made it possible to select original studies published in the last five years (2018-2023). A total of 2707 articles, 25 of which were selected for further analysis and subjected to risk of bias assessment. The genera Chlorella, Scenedesmus and Nannochloropsis were the most studied due to their high protein content. Mechanical methods and chemical hydrolysis are the most used methods, achieving an extraction yield of 46.0 % and 64.0 %, respectively. The best extraction results are obtained with a combination of methods, reaching up to 80.0 % yield. However, some aspects need to be observed to choose an ideal protein extraction method.

Olanzapine (OLZ) is an antipsychotic medication used to treat postpartum psychiatric symptoms. It aimed to evaluate the effects of administering OLZ to lactating rats on testicular parameters of adult Wistar rats. Mothers received 2.5, 5 or 10 mg/kg until weaning. Adult male rats showed decrease in body weight, weight of testes, epididymis, prostate, seminal gland and gonadosomatic index when higher doses of OLZ were administered. Testicular volumetric parameters, as well as the length of seminiferous tubules, were also reduced in animals treated with the highest doses of OLZ. The diameter of the seminiferous tubules and the height of the seminiferous epithelium were reduced. There was also a relevant decrease in the population of Sertoli cells and a relevant reduction in the volume of individual Leydig cells. Histopathological analysis of the testes showed lesions compatible with testicular degeneration in rats treated with the highest dose of OLZ. There was a significant reduction in plasma testosterone levels in all treatments. It is noted, therefore, that the adverse impact on the testes of the highest doses of the drug during the neonatal period persisted into adulthood, with the dose of 2.5 mg/kg of OLZ proving to be safer than the others.

In this work, an in silico study and evaluation of the cytotoxicity of 4-(4-chlorophenyl)thiazole compounds against mouse splenocytes and the chloroquine-sensitive Plasmodium falciparum 3D7 strain are reported. The in silico results showed that the compounds have important pharmacokinetic properties for compounds with potential drug candidates. Regarding cytotoxicity assays against splenocytes, the compounds have low cytotoxicity. In addition, they were able to promote activation of these cells by increasing nitric oxide production without promoting cell death. Finally, they were able to promote cell proliferation. Regarding the in vitro anti-P. falciparum activity assays, it was observed that the compounds were able to inhibit the parasite's growth, presenting IC50 values ​​ranging from 0.79 to greater than 10 µM. These results are promising when compared to chloroquine. Therefore, this study showed that 4-(4-chlorophenyl)thiazole compounds are promising candidates for antimalarials.

Morinda citrifolia, commonly known as noni, is a plant belonging to the Rubiaceae family. This plant has a high biological potential, which has different biological properties, including antioxidant, antibacterial, antiviral, antifungal, antitumor and anti-inflammatory. In this work, the immunomodulatory, antitumor and antimicrobial activities of lignin isolated from Morinda citrifolia leaves were investigated. The results showed that this lignin was not cytotoxic and that it was able to promote activation and differentiation of immune cells in addition to inducing the production of anti-inflammatory cytokines. Furthermore, it was able to inhibit the growth of different tumor and microbial cells in vitro. This pioneering study on these different activities shows that the lignin isolated in this study can be used as a raw material to obtain biomedical and pharmaceutical products.

Due to structural similarities and the possibility of connection between the two Aptian paleolakes in the Jatobá Basin and the Tucano Norte Sub-basin in North-eastern Brazil, the influence of the architecture of the crystalline basement under these lacustrine sedimentary rocks was analysed using gravimetric data near the faulted edges of the basins where the paleolakes are located. The Negra (Jatobá Basin) and Tonã (Tucano Norte Sub-basin) Hills are mainly sedimentary deposits of Aptian age and are linked to the post-rift I tectonic sequence. Aiming at the study of reservoirs analogous to pre-salt reservoirs, the gravimetric data were processed and interpreted to define the structural framework of the basin regions around these hills. Depth maps and density models were generated that could be analysed from various 3D perspectives, and the behaviour of the crystalline basement below these sedimentary sequences was investigated. In addition to the identification of horsts and semi-grabens that influenced the current relief pattern, the modelling showed that the Aptian paleolake sedimentary rocks of the Negra Hill are in the Ibimirim Low, which is approximately 2,900 m deep, while in the Tonã Hill, the sedimentary rocks are in the Salgado do Melão Low, which is approximately 5,100 m deep.

