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1.
Cryo Letters ; 44(3): 151-159, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37883168

RESUMO

BACKGROUND: Semen cryopreservation is a biotechnology used frequently in animal production; however, there are some obstacles, such as those caused by high levels of reactive oxygen species (ROS). Moringa oleifera (MO) is known as a potent source of antioxidants and might be an important adjuvant. OBJECTIVE: The objective of this study was to determine the effect of different concentrations of MO extract supplementation on goat semen cryopreservation efficiency. MATERIALS AND METHODS: Ejaculates (n=6) from four goat breeders were pooled and diluted in skimmed milk (SM) or Tris-egg yolk (TEY)-based extenders and supplemented with different concentrations of MO extract (0, 1, 2 and 5 mg/mL). After the freeze-thaw cycle, sperm kinetics and viability were assessed. RESULTS: With the SM extender, straightness, wobble and plasma membrane integrity were lower than in the control group (P < 0.05). With the TEY extender, wobble was lower in with 5 mg/mL MO extract than in the control group (P < 0.05). As regards sperm ultrastructure, evaluated by SEM, the MO extract, regardless of the diluent used, damaged the membrane of sperm cells in a dose-dependent manner. CONCLUSION: The addition of aqueous extract of MO leaves in both diluents at all concentrations tested affects the parameters of sperm progressivity and damages the plasma membrane in a dose-dependent manner. DOI: 10.54680/fr23310110712.


Assuntos
Moringa oleifera , Preservação do Sêmen , Masculino , Animais , Congelamento , Cabras , Criopreservação/veterinária , Motilidade dos Espermatozoides , Preservação do Sêmen/veterinária , Sementes , Espermatozoides , Gema de Ovo/química , Crioprotetores/farmacologia
2.
J Appl Microbiol ; 130(3): 745-754, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32750211

RESUMO

AIMS: To evaluate the anti-staphylococcal effects of lectins isolated from bark (MuBL), heartwood (MuHL) and leaves (MuLL) of Myracrodruon urundeuva. METHODS AND RESULTS: The lectins were evaluated for: effects on growth, aggregation, haemolytic activity and biofilm-forming ability of Staphylococcus aureus clinical isolates nonresistant (8325-4) and multidrug resistant (LAC USA300); interference with the expression of virulence genes (hla, rnaIII and spa) of the Agr system of S. aureus; and synergistic effect with the antibiotics cefoxitin and cefotaxime. MuBL, MuHL and MuLL reduced growth (minimal inhibitory concentration (MIC): 12·5-50 µg ml-1 ) and viability (minimal bactericidal concentration (MBC): 100 µg ml-1 ) of 8325-4 and LAC USA300 cells. MuLL (at ½MIC and MIC) reduced LAC USA300 agglutination. The lectins did not interfere with haemolytic activity and expression of hla, rnaIII and spa genes. Only MuHL was able to reduce the biofilm production by 8325-4 (50-400 µg ml-1 ) and LAC USA300 (400 µg ml-1 ). CONCLUSION: The M. urundeuva lectins showed antibacterial activity against nonresistant and resistant clinical isolates of S. aureus and synergistic effects with antibiotics in reducing growth and biofilm formation. SIGNIFICANCE AND IMPACT OF THE STUDY: This work reports bioactive molecules capable of acting as anti-staphylococcal agents, since there are increasing reports of multiresistant isolates of this bacterium.


Assuntos
Anacardiaceae/química , Antibacterianos/farmacologia , Lectinas de Plantas/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Testes de Aglutinação , Antibacterianos/isolamento & purificação , Biofilmes/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla , Sinergismo Farmacológico , Hemólise/efeitos dos fármacos , Humanos , Lectinas de Plantas/isolamento & purificação , Staphylococcus aureus/isolamento & purificação , Staphylococcus aureus/patogenicidade , Virulência/efeitos dos fármacos
3.
J Appl Microbiol ; 131(2): 671-681, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33342053

