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1.
Arq. Inst. Biol ; 87: e0122019, 2020. tab, graf
Article in English | ID: biblio-1117631

ABSTRACT

The objective of this study was to evaluate the effect of timbó seed coat on the physiological and sanitary quality of soybean seeds. Timbó seeds were collected from mature fruits in the Cerrado. The external layer of the seed coat was removed and crushed in a mill and used in the treatment of soybean seeds. Three lots of soybean seeds were used, from high, medium and low vigor seeds. The treatments were: powder; gel; hydroalcoholic extract; synthetic fungicide (Vitavax® - Thiram 200 sc), and untreated seeds. The physiological quality of the soybean seeds was determined by standard germination, accelerated aging, length, fresh and dry mass of seedlings. Blotter test was used to determine the sanitary quality. The statistical analyze used was a completely randomized 3 × 5 factorial design, considering three seed lots and five treatments. Treatment with the coat seed extract and gel improves the physiological quality of soybean seeds from low vigor lots. The treatment of seeds with gel decreases the incidence of Fusarium and Penicillium genus; and treatment with the powder reduced the incidence of the Cercospora genus.(AU)


O objetivo deste estudo foi avaliar o efeito do tegumento das sementes de timbó sobre a qualidade fisiológica e sanitária de sementes de soja. As sementes de timbó foram coletadas de frutos maduros, no Cerrado. A camada mais externa do tegumento das sementes foi retirada e triturada em moinho e utilizada no tratamento de sementes de soja. Foram utilizados três lotes de sementes de soja, provenientes de sementes de alto, médio e baixo vigor. Os tratamentos foram: pó, gel, extrato hidroalcoólico; fungicida sintético (Vitavax® - Thiram 200 sc) e sementes não tratadas. A qualidade fisiológica das sementes de soja foi determinada pelo teste padrão de germinação, envelhecimento acelerado, comprimento, massa fresca e seca de plântulas. Para a determinação da qualidade sanitária utilizou-se o teste de borrão (blotter test). O delineamento estatístico foi em esquema fatorial 3 × 5, inteiramente casualizado, considerando-se três lotes de sementes e cinco tratamentos. Os tratamentos com o extrato e o gel do tegumento das sementes de timbó melhoraram a qualidade fisiológica das sementes de soja provenientes de lotes de baixo vigor. O tratamento com gel do tegumento das sementes de timbó diminuiu a incidência de fungos dos gêneros Fusarium e Penicillium; e o tratamento com o pó reduziu a incidência do gênero Cercospora.(AU)


Subject(s)
Seeds/drug effects , Soybeans , Plant Extracts/pharmacology , Sapindaceae , Powders , Brazil , Food Quality , Germination/drug effects , Fungi/drug effects , Gels
2.
Braz. arch. biol. technol ; 63: e20190177, 2020. tab, graf
Article in English | LILACS | ID: biblio-1132206

ABSTRACT

Abstract: This article describes the chemical composition of Vernonia chalybaea essential oil, and investigates its antimicrobial, antioxidant and hemolytic activities. The evaluation of the antifungal activity was performed by the broth microdilution method using strains of yeasts and dermatophytic fungi. The checkerboard technique to find antimicrobial modulatory effects was performed using ketoconazole as standard drug. The antioxidant activity was evaluated by DPPH scavenging assay and β-carotene/linoleic-acid system. The toxicity was characterized by the brine shrimp lethality test and hemolysis bioassays. The essential oil was obtained by hydrodistillation and analyzed by GC-MS method, showing to be rich in the sesquiterpenes β-caryophyllene (39.06%) and bicyclogermacrene (19.69%), and also demonstrated a relevant antifungal activity against strains of Trichophyton rubrum. In the modulatory activity assay, the essential oil of V. chalybaea and β-caryophyllene demonstrated a synergistic interaction with ketoconazole, with increasing of its antifungal action. The antioxidant activity was evidenced mainly by β-carotene/linoleic acid system, with IC50 value of 35.87 ± 0.32 µg/mL. The results suggest that V. chalybaea essential oil and β-caryophyllene are valuable natural medicinal agents with antioxidant and antimicrobial activities.