Antioxidants present in many fruit residues can play an essential role in the prevention of diseases. The aim of this study was to determine nutritional and mineral composition, fatty acids profile, anti-nutrients, bioactive compounds, antioxidant activity and technological properties of flour from residues generated by umbu fruit processing. Nutritional composition showed high levels of dietary fiber, especially insoluble fiber (56.67%). The flour can be classified as a good source of calcium, phosphorus and magnesium, and an excellent source of iron, zinc and copper. Palmitic and stearic saturated fatty acids and oleic and linoleic unsaturated fatty acids were identified. No potentially toxic substances were detected. Significant values of ascorbic acid (44.78 mg/100g), carotenoids (463.73 µg/100g) and flavonoids (37.85 mg QE/100g) were found, as well as very high levels of phenolic compounds (20357.26 mg GAE/100g). Strong antioxidant activity was detected in the flour by three methods (ABTS, DPPH and FRAP) demonstrating a linear positive correlation between phenolic content and antioxidant activity. The flour showed high absorption of water, oil, emulsifying capacity and emulsion stability presenting a great potential for use in foods, especially meat, bakery and dairy products. These results indicate promising prospects to full use of umbu as a functional ingredient.

Syzygium cumini L. Skeels belongs to Myrtaceae family. This species has been recognized by its antidiabetic, anti-inflammatory, and antimicrobial activities. Despite ever-increasing scientific interest for this species there is no pharmacopeia method for characterization and standardization of S. cumini yet. So, toward this aim, the objective of this work was to develop an efficient analytical methodology able to determine polyphenols and tannins content from leaves hydroethanolic extract of S. cumini using Folin-Ciocalteu method by ultraviolet absorption spectrophotometry (UV-Vis). The analytical methodology was developed for the first time in the literature for leaves of this specie shown to be fast and low-cost with results expressed through tannic acid equivalent (TAE). Moreover, the methodology presented selectivity with maximum absorption at 706 nm wavelength, linearity with R2>0.99; limit of detection 0.275 µg TAE mL-1 and 0.102 µg TAE mL-1; limit of quantification 1.046 µg TAE mL-1 and 0.912 µg TAE mL-1 for total polyphenols and total tannins, respectively. Furthermore, the methodology was accurate with recover value greater than 98%, as well as exact, reproductive, and robust with coefficient of variation values less than 15% for both compounds. All the results are found within the fixed limits according to RDC 166/2017.

The present study consisted in optimizing the extractive method of polyphenols and total tannins of leaves of Syzygium cumini (L) Skeels assisted by microwaves to potentiate the antimicrobial activity of the dried extract of S. cumini against sensitive and resistant strains. A Box-Behnken design that consisted of 27 experimental runs coupled with a desirability function for multiple response optimization was employed to optimize the total polyphenols content and total tannins content. Antimicrobial sensitivity tests were evaluated by obtaining the minimum inhibitory concentration, minimum fungicidal concentration and minimum bactericidal concentration in 96-well petri dishes. The optimal extraction conditions were found to be 8 min of extraction, under 300 w of microwave power, using a 1:34 g/mL solid/solvent ratio and 38% of ethanol concentration as extraction solvent. The parameter with the greatest influence in the extraction was primarily the time, followed by the potency and proportion solid/solvent. This yielded a total polyphenol content of 87.37 ± 1.85 mg TAE g-1ext and a total tannin content of 79.68 ± 1.64 mg TAE g-1 ext. All tested microorganisms were sensitive to the extract, evidencing the effectiveness of the extraction method optimization.