RESUMO

AIMS: To investigate the effects of the lectin from Punica granatum sarcotesta (PgTeL) on growth, viability, cell structure, biofilm formation and chitinase activity of Listeria monocytogenes. In addition, the effect of PgTeL on the adhesion and invasion of human cells (HeLa) was determined. METHODS AND RESULTS: PgTeL showed bacteriostatic and bactericidal effects on the strains L. monocytogenes N53-1 and EGD-e, causing morphometric alterations, cell aggregation, strong deformation and cell disruption. PgTeL inhibited biofilm formation by EGD-e and N53-1 and also interfered with the adhesion and invasion processes of EGD-e and N53-1 in HeLa cells. Finally, the chitinase activity of L. monocytogenes EGD-e was reduced in the presence of PgTeL, which can be involved in the inhibition of adhesion process. CONCLUSION: PgTeL is an antibacterial agent against L. monocytogenes, inhibiting growth and promoting cell death, as well as impairing biofilm formation and bacterial adhesion and invasion into human cells. SIGNIFICANCE AND IMPACT OF THE STUDY: The results stimulate future investigations on the potential of PgTeL for protection of contamination in food products.


Assuntos
Antibacterianos/farmacologia , Lectinas/farmacologia , Listeria monocytogenes/efeitos dos fármacos , Punica granatum , Aderência Bacteriana/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Células HeLa , Humanos , Listeria monocytogenes/fisiologia
4.
J Appl Microbiol ; 125(5): 1238-1252, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30053345

RESUMO

The resistance of micro-organisms to antimicrobial agents has been a challenge to treat animal and human infections, and for environmental control. Lectins are natural proteins and some are potent antimicrobials through binding to carbohydrates on microbial surfaces. Oligomerization state of lectins can influence their biological activity and maximum binding capacity; the association among lectin polypeptide chains can alter the carbohydrate-lectin binding dissociation rate constants. Antimicrobial mechanisms of lectins include the pore formation ability, followed by changes in the cell permeability and latter, indicates interactions with the bacterial cell wall components. In addition, the antifungal activity of lectins is associated with the chitin-binding property, resulting in the disintegration of the cell wall or the arrest of de novo synthesis from the cell wall during fungal development or division. Quorum sensing is a cell-to-cell communication process that allows interspecies and interkingdom signalling which coordinate virulence genes; antiquorum-sensing therapies are described for animal and plant lectins. This review article, among other approaches, evaluates lectins as antimicrobials.


Assuntos
Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Resistência Microbiana a Medicamentos , Fungos/efeitos dos fármacos , Lectinas/farmacologia , Animais , Infecções Bacterianas/microbiologia , Humanos , Micoses/microbiologia , Percepção de Quorum/efeitos dos fármacos
5.
J Appl Microbiol ; 123(4): 861-874, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28792661

RESUMO

AIMS: To evaluate the antibiofilm potential of water-soluble Moringa oleifera seed lectin (WSMoL) on Serratia marcescens and Bacillus sp. METHODS AND RESULTS: WSMoL inhibited biofilm formation by S. marcescens at concentrations lower than 2·6 µg ml-1 and impaired bacterial growth at higher concentrations, avoiding biofilm formation. For Bacillus sp., the lectin inhibited bacterial growth at all concentrations. The antibiofilm action of WSMoL is associated with damage to bacterial cells. WSMoL did not disrupt preformed S. marcescens biofilms but was able to damage cells inside them. On the other hand, the lectin reduced the number of cells in Bacillus sp. biofilm treated with it. WSMoL was able to control biofilm formation when immobilized on glass surface (116 µg cm-2 ), damaging S. marcescens cells and avoiding adherence of Bacillus sp. cells on glass. The Bacillus sp. isolate is member of Bacillus subtilis species complex and closely related to species of the conspecific 'amyloliquefaciens' group. CONCLUSION: WSMoL prevented biofilm development by S. marcescens and Bacillus sp. and the antibiofilm effect is also observed when the lectin is immobilized on glass. SIGNIFICANCE AND IMPACT OF THE STUDY: Taking together, our results provide support to the potential use of WSMoL for controlling biofilm formation by bacteria.


