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"Souza, L. I. O."
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Phytochemical screening and in vitro antibacterial, antifungal, antioxidant and antitumor activities of the red propolis Alagoas
by
Fonseca, S. A.
,
Silva, F. R. G.
,
Souza, L. I. O.
in
Allelochemicals
,
Alternative medicine
,
Anticancer properties
2019
Abstract The study aimed to evaluate the antimicrobial activity, antioxidant, toxicity and phytochemical screening of the Red Propolis Alagoas. Antimicrobial activity was evaluated by disk diffusion method. Determination of antioxidant activity was performed using the DPPH assay (1.1-diphenyl-2-picrylhydrazyl), FTC (ferric thiocyanate) and determination of phenolic compounds by Follin method. Toxicity was performed by the method of Artemia salina and cytotoxicity by MTT method. The phytochemical screening for the detection of allelochemicals was performed. The ethanol extract of propolis of Alagoas showed significant results for antimicrobial activity, and inhibitory activity for Staphylococcus aureus and Candida krusei. The antioxidant activity of the FTC method was 80% to 108.3% hydrogen peroxide kidnapping, the DPPH method showed an EC50 3.97 mg/mL, the content of total phenolic compounds was determined by calibration curve gallic acid, resulting from 0.0005 mg/100 g of gallic acid equivalent. The extract was non-toxic by A. salina method. The propolis extract showed high activity with a higher percentage than 75% inhibition of tumor cells OVCAR-8, SF-295 and HCT116. Chemical constituents were observed as flavonones, xanthones, flavonols, and Chalcones Auronas, Catechins and leucoanthocyanidins. It is concluded that the extract can be tested is considered a potential source of bioactive metabolites. Resumo O trabalho teve como objetivo avaliar a atividade antimicrobiana, antioxidante, a toxicidade e a prospecção fitoquímica da Própolis Vermelha de Alagoas. A atividade antimicrobiana foi avaliada pelo método de difusão em disco. A determinação do potencial antioxidante foi realizada utilizando o método de DPPH (1,1-difenil-2-picrilhidrazil), FTC (Tiocianato Férrico) e determinação de compostos fenólicos pelo método de Follin. A toxicidade foi realizada pelo método de Artemia salina e a citotoxicidade pelo método do MTT. Foi realizada a prospecção fitoquímica para a pesquisa de aleloquímicos. O extrato etanólico da própolis vermelha de Alagoas apresentou resultados significantes para atividade antimicrobiana, tendo a atividade inibitória para Staphylococcus aureus e Candida krusei. Quanto a atividade antioxidante o método de FTC teve 80% a 108,3% de sequestro de peróxido de hidrogênio, o método de DPPH apresentou um CE50 de 3,97 μg/mL, o teor de compostos fenólicos totais foi determinado mediante curva de calibração do ácido gálico, tendo resultado de 0,0005 mg/100 g equivalente de ácido gálico. O extrato foi atóxico pelo método de A. salina. O extrato da própolis mostrou elevada atividade com percentual de inibição maior que 75% sobre células tumorais OVCAR-8, SF-295 e HCT116. Foram observados constituintes químicos como flavononas, xantonas, flavonóis, Chalconas e Auronas, Catequinas e Leucoantocianidinas. Conclui-se que o extrato testado pode ser considerado é uma fonte potencial de metabólitos bioativos.
Journal Article
Optimization of genomic DNA and total RNA extraction protocols from microlepidopterans for high-fidelity long-read sequencing
BackgroundMicrolepidoptera, for the most part, are important agricultural pests capable of causing economic losses in different global crops, highlighting the need for biotechnological control strategies. They are small species, with a cryptic behaviors and high chitin content in their structure. Furthermore, they have eating habits that can make it difficult to extract high-quality gDNA and RNA. The limited number of existing protocols to obtain high mass nucleic acids from smaller insects render difficult to obtain elevated purity and integrity standards. We present straightforward and reproducible protocol modifications for extracting DNA and RNA for PacBio and Illumina sequencing from Leucoptera coffeella, also validated in Plutella xylostella and Tuta absoluta.MethodsGenomic DNA was extracted from a pool of 20 L. coffeella pupae using a modified protocol based on a commercial extraction kit, performed over two days. Key optimizations included cell lysis with CTL buffer, use of wide-bore pipette tips, extended and agitated incubation during protein digestion, and elution at room temperature with a reduced buffer volume. Total RNA was extracted from all seven developmental stages of L. coffeella in 2 h and 35 min. In addition to standard protocol steps, an extra purification step using a commercial kit was included to improve RNA quality.DiscussionCompared to other extraction methods, these protocols showed higher degree purity and concentration. The extracted samples presented concentrations, absorbance and integrity relationships recommended and validated by HiFi sequencing. The extraction of nucleic acids from microlepidopterans may present several challenges, such as the small size and fragility of the samples and contamination by microorganisms, which can affect the quality of the genetic material obtained. The optimization described here provides significant improvements for obtaining gDNA and RNA from L. coffeella and can be applied to other insect species, particularly microlepidoptera, as here validated in P. xylostella and T. absoluta. Essential for genomic and transcriptomic studies and also enhance various molecular techniques, such as PCR, qPCR, molecular markers, and others.