Subject(s)
Humans , Animals , Oils, Volatile/pharmacology , Vernonia/chemistry , Ketoconazole/pharmacology , Antifungal Agents/pharmacology , Artemia , Bacteria/drug effects , Oils, Volatile/chemistry , Linoleic Acid/pharmacology , beta Karyopherins/pharmacology , Fungi/classification , Fungi/drug effects , Anti-Bacterial Agents/pharmacology , Antifungal Agents/chemistry , Antioxidants/pharmacology
3.
Rev. iberoam. micol ; 36(2): 55-60, 2019. tab
Article in English | LILACS, ColecionaSUS, CONASS, SES-RS | ID: biblio-1121303

ABSTRACT

Background: The number of fungal infections has increased in recent years in Rio Grande do Sul (RS), Brazil. Epidemiological studies are important for proper control of infections. Aims: To evaluate the etiology of fungal infections in patients in RS, from 2003 to 2015. Methods: This is a retrospective and longitudinal study carried out at Mycology Department of Central Laboratory of RS; 13,707 samples were evaluated. The variables sex, age, site of infection, and etiologic agent were analyzed. Susceptibility of Candida to fluconazole was tested in samples collected in 2015from 51 outpatients. Results: Of the 13,707 samples, 840 cases (6.12%) of fungal infections were found and included in the analyses; female gender accounted for the 55.9% of the cases. The main fungus was Candida albicans (450 cases, 53.38%; p < 0.001). Onychomycosis was the most frequent infection in superficial mycoses. Systemic mycoses accounted for 54.05% of the cases, from which 68.8% occurred in males, mainly HIVpositive (33.11%), and the main etiologic agent in these cases was Cryptococcus neoformans (73.13%). Among 51 samples tested for susceptibility to fluconazole, 78.43% of Candida isolates were susceptible; 5.88% were susceptible in a dose-dependent manner, and 15.69% were resistant. Conclusions: C. albicans is a common cause of fungal infections in RS, accounting for half of the cases;resistance to antifungals was found in non-hospitalized patients. In addition, women seem to be moresusceptible to fungal infections than men, however men show more systemic mycoses than women. Thenails are the most common site of infection. (AU)


Subject(s)
Humans , Male , Female , Infant, Newborn , Infant , Child, Preschool , Child , Adolescent , Adult , Middle Aged , Fungi/classification , Mycoses/epidemiology , Brazil/epidemiology , Fluconazole/pharmacology , Prevalence , Retrospective Studies , Longitudinal Studies , Drug Resistance, Fungal , Fungi/drug effects
4.
Braz. j. microbiol ; 49(4): 929-935, Oct.-Dec. 2018. tab, graf
Article in English | LILACS | ID: biblio-974283

ABSTRACT

ABSTRACT The objective of this study was to evaluate the antifungal activity of nanoemulsions encapsulating essential oil of oregano (Origanum vulgare), both in vitro and after application on Minas Padrão cheese. Nanodispersions were obtained by the phase inversion temperature method. Cladosporium sp., Fusarium sp., and Penicillium sp. genera were isolated from cheese samples and used to evaluate antifungal activity. Minimal inhibitory concentrations of non-encapsulated and encapsulated oregano essential oil were determined, and they were influenced by the encapsulation of the essential oil depending on the type of fungus. The antifungal activity of the nanoencapsulated oregano essential oil in cheese slices showed no evidence of an effect of the MICs, when applied in the matrix. On the other hand, an influence of contact time of the nanoemulsion with the cheese was observed, due to the increase in water activity. It was concluded that nanoencapsulated oregano essential oil presented an inhibitory effect against the three genera of fungi evaluated. If environmental parameters, such as storage temperature and water activity, were controlled, the inhibitory effect of nanoemulsions of oregano oil could possibly be greatly improved, and they could be presented as a potential alternative for the preservation of Minas Padrão cheese against fungal contamination.


