TESE DE DOUTORADO - PROGRAMA DE PÓS-GRADUAÇÃO EM REDE - REDE DE BIODIVERSIDADE E BIOTECNOLOGIA DA AMAZÔNIA LEGAL/CCBS
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Item Óleos essenciais e terpenos como estratégia de controle de carrapatos e nematoides(Universidade Federal do Maranhão, 2022-12-15) SOUSA, Anildes Iran Pereira; COSTA JÚNIOR, Livio Martins; http://lattes.cnpq.br/6651961821189728; SOARES, Alexandra Martins dos Santos; http://lattes.cnpq.br/6434212774237352; SOARES, Alexandra Martins dos Santos; http:/lattes.cnpq.br/6434212774237352; PINTO, Mayara Cristina da Silva; http:/ lattes.cnpq.br/9507590466760552; RIBEIRO, Rachel Melo; http:/lattes.cnpq.br/4752952470368965; CARTÁGENES, Maria do Socorro de Sousa; http:/lattes.cnpq.br/3013333572719007; BRITO, Danilo Rodrigues Barros; http:/lattes.cnpq.br/05978401614863Ticks and nematodes are widely distributed parasites of veterinary importance. The continuous use of synthetic acaricides and anthelmintics has resulted in increased resistance. Thus, therapeutic alternatives such as natural products have been considered. The parasitic activity of plant essential oils (EOs) and their components have been investigated against ticks and nematodes. This study aimed to evaluate essential oils and terpenes as a strategy to control nematodes and ticks. The action of essential oils (EOs) obtained from 16 cultivars of Ocimum basilicum, linalool, methyl chavicol, citral and eugenol was evaluated in vitro in the test of inhibition of the hatching of eggs of the nematode Haemonchus contortus. Additionally, the action of three cultivars was evaluated, which were simulated using a combination of the two main compounds of each one. For the tick studies, a shampoo containing carvacrol was formulated with sodium lauryl ether sulfate, cocoamidopropyl betaine, lauryl glucoside, carboxymethyl cellulose, methyl paraben and citric acid. The shampoo's sensory characteristics and pH were evaluated at 37, 25 and 5 °C. The effectiveness of shampoo containing carvacrol against R. microplus and R. sanguineus was evaluated by the larval immersion test. Regarding the tests on nematodes, the EOs from different cultivars of O. basilicum showed a concentration to inhibit 50% of the hatchability of eggs (IC50) of H. contortus, ranging from 0.56 to 2.22 mg/mL. The cultivar with the most significant inhibition of egg hatching, napoletan, consists mainly of linalool and methyl chavicol. Among the individual compounds tested, citral was the most effective (IC50 0.30 mg/mL). The best combination of compounds was obtained with 11% eugenol and 64% linalool (IC50 0.44 mg/mL). As a result of the assessments on ticks, the mortality of R. microplus and R. sanguineus was 100% after treatment with 0.15% shampoo containing carvacrol (1:19 dilution of shampoo in water). The shampoo with carvacrol was stable under the conditions analyzed. We conclude that different cultivars of O. basilicum have different efficacies against H. contortus, with the cultivars containing linalool and methyl chavicol being the most promising; we also conclude that the shampoo containing carvacrol has acaricidal efficacy and is a potential tick control agent.Item Avaliação da atividade antitumoral da fração diclorometânica obtida das raízes de Arrabidaea brachypoda (DC BUREAU)(Universidade Federal do Maranhão, 2022-08-30) SILVA, Vera Lucia Maciel; ROCHA, Claudia Quintino da; http://lattes.cnpq.br/5609489233382242; PEREIRA, Silma Regina Ferreira; http://lattes.cnpq.br/8510523766431676; PEREIRA, Silma Regina Ferreira; http://lattes.cnpq.br/8510523766431676; TAVARES, Denise Crispim; http://lattes.cnpq.br/5342181863190744; MONTEIRO, Cristina de Andrade; http://lattes.cnpq.br/2495926580105868; NASCIMENTO, Maria do Desterro Brandão; http://lattes.cnpq.br/3958174822396319; COSTA, Maria Célia Pires; http://lattes.cnpq.br/4515777673951926Cancer affects millions of people, representing one of the biggest public health problems worldwide. Available treatments have several adverse effects and little specificity. Thus, the need for more effective therapeutic options, with less toxicity and greater specificity, has intensified the search for new drugs. Arrabidaea brachypoda is a native plant of the Brazilian Cerrado known as "cipó-una", "santo cipó", "cervejinha do campo", popularly used in the treatment of inflammation, kidney stones and pain. Our main aim was to evaluate the antitumor potential of the dichloromethane fraction (DCMF) obtained from A. brachypoda roots, whose components are three dimeric flavonoids of unusual structures, called brachydins. Sulforhodamine B assay results revealed DCMF cytotoxicity, and the impact of fetal bovine serum (FBS) on this activity. In silico analysis showed strong affinity between serum albumin and brachydins, confirming the impact of FBS concentration on the antitumor activity of DCMF. Based on this, cancer cells from breast (MCF7), cervix (HeLa), prostate (DU145), as well as non-tumor prostate cells (PNT2), were maintained in culture medium with 1% FBS and treated with different DCMF concentrations (1 to 8 μg/mL). Assays revealed IC50's of 2.77, 2.46, 2.51 μg/mL and 4.08 μg/mL for MCF7, Hela, DU145 and PNT2, respectively. Genotoxicity analysis by the comet assay revealed that DCMF does not cause DNA damage when both tumor and non -tumor cells are exposed to 1⁄2 IC50, IC50 and double IC50 for 3 and 24 hours. In addition, DCMF inhibited colony formation (by clonogenic assay) of tumor cells in a concentration-dependent manner (r = -0.944, p <0.05), with almost total inhibition in HeLa and MCF7 cells exposed to their respective IC50. Additionally, treatments with 2.5 μg/mL and 1.25 μg/mL significantly inhibited DU145 colony formation by 87.3 and 39.2%, respectively. Cell migration was evaluated by the wound healing assay, which revealed reduced mobility of DU145 cells (r = -0.751, p < 0.05), whereas there was no effect on the PNT2 cell line. Atomic Force Microscopy (AFM) analysis revealed ultrastructural changes (holes) on the nuclear membrane surfaces of DCMF-treated DU145 cells. Additionally, there was a positive correlation between cell membrane roughness and fraction concentration (r= 0.857, p < 0.05), with 7.9 ± 0.43 nm for untreated cells, and 11.6 ± 1.42 nm and 15.37 ± 3.9 for tumor cells exposed to 2.5 μg/mL and 1.25 μg/mL, respectively. All these findings support the antitumor activity of DCMF and suggest that the induction of ultrastructural changes in the cell membrane may be one of the mechanisms of action of brachydins.Item Estudo de catalisadores bimetálicos Ni-Ag para a eletrooxidação de pequenas moléculas orgânicas visando à aplicação em fontes de energia sustentável(Universidade Federal do Maranhão, 