Assuntos
Antibacterianos/farmacologia , Bacillus/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Lectinas/farmacologia , Moringa oleifera/química , Extratos Vegetais/farmacologia , Serratia marcescens/efeitos dos fármacos , Antibacterianos/isolamento & purificação , Bacillus/fisiologia , Lectinas/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Sementes/química , Serratia marcescens/fisiologia
6.
J Appl Microbiol ; 119(3): 666-76, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26109449

RESUMO

AIMS: This work evaluated the antibacterial activity of a water-soluble Moringa oleifera seed lectin (WSMoL) by evaluating its effect on growth, survival and cell permeability of Bacillus sp., Bacillus cereus, Bacillus pumillus, Bacillus megaterium, Micrococcus sp., Pseudomonas sp., Pseudomonas fluorescens, Pseudomonas stutzeri and Serratia marcescens. In addition, the effect of lectin on membrane integrity of most sensitive species was also evaluated. All the tested bacteria are able to cause biocorrosion and some are also responsible for human infections. METHODS AND RESULTS: WSMoL inhibited the bacterial growth, induced agglutination and promoted the leakage of proteins from cells of all strains. Bactericidal effect was detected against Bacillus sp., B. pumillus, B. megaterium, Ps. fluorescens and Ser. marcescens. The bacteriostatic effect of lectin was evident with only 6 h of incubation. Fluorescence microscopy of Ser. marcescens showed that WSMoL caused loss of cell integrity and indicated an anti-biofilm activity of the lectin. CONCLUSIONS: WSMoL was active against the bacteria by inhibiting growth and affecting cell permeability. The lectin also interfered with membrane integrity of Ser. marcescens, the most sensitive species. SIGNIFICANCE AND IMPACT OF THE STUDY: The study indicates that WSMoL was active against bacteria that cause serious problems in both industrial and health sectors. Also, the study contributes for the 'state-of-art' on antibacterial mechanisms of lectins.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Lectinas/farmacologia , Moringa oleifera/química , Extratos Vegetais/farmacologia , Antibacterianos/química , Bactérias/crescimento & desenvolvimento , Lectinas/química , Viabilidade Microbiana/efeitos dos fármacos , Permeabilidade/efeitos dos fármacos , Extratos Vegetais/química , Sementes/química
7.
J Appl Microbiol ; 114(3): 672-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23190078

RESUMO

AIMS: Schinus terebinthifolius leaves are used for treating human diseases caused by micro-organisms. This work reports the isolation, characterization and antimicrobial activity of S. terebinthifolius leaf lectin (SteLL). METHODS AND RESULTS: The isolation procedure involved protein extraction with 0.15 mol l(-1) NaCl, filtration through activated charcoal and chromatography of the filtrate on a chitin column. SteLL is a 14-kDa glycopeptide with haemagglutinating activity that is inhibited by N-acetyl-glucosamine, not affected by ions (Ca(2+) and Mg(2+)) and stable upon heating (30-100 °C) as well as over the pH 5.0-8.0. The antimicrobial effect of SteLL was evaluated by determining the minimal inhibitory (MIC), bactericide (MBC) and fungicide (MFC) concentrations. Lectin was active against Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, Salmonella enteritidis and Staphylococcus aureus. Highest bacteriostatic and bactericide effects were detected for Salm. enteritidis (MIC: 0.45 µg ml(-1)) and Staph. aureus (MBC: 7.18 µg ml(-1)), respectively. SteLL impaired the growth (MIC: 6.5 µg ml(-1)) and survival (MFC: 26 µg ml(-1)) of Candida albicans. CONCLUSIONS: SteLL, a chitin-binding lectin, purified in milligram quantities, showed antimicrobial activity against medically important bacteria and fungi. SIGNIFICANCE AND IMPACT OF THE STUDY: SteLL can be considered as a new biomaterial for potential antimicrobial applications.


