Removal of bromophenol blue anionic dye from water using a modified exuviae of Hermetia illucens larvae as biosorbent.

Organic dyes originating from liquid effluents from the textile industries are harmful to the environment. They are toxic and reduce the penetration of light into aquatic environments. In this study, a biosorbent was produced from the exuviae of Hermetia illucens (Linnaeus) larvae and used to remove organic anionic dyes from an aqueous medium. The solids were characterized in terms of thermal stability, chemical structure, morphology, and porosity using thermogravimetric (TGA), differential thermal analysis (DTA), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and N2 adsorption-desorption. There were studied the effects of pH and dosage of the adsorbent on the adsorption of the bromophenol blue dye, used as a model molecule. The adsorption kinetics was studied with Lagergren's pseudo-first-order rate model. The maximum adsorbed amount was 571 mg g-1 according to Langmuir's model. The adsorption process was evaluated as exothermic and spontaneous and was classified as physical adsorption. The prepared biosorbent was tested in five consecutive adsorption cycles achieving 99% dye removal at each stage. This demonstrated the maintenance of adsorption efficiency and desorption capacity. These results suggest that prepared biosorbent have potential applications in the treatment of effluents from textile industries.

Effects of urbanization on water quality in a watershed in northeastern Brazil.

Changes to land use generate imbalances in the natural dynamics of aquatic ecosystems. These changes can vary according to the specific characteristics of each environment and due to seasonal factors, reinforcing the importance of studies in this area in different regions of the globe. Thus, the aim of this study was to analyze the effects of land use change on the rivers and streams of the Cachoeira River Basin in the Northeast of Brazil. Samples were collected bi-monthly at 16 points along the basin over 1 year and analyzed for physical and chemical parameters (temperature, pH, conductivity, and percentage saturation of dissolved oxygen), inorganic nutrients (NO3-, NO2-, NH4+/NH3, PO43-, SiO4) and dissolved major ions (Ca2+, K+, Mg2+, Na+, HCO3-). The highest concentrations of NO3-, NO2-, NH4+/NH3, and PO43- occurred at the points with the highest percentage of urban areas and population density. The major ions Ca2+, K+, Mg2+, Na+, and HCO3- were positively correlated with the percentage of pasture coverage; however, the high concentrations of these ions and the strong correlation between them revealed that other factors besides land use, such as soil cover, geological formation, and water deficit, may be jointly contributing to increases in their concentrations. Thus, the results show that urbanization represents the type of land use with the greatest negative effect on water quality since it alters the concentrations of inorganic nutrients dissolved in the Cachoeira River Basin.

Influence of land use on trophic state indexes in northeast Brazilian river basins.

Eutrophication is a natural process within the ecological succession of aquatic ecosystems that results from nutrient inputs to water bodies, especially limiting elements such as phosphorus and nitrogen. However, the anthropogenic activities in river basin influence areas accelerate the eutrophication process of water bodies. Eutrophication is a global problem and considered one of the most relevant reasons of aquatic environments' degradation. In this context, watercourses that make up the Eastern Water Planning and Management Region (RPGA) receive high pollutant contributions due to release of wastewater and agriculture diffuse sources from cities located in influence area. The present study aims to evaluate the land use effect in trophic state of the water bodies in Eastern RPGA basins. The Carlson Trophic State Index in 1977, adjusted by Lamparelli 2004, was used to determine the eutrophication degree of the three river basins (Almada, Cachoeira, and Una) located in the Eastern RPGA. The nutrient and chlorophyll a data were obtained from the Monitoring Program (Monitora) of Environment and Water Resources Institute of Bahia (INEMA), covering the period from 2008 to 2015, at thirteen (13) sampling sites, with quarterly collections. The results showed that, among three basins analyzed, Cachoeira River basin presented the worst values for trophic state index (TSI) due to the high level of anthropization, while best results were found in Una basin. It was verified that land use exerted a significant influence on the water quality of bodies of water evaluated.

Determination and Evaluation of Metallothionein and Metals in Mugil cephalus (Mullet) from Pontal Bay, Brazil.

