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1.
Braz. J. Vet. Res. Anim. Sci. (Online) ; 58: e173908, 2021. graf, tab
Article in English | LILACS, VETINDEX | ID: biblio-1344764

ABSTRACT

Pyometra has several immunological and molecular changes that are responsible for uterine inflammation and the disease may or may not have infections. This study aimed to isolate and identify bacteria in the uterine content of bitches with pyometra, to analyze the susceptibility profile to antibiotics, detect ß-lactamase enzyme production by phenotypic tests, and resistance genes to ß-lactams. Eighteen samples of uterine content were collected by aspiration puncture. The samples were inoculated in bacteriological media and identified by biochemical tests. Subsequently, antibiogram tests, screening for detection of ß-lactamases, and Real-Time PCR for detection of resistance genes was performed. Escherichia coli, Klebsiella spp., Enterobacter aerogenes, Citrobacter spp., Staphylococcus spp., and Streptococcus spp. were identified in the analyzed samples of uterine content. In the antibiogram test, 90.5% of the isolates showed resistance to at least one antibiotic, and of these, 36.8% were considered MDR, with three Staphylococcus spp., three E. coli, and one Klebsiellaspp. Concerning bacterial resistance to the groups of antibiotics tested, 38.1% of the isolates were resistant to at least one type of ß-lactam, 33.3% to tetracycline, 19.0% to aminoglycosides, and 14.3% to fluoroquinolones, macrolides, and trimethoprim-sulfamethoxazole. In the phenotypic test to detect ß-lactamase production, E. coli samples were negative and Klebsiella spp. was positive for the production of AmpC, which presented the blaCMY, blaSPM, and blaSIM genes. Bacteria that are resistant to antibiotics represent a great challenge and laboratory support is therefore essential, without which therapeutic success decreases and death may be inevitable.(AU)


A piometra apresenta diversas alterações imunológicas e moleculares que são responsáveis pela inflamação uterina, e a doença pode ser infecciosa ou não. O objetivo deste estudo foi isolar e identificar bactérias no conteúdo uterino de cadelas com piometra, analisar o perfil de suscetibilidade aos antibióticos, detectar a produção de enzimas ß-lactamase por testes fenotípicos e genes de resistência aos ß-lactâmicos. Dezoito amostras de conteúdo uterino foram coletadas por punção aspirativa. As amostras foram inoculadas em meio bacteriológico e identificadas por testes bioquímicos. Posteriormente, foram realizados testes de antibiograma, triagem para detecção de ß-lactamases e PCR em tempo real para detecção de genes de resistência. Escherichia coli, Klebsiella spp., Enterobacter aerogenes, Citrobacter spp., Staphylococcus spp. e Streptococcus spp. foram identificados nas amostras de conteúdo uterino analisadas. No teste de antibiograma, 90,5% dos isolados apresentaram resistência a pelo menos um antibiótico, e destes, 36,8% foram considerados MR, sendo três Staphylococcus spp., três E. coli e uma Klebsiella spp. Sobre a resistência bacteriana aos grupos de antibióticos testados, 38,1% dos isolados foram resistentes a pelo menos um tipo de ß-lactâmico, 33,3% à tetraciclina, 19,0% aos aminoglicosídeos e 14,3% às fluorquinolonas, macrolídeos e trimetoprim-sulfametoxazol. No teste fenotípico para detecção da produção de ß-lactamase, as amostras de E. coli foram negativas, e Klebsiella spp. foi positiva para a produção de AmpC, que apresentou os genes blaCMY, blaSPM e blaSIM. As bactérias resistentes aos antibióticos representam um grande desafio e, portanto, o suporte laboratorial é essencial, sem o qual o sucesso terapêutico diminui e a morte pode ser inevitável.(AU)


Subject(s)
Animals , Female , Dogs , Dogs/genetics , Dogs/microbiology , Pyometra/genetics , Genes , Anti-Bacterial Agents/isolation & purification
2.
Electron. j. biotechnol ; 44: 41-46, Mar. 2020. tab, ilus
Article in English | LILACS | ID: biblio-1087698

ABSTRACT

Background: The main objective of this study was to isolate fungi associated with Anthopleura xanthogrammica and measure their antimicrobial and enzymatic activities. A total of 93 fungal strains associated with A. xanthogrammica were isolated in this study, of which 32 isolates were identified using both morphological characteristics and internal transcribed spacer (ITS) sequence analysis. The antibacterial activities of 32 fungal isolates were tested against Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Edwardsiella tarda, Vibrio harveyi, Fusarium oxysporum, and Pyricularia oryzae by agar diffusion assay. Extracellular hydrolytic enzyme activities of the fungal isolates were determined by agar diffusion assays. Enzyme activities were detected from clear halo size. Results: The isolated fungi belonged to 18 genera within 7 taxonomic orders of 1 phylum. The genera Aspergillaceae were the most diverse and common. The antimicrobial activities of 32 isolates were evaluated, and 19 (59.4%) of fungi isolate displayed unique antimicrobial activities. All fungal strains displayed at least one enzyme activity. The most common enzyme activities in the fungi isolates were amylase and protease, while the least common were pectinase and xylanase. Conclusions: This is first report on the sea anemone-derived fungi with antimicrobial and enzyme activities. Results indicated that sea anemone is a hot spot of fungal diversity and a rich resource of bioactive natural products.