Assuntos
Anacardiaceae/química , Anti-Infecciosos/farmacologia , Extratos Vegetais/farmacologia , Lectinas de Plantas/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Candida albicans/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Hemaglutinação , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Folhas de Planta/química , Lectinas de Plantas/isolamento & purificação
8.
Childs Nerv Syst ; 29(12): 2301-5, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23743818

RESUMO

PURPOSE: Tuberous sclerosis complex (TSC) is associated with hamartomatous growths including subependymal giant cell astrocytomas (SEGAs). Although, SEGAs are slow-growing glioneuronal tumors, they represent a significant cause of morbidity and mortality due to the risk of sudden death from acute hydrocephalus. Neurosurgical resection has been the mainstay of therapy, since radiotherapy and chemotherapy were proved inefficient in those tumors. Recent studies support the use of everolimus for subependymal giant cell astrocytomas associated with tuberous sclerosis and suggest it might represent a disease-modifying treatment for other aspects of tuberous sclerosis. METHODS: We describe the clinical and radiological progression of three pediatric patients with definitive diagnosis of TSC and SEGA, which have been treated with everolimus. RESULTS: Up to 34 % sustained SEGA decrease was observed in the three cases. All three patients have experienced seizure control and two of them have showed cognitive and behavioral improvement. Everolimus has been well tolerated by all. No severe adverse events have been observed to date. CONCLUSION: Everolimus offers significant promise in treating SEGAs. Studies are required to explore optimal therapy duration and management upon discontinuing therapy.


Assuntos
Antineoplásicos/uso terapêutico , Astrocitoma/tratamento farmacológico , Neoplasias Encefálicas/tratamento farmacológico , Sirolimo/análogos & derivados , Esclerose Tuberosa/complicações , Adolescente , Astrocitoma/etiologia , Neoplasias Encefálicas/etiologia , Pré-Escolar , Everolimo , Feminino , Humanos , Masculino , Sirolimo/uso terapêutico
9.
Braz J Biol ; 83: e274084, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37585932

RESUMO

This work aimed to evaluate the chemical composition, antioxidant and antimicrobial activities from crude extract and fractions from leaves of Eugenia uniflora Linn. The crude extract was obtained by turbo extraction and their fractions by partitioning. Chromatographic analysis were performed, and the antioxidant capacity was verified by two methods (DPPH• and ABTS•+). The Minimal Inhibitory/Bactericidal Concentration were conducted against twenty-two bacteria, selecting five strains susceptible to extract/fractions and resistant to the antibiotics tested. Ampicillin, azithromycin, ciprofloxacin, and gentamicin were associated with Ethyl Acetate Fraction (EAF) against multidrug-resistant strains in modulatory and checkerboard tests. The chromatographic data showed gallic acid, ellagic acid, and myricitrin in crude extract, with enrichment in the EAF. The electron transfer activity demonstrated in the antioxidant tests is related to the presence of flavonoids. The Gram-positive strains were more susceptible to EAF, and their action spectra were improved by association, comprising Gram-negative bacilli. Synergisms were observed to ciprofloxacin and gentamicin against Pseudomonas aeruginosa colistin-resistant. The results demonstrate that the extract and enriched fraction obtained from the leaves of E. uniflora act as a promising natural alternative against multidrug-resistant bacteria.


Assuntos
Eugenia , Extratos Vegetais , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Antioxidantes , Eugenia/química , Testes de Sensibilidade Microbiana , Bactérias , Ciprofloxacina , Gentamicinas
10.
Inflammopharmacology ; 20(6): 315-22, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22271003

RESUMO

OBJECTIVE: The present work reports the purification and partial characterization of an antibacterial lectin (EmaL) obtained from Eugenia malaccensis seeds as well as the evaluation of its effect in the daily topical treatment of repairing process of cutaneous wounds in mice. MATERIALS AND METHODS: The cutaneous wound was produced by the incision of the skin and use of lectin in the treatment of mice cutaneous wounds was evaluated. Surgical wounds were treated daily with a topical administration of EmaL and parameters such as edema, hyperemia, scab, granulation and scar tissues as well as contraction of wounds were analyzed. RESULTS: A novel lectin, with a molecular mass of 14 kDa, was isolated from E. malaccensis using affinity chromatography. The lectin (EmaL) agglutinated glutaraldehyde-treated rabbit and human erythrocytes; the lectin-induced rabbit erythrocyte agglutination was inhibited by glucose, casein, ovalbumin and fetuin. Also, Emal was very effective in the inhibition of bacterial growth, with the best inhibition results obtained for Staphylococcus aureus. Inflammatory signals such as edema and hyperemia were statistically less intense when EmaL was applied compared to the control. The histopathological analysis showed that the treated injured tissue presented reepithelialization (complete or partial) and areas of transition more evidenced than those of the control group, especially due to well organized pattern of collagen fibers presented in the granulation fibrous tissue. CONCLUSION: Presented results are a preliminary indication of the pharmacological interest in using EmaL as antimicrobial agent and in the repairing process of cutaneous wounds.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Lectinas/química , Lectinas/farmacologia , Pele/efeitos dos fármacos , Syzygium/química , Cicatrização/efeitos dos fármacos , Administração Cutânea , Animais , Antibacterianos/isolamento & purificação , Eritrócitos/efeitos dos fármacos , Feminino , Tecido de Granulação/efeitos dos fármacos , Humanos , Lectinas/isolamento & purificação , Camundongos , Coelhos , Sementes/química , Staphylococcus aureus/efeitos dos fármacos
11.
Lett Appl Microbiol ; 53(2): 186-92, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21605145