To assess environmental contamination, studies have been increasingly carried out using biomarkers to diagnose the effects of toxic metal exposure, such as metallothionein (MT). In this context, the aims of the present study were to determine Cd, Cu, Ni and Pb concentrations, by ICP-MS, in liver samples from Mugil cephalus from the municipality of Ilhéus, located in North-Southeastern Brazil, in the state of Bahia, which has been increasingly suffering from anthropogenic pressure, and to quantify total MT in liver and gills. Among essential metals, copper (199.2 µg g-1) presented concentrations approximately 7 times higher than allowed by the World Health Organization (30 µg g-1). Liver samples showed higher concentrations than gills. Metallothionein concentrations indicate differential contamination along the study area. The first sampling showed higher induction of MT synthesis overall. Differences between liver and gill MT concentration trends were relatively minor, which may indicate the adequacy of analyzing gills in an environmental monitoring context.

Mycelial development preceding basidioma formation in Moniliophthora perniciosa is associated to chitin, sugar and nutrient metabolism alterations involving autophagy.

We identified and characterized two chitinases, named MpCHIT1 and MpCHIT2, from the fungus Moniliophthora perniciosa - the etiologic agent of witches' broom disease in cacao tree (Theobroma cacao L.) - during its development, mainly in the mycelia phases preceding the basidioma formation. The expression of MpCHIT1 and MpCHIT2, together with MpCHS and MpATG8 (chitin synthase and autophagy genes, respectively), was analyzed during the M. perniciosa growth and development on bran-based solid medium as well as in liquid medium containing H2O2 or rapamycin (oxidative and nutritional related-autophagy stress agents, respectively). In order to link the expression of chitin metabolism-related genes to nutritional composition influencing fungus development, we also quantified total and reduced sugars, as well as macro- and micronutrients in the bran-based solid medium. The expression analysis showed that the MpCHS expression increased through mycelial development and then decreased in the primordium and basidioma phases, while the expression of MpCHIT1 and MpCHIT2 was higher in basidioma and primordium phases, respectively. Moreover, the expression pattern of MpCHIT1 and MpCHIT2 is distinct, the second correlated with the MpATG8 expression pattern and possibly with autophagy process, while the first may be related to the basidioma formation. The quantification of total and reduced sugars, as well as macro- and micronutrients supported the idea that the cell wall restructuration due to MpCHS, MpCHIT1 and MpCHIT2 is related to stress and fungal nutrient reallocation, allowing the formation and development of the basidioma. Experiments involving M. perniciosa growth on liquid medium containing H2O2 or rapamycin showed that MpCHIT1 and MpCHIT2 were over-expressed in response to oxidative but also to nutritional related-autophagy stresses. Interestingly, the expression level of MpCHS, MpCHIT1 and MpCHIT2 in presence of rapamycin is similar to the one observed in the primordium and basidioma from bran-based solid medium. The analysis of the overall data allowed designing a general scheme of chitin metabolism and autophagy during M. perniciosa development, focusing on the mycelium phases as crucial and environmentally influenced steps preceding the primordium and basidioma formation. These data support the idea that the nutritional environment of M. perniciosa influences its development and life cycle.

Methylxanthine and Flavonoid Contents from Guarana Seeds (Paullinia cupana): Comparison of Different Drying Techniques and Effects of UV Radiation.

Guarana seeds are typically processed using one of three drying methods: traditional sun exposure, greenhouse drying, or the alguidar oven technique. In our research, we evaluated the contents of methylxanthines and flavan-3-ols in sun- and alguidar-dried guarana seeds from Bahia State's Low Sul Identity Territory. Caffeine, theobromine, catechin, and epicatechin were determined by high-performance liquid chromatography with UV-visible detection (HPLC/UV-vis). Statistical tools, including analysis of variance (ANOVA), Tukey's test, and exploratory analysis, were employed to analyze the obtained data. Our findings indicated that the flavan-3-ols content in sun-dried guarana samples was lower compared to those dried using the alguidar oven, possibly due to exposure to ultraviolet radiation from solar energy. Conversely, we observed no significant differences (p > 0.05) in the average contents of methylxanthines between the two drying methods. Our supplementary experiments involving UV-A and UV-C radiation lamps revealed a decreasing trend in methylxanthines and flavan-3-ols contents with increasing duration of UV radiation exposure.