Journal Article
Introduction: Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5)
2016
The Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5) Experiment was carried out in the environs of Manaus, Brazil, in the central region of the Amazon basin for 2 years from 1 January 2014 through 31 December 2015. The experiment focused on the complex interactions among vegetation, atmospheric chemistry, and aerosol production on the one hand and their connections to aerosols, clouds, and precipitation on the other. The objective was to understand and quantify these linked processes, first under natural conditions to obtain a baseline and second when altered by the effects of human activities. To this end, the pollution plume from the Manaus metropolis, superimposed on the background conditions of the central Amazon basin, served as a natural laboratory. The present paper, as the introduction to the special issue of GoAmazon2014/5, presents the context and motivation of the GoAmazon2014/5 Experiment. The nine research sites, including the characteristics and instrumentation of each site, are presented. The sites range from time point zero (T0) upwind of the pollution, to T1 in the midst of the pollution, to T2 just downwind of the pollution, to T3 furthest downwind of the pollution (70 km). In addition to the ground sites, a low-altitude G-159 Gulfstream I (G-1) observed the atmospheric boundary layer and low clouds, and a high-altitude Gulfstream G550 (HALO) operated in the free troposphere. During the 2-year experiment, two Intensive Operating Periods (IOP1 and IOP2) also took place that included additional specialized research instrumentation at the ground sites as well as flights of the two aircraft. GoAmazon2014/5 IOP1 was carried out from 1 February to 31 March 2014 in the wet season. GoAmazon2014/5 IOP2 was conducted from 15 August to 15 October 2014 in the dry season. The G-1 aircraft flew during both IOP1 and IOP2, and the HALO aircraft flew during IOP2. In the context of the Amazon basin, the two IOPs also correspond to the clean and biomass burning seasons, respectively. The Manaus plume is present year-round, and it is transported by prevailing northeasterly and easterly winds in the wet and dry seasons, respectively. This introduction also organizes information relevant to many papers in the special issue. Information is provided on the vehicle fleet, power plants, and industrial activities of Manaus. The mesoscale and synoptic meteorologies relevant to the two IOPs are presented. Regional and long-range transport of emissions during the two IOPs is discussed based on satellite observations across South America and Africa. Fire locations throughout the airshed are detailed. In conjunction with the context and motivation of GoAmazon2014/5 as presented in this introduction, research articles including thematic overview articles are anticipated in this special issue to describe the detailed results and findings of the GoAmazon2014/5 Experiment.
Journal Article
Fungi from Anopheles darlingi Root, 1926, larval breeding sites in the Brazilian Amazon
by
Souza, Afonso Duarte Leão de
,
Souza, Antonia Queiroz Lima de
,
Katak, Ricardo de Melo
in
Animals
,
Anopheles - genetics
,
Anopheles - microbiology
2024
The fungi present in the breeding waters of mosquitoes have been scarcely investigated. This work explored the diversity of cultivable fungi present in the breeding sites of the South American malaria vector mosquito Anopheles darlingi . Water samples were collected from four sites located in the municipalities of Coari and São Gabriel da Cachoeira and four different culture media were used for the isolation of fungi. Two-hundred-and-six fungal strains were isolated and morphologically similar fungi were grouped into 30 morphotypes. Their taxonomic identities were assigned by macro and microscopic observations and sequencing of rDNA internal transcribed spacers ( ITS1-5 . 8S-ITS2 ). Representatives of 26 morphotypes were identified at the genus level, one only at the family level, and three were not identified. The identified morphotypes belong to the phyla, Ascomycota (80.6%), Basidiomycota (11.7%), and Mucoromycota (2.4%), distributed in five classes, ten orders, 25 families, and 26 genera. This study fills a considerable knowledge gap about the fungi present in the breeding sites of An . darlingi mosquitoes.