RESUMO

AIMS: The aim of this work was to analyse the coagulant and antibacterial activities of lectin isolated from Moringa oleifera seeds that are used for water treatment. METHODS AND RESULTS: The water-soluble M. oleifera lectin (WSMoL) was separated from nonhemagglutinating components (NHC) by chitin chromatography. WSMoL fluorescence spectrum was not altered in the presence of ions that are often present in high concentrations in polluted waters. Seed extract, NHC and WSMoL showed coagulant activity on a turbid water model. Both NHC and WSMoL reduced the growth of Staphylococcus aureus, but only WSMoL caused a reduction in Escherichia coli. WSMoL was also more effective in reducing the growth of ambient lake water bacteria. CONCLUSIONS: Data obtained from this study indicate that WSMoL is a potential natural biocoagulant for water, reducing turbidity, suspended solids and bacteria. SIGNIFICANCE AND IMPACT OF THE STUDY: Moringa oleifera seeds are a material effective in the treatment of water.


Assuntos
Antibacterianos/farmacologia , Lectinas/farmacologia , Moringa oleifera/metabolismo , Sementes/metabolismo , Antibacterianos/metabolismo , Floculação , Lectinas/química , Lectinas/metabolismo , Eliminação de Resíduos Líquidos/métodos , Poluentes da Água/química , Purificação da Água/métodos
12.
J Mycol Med ; 31(2): 101074, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33183973

RESUMO

This work reports the effects of the water-soluble lectin from Moringa oleifera seeds (WSMoL) on growth and survival of Candida species. In addition, cellular alterations linked to the antifungal effect were investigated. The minimal inhibitory (MIC) and fungicidal (MFC) concentrations were determined and 24-h growth curves in absence and presence of lectin were established. Flow cytometry was used to evaluate the induction of apoptosis/necrosis, alterations in mitochondrial membrane potential (ΔΨm), and occurrence of lysosomal damage. WSMoL inhibited the growth of C. albicans, C. glabrata, C. krusei and C. parapsilosis with MIC of 20µg/mL. The lowest MFC (20µg/mL) was detected for C. glabrata and the highest (80µg/mL) for C. albicans and C. parapsilosis. The inhibitory effect started from the ninth to nineteenth hour of incubation depending on the fungal species. Incubation with the lectin at the MIC for 24h increased the number of cells undergoing apoptosis and necrosis. Hyperpolarization of the mitochondrial membrane was detected after 12-h treatment, followed by reduction of ΔΨm or depolarization after 24h. No lysosomal damage was detected in treated cells. In conclusion, WSMoL is a fungistatic and fungicide agent against Candida with differential effects depending on the species.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Lectinas/farmacologia , Moringa oleifera/química , Extratos Vegetais/farmacologia , Sementes/química , Animais , Apoptose/efeitos dos fármacos , Candida/classificação , Candida/patogenicidade , Lectinas/química , Testes de Sensibilidade Microbiana , Necrose , Solubilidade , Água
13.
J Mycol Med ; 30(2): 100965, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32307255