Illicit drugs in Brazil: environmental consequences and consumption patterns.

This article reviews the literature on the consumption, street drug analysis, distribution, and main environmental impacts of illicit drugs in Brazil and analyzes the III National Survey on Drug Use by the Brazilian Population. The literature review is based on articles published in national and international journals between 2018 and 2023. This review consists of two analyses, the first of which addresses publications from the last 6 years on the monitoring of illicit drugs in Brazil and a second analysis based on the III National Survey on Drug Use that addresses the different possibilities of contact with drugs. The results revealed that the Southeast region of Brazil has the highest number of studies on the subject, especially in the state of São Paulo, while the North and Northeast regions have the lowest number of studies. The Midwest regions only have studies in the federal capital city, Brasília, while no studies were found in states bordering countries that produce illicit drugs, such as Paraguay and Bolivia. Analytical methods that use the concept of miniaturization, green chemistry, and the adoption of acceptance methods are frequent in most articles. Chemometric and statistical tools are widely used for the analysis, development, and conclusion of identification and quantification methods. Among the articles studied, there was a predominance in the analysis of cocaine metabolites and cannabis metabolites in the aquatic environment, where their concentrations ranged from 0.01 to 2000 ng L-1. Studies also reported bioaccumulation in marine biota with concentrations of up to 4.58 µg kg-1 for mussels and sediments, posing a risk to algae, crustaceans, and fish. Furthermore, the data show that the consumption of illicit drugs is increasing in Brazil, especially among young people.

Comparison between water quality indices in watersheds of the Southern Bahia (Brazil) with different land use.

The present study evaluated the influence of land use and occupation on water quality indices (WQI); the WQI developed by the National Sanitation Foundation (NSF), the WQI adapted by the Environmental Company of the São Paulo State (CETESB), WQI proposed by Bascarón and the Canadian Council of Ministers of the Environment (CCME) WQI, obtained for watersheds located in the Eastern Water Planning and Management Region (BA). The study also analyzed the divergences and similarities of these WQI methods. Water quality data were obtained from the Monitoring Program (Monitora) of Environment and Water Resources Institute of Bahia (INEMA), covering the period from 2008 to 2015, at thirteen (13) sampling sites, with quarterly collections, as well as land use and occupation data. The influence of land use and occupation on water quality indices was assessed by principal component analysis (PCA). The PCA showed that urban and agricultural/pasture areas were influencing factors on water quality variables, such as total phosphorus, biochemical oxygen demand, total nitrogen, turbidity total residues and consequently lower WQI values in the Cachoeira watershed. Among the tested methods to evaluate the water quality of watersheds in the study area, the most similar were the NSF WQI, CETESB WQI, and Objective Bascarón WQI.

Multivariate optimization of an ultrasound-assisted extraction procedure for the determination of Cu, Fe, Mn, and Zn in plant samples by flame atomic absorption spectrometry.

In this work, a simple, easy, and fast ultrasound-assisted extraction procedure for the determination of Cu, Fe, Mn, and Zn in plant samples was developed. Sample preparation conditions were optimized in a multivariate manner using mixture design and Box-Behnken. The extraction conditions adequate to obtain the maximum response were 90% power, 10 minutes, 40 °C temperature, and using an extraction solution composed of HNO3 and HCl at a concentration of 0.5 and 1.1 mol L-1, respectively, for a volume of 10 mL and 250 mg of samples. Accuracy was verified from the analysis of a certified reference material (Apple leaves, NIST 1515) yielding recoveries between 89 and 98% for the procedure. Precision was evaluated in a repeatability study (n = 10), yielding RSDs less than 6.7%, and the limits of quantification (mg kg-1) were 0.95, 2.42, 1.31, and 1.18 for Cu, Fe, Mn, and Zn, respectively. The concentrations determined in the stem and leaf of the mangrove species varied according to the collection point and the tissue, being consistent with other studies. The proposed procedure was efficient and reliable for elemental determination in plant samples, with the advantages of low cost and reagent consumption besides short analysis time as a valid alternative to the conventional sample preparation procedure.