Journal Article
Astrocyte biomarker signatures of amyloid-β and tau pathologies in Alzheimer’s disease
by
Gauthier, Serge
,
Karikari, Thomas K
,
Rocha, Andréia
in
Aging
,
Alzheimer's disease
,
Astrocytes
2022
Astrocytes can adopt multiple molecular phenotypes in the brain of Alzheimer’s disease (AD) patients. Here, we studied the associations of cerebrospinal fluid (CSF) glial fibrillary acidic protein (GFAP) and chitinase-3-like protein 1 (YKL-40) levels with brain amyloid-β (Aβ) and tau pathologies. We assessed 121 individuals across the aging and AD clinical spectrum with positron emission tomography (PET) brain imaging for Aβ ([18F]AZD4694) and tau ([18F]MK-6240), as well as CSF GFAP and YKL-40 measures. We observed that higher CSF GFAP levels were associated with elevated Aβ-PET but not tau-PET load. By contrast, higher CSF YKL-40 levels were associated with elevated tau-PET but not Aβ-PET burden. Structural equation modeling revealed that CSF GFAP and YKL-40 mediate the effects of Aβ and tau, respectively, on hippocampal atrophy, which was further associated with cognitive impairment. Our results suggest the existence of distinct astrocyte biomarker signatures in response to brain Aβ and tau accumulation, which may contribute to our understanding of the complex link between reactive astrogliosis heterogeneity and AD progression.
Journal Article
Optimized and Functionalized Carvacrol-Loaded Nanostructured Lipid Carriers for Enhanced Cytotoxicity in Breast Cancer Cells
by
Silva, Anauara L.
,
Souza, Ramon R. M.
,
Silva, Marcelo S.
in
Albumin
,
Breast cancer
,
Cancer therapies
2025
Background/Objectives: Carvacrol, a monoterpenoid phenol found in essential oils, exhibits many biological activities, including anticancer properties through mechanisms such as induction of apoptosis. These properties can be enhanced if encapsulated within nanoparticles. This study focuses on producing functionalized carvacrol-loaded nanostructured lipid carriers (NLCs) applied to the treatment of breast cancer. Methods: NLCs were produced by hot emulsification with the sonication method and optimized by the Box–Behnken design, considering Precirol® (1, 4, 7%), carvacrol (1, 5, 9%), and Tween® (0.1, 0.5, 0.9%) as independent variables. Results: The optimized NLC containing 2% carvacrol had a particle size of 111 ± 2 nm, PdI of 0.26 ± 0.01, and zeta potential of −24 ± 0.8 mV. The solid lipid (Precirol®) was the variable that most influenced particle size. NLCs were functionalized with Pluronic® F68, cholesterol, chitosan, and polyethylene glycol (0.05–0.2%), with oNLC-Chol presenting the most promising results, with no significant increase in particle size (±12 nm) and high encapsulation efficiency (98%). Infrared spectra confirm effective carvacrol encapsulation, and stability tests showed no significant physicochemical changes for 120 days of storage at 4 °C. When incubated with albumin (5 mg/mL), NLCs showed overall good stability over 24 h, except for oNLC-Chol, which increased slightly in size after 24 h. In addition, oNLC increased the cytotoxic effect of carvacrol by 12-fold, resulting in an IC50 of 7 ± 1 μg/mL. Conclusions: Therefore, it was possible to produce stable, homogeneous NLCs with nanometric sizes containing 2% carvacrol that displayed improved anticancer efficacy, indicating their potential as a delivery system.
Journal Article
Estimated SARS-CoV-2 Infection and Seroprevalence in Firefighters from a Northeastern Brazilian State: A Cross-Sectional Study
by
Heimfarth, Luana
,
Matos, Igor L. S.
,
Oliveira, Brenda M.
in
Antibodies
,
Antibodies, Viral - blood
,
Asymptomatic
2021
The new coronavirus has been affecting health worldwide and essential service workers are continually exposed to this infectious agent, increasing the chance of infection and the development of the disease. Thus, this study aimed to estimate the frequency of infection and seroprevalence for SARS-CoV-2 in military firefighters in a city in Northeastern Brazil in January 2021. An observational cross-sectional study was carried out with 123 firefighters who answered a brief questionnaire to collect socio-epidemiological data and underwent RT-PCR and immunofluorescence test (IgM and IgG). The results found reveal a positive seroprevalence, with a high rate of infection in this class of workers, since they are essential service professionals who are exposed to risk due to their working hours, in addition to sharing some spaces and work materials. Besides, there were significant associations between positivity for IgG and IgM, as well as for positive RT-PCR prior to the study and the presence of IgG, with odd ratios of 3.04 and 4.9, respectively. These findings reinforce the need for immunization in this category, whose line of service hinders the adoption of distancing measures, since in many situations physical contact is inevitable.
Journal Article
Fine-tuning of Arabidopsis thaliana response to endophytic colonization by Gluconacetobacter diazotrophicus PAL5 revealed by transcriptomic analysis
by
SOUZA, A. L. S. R. DE
,
VESPOLI, L. DE S
,
SOARES, F. S
in
Agricultural production
,
Arabidopsis thaliana
,
Bacteria
2024
Here, we used the RNA-seq approach to understand better the effect of G. diazotrophicus PAL5 on the transcriptome of shoot and root tissues of Arabidopsis thaliana. G. diazotrophicus colonized A. thaliana roots and promoted growth, increasing leaf area and biomass.