Subject(s)
Aspergillus/isolation & purification , Sea Anemones/microbiology , Anti-Bacterial Agents/isolation & purification , Peptide Hydrolases/metabolism , Phylogeny , Polygalacturonase/metabolism , Aspergillus/enzymology , Aspergillus/genetics , Bacteria/drug effects , DNA, Ribosomal Spacer , Biodiversity , Fungi/isolation & purification , Fungi/genetics , Amylases/metabolism , Anti-Bacterial Agents/pharmacology
3.
Braz. arch. biol. technol ; 63: e20190674, 2020. tab, graf
Article in English | LILACS | ID: biblio-1132236

ABSTRACT

Abstract Clusia grandiflora belongs to an important botanical family which is known for its medicinal value, however there are few reports in literature about the species, highlighting the relevance of this study. Anatomical studies with leaves and stems were performed using traditional techniques. In this investigation it was identified particularities of the species such as the presence of vascular system arranged in an opened arc-shaped with the flexed ends towards the inside of the arch with accessory bundles in the petiole. In histochemical studies, performed with different reagents, alkaloids, phenols substances, carbohydrates and lipids were located. The cytotoxic activity of the extracts was performed by tetrazole salt and showed promising results for ethanolic extracts of stems (IC50 human colon cells of 24.30 μg/ mL) and leaves (IC50 ascites gastric cells of 44.15 μg/ mL), without cell membrane disruption of erythrocytes. The antibacterial activity was evaluated by tryptic soy agar and minimal inhibitory concentration assays and showed positive results for Pseudomonas aeruginosa and Escherichia coli, with better result for adventitious roots (32 μg/ mL and 16 μg/ mL, respectively), stems (64 μg/ mL and 32 μg/ mL, respectively) and leaves (64 μg/ mL and 32 μg/ mL, respectively) ethanolic extracts. Thus, these studies were able to characterize the species and show its potential as promising source of active substances.


Subject(s)
Plant Extracts/pharmacology , Clusia/anatomy & histology , Clusia/chemistry , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Anti-Bacterial Agents/pharmacology , Toxicity Tests , Cell Line, Tumor , Lethal Dose 50 , Anti-Bacterial Agents/isolation & purification
4.
Braz. arch. biol. technol ; 63: e20180568, 2020. tab, graf
Article in English | LILACS | ID: biblio-1132273

ABSTRACT

Abstract Sophorolipids are glycolipids that have natural antimicrobial properties and present great potential in the pharmaceutical field. The present study aimed to produce sophorolipids from Candida bombicola using a chicken fat-based medium and evaluate the antimicrobial activity against Gram-negative (Proteus mirabilis, Escherichia coli, Salmonella enterica subsp. enterica) and Gram-positive bacteria (Enterococcus faecium, Staphylococcus aureus and Streptococcus mutans). The production of sophorolipids reached 27.86 g L-1. Based on the structural characterization, 73.55% of the sophorolipids present a mixture of acidic monoacetylated C18:2 and lactonic diacetylated C16:0, and 26.45% were present in the diacetylated C18:1 lactonic form. Bacteria submitted to sophorolipid exposure showed a reduction in viability at doses of 500 μg mL-1 and 2,000 μg mL-1 against Gram-positive and Gram-negative bacteria, respectively. These results suggest that sophorolipids produced in chicken fat medium may be used as antimicrobial agents to prevent or eliminate contamination by different pathogens.


Subject(s)
Candida/metabolism , Glycolipids/pharmacology , Enterococcus faecium/drug effects , Gram-Negative Bacteria/drug effects , Anti-Bacterial Agents/pharmacology , Proteus mirabilis/drug effects , Glycolipids/isolation & purification , Salmonella enterica/drug effects , Escherichia coli/drug effects , Anti-Bacterial Agents/isolation & purification
5.
Mem. Inst. Oswaldo Cruz ; 115: e200458, 2020. graf
Article in English | SES-SP, LILACS, SES-SP | ID: biblio-1135229

ABSTRACT

BACKGROUND Calotropis procera latex protein fraction (LP) was previously shown to protect animals from septic shock. Further investigations showed that LP modulate nitric oxide and cytokines levels. OBJECTIVES To evaluate whether the protective effects of LP, against lethal bacterial infection, is observed in its subfractions (LPPII and LPPIII). METHODS Subfractions (5 and 10 mg/kg) were tested by i.p. administration, 24 h before challenging with lethal injection (i.p.) of Salmonella Typhimurium. LPPIII (5 mg/kg) which showed higher survival rate was assayed to evaluate bacterial clearance, histopathology, leukocyte recruitment, plasma coagulation time, cytokines and NO levels. FINDINGS LPPIII protected 70% of animals of death. The animals given LPPIII exhibited reduced bacterial load in blood and peritoneal fluid after 24 h compared to the control. LPPIII promoted macrophage infiltration in spleen and liver. LPPIII restored the coagulation time of infected animals, increased IL-10 and reduced NO in blood. MAIN CONCLUSIONS LPPIII recruited macrophages to the target organs of bacterial infection. This addressed inflammatory stimulus seems to reduce bacterial colonisation in spleen and liver, down regulate bacterial spread and contribute to avoid septic shock.