Artificial neural network employment for element determination in Mugil cephalus by ICP OES in Pontal Bay, Brazil.

Fish are important sources of protein, making them very significant in the human diet. Although the consumption of this food is beneficial for health, it is essential that the product does not contain inorganic components above the limits recommended by the current legislation. Therefore, a method for determination of elements in fish (Mugil cephalus) samples was optimized. A simplex centroid mixture design with restriction was applied for optimization of the acid digestion of samples in an open system under reflux in order to evaluate the best ratio between the reagents HNO3, H2O2 and H2O. The results indicated that more intense analyte signals were obtained when a mixture containing 3.6 mL of HNO3 (65% v/v), 0.4 mL of H2O2 (30% v/v) and 6.0 mL of H2O was used. The accuracy of the method was assessed with a CRM of oyster tissue (NIST 1566b). The method presented relative standard deviations (RSDs) of 3.54%; 3.82%; 4.81% and 3.50% for Zn, Fe, Cu and S, respectively. The detection limits were 0.002 mg kg-1 for Cu and Zn and 0.02 mg kg-1 for Fe and S. The proposed method was applied for the determination of Zn, Fe, Cu and S in fish samples. A Kohonen Self-Organizing Map (KSOM) with K-means implementation was applied to better delimit the boundary between groups and the spatial and temporal influence on how concentrations of the chemical elements were perceived. To verify the separation, the Davies-Bouldin and Silhouette indices were used, obtaining 0.5374 and 0.8541, respectively, indicating satisfactory separation.

Development of procedure for sample preparation of cashew nuts using mixture design and evaluation of nutrient profiles by Kohonen neural network.

A procedure using ICP OES for sample preparation for the determination of copper, iron and manganese in cashew nuts was developed. Constrained simplex-centroid design was applied in the optimization of the digestion in microwave oven procedure, and the results evaluated from topological maps of the Kohonen network. The best proportion evaluated for the digestion of the sample with HNO3, H2O2 and H2O was 10:45:45 (%). With optimized conditions, the detection limits were 0.63, 4.3 and 0.37 mg kg-1, and quantification 2.1, 14 and 1.2 mg kg-1 for Cu, Fe and Mg, respectively. The precision (% RSD) was 1.84, 2.31 and 2.73, for Cu, Fe and Mg, respectively. The procedure proposed had the accuracy confirmed using NIST 1568b (at 95% reliability) and was applied in the samples obtaining concentrations in the range of 10.7-19.4, 44.3-67.2 and 11.0-21.4 mg kg-1 for Cu, Fe and Mg, respectively.

Chemical profiling of guarana seeds (Paullinia cupana) from different geographical origins using UPLC-QTOF-MS combined with chemometrics.

Paullinia cupana, commonly known as guarana, is an Amazonian fruit whose seeds are used to produce the powdered guarana, which is rich in caffeine and consumed for its stimulating activity. The metabolic profile of guarana from the two largest producing regions was investigated using UPLC-MS combined with multivariate statistical analysis. The principal component analysis (PCA) showed significant differences between samples produced in the states of Bahia and Amazonas. The metabolites responsible for the differentiation were identified by orthogonal partial least squares discriminant analysis (OPLS-DA). Fourteen phenolic compounds were characterized in guarana powder samples, and catechin, epicatechin, B-type procyanidin dimer, A-type procyanidin trimer and A-type procyanidin dimer were the main compounds responsible for the geographical variation of the samples.

Morphology, ultrastructure, and element uptake in Calophyllum brasiliense Cambess. (Calophyllaceae J. Agardh) seedlings under cadmium exposure.