Human populations maintain diverse relationships with wild animals that lead to both positive and negative interactions. The aim of the present study was to investigate the ecology, interactions and human perceptions of Cerdocyon thous in rural landscapes in the state of Pernambuco in northeastern Brazil. Interviews were held from November to December 2015. Data collection involved the use of a semi-structured questionnaire and photographs of the fox. Most interviewees (96.94%) demonstrated knowledge of the species, attributing eight different vernacular denominations to the animal. The interviewees also demonstrated knowledge regarding its habitats, active hours, diet, behavior and diseases. The respondents pointed out negative aspects, such as the transmission of diseases (48.72%), the death of domesticated animals and consequent negative economic impact (42.74%), attacks against humans and other animals (6.84%) and causing an environment imbalance (1.70%). The positive roles attributed to the fox regarded its use as a resource for medicinal purposes, craftwork, mystical-religious ceremonies and as a pet. There is a need for further information on C. thous and adequate protection measures should be taken in local communities to ensure the conservation of the species in rural landscapes.

Oceanographic features influence the early stages of fish to a high degree. We investigated the influence of continental shelf-slope gradient on the ichthyoplankton composition and distribution off Northeastern Brazil. Two oceanographic campaigns were performed during July-August 2010 and 2012. The samplings were performed along three transects composed by three stations, covering the continental shelf and slope areas. Abiotic data were obtained by an ADCP and a CTD. The ichthyoplankton was sampled through diurnal and nocturnal hauls using a 500-µm bongo net from 200 m to the surface. A total of 1634 larvae and 4023 eggs, representing 91 genera and 76 species, were collected. Higher concentrations of fish eggs were found on the continental shelf, probably because of the North Brazil Undercurrent flux. Higher concentrations of larvae were found at night and could be associated with net avoidance or natural variation. Neritic, oceanic and transition groups of species association were determined. Larvae of neritic, demersal and pelagic fishes prevailed on the continental shelf, while larvae of oceanic, mesopelagic and bathypelagic fishes on the continental slope. Melanostomiidae, Scorpaena sp., Lestidium atlanticum, Lampadena sp. and Diaphus sp. were identified as indicators of the continental slope.

Fossil vertebrates from Antarctica are considerably rare, hampering our understanding of the evolutionary history of the biota from that continent. For several austral summers, the PALEOANTAR project has been carrying out fieldwork in the Antarctic Peninsula in search for fossils, particularly Cretaceous vertebrates. Among the specimens recovered so far are two bones referable to Pterosauria, more specifically to the Pterodacyloidea, the first volant reptiles from Antarctica to be fully described. MN 7800-V (part and counterpart) was recovered from a moraine at the Abernathy Flats (Santa Marta Formation, Lachman Crags Member, Santonian-Campanian) on James Ross Island. It is interpreted as the distal articulation of a first phalanx of the wing finger, representing an animal with an estimated wingspan between 3 and 4 m. The second specimen (MN 7801-V) comes from Vega Island (Snow Hill Island Formation, Maastrichtian) and is identified as a wing metacarpal IV of an animal with an estimated wingspan from 4 to 5 m. These occurrences show that pterodactyloids inhabited the Antarctic Peninsula at least during the Upper Cretaceous and demonstrate that large pterosaurs were widespread through all parts of the planet during that period.

One of the most serious problems in areas indicated for irrigation projects in the Brazilian Northeast region is the occurrence of sandy soils, known to have low moisture retention, but occurring in strategic locations in terms of water supply and geographical situation, and which can be used for agricultural purposes. The objective of this study was to evaluate the influence of particle size distribution and porosity on the water retention capacity of sandy soils in the semiarid area of the Northeast region. Soil bulk and particle densities, total porosity (macro, meso and microporosity), field capacity, permanent wilting point and soil-water retention curve were determined in samples of surface (A) and subsurface (C or Bw) horizons of ten sandy soil profiles. Particle size was determined subdividing the sand fraction into five classes. Higher amounts of the medium and fine sand fractions of the studied soils oriented their physical and hydric characteristics, being responsible for their great water retention. The arrangement of the fine silt, clay, fine sand and very fine sand particles may have provided a diversity of pore sizes and a good pore distribution, being responsible for the large proportion of micropores in the soils, allowing great water retention capacities.