2022-08-31) SANTOS, José Ribamar Nascimento dos; MARQUES, Edmar Pereira; http://lattes.cnpq.br/2468528554511482; MARQUES, Aldaléa Lopes Brandes; http://lattes.cnpq.br/0121030502015990; LEMOS, Sherlan Guimarães; http://lattes.cnpq.br/1602277501575415; DAMOS, Flávio Santos; http://lattes.cnpq.br/0915687070195770; NUNES, Gilvanda Silva; http://lattes.cnpq.br/5833210771020427; FIGUEREDO, Gilvan Pereira de; http://lattes.cnpq.br/3730724432445516Ni−Ag nanoparticles supported on reduced graphene oxide (rGO) were investigated as electrocatalysts for the oxidation of ethanol, ethylene glycol, glycerol, and urea. The NiXAg100- X/rGO catalysts (X = 0, 50, 66, 75, 90 and 100) were prepared by the chemical reduction method, using sodium borohydride (NaBH4) as a reducing agent and characterized by the Fourier transform infrared spectroscopy technique (FTIR), UV-Vis spectroscopy, X-ray diffraction, scanning electron microscopy (SEM) and X-ray energy dispersive spectroscopy (EDS). The electrocatalytic activity of the materials in alkaline medium was evaluated by cyclic voltammetry (CV), chronoamperometry and electrochemical impedance spectroscopy (EIS). FTIR and UV-Vis spectra revealed that most of the functional groups containing oxygen were removed from graphene oxide by reduction with NaBH4. Composites of Ni−Ag alloys supported on rGO showed higher electrocatalytic activity compared to monometallic Ni(OH)2/rGO for ethanol, ethylene glycol and glycerol oxidation. In addition, the theoretical composition Ni66Ag34/rGO showed the best catalytic activity for the oxidation of these alcohols. Chronoamperometric curves recorded at 0.5 V confirm the superior stability of Ni−Ag/rGO catalysts during the oxidation of ethanol, ethylene glycol and glycerol. Regarding the oxidation of urea, the Ni90Ag10/rGO catalyst presented an onset potential of 0.291 V (vs. Ag/AgCl) and a current density of 109.3 mA cm-2 at 0.6 V, which shows a performance improved compared to Ni(OH)2/rGO (0.325 V and 78.2 mA cm-2 ). Ni90Ag10/rGO also exhibits good current retention during urea oxidation (98.6% for 3600 s). The good performance of Ni−Ag/rGO catalysts is attributed to the effect of the rGO support, as well as the synergistic effect between Ni and Ag.Item ATIVIDADE ANTIMICROBIANA DE METABOLITOS SECUNDÁRIOS DE Streptomyces spp, ISOLADOS DE CULTURA DE SOJA DO SUL DO ESTADO DO MARANHÃO(Universidade Federal do Maranhão, 2021-12-17) ALVES, Matheus Silva; MIRANDA, Rita de Cassia Mendonça de; http://lattes.cnpq.br/1952235749528138; MIRANDA, Rita de Cássia Mendonça de; http://lattes.cnpq.br/1952235749528138; MONTEIRO, Andrea de Souza; http://lattes.cnpq.br/9268996030726117; ABREU JUNIOR, Afonso Gomes; http://lattes.cnpq.br/4394413983541820; FIRMO, Wellyson da Cunha Araújo; http://lattes.cnpq.br/2261911621272178; ALIANÇA, Amanda Silva dos Santos; http://lattes.cnpq.br/4475680269949975Brazil has an extensive territorial area with the presence of several biomes. Soil as abiotic components of biomes can be described as a grouping of chemical and biological reactions and processes responsible for the formation of land layers and plant development, where filamentous bacteria called Actinomycetes can be found. These microorganisms have a big capacity to produce bioactive compounds, which allows antagonism to other microorganisms in the competition relationship for space, causing injury and/or destruction of other organisms. Based in these aspects, the present work object to verify the antimicrobial action of secondary metabolites produced by Actinomycetes isolated from soil used for soybean planting in Maranhao state. For this, soil samples were collected and performed morphological and molecular identification tests, enzymatic and antimicrobial activity assays such as solid medium assay (agar block), liquid medium assay (diffusion agar), evaluation of the Minimum Inhibitory Concentration (MIC) and synergism against the microorganisms Klebsiella pneumoniae ATCC 0023, Pseudomonas aeruginosa ATCC 0026, Staphylococcus aureus ATCC 6538, Corynebacterium diphtheriae ATCC 27012, Cryptococcus gattii ATCC 24065 and preliminary chemical identification of the extracts. Ten strains were isolated, the mosto f them being Streptomyces. Of the isolates, only the strains Act 01, Act 03, Act 06 showed antimicrobial activities and these three isolates were identified as belonging to the genus Streptomyces. All three strains were able to produce cellulase, amylase and protease enzymes. In addition to presenting a halo of inhibition for all tested pathogens with the exception of Klebsiella pneumoniae. Regarding the CMI, it presented inhibition results for Pseudomonas aeruginosa ATCC 0026 (500 μg/mL), Staphylococcus aureus ATCC 6538 (1000 μg/mL), Cryptococcus gattii ATCC 24065 (125 μg/mL). Regarding the compounds isolated from the extract, the presence of flavonoids, terpenes and alkaloids was determined. Them, the Streptomyces isolates demonstrated antimicrobial action and more tests need to be carried out to ensure the biological safety of these bioactives.Item Método fotoeletroquímico utilizado como ferramenta para a determinação do ácido 3,4,5-tri-hidroxibenzóico e avaliação da sua capacidade antioxidante(Universidade Federal do Maranhão, 2022-02-25) LIMA, Kayni Cássea Moreira Soares; LUZ, Rita de Cássia Silva; http://lattes.cnpq.br/1282444701404832; LUZ, Rita de Cássia Silva; http://lattes.cnpq.br/1282444701404832; MARQUES, Edmar Pereira; http://lattes.cnpq.br/2468528554511482; SILVA, Gilmar Silvério da; http://lattes.cnpq.br/6983165980341102; CAVALCANTE, Kiany Sirley Brandão; http://lattes.cnpq.br/3810732989135120; LUZ, Roberto Alves de Sousa; http://lattes.cnpq.br/3929578675139228The present work is based on the development and application of a photoelectrochemical method used as a tool for the determination of the antioxidant 3,4,5-trihydroxybenzoic acid (THBA), a phenolic antioxidant, and evaluation of its antioxidant capacity (AA) in different samples. The method is based on the use of a photoelectrochemical platform based on a fluorine doped tin oxide (FTO) coated glass slide which has been modified with cadmium sulfide (CdS) and poly (D-glucosamine) (p-DG) and subjected to a radiation source (an LED light emitting diode). The modified electrode was denoted as FTO/CdS/p- DG, showed a fast photoelectrochemical response for analyte detection. The photoelectrochemical method used showed that there was subsequent decrease in the sensor response as the concentration of antioxidant THBA in solution was increased. The photoelectrochemical assays for AA evaluation were performed by monitoring the photocurrent generated after the addition of 2,2-diphenyl-1- picrylhydrazide (DPPH• ) to the solution and the presence of