Journal Article
Evaluation of the Bioactive Compounds of Apis mellifera Honey Obtained from the Açai (Euterpe oleracea) Floral Nectar
by
Pereira, Daniel S.
,
Rogez, Hervé L. G.
,
Muto, Nilton A.
in
africanized honey bee
,
Amino acids
,
Analysis
2024
The biodiversity of Brazil provides an excellent climate and favorable pollination conditions for Apis mellifera L., especially in the Eastern Amazon region, which boasts vast floral wealth, including an abundance of açaí (Euterpe oleracea) flowers and fruits. In the present study, seven types of honey were evaluated: three containing floral nectar from açaí (Açaí honey) collected in the Eastern Amazon region (Açaí honey from Breu Branco (AH1 and AH2) and Açaí honey from Santa Maria (AH3), both from the state of Pará, Brazil) and four honeys from different regions of Brazil (Aroeira honey from Minas Gerais, Cipó-Uva honey from Distrito Federal, Mangue honey from Pará, and Timbó honey from Rio Grande do Sul). The characteristics of these honeys were evaluated by examining their physicochemical properties, melissopalynological aspects, color, antioxidant potential, and their constituent compounds, which were confirmed through GC-MS analysis. Açaí floral nectar honeys presented physicochemical results similar to those of other honeys, aligning with Brazilian legislation norms, but differed in their high values of free acidity, apparent sugars, and lower reducing sugars, which are directly related to their botanical origin. These differences correlate with unique flavor and distinct aroma characteristics. Melissopalynological analysis confirmed the botanical origin of the honeys containing açaí floral nectar, which had a color range from amber to dark amber. The three açaí honeys demonstrated high antioxidant capacity and superior flavonoid and polyphenol content compared to other honeys, particularly the açaí honey from Breu Branco (AH1), which had four times the content to combat free radicals compared to the honey with the highest potential (Aroeira honey). GC-MS analysis confirmed the presence of antioxidant properties as well as potential anti-inflammatory, antibacterial, antimicrobial, and antitumor capabilities in açaí honeys, which have not yet been fully studied.
Journal Article
Amazonian soil fungi are efficient degraders of glyphosate herbicide; novel isolates of Penicillium, Aspergillus, and Trichoderma
by
Correa, L. O.
,
Cortez, A. C. A.
,
Souza, J. V. B.
in
Agrochemicals
,
amazonian soil fungi
,
Aspergillus
2023
Abstract Pesticide residues that contaminate the environment circulate within the hydrological cycle can accumulate within the food chain and cause problems to both environmental and human health. Microbes, however, are well known for their metabolic versatility and the ability to degrade chemically stable substances, including recalcitrant xenobiotics. The current study focused on bio-prospecting within Amazonian rainforest soils to find novel strains fungi capable of efficiently degrading the agriculturally and environmentally ubiquitous herbicide, glyphosate. Of 50 fungal strains isolated (using culture media supplemented with glyphosate as the sole carbon-substrate), the majority were Penicillium strains (60%) and the others were Aspergillus and Trichoderma strains (26 and 8%, respectively). All 50 fungal isolates could use glyphosate as a phosphorous source. Eight of these isolates grew better on glyphosate-supplemented media than on regular Czapek Dox medium. LC-MS revealed that glyphosate degradation by Penicillium 4A21 resulted in sarcosine and aminomethylphosphonic acid. Resumo Resíduos de agrotóxicos que contaminam o meio ambiente circulam no ciclo hidrológico, podendo se acumular na cadeia alimentar e causar problemas tanto à saúde ambiental quanto humana. Por sua vez, microrganismos são bem conhecidos por sua versatilidade metabólica e capacidade de degradar substâncias quimicamente estáveis, incluindo xenobióticos recalcitrantes. O estudo atual se concentrou na bioprospecção nos solos da floresta amazônica para encontrar novas linhagens de fungos capazes de degradar com eficiência o herbicida onipresente na agricultura e no meio ambiente, o glifosato. Entre os 50 fungos isolados (usando meio de cultura suplementado com glifosato como única fonte de carbono), a maioria eram isolados do gênero Penicillium (60%) e os outros eram isolados de Aspergillus e Trichoderma (26 e 8%, respectivamente). Todos os 50 isolados de fungos foram capazes de usar glifosato como fonte de fósforo. Oito desses isolados cresceram melhor em meio suplementado com glifosato do que em meio Czapek Dox regular. LC-MS revelou que a degradação do glifosato por Penicillium 4A21 resultou nos metabólitos sarcosina e ácido aminometilfosfônico.
Journal Article