Subject(s)
Animals , Plant Proteins/therapeutic use , Salmonella Infections/drug therapy , Plant Extracts/pharmacology , Calotropis/chemistry , Homeostasis/drug effects , Inflammation/drug therapy , Latex/chemistry , Anti-Bacterial Agents/therapeutic use , Plant Proteins/isolation & purification , Plant Proteins/pharmacology , Salmonella Infections/immunology , Salmonella Infections/microbiology , Down-Regulation , Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/pharmacology
6.
Prensa méd. argent ; 105(3): 124-129, may 2019. tab
Article in English | LILACS, BINACIS | ID: biblio-1025415

ABSTRACT

Streptococcus pyogenes is the most common cause of bacterial tonsillopharyngitis with a sore throat in children;it can also cause weakening sicknesses such as rheumatic beart disease and other suppurative sequelae; peritonsillar abscess and lymphadenitis. The present study was conducted to determine the occurrence of Streptococcus pyogenes organism and their antibiotics susceptibility usually used to treat tonsilitis in children. From the period 2015-2016, 210 swabs were collected from children complaining of acute tonsillitis who presented to the outpatient department of Al-Karama teaching hospital, Baghdad, Iraq. The results revelated that fortuy-one isolates (19,5%) cases were positive culture for S. pyogenes. The residual results; other organisms, mixed culture and negatively cultured were excluded form the study. The incidence of treptococcus pyogenes tonsillitis was most prvalent in the age group 5-7 years 25 (23.8%) and the lowest in the age group 14-16 years 1 (10%). The isolates showed the frequency resistance percentage to: azithromycin 26 (63.4%), erythromycin 24 (58.5%), clarithromycin 19 (46.3%), 6 (14.6%) toAmoxiclillin + Clavulanic acid (Augmentin) and Clindamycin 5 (12.2%). while some isolates showed the lowest resistance percentage to Cefotaxime 3 (7.3%). S. pyogenes were frequently sensitive to Clindamycin 36 (87.8%), Cefotaxime 32 (78%) and Amoxicillin/clavulanic acid 31 (75.6%). Streptococcal infections are a considerable problem in medical and health centers. The incidence of Streptococcus pyogenes tonsillitis was the most dominant in the age group 5-7 years and antibiotics Clindamycin, Cefotaxime, and Augmentin are more effective against these bacteria in patients with recurrent tonsillitis. The early diagnosis, appropriate infection control easures, and guidelines are needed to prevent the spread of the infections ant the development of complications among patients


Subject(s)
Humans , Child , Streptococcus pyogenes/pathogenicity , Tonsillitis , Early Diagnosis , Disease Susceptibility , Anti-Bacterial Agents/isolation & purification
7.
Rev. Soc. Bras. Med. Trop ; 52: e20180152, 2019. tab, graf
Article in English | LILACS | ID: biblio-1041546

ABSTRACT

Abstract INTRODUCTION: Introducing new antibiotics to the clinic is critical. METHODS: We adapted a plate method described by Kawaguchi and coworkers in 20131 for detecting inhibitory airborne microorganisms. RESULTS: We obtained 51 microbial colonies antagonist to Chromobacterium violaceum, purified and retested them, and of these, 39 (76.5%) were confirmed. They comprised 24 bacteria, 13 fungi, and 2 yeasts. Among the fungi, eight (61.5%) produced active extracts. Among the bacterial, yeast, and fungal strains, 17 (44.7%) and 12 (31.6%) were active against Candida albicans and Candida parapsilosis, respectively. CONCLUSIONS: The proposed screening method is a rapid strategy for discovering potential antibiotic producers.


Subject(s)
Bacteria/isolation & purification , Candida/drug effects , Chromobacterium/drug effects , Air Microbiology , Quorum Sensing , Fungi/isolation & purification , Anti-Bacterial Agents/isolation & purification , Bacteria/metabolism , Colony Count, Microbial , Fungi/metabolism , Anti-Bacterial Agents/metabolism , Anti-Bacterial Agents/pharmacology
8.
Braz. j. microbiol ; 49(3): 656-661, July-Sept. 2018. tab, graf
Article in English | LILACS | ID: biblio-951809

ABSTRACT

Abstract Hamelia patens, is a plant traditionally used to treat a variety of conditions among the Huastec people of Mexico. The objective of this study is to characterize the phenolic content and critically examine the antimicrobial activity of leaf extracts H. patens, obtained by maceration, Soxhlet and percolation, using ethanol as 70% solvent. Phenolic compounds are characterized by liquid chromatography, coupled to a High Resolution Mass Spectrometry, and the antimicrobial activity was studied from the inhibitory effect of each extract for Escherichia coli, Staphylococcus aureus, Salmonella typhi and S. paratyphi, and by the Minimum Bactericidal Concentration, the percentage of activity and the Index of Bacterial Susceptibility of each extract. The phenolic compound identified in different concentrations in the three extracts was epicatechin. The extracts obtained by the three methods had antimicrobial activity, however, there was no significant difference (p < 0.05) between the Minimum Bactericidal Concentration of the extracts obtained by maceration, percolation and Soxhlet. The results of this study contribute to the body of knowledge on the use of extracts in controlling microorganisms with natural antimicrobials.