Cadmium (Cd) is a metal known for its genotoxicity and cytotoxicity, much concerned for its potential environmental and human health impacts. This study evaluates the toxic effect of Cd in Calophyllum brasiliense plants. The plants were cultivated for 30 days in full nutrient solution in order to adapt, and for 15 days in nutrient solution without Cd or with 4, 8, 16, and 32 µmol Cd L-1. Anatomical analysis of the leaf showed no significant effects of Cd on epidermal thickness in abaxial and adaxial sides, palisade, and spongy parenchyma. Contrastingly, changes were noticed in the ultrastructural level in the leaf mesophyll cells as rupture of the membrane of chloroplasts and disorganization of the thylakoid membranes, in starch grains and in mitochondria with rupture of the membrane and invagination of the nuclear membrane. Electron dense materials into cells of the cortex and vascular bundle were also observed. In the cells of the root system, the observed ultrastructural changes were disruption of the cell wall and electron dense material deposition in the cortex cells and vascular region. Cd accumulated in roots with low translocation into shoot. Cd toxicity also affected the photosynthetic activity, inducing stomatal closure and photosynthetic assimilation reduction and the instantaneous carboxylation efficiency, drastically reducing the leaf transpiration. The nutrient content in the stem and root was variable, according to Cd increase in nutrient solution. Based on the experimental evidence, it can be concluded that C. brasiliense has potential to bioconcentrate high Cd levels in the root system.

Morphology, ultrastructure and mineral uptake is affected by copper toxicity in young plants of Inga subnuda subs. luschnathiana (Benth.) T.D. Penn.

Toxic effects of copper (Cu) were analyzed in young plants of Inga subnuda subs. luschnathiana, a species that is highly tolerant to flooding and found in Brazil in wetlands contaminated with Cu. Plants were cultivated in fully nutritive solution, containing different concentrations of Cu (from 0.08 µmol to 0.47 mmol L(-1)). Symptoms of Cu toxicity were observed in both leaves and roots of plants cultivated from 0.16 mmol Cu L(-1). In the leaves, Cu clearly induced alterations in the thickness of the epidermis, mesophyll, palisade parenchyma, and intercellular space of the lacunose parenchyma. Also, this metal induced disorganization in thylakoid membranes, internal and external membrane rupture in chloroplasts, mitochondrial alterations, and electrodense material deposition in vacuoles of the parenchyma and cell walls. The starch grains disappeared; however, an increase of plastoglobule numbers was observed according to Cu toxicity. In the roots, destruction of the epidermis, reduction of the intercellular space, and modifications in the format of initial cells of the external cortex were evident. Cell walls and endoderm had been broken, invaginations of tonoplast and vacuole retractions were found, and, again, electrodense material was observed in these sites. Mineral nutrient analysis revealed higher Cu accumulation in the roots and greater macro- and micronutrients accumulation into shoots. Thus, root morphological and ultrastructural changes induced differential nutrients uptake and their translocations from root toward shoots, and this was related to membrane and endoderm ruptures caused by Cu toxicity.

Effects of lead on anatomy, ultrastructure and concentration of nutrients in plants Oxycaryum cubense (Poep. & Kunth) Palla: a species with phytoremediator potential in contaminated watersheds.

Lead (Pb) has been highlighted as a major pollutant of both terrestrial and aquatic ecosystems, causing negative impacts to these environments. The concentration of Pb in plants has increased in recent decades, mainly due to anthropogenic activities. This study has as a hypothesis that the species Oxycaryum cubense (Poep. & Kunth) Palla, abundant in aquatic environments, has the potential to be used a phytoremediator. The plants were grown in a hydroponic system with Pb in increasing concentrations (0, 4, 8, 16 and 32 mg l(-1)) for 15 days. Inductively coupled mass spectrometer (ICP OES) was used to determine the concentration of mineral nutrients and lead. Optical and transmission electron microscopy were used for the analysis of cellular damage induced by lead in roots and leaves. Ultrastructural alterations were observed as disorganization of thylakoids in the chloroplast and disruption of mitochondrial membranes in cells of leaf tissues of plants subjected to increasing Pb concentrations. There was accumulation of Pb, especially in the root system, affecting the absorption and translocation of some mineral nutrients analysed. In roots, there was reduction in the thickness of the epidermis in plants treated with Pb. This species was shown to be tolerant to the Pb concentrations evaluated, compartmentalizing and accumulating Pb mainly in roots. Due to these results, it may be considered a species with phytoremediation capacity for Pb, with potential rizofiltration of this metallic element in contaminated watersheds.