This paper focused on the use of the biogeochemical LOICZ (Land Ocean Interactions in the Coastal Zone) to investigate the dynamics of DIN and DIP nutrients among three highly urbanized tropical estuaries (Barra das Jangadas (BJ), Recife (RE) and Timbó (TB)), located in the northeastern region of Brazil. The input data were obtained through in situ measurements (2007) and governmental agency databases (2001-2007). The balances of the non-conservative elements showed that the RE and TB systems alternated between sources and sinks during the observation periods (0.2-0.8 mmoles DIP m-2 d-1 and 0.1-10 mmoles DIN m-2 d-1). The metabolism rates in the systems indicated that the BJ system was autotrophic during the two observation periods (10-26 mmoles C m-2 d-1), while the RE system was heterotrophic (9-12 mmoles C m-2 d-1). The river discharge rates observed during the period 2001-2007 showed averages ranging from 9.4±3.8 to 18.4±7.7 m3s-1. Measurements of the trophic status in the RE system during 2007 characterized the system as eutrophic, thereby demonstrating high levels of chlorophyll-a and inorganic nutrients. The applications of balance sheets modeling proved to be very useful toward understanding the dynamics of estuarine systems dominated by large urban centers.

Abstract: The present work investigated what the appropriate methods of hydrolysis of pectin for reducing compounds (RCs) production, employed as a substrate for cell growth of Cupriavidus necator. This microorganism has great importance industrial, because besides potential single cell protein (SCP), is the most studied microorganism for production of polyhydroxybutyrate (PHB), and both processes require high cell concentration with inexpensive substrates For this, it was compared to acid and enzymatic hydrolysis procedures, through rotational central composite experimental design, using pectin concentration (1.0%). It was analyzed as a variable response for both experimental design, the RCs' production. The best conditions of each procedure were used in study kinetics of RCs' production and as a substrate for cell growth of C. necator. The results indicated that the enzymatic hydrolysis method was the most efficient, with a 93.0% yield of RCs, while the yield for acid hydrolysis was 60.0%. The optimum conditions for enzymatic hydrolysis were an enzyme concentration of 10.01 UI/g (International Unit of enzyme per gram of pectin) and an agitation speed of 230.3 rpm. C. necator showed satisfactory growth in the media containing pectin hydrolysates, with specific growth rates (μMax) similar to those reported for other substrates.

The Bohnenblust-Hille polynomial and multilinear inequalities were proved in 1931 and the determination of exact values of their constants is still an open and challenging problem, pursued by various authors. The present paper briefly surveys recent attempts to attack/solve this problem; it also presents new results, like connections with classical results of the linear theory of absolutely summing operators, and new perspectives.

Brazil is the world's largest producer of orange and passion fruit, which are destined mainly for industrialization, generating grand volumes of wastes. The solid portion of these residues is a rich source of pectin - composed mainly of galacturonic acid and neutral sugars, which through the hydrolysis process can be used in biological conversion processes, as the production of polyhydroxyalkanoates (PHAs). This way, we characterized these wastes, followed by the extraction and hydrolysis of pectin for employ as a substrate for the cell growth of Cupriavidus necator. The results confirmed the large portion of pectin (almost 40 g.100g-1) and soluble sugars, present in these wastes. The hydrolyzed extract showed as a good source of carbon for the cell growth of C. necator with YX/S 0.56 and 0.44, µMax 0.27 and 0.21 for orange and passion fruit wastes respectively, similar to other carbon sources. This way, the extraction and hydrolysis of orange and passion fruit wastes for the cellular growth of C. necator, can be a good alternative to converting of residues in high value added product.

The Pernambuco Basin represents one of the most prominent regions for deep water oil and gas exploration off the Brazilian coast. This study aims to identify and describe the occurrence of carbonate buildups in the offshore regions of the basin. The study was based on an analysis of a set of 143 2D time-migrated seismic sections that cover the offshore region of the Pernambuco Basin. An interpretation of the seismic dataset was used to define the main seismic sequences related to the main regional pulses of deposition and to identify three main groups of carbonate buildups: 1) shelf margin reefs, 2) patch reefs, and 3) isolated carbonate buildups. The carbonate buildups formed in two main intervals during post-rift sequences of the Santonian-Maastrichtian and Paleocene-Middle Miocene, which extend the known periods of carbonate deposit formation in the basin. The formation of carbonate buildups was controlled by the tectonic evolution of the Pernambuco Plateau, which created a series of paleotopographic highs that enabled the establishment of oceanographically and climatically favorable conditions for carbonate formation and deposition. These findings are important for understanding the evolution of the basin and for future evaluations of its petroleum potential.