Subject(s)
Phenols/isolation & purification , Phenols/pharmacokinetics , Plant Extracts/isolation & purification , Plant Extracts/pharmacokinetics , Hamelia/chemistry , Chemical Fractionation/methods , Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/pharmacology , Phenols/chemistry , Staphylococcus aureus/drug effects , Plant Extracts/chemistry , Microbial Sensitivity Tests , Escherichia coli/drug effects , Mexico , Anti-Bacterial Agents/chemistry
9.
Rev. Soc. Bras. Med. Trop ; 51(4): 533-536, July-Aug. 2018. tab, graf
Article in English | LILACS | ID: biblio-1041470

ABSTRACT

Abstract INTRODUCTION This aim of this study was to evaluate the antibacterial activity of fractions and isolates of Maytenus guianensis, a plant species used in Amazonian folk medicine. METHODS A disk diffusion technique was used to investigate the antibacterial potential. RESULTS The hexanic fractions and tingenone B isolate showed inhibitory effects against Staphylococcus aureus and Streptococcus pneumoniae. CONCLUSIONS These results indicate the antibacterial potential of this species and will enable future studies to identify novel therapeutic alternatives from this species.


Subject(s)
Staphylococcus aureus/drug effects , Streptococcus pneumoniae , Plant Extracts/pharmacology , Maytenus/chemistry , Escherichia coli/drug effects , Klebsiella pneumoniae/drug effects , Anti-Bacterial Agents/pharmacology , Disk Diffusion Antimicrobial Tests , Anti-Bacterial Agents/isolation & purification
10.
Braz. j. biol ; 78(2): 311-317, May-Aug. 2018. tab, graf
Article in English | LILACS | ID: biblio-888857

ABSTRACT

Abstract The aims of this research were first, to evaluate the antibacterial potential of commercial thyme essential oil against V. alginolyticus and V. parahaemolyticys and second, using the spray drying technique to produce microcapsules. chemical compounds of thyme oil and microcapsules were identified and quantified being thymol the chemical component present at the highest concentration. Oil-in-water (O/W) emulsions were prepared and the microcapsules were obtained with a spray dryer using maltodextrin as wall material (ratio 1:4). Thyme oil and the microcapsules exhibited antimicrobial activity against V. parahaemolyticus and V. alginolyticus. The spray drying process did not affect the antimicrobial activity of thyme essentialoil.


Resumo Os objetivos desta pesquisa foram avaliar o potencial antibacteriano do óleoessencial de tomilho sobre V. alginolyticus e V. parahaemolyticys e produzir microcápsulas através do processo de secagem por aspersão (spray dryer). Os compostos químicos do óleo essencial de tomilho e das microcápsulas foram identificados e quantificadaos. Foi preparada uma emulsão de óleo em água (O/A) e em seguida foram produzidas microcápsulas em um spray dryer utilizando-se óleo essencial de tomilho e maltodextrina como material de parede na proporção de 1:4 respectivamente. Entre os vários compostos identificados, o timol apresentou maior concentração. O óleo essencial de tomilho e as microcápsulas exibiram atividade antibacteriana sobre V. parahaemolyticus e V. alginolyticus. O processo de secagem por aspersão não afetou a atividade antibacteriana do óleo essencial de tomilho.


Subject(s)
Vibrio alginolyticus/drug effects , Thymus Plant/chemistry , Drug Compounding/methods , Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry
11.
Braz. j. microbiol ; 49(1): 152-161, Jan.-Mar. 2018. tab, graf
Article in English | LILACS | ID: biblio-889202

ABSTRACT

ABSTRACT The present investigation was designed to study the effect of an active compound isolated from Justicia wynaadensis against multi drug resistant organisms (MDRO's) associated with diabetic patients. The drug resistant pathogens implicated in wound and urinary tract infection of diabetic patients were isolated and identified by molecular sequencing. Solvent-solvent fractionation of crude methanol extract produced hexane, chloroform, ethyl acetate and methanol-water fraction, among which chloroform fraction was found to be potent when compared with other three fractions. Further, chloroform fraction was subjected to preparatory HPLC (High-Performance Liquid Chromatography), that produced four sub-fractions; chloroform HPLC fraction 1 (CHF1) through CHF4. Among the sub-fractions, CHF1 inhibited the pathogens effectively in comparison to other three sub-fractions. The purity of CHF1 was found to be >95%. Therefore, CHF1 was further characterized by NMR and FTIR analysis and based on the structure elucidated, the compound was found to be 3,3',4'-Trihydroxyflavone. The effective dose of this bioactive compound ranged from 32 µg/mL to 1.2 mg/mL. Thus, the present study shows that 3,3',4'-Trihydroxyflavone isolated from J. wynaadensis is an interesting biopharmaceutical agent and could be considered as a source of antimicrobial agent for the treatment of various infections and used as a template molecule for future drug development.