the antioxidant studied. Under optimized experimental and operational conditions, the FTO/CdS- p-DG sensor showed a linear concentration range for the analyte in the absence of DPPH• from 0.2 to 500 μmol L-1, with a detection limit of 0.1 μmol L-1. In the presence of the DPPH• radical a concentration range for THBA from 0.5 μmol L- 1 a 8.5 mmol L-1 was observed. The p-DG-CdS/FTO sensor was applied to samples of beverages such teas, juices and red wines. The obtained results suggest that the developed platform is a promising tool for the quantification of the antioxidant THBA and for the evaluation of the antioxidant activity of different food samples such as juices, wines, teas and plant extracts.Item Desenvolvimento de sensor a base nanotubo de carbono e óxido de ferro para determinação de BTX em água subterrânea e solo de postos de combustíveis em São Luís/MA(Universidade Federal do Maranhão, 2021-09-26) PINHEIRO, Helilma de Andréa; AZEVEDO, Lorena Carvalho Martiniano de; http://lattes.cnpq.br/8536193616269377; MARQUES, Aldalea Lopes Brandes; http://lattes.cnpq.br/0121030502015990; MARQUES, Aldaléa Lopes Brandes; http://lattes.cnpq.br/0121030502015990; OLIVEIRA, Marcelo Moizinho; http://lattes.cnpq.br/2390627324215152; SANTANA, Audirene Amorim; http://lattes.cnpq.br/7431678688628387; CAVALCANTE, Kiany Sirley Brandão; http://lattes.cnpq.br/3810732989135120; TELES, Rogério de Mesquita; http://lattes.cnpq.br/0873017441220537Environmental contamination by organic compounds represents serious problems for public health and the environment, especially for groundwater and soil contamination. One of the main problems is contamination by aromatic hydrocarbons. Among the monoaromatic hydrocarbons, known as BTX [benzene (B), toluene (T) and xylenes (X)], B stands out for being the most toxic among BTX, being considered highly carcinogenic, including their derivatives. Monitoring these contaminants in groundwater and soil of great importance. The present work proposes an electrochemical sensor based on iron oxide nanoparticles supported on carboxyl- functionalized multi-wall carbon nanotubes (ECV/Fe2O3/MWCNT-COOH) for the determination of B, T and X in soil and groundwater samples from gas stations. The physicochemical properties of Fe2O3/MWCNT-COOH were characterized by Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FT-IR) and X-ray Diffraction (XRD). Using the square wave voltammetry (SWV) technique the ECV/Fe2O3/MWCNT-COOH sensor was evaluated from the electroanalytical point of view for BTX analysis. After optimizing the experimental parameters, the following best conditions were found: electrolyte = H2SO4 0.1mol L-1 ; pH = 1.0; frequency = 40 mV; amplitude = 20 mV; potential step = 2 mV. Under these optimized conditions, the proposed sensor presented an excellent electroanalytical performance for BTX oxidation and analysis, showing a linear behavior between anode peak currents and analyte concentrations, in the range of 5 to 35 μmol L -1 for benzene, and 20.00 to 53.00 μmolL-1 for toluene and xylenes. Through the standard deviations of the calibration curves the LD were calculated for the analytes (0.78 μmol L-1 for benzene, 5.33 μmol L-1 for toluene and 20.38 μmol L-1 for xylenes). The precision (relative standard deviation (RSD) of the method) was assessed by the repeatability of the analyte current (n = 6) in the solution. Good RSD values were found (0.81% for benzene, 3.99% for toluene and 2.82% for xylene). The application of the new method was carried out through the enrichment in real samples. Recovery (accuracy) showed excellent statistical results in samples of soil (B = 99.9%; T = 100%% and X = 99.8%) and groundwater (B = 100%; T = 99.7% e X = 99.8%). No significant interferences were observed for other species (catechol and benzoquinone) possibly present in the analysis of each of the analytes. The good results indicate that the proposed new electrochemical nanosensor is suitable for the determination of BTX in soil and groundwater samples.Item Identificação de bactérias produtoras de compostos ativos de superfície, isoladas de sedimentos de mangue(Universidade Federal do Maranhão, 2022-02-17) NUNES NETO, Wallace Ribeiro; SANTOS, Vera Lucia dos; http://lattes.cnpq.br/2094571540679771; MONTEIRO, Andrea de Souza; http://lattes.cnpq.br/9268996030726117; MONTEIRO, Andrea de Souza; http://lattes.cnpq.br/9268996030726117; SILVA, Luís Cláudio Nascimento; http://lattes.cnpq.br/6016850820500623; MONTEIRO, Cristina de Andrade; http://lattes.cnpq.br/2495926580105868; FERREIRA, Gabriella Freitas; http://lattes.cnpq.br/7970414057350848; REZENDE, Rachel Passos; http://lattes.cnpq.br/6516440231429832Mangroves are zones of sediment transitions, favoring the cycling of materials, associated with a high concentration of microorganisms, presenting vulnerability to anthropogenic actions. This study aimed to evaluate the capacity of the microbiota in mangrove sediments from the river Anil, in the city of São Luís - MA for the production of surface active compounds (CASs). The sediment samples were collected according to the EMBRAPA 2006 methodology, being inoculated in Bushnell Haas medium, containing 1 gram of the sample for 250ml of medium plus 3% (v/v) kerosene. Being identified by the MALDI-QTOF MS method as Pseudomonas aeruginosa, capable of producing surface active compounds, PSA39. Submitted to E24 analysis, drop scattering, thermal/pressure stability, pH variation and ionic stability. The PSA39 genome was sequenced by the Illumina – MiSeq platform and the pre-assembled genomic DNA sequences were annotated using the Prokka software. The genomic sequence obtained was analyzed by Rapid Annotation using Subsystem Technology (RAST) to identify metabolic pathways associated with hydrocarbon degradation and biosurfactant production. BLAST genome distance phylogeny method (GBDP), in addition to mean nucleotide identity (ANI). Also, the genome of PSA39 was submitted to comparative analysis by MAUVE, using other strains deposited in GenBank. Orthologous gene clusters were identified using OrthoVenn 2. In this study, approximately 32 strains of bacteria were isolated from mangrove sediment samples, of which 32 isolates 9 showed emulsifying activity (E24). E24 values ranged from 13% to 57.30% analyzed. Isolate PSA39 was selected for studies of growth and production of a biosurfactant with emulsifying activity. The maximum production of compounds with emulsifying activity occurred within 100 hours. The emulsifying activity and stability tests with the biosurfactant recovered with ethyl acetate showed E24 values ranging from 57% to 69.2% of yield, with an increase in stability at basic pHs, reaching 79%, in addition to resisting the test of pressure