Subject(s)
Oils, Volatile/pharmacology , Cheese/microbiology , Origanum/chemistry , Food Preservation/methods , Food Preservatives/pharmacology , Antifungal Agents/pharmacology , Oils, Volatile/analysis , Microbial Sensitivity Tests , Food Contamination/prevention & control , Cheese/analysis , Food Preservatives/analysis , Fungi/isolation & purification , Fungi/classification , Fungi/drug effects , Antifungal Agents/analysis
5.
An. bras. dermatol ; 93(3): 462-464, May-June 2018. tab
Article in English | LILACS | ID: biblio-1038269

ABSTRACT

Abstract: The number of new cases of emerging fungal infections has increased considerably in recent years, mainly due to the large number of immunocompromised individuals. The objective of this study was to evaluate the susceptibility of emerging fungi to fluconazole, itraconazole and amphotericin B by disk diffusion method. In 2015, 82 emerging fungi were evaluated in IPB-LACEN/RS and 13 (15.8%) were resistant: 10/52 were from superficial mycoses and 3/30 from systemic mycoses. The data from the study point to the need for permanent vigilance regarding the careful evaluation in the prescription and clinical and laboratory follow-up of patients affected by fungal infections.


Subject(s)
Humans , Male , Female , Adult , Aged , Drug Resistance, Fungal , Fungi/drug effects , Antifungal Agents/therapeutic use , Microbial Sensitivity Tests , Fluconazole/therapeutic use , HIV Infections/complications , Amphotericin B/therapeutic use , Itraconazole/therapeutic use , Fungi/isolation & purification , Mycoses/microbiology , Mycoses/drug therapy , Antifungal Agents/pharmacology
6.
Braz. j. biol ; 78(1): 140-146, Feb. 2018. graf
Article in English | LILACS | ID: biblio-888840

ABSTRACT

Abstract The use of chemical defensives to control fungal diseases has by consequence to impact negatively over the environment and human health, this way, the use of plant extracts with antifungal properties along with proper cultural management makes viable an alternative plant production control, specially for familiar and organic cultures. The objective of this study was to perform phytochemical and antioxidant analysis of Byrsonima crassifolia (canjiqueira) barks and evaluate its antifungal potential over Fusarium solani and Sclerotinia sclerotiorum mycelial growth. The ethanol extract from plants collected in Pantanal, Mato Grosso do Sul, Brazil was submitted to phytochemical prospection, total phenol and flavonoids quantification and antioxidant activiy determination (DPPH). To evaluate antifungal activity concentrations of 800, 1200, 1600, 2000 and 2400 µg 100 mL-1 of ethanol extract were used. Which concentration was separately incorporated in agar (PDA) and shed in Petri dishes, followed by the fungi mycelial disc where the colonies diameter was measured daily. Negatives control with agar without extract and agar with an ethanol solution were used. The B. crassifolia ethanol extract presented inhibitory activity over the fungi studied where concentrations of 800 and 1600 µg 100 mL-1, inhibited 38% of the mycelial growth of F. solani; to S. sclerotiorum the best concentration was 2400 µg 100 mL1, reducing 37.5%. The antifungal bark extract potential of this specie is attributed to phenolic compounds and to triterpenes derivatives.