Subject(s)
Humans , Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , Diabetes Complications/microbiology , Flavonols/pharmacology , Justicia/chemistry , Plant Extracts/pharmacology , Urinary Tract Infections/microbiology , Wounds and Injuries/microbiology , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/isolation & purification , Bacterial Physiological Phenomena , Bacteria/genetics , Bacteria/isolation & purification , Flavonols/chemistry , Flavonols/isolation & purification , Microbial Sensitivity Tests , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Plant Leaves/chemistry
12.
Braz. j. med. biol. res ; 51(6): e7118, 2018. tab, graf
Article in English | LILACS | ID: biblio-889111

ABSTRACT

In this study, we investigated the chemical composition, and antioxidant and antibacterial properties of ethanolic extracts of propolis (EEP) from Melipona quadrifasciata quadrifasciata and Tetragonisca angustula. Chemical composition of EEP was determined by colorimetry and chromatographic (HPLC-DAD and UPLC-Q/TOF-MS/MS) analysis. Antimicrobial activity of EEP was evaluated against gram-positive (S. aureus, methicillin-resistant S. aureus, E. faecalis) and gram-negative (E. coli and K. pneumoniae) bacteria by the minimal inhibitory concentration (MIC) test using the microdilution method. Furthermore, the growth curve and integrity of cell membrane of S. aureus and E. coli were investigated using standard microbiological methods. HPLC-DAD analysis showed that the EEP of M. quadrifasciata quadrifasciata has a more complex chemical composition than the EEP of T. angustula. Moreover, UPLC-MS analyses of M. quadrifasciata quadrifascita indicated flavonoids and terpenes as major constituents. The bactericidal activity of both EEPs was higher against gram-positive bacteria than for gram-negative bacteria. The EEP from M. quadrifasciata quadrifasciata presented MIC values lower than the EEP from T. angustula for all tested bacteria. The EEP from M. quadrifasciata quadrifasciata caused lysis of the bacterial wall and release of intracellular components from both E. coli and S. aureus. Our findings indicate that the chemical composition of propolis from stingless bees is complex and depends on the species. The extract from M. quadrifasciata quadrifascita was more effective against gram-positive than gram-negative strains, especially against S. aureus and methicillin-resistant S. aureus compared to T. angustula extract, by a mechanism that involves disturbance of the bacterial cell membrane integrity.


Subject(s)
Animals , Anti-Bacterial Agents/pharmacology , Antioxidants/pharmacology , Bees/classification , Gram-Negative Bacteria/drug effects , Propolis/chemistry , Anti-Bacterial Agents/isolation & purification , Antioxidants/isolation & purification , Chromatography, High Pressure Liquid , Colorimetry , Gram-Negative Bacteria/classification , Gram-Positive Bacteria/classification , Microbial Sensitivity Tests , Tandem Mass Spectrometry
13.
Braz. j. microbiol ; 48(4): 809-814, Oct.-Dec. 2017. graf
Article in English | LILACS | ID: biblio-889176

ABSTRACT

ABSTRACT This study aimed to describe a Bacillus subtilis expression system based on genetically modified B. subtilis. Abaecin, an antimicrobial peptide obtained from Apis mellifera, can enhance the effect of pore-forming peptides from other species on the inhibition of bacterial growth. For the exogenous expression, the abaecin gene was fused with a tobacco etch virus protease cleavage site, a promoter Pglv, and a mature beta-glucanase signal peptide. Also, a B. subtilis expression system was constructed. The recombinant abaecin gene was expressed and purified as a recombinant protein in the culture supernatant. The purified abaecin did not inhibit the growth of Escherichia coli strain K88. Cecropin A and hymenoptaecin exhibited potent bactericidal activities at concentrations of 1 and 1.5 µM. Combinatorial assays revealed that cecropin A and hymenoptaecin had sublethal concentrations of 0.3 and 0.5 µM. This potentiating functional interaction represents a promising therapeutic strategy. It provides an opportunity to address the rising threat of multidrug-resistant pathogens that are recalcitrant to conventional antibiotics.


Subject(s)
Antimicrobial Cationic Peptides/genetics , Antimicrobial Cationic Peptides/metabolism , Bacillus subtilis/genetics , Genetic Vectors/genetics , Insect Proteins/genetics , Insect Proteins/metabolism , Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/metabolism , Anti-Bacterial Agents/pharmacology , Antimicrobial Cationic Peptides/isolation & purification , Antimicrobial Cationic Peptides/pharmacology , Bacillus subtilis/metabolism , Escherichia coli/drug effects , Escherichia coli/growth & development , Gene Expression , Genetic Vectors/metabolism , Insect Proteins/isolation & purification , Insect Proteins/pharmacology , Protein Engineering , Protein Transport , Recombinant Proteins/genetics , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Recombinant Proteins/pharmacology
14.
An. acad. bras. ciênc ; 89(4): 2825-2832, Oct.-Dec. 2017. tab, graf
Article in English | LILACS | ID: biblio-886866

ABSTRACT

ABSTRACT Abnormal multiplication of oral bacteria causes dental caries and dental plaque. These diseases continue to be major public health concerns worldwide, mainly in developing countries. In this study, the chemical composition and antimicrobial activity of the essential oil of Vitex agnus-castus leaves (VAC‒EO) collected in the North of Brazil against a representative panel of cariogenic bacteria were investigated. The antimicrobial activity of VAC-EO was evaluated in terms of its minimum inhibitory concentration (MIC) values by using the broth microdilution method in 96-well microplates. The chemical constituents of VAC-EO were identified by gas chromatography (GC‒FID) and gas chromatography‒mass spectrometry (GC‒MS). VAC‒EO displayed some activity against all the investigated oral pathogens; MIC values ranged from 15.6 to 200 μg/mL. VAC-EO had promising activity against Streptococcus mutans (MIC= 15.6 μg/mL), Lactobacillus casei (MIC= 15.6 μg/mL), and Streptococcus mitis (MIC= 31.2 μg/mL). The compounds 1,8-cineole (23.8%), (E)-β-farnesene (14.6%), (E)-caryophyllene (12.5%), sabinene (11.4%), and α-terpinyl acetate (7.7%) were the major chemical constituents of VAC‒EO. VAC-EO displays antimicrobial activity against cariogenic bacteria. The efficacy of VAC-EO against S. mutans is noteworthy and should be further investigated.