and temperature autoclaving. Genome analysis of the P. aeruginosa PSA39 strain by RAST indicated the presence of genetic subsystems in a total of 2062 genes, 1946 of which related to non-hypothetical proteins and 571 genes related to hypothetical proteins. The genome of P. aeruginosa PSA39 showed genes related to pathways responsible for the production of rhamnolipids as secondary metabolites, many genes were related to the degradation of aromatic and lymphatic hydrocarbons, in addition to several genes related to the production of siderophores, such as pyoverdine and pyochelin. Furthermore, the analyzes performed by RAST indicated that P. aeruginosa PSA39 has several molecular mechanisms for adaptation to heavy metals, such as the protein, cobalt-zinc-cadmium (CzcC). One hundred and fifteen unique (exclusive) groups were identified in isolate PSA39 with proteins with defined functions, associated with conjugation, cellular and metabolic processes of hydrocarbons such as alcohols and aromatics visualized by the comparative genomic analysis "orthovenns" associated with the RAST platform. The results of this work allowed to demonstrate the viability of using regional microorganisms present in mangroves for the production of surface active compounds with emulsifying activity, from different carbon sources, as they have good emulsification rates and stability against the diversity of environmental factors.Item Estudo dos mecanismos associados à responsividade a terapia antirreumática(Universidade Federal do Maranhão, 2021-05-07) RODRIGUES, João Francisco Silva; FERNANDES, Elizabeth Soares; http://lattes.cnpq.br/9631573633970523; FERNANDES, Elizabeth Soares; http://lattes.cnpq.br/9631573633970523; MONTEIRO NETO, Valério; http://lattes.cnpq.br/5476942147520772; GUERRA, Rosane Nassar Meireles; http://lattes.cnpq.br/2316192786452127; ANDRÉ, Eunice; http://lattes.cnpq.br/8906770743620827; LIMA NETO, Lídio Gonçalves deRheumatoid arthritis (RA) affects thousands of people worldwide, about 1% of the world's adult population. It is defined as inflammation of one or more joints, with the presence of pain, swelling, erythema and increased temperature in the affected region. Current therapy consists of using non-steroidal anti-inflammatory drugs (NSAIDs), glucocorticoids, disease-modifying agents (DMARDS) and biological agents such as anti-TNF. Still, due to mechanisms that have not yet been fully elucidated, a portion of the patients does not respond to any existing therapeutic line, remaining at the same time to live with the progressive symptoms of this pathology. Initially, we conducted a pilot study to investigate the potential use of flow cytometry and infrared spectroscopy with attenuated total reflection Fourier transform (ATR-FTIR) as measures to identify responders and non-responders to leflunomide, a disease-modifying drug used in treatment of RA patients. By evaluating the number of CD62L + polymorphonuclear cells in peripheral blood and the vibrational ATR-FTIR modes in plasma, it was possible to discriminate responders to LFN three months after the start of therapy. The results indicate that both flow cytometry and ATR-FTIR can potentially be used as additional measures to monitor an early treatment response to LFN in RA patients. In the second manuscript, we investigated RA markers in peripheral blood, using a model of CFA-induced joint inflammation in CD1 mice, we were able to identify responders and non-responders to Adalimumab (Ada) (100 μg / mouse / week; 3 weeks). Ada responders exhibited a reduced population of CD8+ CD69+ cells, as well as decreased expression of MHC II-associated genes (H2-Ea and H2-Eb1) in their peripheral blood leukocytes. These results demonstrate that CFA-induced arthritis in CD1 mice can be used as a useful non-clinical model of joint inflammation to investigate anti-TNF drugs, as well as the mechanisms underlying the chances of success and failure of such therapies in RA.Item EFEITO DO CINAMALDEÍDO EM MODELOS DE PATOLOGIA CUTÂNEAS CAUSADAS POR Staphylococcus aureus.(Universidade Federal do Maranhão, 2019-07-22) FIGUEIREDO, Cristiane Santos Silva e Silva; GRISOTTO, Marcos Augusto Grigolin; 115.272.168-29; http://lattes.cnpq.br/5716933213935304; SILVA, Luís Cláudio Nascimento da; 061.482.494-05; http://lattes.cnpq.br/6016850820500623; SILVA, Luís Cláudio Nascimento da; 061.482.494-05; http://lattes.cnpq.br/6016850820500623; MIRANDA, Rita de Cássia Mendonça de; http://lattes.cnpq.br/1952235749528138; MONTEIRO, Cristina de Andrade; http://lattes.cnpq.br/2495926580105868; SANTOS, Juliana Ribeiro dos; ALBUQUERQUE, Priscilla Barbosa SallesSevere injuries result in serious injury and or loss of function in the affected areas and treatment has challenged health professionals because of its complexity, especially in patients with chronic diseases (eg.: diabetes), and the presence of pathogens such as Staphylococcus aureus and Pseudomonas aeruginosa. Given this, the development of new wound healing therapies requires immediate attention. Several preparations obtained from the Asteraceae family have been found to show good efficacy when evaluated in complicated wound clinical trials, including venous leg ulcers and foot ulcers of diabetic patients. Cinnamaldehyde (CNM) has broad spectrum in vitro antimicrobial action related to membrane cell wall instability and changes in energy metabolism. CNM, when administered to Staphylococcus aureus infected skin wounds, which is considered to be the most common pathogenic microorganism in skin wounds, improves the healing process of pathogen-infected skin lesions, possibly due to its antimicrobial action. anti-inflammatory, possibly due to its anti-microbial and anti-inflammatory action. Since it reduced both antimicrobial load and production of inflammatory cytokines such as TNF-α and IL-6 and accelerated the healing process.Item Avaliação da qualidade ambiental do golfão maranhense por meio de variáveis biológicas, químicas e físico-químicas(Universidade Federal do Maranhão, 2019-10-10) SILVA, Marcelo Henrique Lopes; BASSO, Marianna Jorge; http://lattes.cnpq.br/1185970315739551; NUNES, Jorge Luiz Silva; http://lattes.cnpq.br/1899258151972278; NUNES, Jorge Luiz Silva; http://lattes.cnpq.br/1899258151972278; PIORSKI , Nivaldo Magalhães; http://lattes.cnpq.br/7220575466585169; WOSNICK , Natascha; http://lattes.cnpq.br/1871674868620853; BARRETO , Larissa Nascimento; http://lattes.cnpq.br/1295307492454506; SANTOS, Débora Martins Silva; http://lattes.cnpq.br/3703951344689165The reduction of aquatic biodiversity is among the main changes that occur in the natural environment, as a consequence of the disruption of the physical, chemical and biological environment, resulting in