RESUMO

Cryptococcosis is an opportunistic systemic mycosis whose treatment is limited to three drugs. In this work, we evaluated the antifungal activity of a hexane extract (HE) from Spondias tuberosa leaves against Cryptococcus neoformans and Cryptococcus gattii. Minimal inhibitory concentrations (MIC) were determined, and putative mechanisms were evaluated by flow cytometry. In addition, an in vivo infection assay was performed using Tenebrio molitor larvae. Treatment with HE inhibited the growth of standard and clinical isolates of C. neoformans and C. gattii (MICs ranging from 0.78 to 3.12mg/mL), significantly (P<0.05) increased mitochondrial superoxide anion levels, and induced mitochondrial membrane depolarization, loss of lysosomal membrane integrity, and phosphatidylserine externalization. The mean survival time of C. gattii-infected T. molitor larvae significantly (P<0.05) increased from 1.225 days in control to 3.067 and 3.882 days in HE-treated groups (78 and 156mg/kg, respectively). In conclusion, HE showed anticryptococcal activity, induced mitochondrial and lysosomal damage in yeast cells, and exhibited anti-infective action against C. gattii in T. molitor larvae.


Assuntos
Anacardiaceae/química , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Criptococose/tratamento farmacológico , Hexanos/química , Animais , Antifúngicos/efeitos adversos , Antifúngicos/uso terapêutico , Criptococose/patologia , Cryptococcus gattii/citologia , Cryptococcus gattii/efeitos dos fármacos , Cryptococcus gattii/ultraestrutura , Cryptococcus neoformans/citologia , Cryptococcus neoformans/efeitos dos fármacos , Cryptococcus neoformans/ultraestrutura , Hexanos/farmacologia , Humanos , Larva/efeitos dos fármacos , Lisossomos/efeitos dos fármacos , Lisossomos/fisiologia , Testes de Sensibilidade Microbiana , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/fisiologia , Fitoterapia , Extratos Vegetais/química , Tenebrio/efeitos dos fármacos , Tenebrio/crescimento & desenvolvimento , Testes de Toxicidade
14.
Chemosphere ; 222: 364-370, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30710762

RESUMO

Two recombinant protease inhibitors from Bauhinia bauhinioides, rBbKI (kallikrein inhibitor) and rBbCI (cruzipain inhibitor) were evaluated for insecticidal activity against workers and soldiers of Nasutitermes corniger (order: Isoptera; family: Termitidae) through the inhibitors' effect on the insect's gut enzymes. The inhibitor rBbKI was more effective than rBbCI in inhibiting the termite's gut enzymes. The kallikrein inhibitor showed termiticidal activity in workers with an LC50 of 0.9 mg mL-1 after 4 days. Conversely, rBbKI did not affect the survival of soldiers and rBbCI did not show termiticidal activity against N. corniger. The two inhibitors showed different specificity towards the termite's gut enzymes, representing interesting tools to characterize N. corniger enzymes. The different effects of rBbKI and rBbCI on the termite's enzymes and survival may be linked to slight structural differences between these inhibitors.


Assuntos
Bauhinia/química , Inseticidas/farmacologia , Isópteros/enzimologia , Inibidores de Proteases/farmacologia , Animais , Cisteína Endopeptidases , Humanos , Calicreínas/antagonistas & inibidores , Proteínas de Protozoários/antagonistas & inibidores , Especificidade por Substrato
15.
Sci Total Environ ; 595: 633-641, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28411562

RESUMO

The oil well blowout releases hydrocarbons into the marine environment as an oil droplets and gas bubbles dispersion. The oil trajectory is strongly influenced by physical, chemical and biological processes. In general, the ocean oil drift studies are based on a two-dimensional approach, whereas the whole oil from a well blowout can be represented by a surface oil leak in the same geographical coordinates. This work is a case study, where MOHID software is used at the Campos Basin region, in which the Lagrangian results of the surface oil leaks were confronted to their well blowout scenarios in different conditions of depth, seasonality (summer and winter), and use of dispersants at the source of the leak. The research results reinforced the importance of the three-dimensional approach to the scenario of deep and ultra-deep waters, especially for cases in which the dispersant injection into the source of the leak was considered.