Subject(s)
Sesquiterpenes/pharmacology , Plant Extracts/pharmacology , Lamiaceae/chemistry , Vitex/chemistry , Dental Caries/drug therapy , Lactobacillus casei/drug effects , Anti-Bacterial Agents/pharmacology , Plants, Medicinal , Sesquiterpenes/classification , Streptococcus mutans , Brazil , Oils, Volatile/isolation & purification , Oils, Volatile/pharmacology , Polycyclic Sesquiterpenes , Gas Chromatography-Mass Spectrometry , Anti-Bacterial Agents/isolation & purification
15.
Mem. Inst. Oswaldo Cruz ; 112(10): 692-697, Oct. 2017. tab, graf
Article in English | LILACS | ID: biblio-894841

ABSTRACT

BACKGROUND Endophytic fungi, present mainly in the Ascomycota and Basidiomycota phyla, are associated with different plants and represent important producers of bioactive natural products. Brazil has a rich biodiversity of plant species, including those reported as being endemic. Among the endemic Brazilian plant species, Vellozia gigantea (Velloziaceae) is threatened by extinction and is a promising target to recover endophytic fungi. OBJECTIVE The present study focused on bioprospecting of bioactive compounds of the endophytic fungi associated with V. gigantea, an endemic, ancient, and endangered plant species that occurs only in the rupestrian grasslands of Brazil. METHODS The capability of 285 fungal isolates to produce antimicrobial and antimalarial activities was examined. Fungi were grown at solid-state fermentation to recover their crude extracts in dichloromethane. Bioactive extracts were analysed by chromatographic fractionation and NMR and displayed compounds with antimicrobial, antimycobacterial, and antimalarial activities. FINDINGS Five fungi produced antimicrobial and antimalarial compounds. Extracts of Diaporthe miriciae showed antifungal, antibacterial, and antimalarial activities; Trichoderma effusum displayed selective antibacterial activity against methicillin-resistant Staphylococcus aureus and Mycobacterium intracellulare; and three Penicillium species showed antibacterial activity. D. miriciae extract contained highly functionalised secondary metabolites, yielding the compound epoxycytochalasin H with high antimalarial activity against the chloroquine-resistant strain of Plasmodium falciparum, with an IC50 approximately 3.5-fold lower than that with chloroquine. MAIN CONCLUSION Our results indicate that V. gigantea may represent a microhabitat repository hotspot of potential fungi producers of bioactive compounds and suggest that endophytic fungal communities might be an important biological component contributing to the fitness of the plants living in the rupestrian grassland.


Subject(s)
Plasmodium/drug effects , Microbial Sensitivity Tests , Magnoliopsida/classification , Magnoliopsida/microbiology , Mitosporic Fungi/drug effects , Gram-Negative Aerobic Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/pharmacology , Antifungal Agents/isolation & purification , Antifungal Agents/pharmacology , Antimalarials/isolation & purification , Antimalarials/pharmacology , Tropical Climate , Biological Assay , Candida/drug effects , Endophytes/chemistry
16.
An. acad. bras. ciênc ; 89(3): 1907-1915, July-Sept. 2017. tab
Article in English | LILACS | ID: biblio-886748

ABSTRACT

ABSTRACT Many essential oils (EOs) of different plant species possess interesting antimicrobial effects on buccal bacteria and antioxidant properties. Eugenia klotzschiana Berg (pêra-do-cerrado, in Portuguese) is a species of Myrtaceae with restricted distribution in the Cerrado. The essential oils were extracted through the hydrodistillation technique using a modified Clevenger apparatus (2 hours) and chemically characterized by GC-MS. The major compounds were α-copaene (10.6 %) found in oil from leaves in natura, β-bisabolene (17.4 %) in the essential oil from dry leaves and α-(E)-bergamotene (29.9 %) in oil from flowers. The antioxidant activity of essential oils showed similarities in both methods under analysis (DPPH and ABTS˙+) and the results suggested moderate to high antioxidant activity. The antibacterial activity was evaluated by determining minimum inhibitory concentrations (MICs), using the microdilution method. MIC values below 400 µg/mL were obtained against Streptococcus salivarius (200 µg/mL), S. mutans (50 µg/mL), S. mitis (200 µg/mL) and Prevotella nigrescens (50 µg/mL). This is the first report of the chemical composition and antibacterial and antioxidant activities of the essential oils of E. klotzschiana. These results suggest that E. klotzschiana, a Brazilian plant, provide initial evidence of a new and alternative source of substances with medicinal interest.