loss of quality and difficulty in maintaining environmental integrity. Studies that integrate different thematic areas are necessary to formulate consistent diagnoses that faithfully portray the status of the environmental quality of aquatic ecosystems, providing the scientific basis for management actions of these systems. In this perspective, the present work aims to evaluate the environmental quality of Golfão Maranhense using nutrient dynamics, physicochemical factors and fish community as environmental indicators. Water samples were collected from the surface using a Van Dorn water sampler, where the following hydrochemical variables were analyzed: water transparency (m), temperature (° C), salinity, conductivity (mS cm-¹), total dissolved solids. (TDS, g L-1), pH, dissolved oxygen (mg L-1), turbidity (NTU), total suspended solids (TSS) and dissolved nutrients (phosphate, nitrite and silicate). The relationships between these variables and the seasonality of the region, rainy season (January to June) and dry season (July to December), as well as the influence on the composition of fish communities were also evaluated. Fish were collected from 11 estuaries located in São Marcos, São José and Arraial bays. Samplings were performed with a trawnet in three replicates for each collection point. The results showed that the spatial and temporal variability of the physicochemical variables analyzed in this study is associated with the local dynamics governed by river flow, tidal movements, currents and meteorological events. Fluvial transportation of Maranhão State rivers and other freshwater sources in the Amazon region are apparently the main contributors responsible for maintaining nutrient availability in the Maranhão continental shelf. The composition of the Ichthyofauna of St. Mark's Bay was represented by a total of 56 species, distributed in 15 orders and 29 families. Seasonal evaluation of fish assemblage revealed no significant difference. However, there was a difference between the capture sites where Shannon abundance, biomass and diversity differed. The NMDS analysis (Multidimensional Scaling Analysis) and the ANOSIM (Similarity Analysis) test between months and between sampling sites, based on species composition, revealed a seasonal differentiation associated with rainy and drought months, as well as a spatial differentiation related to depth and hydrodynamic gradient resulting from the greater distance from the mangrove areas. Estimates of the weight-length ratio parameters consisted of a total of 2,888 specimens analyzed. The values of parameter b showed a predominance of positive allometric growth type, similar to other studies conducted in the region. Toxicological analysis did not show results that indicate high degree of bioaccumulation of trace metals in the ichthyofaunada of the region, but individual samples with levels above the established limits were verified, indicating that there is some degree of contamination in the region. The application of environmental quality parameters has proved to be a useful tool for decision-making, environmental planning and environmental quality assessment, checking for changing trends in aquatic ecosystems.Item RELEVÂNCIA DO CANAL IÔNICO TRPV1 NO DESENVOLVIMENTO DA MALÁRIA CEREBRAL.(Universidade Federal do Maranhão, 2019-07-05) PEREIRA, Domingos Magno Santos; MARINHO, Claudio Romero Farias; 089.861.798-73; http://lattes.cnpq.br/1074133203981424; FERNANDES, Elizabeth Soares; 033.401.406-93; http://lattes.cnpq.br/9631573633970523; FERNANDES, Elizabeth Soares; 033.401.406-93; http://lattes.cnpq.br/9631573633970523; FERREIRA, Juliano; LIBERIO, Rosane Nassar Meireles Guerra; http://lattes.cnpq.br/2316192786452127; PAES, Antonio Marcus de Andrade; http://lattes.cnpq.br/2310501964710274; MONTEIRO, Andrea de Souza; http://lattes.cnpq.br/9268996030726117Malaria is an infectious, systemic and parasitic disease of global importance, with a high morbidity and mortality rate. Severe malaria is a neurological complication associated with brain inflammation which can lead to death or cause neurological sequelae in surviving patients. The patient's innate immune response plays a decisive role in host defense and also in the pathogenesis of cerebral malaria, since the presence of infected erythrocytes sequestered in the endothelium of the cerebral microcirculation triggers the mechanisms of the oxidative and nitrosative stress, with excessive production of reactive oxygen (ROS) and nitrogen (RNS) species, molecules related to lipid peroxidation, causing damage not only to the parasite, but also to endothelial cells and to the integrity of the blood-brain barrier, exposing then, the central nervous system to Plasmodium facliparum (in humans) and P. berghei ANKA (in rodents). Among the several changes occurring in the host in cerebral malaria, oxidative/nitrosative stress is essential for killing the parasite and signaling the immune response; in addition, the mechanism of action of several antimalarial drugs currently available targets the increase of oxidative stress, reducing parasitemia and controlling infection. In the human organism, oxidative/nitrosative stress is regulated by a group of cell membrane receptors, such as TRPV1. It was recently shown that the transient potential receptor vaniloid 1 (TRPV1), an oxidative stress sensor, modulates the peripheral immune response to malaria; however, little is known of its relevance to the cerebral changes caused in the sereve form of the disease. Therefore, the relevance of the TRPV1 in the development of cerebral malaria induced by Plasmodium berghei ANKA (1x106 infected RBCs per animal, i.p) in wild type (WT) and knockout (TRPV1KO) mice, were investigated. In another set of experiments, the use of the selective TRPV1 antagonist, SB366791, was also studied. The results show that P. berghei ANKA-induced infection significantly reduces TRPV1 expression in brain tissue. Furthermore, TRPV1 KO animals were protected against morbidity and mortality caused by cerebral malaria by attenuating the signs and symptoms of the disease as well as mortality without affecting the parasitaemia. This response was associated with reduced cerebral edema formation and modulation of gene expression of blood-brain barrier integrity markers (claudin-5 and JAM-A), as well as increased production of reactive species generated by tissue and plasma oxidative stress; and reduction in the production of systemic and cerebral cytokines. Treatment with SB366791 initiated after induction of the cerebral malaria promoted enhanced TRPV1 gene expression in the brain and increased mouse survival. Our data from the present thesis indicate for the first time that the TRPV1 ion channel contributes to the development and prognosis of cerebral malaria by modulating cerebral inflammation, therefore, it may be suggested as a therapeutic target for the treatment of Plasmodium falciparum-infected patients.Item ESTUDO DE FÁRMACOS ANTICANCERÍGENOS NITROSUREIAS E AVALIAÇÃO IN SITU DE SUAS INTERAÇÕES COM DNA UTILIZANDO BIOSSENSORES ELETROQUÍMICOS DE DNA.