A series of arylamidines 3a-j was designed, synthesized and investigated for antimicrobial activity. Structures of the compounds were confirmed by IR, 1H-NMR and 13C-NMR and a 2D spectroscopic study was performed. A preliminary screening of the antimicrobial tests clearly showed that three out of ten arylamidines, viz, 3f, 3g and 3i, were effective against all the gram-negative bacteria: Klebsiella pneumoniae, Pseudomonas aeruginosa and Salmonella enteric; and against the yeast, candida albicans. Further, the Minimum Inhibitory Concentrations (MIC) against the bacteria and yeast were determined. All compounds 3a-d, 3f, 3g, 3i and 3j were also investigated for their low cytotoxic effects on tested cell lines. Compounds 3d and 3f were the most effective derivatives against HL-60 and HEp-2 cells, respectively, with IC50 value (2µg/mL), and low normal cells toxicity.

Yellow fever is an arthropod-borne viral disease that still poses high public health concerns, despite the availability of an effective vaccine. The development of recombinant viruses is of utmost importance for several types of studies, such as those aimed to dissect virus-host interactions and to search for novel antiviral strategies. Moreover, recombinant viruses expressing reporter genes may greatly facilitate these studies. Here, we report the construction of a recombinant yellow fever virus (YFV) expressing Gaussia luciferase (GLuc) (YFV-GLuc). We show, through RT-PCR, sequencing and measurement of GLuc activity, that stability of the heterologous gene was maintained after six passages. Furthermore, a direct association between GLuc expression and viral replication was observed (r2=0.9967), indicating that measurement of GLuc activity may be used to assess viral replication in different applications. In addition, we evaluated the use of the recombinant virus in an antiviral assay with recombinant human alfa-2b interferon. A 60% inhibition of GLuc expression was observed in cells infected with YFV-GLuc and incubated with IFN alfa-2b. Previously tested on YFV inhibition by plaque assays indicated a similar fold-decrease in viral replication. These results are valuable as they show the stability of YFV-GLuc and one of several possible applications of this construct.

The focus of this study was to test the hypothesis that there would be no difference between the biocompatibility of resin-modified glass ionomer cements. Sixty male Wistar rats were selected and divided into four groups: Control Group; Crosslink Group; RMO Group and Transbond Group. The materials were inserted into rat subcutaneous tissue. After time intervals of 7, 15 and 30 days morphological analyses were performed. The histological parameters assessed were: inflammatory infiltrate intensity; reaction of multinucleated giant cells; edema; necrosis; granulation reaction; young fibroblasts and collagenization. The results obtained were statistically analyzed by the Kruskal-Wallis and Dunn test (P<0.05). After 7 days, Groups RMO and Transbond showed intense inflammatory infiltrate (P=0.004), only Group RMO presented greater expression of multinucleated giant cell reaction (P=0.003) compared with the control group. After the time intervals of 15 and 30 days, there was evidence of light/moderate inflammatory infiltrate, lower level of multinucleated giant cell reaction and thicker areas of young fibroblasts in all the groups. The hypothesis was rejected. The Crosslink cement provided good tissue response, since it demonstrated a lower level of inflammatory infiltrate and higher degree of collagenization, while RMO demonstrated the lowest level of biocompatibility.

This work evaluated the effects of ionizing radiation on the physico-chemical and sensory characteristics of the potato cultivar Ágata (Solanum tuberosum L.), including budding and deterioration, with the end goal of increasing shelf life. For this, four groups of samples were harvested at the maturation stage. Three of them were separately exposed to a Co-60 source, receiving respective doses of 0.10, 0.15 and 2.00 kGy, while the non-irradiated group was kept as a control. All samples were stored for 35 days at 24 °C (± 2) and at 39% relative humidity. The following aspects were evaluated: budding, rot, loss of weight, texture, flesh color, moisture, external and internal appearance, aroma, soluble solids, titratable acidity, vitamin C, protein, starch and glucose. The results indicated that 0.15 kGy was the most effective dose to reduce sprouting and post-harvest losses, under the conditions studied.