16.
Phytochemistry ; 67(6): 545-52, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16442573

RESUMO

Two Bowman-Birk type trypsin inhibitors (CmTI(1) and CmTI(2)) were purified from Cratylia mollis seeds by acetone precipitation, ion exchange, gel filtration and reverse-phase chromatography. CmTI(1) and CmTI(2), with 77 and 78 amino acid residues, respectively, were sequenced in their entirety and show a high structural similarity to Bowman-Birk inhibitors from other Leguminosae. The putative reactive sites of CmTI(1) are a lysine residue at position 22 and a tyrosine residue at position 49. Different reactive sites, as identified by their alignment with related inhibitors, were found for CmTI(2): lysine at position 22 and leucine at position 49. The dissociation constant K(i) of the complex with trypsin is 1.4 nM. The apparent molecular mass is 17 kDa without DDT and 11 kDa with reducing agent and heating.


Assuntos
Fabaceae/química , Sementes/química , Inibidores da Tripsina/química , Inibidores da Tripsina/isolamento & purificação , Sequência de Aminoácidos , Animais , Bovinos , Concentração de Íons de Hidrogênio , Espectrometria de Massas , Dados de Sequência Molecular , Desnaturação Proteica , Homologia de Sequência de Aminoácidos , Temperatura , Inibidores da Tripsina/classificação
17.
Water Res ; 39(6): 975-80, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15766952

RESUMO

Seed flour from Moringa oleifera is widely used as a natural coagulant for water treatment in developing countries. Extracts obtained by water soaking of M. oleifera intact seeds were investigated for the presence of lectin, trypsin inhibitor, tannin as well as antioxidant activity. A water soluble M. oleifera lectin (WSMoL) detected was mainly active with rabbit cells at pH 4.5; heat treatment, pH 7.0, fructose and porcine thyroglobulin abolished HA of WSMoL. Trypsin inhibitor or tannins were not detected; the antioxidant component (WSMoAC) reduced 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) was slower than catechin and was thermostable. The extracts showed a primary glycopolypeptide band of Mw 20,000; the main native acidic protein showed hemagglutinating activity. WSMoL may be involved in seed coagulant properties.


Assuntos
Antioxidantes/análise , Lectinas/análise , Moringa oleifera/química , Sementes/química , Purificação da Água/métodos , Animais , Compostos de Bifenilo , Catequina/química , Coagulantes/farmacologia , Radicais Livres/química , Hemaglutinação , Temperatura Alta , Concentração de Íons de Hidrogênio , Picratos/química , Extratos Vegetais/química , Coelhos , Taninos/isolamento & purificação , Inibidores da Tripsina/isolamento & purificação
18.
Bioresour Technol ; 88(1): 75-9, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12573567

RESUMO

A highly purified trypsin inhibitor was obtained from Echinodorus paniculatus when an extract prepared from E. paniculatus seed flour (25 gl(-1), with 0.1 M ammonium acetate buffer, pH 8.3, under agitation for 6 min at 28 degrees C) was chromatographed on Sephadex G-25 (12 mlh(-1)), followed by affinity chromatography on immobilized Cratylia mollis isolectins (Cra Iso 1,2,3-Sepharose). The column chromatography was performed at 24 degrees C; the matrix was washed (30 mlh(-1)) with 0.1 M sodium phosphate buffer, pH 7.4 or with the same buffer containing 0.2 M glucose, followed by application of inhibitor sample and elution with 0.015 M sodium borate buffer, pH 7.4, or 1.0 M NaCl. A purified fraction of inhibitor was obtained by gel filtration chromatography (GF-450/HPLC column). Trypsin inhibitory activity was eliminated when the inhibitor was treated with metaperiodate showing that the carbohydrate moiety was important for trypsin inhibition. Binding of inhibitor was also evaluated on immobilized concanavalin A (Con A-Sepharose) using previously described chromatographic conditions with results similar to Cra Iso 1,2,3-Sepharose chromatography.


Assuntos
Alismataceae/química , Inibidores Enzimáticos/isolamento & purificação , Fabaceae/química , Proteínas de Plantas/isolamento & purificação , Cromatografia de Afinidade , Concentração de Íons de Hidrogênio , Lectinas/química , Sementes/química , Inibidores da Tripsina , alfa-Amilases/antagonistas & inibidores
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