(Universidade Federal do Maranhão, 2019-07-01) CARVALHO, Paulina Andréa Viana de; LOPES, Ilanna Campelo; 840.689.733-34; http://lattes.cnpq.br/9543261878791947; TANAKA, Auro Atsushi; 005.482.048-02; http://lattes.cnpq.br/1460765270568999; TANAKA, Auro Atsushi; 005.482.048-02; http://lattes.cnpq.br/1460765270568999; YAMANAKA, Hideko; http://lattes.cnpq.br/1923726000036625; NUNES, Gilvanda Silva; http://lattes.cnpq.br/5833210771020427; SANTANA, Sirlane Aparecida Abreu; http://lattes.cnpq.br/1052349578152491; LIMA, Roberto Batista de; http://lattes.cnpq.br/4982744838486744Lomustine (CCNU) and carmustine (BCNU) belong to the class of nitrosureas, which are nnitro compounds capable of alkylate DNA structures. They are lipophilic and can go through the blood-brain barrier, and due to these characteristics, they are used in the treatment of brain tumors and other neoplasms. To understand the interaction mechanisms of these compounds with DNA, voltammetric techniques and DNA-electrochemical biosensors were used. Firstly, the study of the electrochemical behavior of CCNU and BCNU and their degradation in aqueous solution on a glassy carbon electrode (GCE) was performed using voltammetric techniques. From this study, the in situ interaction of both with deoxyribonucleic acid (dsDNA) was investigated in incubated solutions, using dsDNA-electrochemical biosensors and the comet test. Both CCNU and BCNU underwent electrochemical reduction in two irreversible redox processes, diffusion-controlled, pH dependent involving the transfer of two electrons and one proton, each. There was no formation of electroactive reduction products. At pH ≥ 10, the peak potential for the two processes tends to be pH independent by involving only electrons. A reduction mechanism of the CCNU and BCNU in neutral media was proposed. In addition, both antineoplastics underwent spontaneous degradation in aqueous solution over the incubation time, without the formation of electroactive degradation products. The CCNU and BCNU degradation process was more evident in a basic medium. The in situ interaction of CCNU and BCNU with dsDNA showed these pro-drugs interacted with DNA initially causing the condensation of the double helix strands and then the unwinding of these strands. Moreover, free guanine (Gua) was released and oxidative damage caused to dsDNA by both compounds were observed, since 8-oxoguanine (8-oxoGua) and 2,8-dihydroxyadenine (2,8-DHA) were detected. These results were confirmed by the poly (dA)- and poly [dG]-electrochemical biosensors, which demonstrated the oxidative damage caused by dsDNA in both bases, guanine and adenine, by the CCNU degradation product(s). BCNU caused oxidative damage only in the guanine. The comet assay indicated breaks in the single strand of DNA, corroborating with the studies performed by differential pulse voltammetry.Item Levantamento de indicadores de qualidade do solo como base para a construção de um índice de sustentabilidade agrícola(Universidade Federal do Maranhão, 2019-06-25) FEITOSA , Ana Luiza Privado Martins; AGUIAR, Alana das Chagas Ferreira; 705568063-87; http://lattes.cnpq.br/7656587511436822; AGUIAR, Alana das Chagas Ferreira; 705568063-87; http://lattes.cnpq.br/7656587511436822; CASTRO, Antônio Carlos Leal de; http://lattes.cnpq.br/9450410023114396; SILVA, Fabrício Brito; http://lattes.cnpq.br/3322637911743278; BEZERRA, Denilson da Silva; http://lattes.cnpq.br/6162113647472848; SILVA, Gutierres Nelson; http://lattes.cnpq.br/2968968667886414Soil attributes can be modified because management practices and crops, changing edaphic quality and negatively affecting the sustainability of agricultural activity. Since the concept of quality is subjective, the construction of quantitative assessment systems based on indicators is very important. This work is based on the hypothesis that it is possible to select soil quality indicators under different fertilization regimes, as a basis for the elaboration of an agricultural sustainability index. The present study aimed to propose soil quality indicators under different fertilization regimes to compose an Agricultural Sustainability Index (ASI). The experimental area is located in the municipality of Brejo, state of Maranhão, Brazil. Two experiments were carried out with alley crop using legume, of which the pruning was used in the treatments with legume. One of experiments corresponded to Leucena (Leucaena leucocephala), and the other to Gliricidia (Gliricidia sepium). The area between the legume lines was divided into plots in a randomized block design. The area with Leucaena was divided in 24 plots, with 4 replicates and 6 treatments, which were nitrogen (N), leucaena (L), nitrogen + leucaena (N + L); humic acid + leucaena (HA + L); humic acid + nitrogen (HA + N) and humic acid + nitrogen + leucaena (HA + N + L). The area with Gliricidia was divided into 32 plots with 4 replicates and 8 treatments, which were potassium (K), gliricidia (G), humic acid (HA), humic acid + potassium (HA + K), potassium (K + G), humic acid + gliricidia (HA + G), humic acid + potassium + gliricidia (HA + K + G) and uncovered soil (US). Each plot was cultivated with maize (Zea mays L.) to obtain grains yield. Biological and chemical attributes were used in this research. Soil fauna was used as biological indicator and was collected through pitfall traps. The total abundance, dominance, richness, Shannon-Wiener diversity index and Pielou equitability index of edaphic fauna were determined. Soil samples were collected at depths of 0–5 cm, 5–10 cm and 10–20 cm to obtain chemical data. Potential acidity, pH, soil organic carbon (SOC), available phosphorus, exchangeable potassium, calcium and magnesium, cation exchange capacity (CEC), sum of base cation (SBC) and base saturation (BS) were determined. Principal component analyzes (PCA) were performed to correlate soil biological and chemical attributes with maize grains yield. An ASI was suggested based on the indicators used in this study, whose weights were obtained on the PCAs results. This research indicates that biological and chemical attributes of soil quality are sensitive to changes in soil fertilization regimes and that these attributes can be associated with maize grains yield and can be used as indicators of soil quality in the composition of an Agricultural Sustainability Index.Item