Resumo A aplicação de defensivos químicos para o controle de doenças fúngicas tem por consequência impactos sobre o ambiente e a saúde humana, dessa forma, a utilização de extratos vegetais com propriedades antifúngicas associado ao manejo adequado de culturas, torna-se uma proposta viável de controle alternativo, principalmente na agricultura orgânica e familiar. Neste sentido, objetivou-se neste trabalho realizar a análise fitoquímica e antioxidante das cascas de Byrsonima crassifolia (canjiqueira) e avaliar seu potencial antifúngico sobre o crescimento micelial de Fusarium solani e Sclerotinia sclerotiorum. O extrato etanólico das cascas da planta, coletadas no Pantanal do Rio Negro, em Mato Grosso do Sul, foi submetido à prospecção fitoquímica, quantificação de fenóis totais e flavonoides e determinação da atividade antioxidante (DPPH). Para a avaliação da atividade antifúngica foram utilizadas as concentrações de 800, 1200, 1600, 2000 e 2400 µg 100 mL-1 do extrato etanólico. Cada concentração foi incorporada, separadamente, em ágar BDA, e vertida em placas de petri, seguido do disco de micélio do fungo, onde o diâmetro das colônias foi medido diariamente. Utilizou-se como controle negativo, ágar sem extrato e ágar com solução etanólica. O extrato etanólico de B. crassifolia apresentou atividade inibitória sobre os fungos estudados, onde as concentrações de 800 e 1600 µg 100 mL-1, inibiram 38% do crescimento micelial de F. solani; para S. sclerotiorum, a melhor concentração foi de 2400 µg 100 mL1, com 37,5% de redução de crescimento. Atribui-se o potencial antifúngico do extrato da casca da espécie aos compostos fenólicos e derivados de triterpenos.


Subject(s)
Plant Extracts/chemistry , Malpighiaceae/chemistry , Antifungal Agents/pharmacology , Antifungal Agents/chemistry , Antioxidants/pharmacology , Antioxidants/chemistry , Soil Microbiology , Plant Extracts/pharmacology , Phytochemicals , Fungi/drug effects
7.
Braz. j. microbiol ; 49(supl.1): 205-212, 2018. tab, graf
Article in English | LILACS | ID: biblio-974346

ABSTRACT

Abstract This study compares patients with and without non-viral microbial keratitis in relation to sociodemographic variables, clinical aspects, and involved causative agent. Clinical aspects, etiology and therapeutic procedures were assessed in patients with and without keratitis that were diagnosed in an Eye Care Center in Campo Grande, MS, Brazil. Patients were divided into two groups: (a) cases: 64 patients with non-viral microbial keratitis diagnosed at biomicroscopy; and (b) controls: 47 patients with other eye disorders that were not keratitis. Labor activity related to agriculture, cattle raising, and contact lens use were all linked to keratitis occurrence (p < 0.005). In patients with keratitis, the most common symptoms were pain and photophobia, and the most frequently used medicines were fourth-generation fluoroquinolones (34.4%), amphotericin B (31.3%), and natamycin (28.1%). Microbial keratitis evolved to corneal perforation in 15.6% of cases; transplant was indicated in 10.9% of cases. Regarding the etiology of this condition, 23 (42.2%) keratitis cases were caused by bacteria (Pseudomonas aeruginosa, 12.5%), 17 (39.1%) by fungi (Fusarium spp., 14.1% and Aspergillus spp., 4.7%), and 4 (6.3%) by Acanthamoeba. Patients with keratitis present with a poorer prognosis. Rapid identification of the etiologic agent is indispensable and depends on appropriate ophthalmological collection and microbiological techniques.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Aged , Aged, 80 and over , Young Adult , Bacteria/isolation & purification , Bacterial Infections/microbiology , Fungi/isolation & purification , Keratitis/microbiology , Mycoses/microbiology , Bacteria/classification , Bacteria/drug effects , Bacteria/genetics , Bacterial Infections/drug therapy , Brazil , Fungi/classification , Fungi/drug effects , Fungi/genetics , Keratitis/drug therapy , Middle Aged , Anti-Bacterial Agents/pharmacology , Mycoses/drug therapy , Antifungal Agents/pharmacology
8.
Braz. j. microbiol ; 49(supl.1): 128-139, 2018. tab, graf
Article in English | LILACS | ID: biblio-974327