Subject(s)
Streptococcus/drug effects , Prevotella/drug effects , Plant Leaves/chemistry , Flowers/chemistry , Eugenia/chemistry , Anti-Bacterial Agents/pharmacology , Antioxidants/pharmacology , Microbial Sensitivity Tests , Gas Chromatography-Mass Spectrometry , Anti-Bacterial Agents/isolation & purification , Antioxidants/isolation & purification
17.
An. acad. bras. ciênc ; 89(3): 1555-1564, July-Sept. 2017. tab, graf
Article in English | LILACS | ID: biblio-886762

ABSTRACT

ABSTRACT Diarrhea is an infectious disease caused by bacterial, virus, or protozoan, and dengue is caused by virus, included among the neglected diseases in several underdeveloped and developing countries, with an urgent demand for new drugs. Considering the antidiarrheal potential of species of Maytenus genus, a phytochemical investigation followed by antibacterial activity test with extracts of branches and heartwood and bark of roots from Maytenus gonoclada were conducted. Moreover, due the frequency of isolation of lupeol from Maytenus genus the antiviral activity against Dengue virus and cytotoxicity of lupeol and its complex with β-cyclodextrins were also tested. The results indicated the bioactivity of ethyl acetate extract from branches and ethanol extract from heartwood of roots of M. gonoclada against diarrheagenic bacteria. The lupeol showed potent activity against Dengue virus and low cytotoxicity in LLC-MK2 cells, but its complex with β-cyclodextrin was inactive. Considering the importance of novel and selective antiviral drug candidates the results seem to be promising.


Subject(s)
Antiviral Agents/pharmacology , Plant Extracts/pharmacology , Maytenus/chemistry , Dengue Virus/drug effects , Pentacyclic Triterpenes/pharmacology , Anti-Bacterial Agents/pharmacology , Antidiarrheals/pharmacology , Antiviral Agents/isolation & purification , Cell Line , Maytenus/classification , Pentacyclic Triterpenes/isolation & purification , Anti-Bacterial Agents/isolation & purification , Antidiarrheals/isolation & purification
18.
An. acad. bras. ciênc ; 89(3,supl): 2327-2340, 2017. tab, graf
Article in English | LILACS | ID: biblio-886786

ABSTRACT

ABSTRACT To the fungal microbiota the UFPE and biotechnological potential enzymatic and antimicrobial production. Air conditioned environments were sampled using a passive sedimentation technique, the air I ratio and the presence of aflatoxigenic strains evaluated for ANVISA. Icelles were to determine the enzymatic activity of lipase, amylase and protease metabolic liquids to determine antimicrobial activity. Diversity was observed in all CAV environments, CFU/m3 ranged from 14 to 290 and I/E ratio from 0.1 to 1.5. The of the fungal genera were: Aspergillus (50%), Penicillium (21%), Talaromyces (14%), Curvularia and Paecilomyces (7% each). Aspergillus sydowii (Bainier & Sartory) Thom & Church presented enzymatic activity and the Talaromyces purpureogenus Samson, Yilmaz, Houbraken, Spierenb., Seifert, Peterson, Varga & Frisvad presented antibacterial activity against all bacteria that all environments present fungal species biodiversity no toxigenic or pathogenic fungi were found, according to ANVISA legislation for conditioned environments and airborne filamentous fungi present potential for enzymatic and antimicrobial activity.


Subject(s)
Aflatoxins/isolation & purification , Biodiversity , Air Microbiology , Fungi/isolation & purification , Fungi/enzymology , Anti-Bacterial Agents/isolation & purification , Universities , Brazil , Public Sector , Aflatoxins/pharmacology , Air Conditioning , Fungi/classification , Anti-Bacterial Agents/pharmacology
19.
Rev. biol. trop ; 64(2): 733-745, abr.-jun. 2016. tab, ilus
Article in English | LILACS | ID: biblio-843309

ABSTRACT

AbstractPasteurella multocida is an important veterinary pathogen causing infections in animals and birds. Nowadays, different reports have described the severity of infections, increasing resistance of micro-organisms to antibiotics, and the contribution of ethnoveterinary practices towards the treatment of various ailments of animals. The aim of the present study was to investigate the antibacterial efficacy of the ethanolic extracts of endophytic fungi against P. multocida Capsular Type A strains. A total of six endophytic fungi were isolated from two tropical ethnoveterinary plants: Garcinia xanthochymus H. and Polygonum chinense L. The ethanolic extracts of the endophytic fungi were subjected to in vitro antimicrobial activity by the well diffusion method. Besides, we evaluated the treatment of mice with the potent fungal extract and observed the effects in different organs under electron microscopy. Our results showed that four fungi had antimicrobial activity against the selected pathogen. The best antibacterial activity was showed by the extract of the endophytic fungi, Glomerella magna isolated from G. xanthochymus, with a minimum inhibitory concentration of 46.9 µg/mL and minimum bactericidal concentration of 750 µg/mL. Treatment of mice with the potent fungal extract caused a considerable inhibitory effect on the pathogen growth in vital organs, results that was also confirmed by histopathological studies made by scanning electron microscopy. The present findings indicated that the endophytic fungi G. magna has the potential to provide an effective treatment against infections caused by Pasteurella multocida. However, the isolation of bioactive components needs further investigation. Rev. Biol. Trop. 64 (2): 733-745. Epub 2016 June 01.