Estudo dos mecanismos associados aos efeitos da tioredoxina derivada de Escherichia coli na sepse(Universidade Federal do Maranhão, 2018-11-22) MENDES, Saulo José Figueiredo; SILVA, Luís Cláudio Nascimento da; 061482494-05; http://lattes.cnpq.br/6016850820500623; FERNANDES, Elizabeth Soares; 033401406-93; http://lattes.cnpq.br/9631573633970523; FERNANDES, Elizabeth Soares; 033401406-93; http://lattes.cnpq.br/9631573633970523Thioredoxin (Trx) is a redox protein produced by all species, from bacteria to humans. It role as an antioxidant molecule is well known; however, its regulatory actions in the host are less understood. Evidences suggest this protein may be part of the bacteria anti-virulence strategy to evade the host immune system. Reduced human Trx activates transient receptor potential canonical 5 (TRPC5) in inflammation, but there is no evidence of whether these receptors mediate bacterial Trx effects in the host. Importantly, TRPC5 can form functional complexes with other subunits such as TRPC4. Herein, E. coli-derived Trx induced mortality in lipopolysaccharide (LPS)-injected mice, accompanied by reduction of leukocyte accumulation, regulation of cytokine release into the peritoneum, and impairment of peritoneal macrophage-mediated phagocytosis. Dual TRPC4/TRPC5 blockade by ML204 increased mortality and hypothermia in Trx-treated LPS mice, but preserved macrophage´s ability to phagocytose. TRPC5 deletion did not alter body temperature, but promoted additional accumulation of peritoneal leukocytes and inflammatory mediator release in Trx-administered LPS mice. Trx diminished macrophage-mediated phagocytosis in wild type but not TRPC5 knockout animals. TRPC5 ablation did not affect LPS-induced responses. However, ML204 caused mortality associated with exacerbated hypothermia and decreased peritoneal leukocyte numbers and cytokines in LPS-injected mice. These results suggest that bacterial Trx effects under LPS stimuli are mediated by TRPC4 and TRPC5, shedding light on the additional mechanisms of bacterial virulence and on the pathophysiological roles of these recepItem Influência da precipitação e hidrodinâmica na biodiversidade ictiofaunística e entomológica no baixo curso de rio estuarino pré-amazônico(Universidade Federal do Maranhão, 2017-08-28) SANTOS, Paula Verônica Campos Jorge; CASTRO, Antonio Carlos Leal de; 064868003-72; http://lattes.cnpq.br/9450410023114396; REBÊLO, José Manuel Macário; 149280863-68; http://lattes.cnpq.br/1026308157852394; CUNHA, Alan Cavalcanti da; http://lattes.cnpq.br/2181817533284030; SILVA, Edson Vicente da; http://lattes.cnpq.br/3354228537186786; SOARES, Leonardo Silva; http://lattes.cnpq.br/5352983119262178; BEZERRA, Denilson da Silva; http://lattes.cnpq.br/6162113647472848Introduction. Modifications of the hydrological and physical characteristics can alter the biodiversity of a region, since each group of individuals tolerates a certain range of modification of these attributes. Generally the region of the low course of the rivers that flow in the sea are subject to variations of cycles of tides of the ocean, configuring a region of intense hydrodynamics, imposing still more limitation to the aquatic biota. Goal. The objective of this work was to know the hydrological behavior and the influence of the low tide cycles of the Itapecuru river and the spatial and temporal effects on the composition of the aquatic biota (fish communities and aquatic insects). Methodology. To achieve this objective, biological data were collected at three different points located between the municipalities of Santa Rita and Rosario. The fish group was captured from May 2012 to August 2014, and the group of aquatic insects was collected from February to November 2014, every three months. Other on-site campaigns were carried out to obtain current, flow, tidal influence and salinity data. Results. The results suggest that the low course of the Itapecuru river presents great tidal variations in the flow dynamics, which directly influences the increase and decrease of the river quota and the direction and speed of the current. However, the influence of the tide is only dynamic, and there is still the advance of salt tide over the area. For the fish community, multivariate analysis using the non-metric multidimensional scaling technique (MDS) signaled the formation of two seasonal groups, with abundance and richness being the main responsible for similarity. The observed patterns did not indicate changes in the values of diversity, equitability and wealth. The ABC curve characterized the section investigated as an environment under natural conditions. However, based on field assessments, a trend towards degradation scenarios for this group was observed. This trend is associated with impacts on riparian forest, as a result of the occupation of the banks by the riverside communities, and also due to the constant release of sewage, especially in the stretches closer to the municipality of Rosario. In relation to the community of aquatic insects, a greater abundance was verified in the rainy period. Spatially, the point of capture with the highest number of individuals was the intermediate point between the most downstream and the most upstream, where the outflows at the beginning of the rainy season tend to be higher, a determining characteristic for species fixation. Comparisons of the diversity of Shannon-Winner indicated that there is no significant difference between the points, although the highest value was observed in point 3, located in the municipality of Rosario, more downstream subject to the more intense dynamics of the rise and fall of the tide. Seasonally the greatest diversity occurs in the rainy season, with the occurrence of 6 orders and more class collembola. Of the 27 families found in the study, 17 were classified as constants, being the chironomidae family of the dipterous order present in 100% of the samplings.Item Epidemiologia da leishmaniose americana da região do Parque Nacional dos Lençóis Maranhenses: enfoque na identificação das espécies de leishmânias e na capacidade vetorial dos flebotomíneos(Universidade Federal do Maranhão, 2016-06-24) Fonteles, Raquel Silva; REBÊLO, José Manuel Macário; 149.280.863-68Leishmaniasis are a group of neglected infectious and parasitic diseases, with major repercussions at global and national level. In the State of Maranhao, both the American Cutaneous Leishmaniasis (LTA) and the American Visceral Leishmaniasis (LVA) are endemic and have great prominence at the national scene. Within the state territory, one of the leading regions is the Lençóis Maranhenses National Park - PNLM, whose surroundings have undergone environmental and ecological damage caused by