This work reports the dating of a fossil human tooth and shell found at the archaeological site Toca do Enoque located in Serra das Confusões National Park (Piauí, Brazil). Many prehistoric paintings have been found at this site. An archaeological excavation unearthed three sepulchers with human skeletons and some shells. Two Brazilian laboratories, in Ribeirão Preto (USP) and Recife (UFPE), independently performed Electron Spin Resonance (ESR) measurements to date the tooth and the shell and obtain the equivalent dose received by each sample. The laboratories determined similar ages for the tooth and the shell (~4.8 kyBP). The results agreed with C-14 dating of the shell and other samples (charcoal) collected in the same sepulcher. Therefore, this work provides a valid inter-comparison of results by two independent ESR-dating laboratories and between two dating methods; i.e., C-14 and ESR, showing the validity of ESR dating for this range of ages.

The present work aimed to magnetize Parkia pendula seeds gum and use it as a matrix for Concanavalin A covalent immobilization. This composite was applied in affinity purification of glycoconjugates. Parkia pendula seeds were hydrated and the gum provenient from the supernatant was precipitated and washed with ethanol and dried. The gum was magnetized in co-precipitation using solutions of Fe+2 and Fe+3. Matrix activation was accomplished with NaIO4. Magnetized Parkia pendula seeds gum with covalently immobilized Concanavalin A was used as an affinity matrix for the recognition of bovine serum fetuin glycoprotein. Fetuin elution was carried out with a solution of glucose (300mM) and evaluated through SDS-PAGE. The efficiency of lectin immobilization and fetuin purification were 63% and 14%, respectively. These results indicate that the composite produced is a promising magnetic polysaccharide matrix for lectins immobilization. Thus, such system can be applied for affinity purification allowing an easy recovery by magnetic field.

This study reports the first known occurrence of the Ediacaran fauna in northeastern Brazil (at Pacujá Municipality, northwestern state of Ceará) and presents preliminary interpretations of its significance. Regional correlation indicates that the fossils originated in the Jaibaras Basin and that they may represent a new geological system. The depositional environment can be attributed to a fluviomarine system. Nine Ediacaran species can be identified, including members of pandemic groups (e.g., Charniodiscus arboreus Glaessner, 1959; ?Charniodiscus concentricus Ford, 1958; Cyclomedusa davidi Sprigg, 1947; Ediacaria flindersi Sprigg, 1947; and Medusinites asteroides Sprigg, 1949) and endemic groups (e.g., Kimberella quadrata Glaessner & Wade, 1966; Palaeophragmodictya reticulata Gehling & Rigby, 1996; Parvancorina minchami Glaessner, 1958; and Pectinifrons abyssalis Bamforth, Narbonne, Anderson, 2008). Three ichnogenera are also present: Arenicolites Salter, 1857; Palaeophycus Hall, 1987; and Planolites Nicholson, 1873. The relative age of the deposits is between ?Ediacaran and Cambrian, and the fauna resembles the White Sea Assemblage. The bioturbation presents typical unbranched Ediacaran ichnogenera with little depth in the substrate. This previously unknown occurrence of the Ediacaran fauna reinforces the importance of the state of Ceará to Brazilian and global palaeontology.

The edible sea urchin Echinometra lucunter (Linnaeus, 1758) is a very common species on the sublittoral-midlittoral in Brazilian rocky shores. The aim of this work was to describe the gametogenesis and reproductive strategy of the E. lucunter population at Muro Alto beach in the Northeast coast of Brazil from August 2004 to August 2005. A total of 240 specimens were collected on the sandstone reef flat from a tidepool during spring low tides. The overall sex ratio was1.12:1,withoutsignificanttemporalvariationexceptinOctober2004. Firsts sexual maturity ocurred in individuals from a diameter of 20.8 mm. There was not a significant difference in gonad index between females and males during the sampling period. The female's gonad index variation was associated with a well-defined spawning, corroborated by the histological analysis of the gonads, which demonstrates sex differences of the gamete production. By contrast, the males showed no clear pattern. It is suggested that continuous reproduction with seasonal peaks in the E. lucunter population occurs at Muro Alto beach.