ResumenPasteurella multocida es un importante patógeno veterinario que causa infecciones en animales y aves. Hoy en día, diferentes informes han descrito la gravedad de las infecciones, aumentando la resistencia de los microorganismos a los antibióticos, y la contribución de las prácticas etnoveterinarias hacia el tratamiento de diversas enfermedades de los animales. El objetivo del presente estudio fue investigar la eficacia antibacteriana de los extractos etanólicos de hongos endófitos contra cepas de P. multocida tipo capsular A. Un total de seis hongos endófitos fueron aisladas de dos plantas etnoveterinarias tropicales: Garcinia xanthochymus H. y Polygonum chinense L. Los extractos etanólicos de los hongos endófitos fueron sometidos a la actividad antimicrobiana in vitro por el método de difusión. Además, se evaluó el tratamiento de ratones con el extracto de hongos potente y observamos los efectos en diferentes órganos bajo el microscopio electrónico. Nuestros resultados mostraron que cuatro hongos tenían actividad antimicrobiana contra el patógeno seleccionado. La mejor actividad antibacteriana la mostró el extracto de los hongos endófitos, Glomerella magna aislado de G. xanthochymus, con una concentración inhibitoria mínima de 46.9 mg/ml y la concentración bactericida mínima de 750 mg/ml. El tratamiento de ratones con el extracto de hongos potente causó un considerable efecto inhibidor sobre el crecimiento de patógenos en órganos vitales, resultados que también fueron confirmados por estudios histopatológicos realizados por microscopía electrónica de barrido. Los presentes hallazgos indican que el hongos endófitos G. magna tienen el potencial de proporcionar un tratamiento eficaz contra las infecciones causadas por Pasteurella multocida. Sin embargo, el aislamiento de componentes bioactivos necesita más investigación.


Subject(s)
Animals , Rabbits , Pasteurella multocida/drug effects , Polygonum/microbiology , Garcinia/microbiology , Endophytes/chemistry , Liver/drug effects , Anti-Bacterial Agents/pharmacology , Microscopy, Electron, Scanning , Pasteurella multocida/ultrastructure , Disk Diffusion Antimicrobial Tests , Endophytes/isolation & purification , Liver/ultrastructure , Anti-Bacterial Agents/isolation & purification
20.
Braz. j. microbiol ; 46(4): 1111-1118, Oct.-Dec. 2015. tab, graf
Article in English | LILACS | ID: lil-769642

ABSTRACT

Abstract In the present work, twelve bacilli were isolated from four different regions of human skin from Bela population of Nagpur district, India. The isolated bacilli were identified by their morphological, cultural and biochemical characteristics. Seven isolates were Gram negative rods, out of which five were belong to genus Pseudomonas. Three among the five Gram positive isolates were identified as Dermabactor and the remaining two Bacillus. Their antimicrobial susceptibility profile was determined by Kirby-Bauer disc diffusion method. The isolates showed resistance to several currently used broad-spectrum antibiotics. The Dermabactor genus was resistant to vancomycin, although it was earlier reported to be susceptible. Imipenem was found to be the most effective antibiotic for Pseudomonas while nalidixic acid, ampicillin and tetracycline were ineffective. Isolates of Bacillus displayed resistance to the extended spectrum antibiotics cephalosporin and ceftazidime. Imipenem, carbenicillin and ticarcillin were found to be the most effective antibiotics as all the investigated isolates were susceptible to them. Antibiotic resistance may be due to the overuse or misuse of antibiotics during the treatment, or following constant exposure to antibiotic-containing cosmetic formulations.


Subject(s)
Adolescent/classification , Adolescent/drug effects , Adolescent/genetics , Adolescent/isolation & purification , Adolescent/microbiology , Adolescent/pharmacology , Adult/classification , Adult/drug effects , Adult/genetics , Adult/isolation & purification , Adult/microbiology , Adult/pharmacology , Anti-Bacterial Agents/classification , Anti-Bacterial Agents/drug effects , Anti-Bacterial Agents/genetics , Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/microbiology , Anti-Bacterial Agents/pharmacology , Bacillus/classification , Bacillus/drug effects , Bacillus/genetics , Bacillus/isolation & purification , Bacillus/microbiology , Bacillus/pharmacology , Female/classification , Female/drug effects , Female/genetics , Female/isolation & purification , Female/microbiology , Female/pharmacology , Healthy Volunteers/classification , Healthy Volunteers/drug effects , Healthy Volunteers/genetics , Healthy Volunteers/isolation & purification , Healthy Volunteers/microbiology , Healthy Volunteers/pharmacology , Humans/classification , Humans/drug effects , Humans/genetics , Humans/isolation & purification , Humans/microbiology , Humans/pharmacology , Male/classification , Male/drug effects , Male/genetics , Male/isolation & purification , Male/microbiology , Male/pharmacology , Microbial Sensitivity Tests/classification , Microbial Sensitivity Tests/drug effects , Microbial Sensitivity Tests/genetics , Microbial Sensitivity Tests/isolation & purification , Microbial Sensitivity Tests/microbiology , Microbial Sensitivity Tests/pharmacology , Middle Aged/classification , Middle Aged/drug effects , Middle Aged/genetics , Middle Aged/isolation & purification , Middle Aged/microbiology , Middle Aged/pharmacology , Skin/classification , Skin/drug effects , Skin/genetics , Skin/isolation & purification , Skin/microbiology , Skin/pharmacology , Young Adult/classification , Young Adult/drug effects , Young Adult/genetics , Young Adult/isolation & purification , Young Adult/microbiology , Young Adult/pharmacology
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