man, resulting from direct and indirect tourism activities. As a result of this process every year are recorded cases, mostly LTA ones. Goals. Facing such reality, this study aimed: to define the epidemiological profile of the LTA between the years 2007 and 2013, taking into account demographic (age and gender), occupational and chronological features of the affected populations (reported cases); to demonstrate through a cartographic tool, a survey of the timeline distribution of cases of LTA; and an interactive map to determine the risk rate for acquisition of LT. It has been also proposed to study the transmission cycle of the disease, based on the identification of species of sandflies, their sources of blood and their Leishmania genus parasites, and additionally determining vector capacity of Lu. Whitmani toward Le. Braziliensis and Le. Amazonians. Methodology. The county of Barreirinhas was selected for this study because it is the main gateway to PNLM. In short, investigation of LTA cases was carried out in SINAN files, comprising all neighborhoods of the county (158), through the cycle 2007-2013, and sandflies collections were held in 62 of these communities. The species were identified taxonomically and females analyzed at the molecular level to research for natural infection by Leishmania, along with the animals that served as a food source. Results. 458 positive cases of LTA were reported between the years 2007 and 2013, predominantly in men from rural areas and farmers. The cases were concentrated in the south central area of the county, all year round. There was some geographic expansion with the emergence of new outbreaks, however, it was observed the persistence of the former areas of occurrence of the disease. As for the risk rates, villages Sítio Barra, Engenho and Manoelzinho were those who were positive for all variables. On the other side, the communities Quebra, Santa Rosa and Fumaça, presented less risk, since almost all the variables studied were negative for these locations. As for the sandflies, 9,853 specimens of 18 species have been collected, all present in extra-domicile (forest) and only 12 occurring in peri-domicile areas. The incidence was higher in areas surrounding dwellings (56.2%) than in extra-domicile environment (43.8%) and females predominated (51.4%) over males (48.6%). The dominant species were Lu. whitmani (53.83%), Lu. longipalpis (25.60%), Lu. Lenti (11.69%), Lu. evandroi (5.50%) and Lu. flaviscutellata (0.87%). Natural infections due to Le. infantum, were found in females captured in peri-domicile in five villages and extra-domicile in other two. The species Lu. longipalpis, vector of Le. Infantum, indicated a positivity rate of 3.7% for this species. While species not considered insect vector of this leishmania, such as Lu. Lenti and Lu. Whitmani, even so presented infection rates of 0.6% and 0.9%, respectively. Rates of natural infection due to Le. braziliensis, were detected in peri-domicile in two locations; while in Lu. Whitmani, considered the vector of this Leishmania species, rate of 0.3% was found. The rate of infection due to Le. amazonensis was 8% for Lu. Flaviscutelata, captured in peri-domicile in two villages and extra-domicile in just one. Lu. whitmani was able to get infected with Le. Braziliensis and Le. Amazonians. Concerning food source hosts, the following were identified: equines (9.0%), human (1.4%), canine (27.4%), rodent (3.3%), fowl (20.9%) and hogs (37.9%). Conclusion. All elements of the epidemiological chain of Leishmaniasis were present within the area of study, both in peri-domicile and extra-domicile areas, which explains the endemic state of the disease in the region.Item Uso de indicadores químicos na avaliação da qualidade do Argissolo vermelho amarelo distrocoeso em um sistema de cultivo em aleias(Universidade Federal do Maranhão, 2016-06-27) Amorim, Andreia Pereira; Moura, Emanoel Gomes de; 100.416.131-04; AGUIAR, Alana das Chagas Ferreira; 705.568.063-87The use of chemical indicators used to evaluate soil quality in a growing alley cropping can identify the causes of land degradation in agricultural systems of the Amazon, the conversion of forest to these agricultural systems, incompatible with soil and climatic conditions of this region. This degradation is considered one of the greatest threats to the rainforest due to depletion of phosphorus (P), the decline in soil organic matter (SOM) and the loss of basic cations. two kinds of high quality waste were used: (Leucaena leucocephala and Gliricidia sepium), and two species of low quality waste (Clitoria fairchildiana and Acacia mangium). The 1600m2 area was sampled for carrying out chemical analysis and fractionation of organic matter and soil phosphorus. The SOM was separated by density fractionation soil. Fractionation of P in soil was carried out with extraction solutions. The experimental design was randomized blocks: leucena + sombrero (L + S); leucena + acacia (L + A); gliricidia + acacia (G + A); gliricidia + sombrero (G + S) and control treatment without pulses with five treatments and eight repetitions. The corn was used as test culture. Legumes were pruned to 50 cm of soil waste materials were added to the surface and then the corn was sown. All soil samples of the experiment in alleys had low pH values. The results show statistical differences between treatments when to soil organic matter (SOM). The highest levels were found in the treatment leucena + sombrero (L + S), but did not influence the carbon stock of Fractions Take Free (FLL), Intra-aggregate fractions (FLI) and MOP MOS, which showed no statistical difference. Therefore, in accordance cutting alleys, most of the P found in inorganic form, and was also found in fractions moderately labile and difficult. The results indicate that the fractions of P and organic matter are important indicators to evaluate changes in the degree of land degradation in the humid tropics. These results also indicate that the intensive and continuous use of annual crops in soils of the regions of the Amazon without any conservation practice can be considered as a high risk to the sustainability of agricultural systems, mainly because of increased active and potential acidity, reducing labile organic matter and depletion of organic P pools, leading to soil degradation. Soil fertility, physical properties and available P are responsible for the variability of soil degradation. Considering that small farmers are responsible for 70% of agricultural production in the country, the sustainable management of these soils, usually of low fertility by agroecological alley cropping of legumes is an alternative to agriculture as socioeconomic and environmental benefits.