ABSTRACT

Abstract Pyroligneous extract is applied in diverse areas as an antioxidant, an antimicrobial, and an anti-inflammatory agent. The discovery of new cost-effective antimicrobial agents of natural origin remains a challenge for the scientific community. This study aimed to conduct a systematic review and a technological forecasting of the existent evidence regarding the use of pyroligneous extract as a potential antimicrobial agent. Studies were identified through an investigation of various electronic databases: PubMed, SciFinder, Web of Science, Scopus, Scielo, Google scholar, and ProQuest. Patents were searched through INPI, Google patents, Espacenet, Patents online, USPTO, and WIPO. The literature on antimicrobial activity of pyroligneous extract are limited given the short duration of studies and variability in study design, use of pyroligneous preparations, and reports on results. However, evidence suggests the potential of pyroligneous extract as a natural antimicrobial agent. The most studied activity was the role of PE as a food preservative. However, pyroligneous extracts are also effective against pathogenic bacteria in the oral microflora and treatment of candidal infections. Further research is needed using standardized preparations of pyroligneous extracts to determine their long-term effectiveness and ability as antimicrobial agents.


Subject(s)
Humans , Animals , Wood/chemistry , Plant Extracts/pharmacology , Food Preservatives/pharmacology , Anti-Infective Agents/pharmacology , Bacteria/drug effects , Plant Extracts/chemistry , Food Preservatives/chemistry , Fungi/drug effects , Anti-Infective Agents/chemistry
9.
Rev. chil. infectol ; 34(6): 535-538, dic. 2017. tab, graf
Article in Spanish | LILACS | ID: biblio-899755

ABSTRACT

Resumen Introducción: La infección del torrente sanguíneo es una complicación usual, que puede comprometer la vida de los pacientes que recibieron trasplante de precursores hematopoyéticos. Objetivo: Analizar las características de las infecciones del torrente sanguíneo en receptores de trasplante de precursores hematopoyéticos. Materiales y Métodos: Estudio observacional, retrospectivo. Se revisaron los registros de 451 pacientes (trasplantes autólogos y alogénicos), desde enero de 2009 a octubre de 2015. Resultados: Hubo 99 hemocultivos positivos en 73 pacientes con infección del torrente sanguíneo (16%). Mortalidad atribuible a causas infecciosas: 17%. De las 99 infecciones sanguíneas, 63% fueron provocados por bacilos gramnegativos (Escherichia coli 45%, Klebsiella spp 23%, Pseudomonas spp 11%, Acinetobacter spp 6% y otros bacilos gramnegativos 15%), 33% por cocáceas grampositivas, 3% por hongos y 1% por bacilos grampositivos. Se observó resistencia a ciprofloxacina (81%), piperacilina/tazobactam (48%), Enterobacteriaceae productoras de β-lactamasa de espectro extendido (BLEE) (40%), cefepime (39%) y ausencia de resistencia a amikacina. Discusión: Existe mayor frecuencia de infección por bacilos gramnegativos, con un importante porcentaje de aislados multi-resistentes, y consecuente, alta resistencia al tratamiento antimicrobiano empírico.


Background: Bloodstream infection is a common complication, which can be life-threatening for hematopoietic stem cells transplant recipients. Objective: To analyze the characteristics of bloodstream infections in hematopoietic stem cell transplant recipients. Materials and Methods: Observational, retrospective study. We reviewed the records of 451 patients (autologous and allogeneic transplants) from January 2009 to October 2015. Results: 99 positive blood cultures in 73 patients with bloodstream infection (16%) were found. Mortality attributable to infectious causes was 17%. From the 99 bloodstream infection, 63% were caused by gram-negative bacilli (Escherichia coli 45%, Klebsiella spp 23%, Pseudomonas spp 11% Acinetobacter spp % and other bacilli 15%), 33% by gram-positive cocci, 3% by fungi and 1% by gram-positive bacilli. The gram-negative bacilli were ciprofloxacin resistant (81%), piperacillin/tazobactam resistant (48%), extended-spectrum beta-lactamase (ESBL) producing Enterobacteriaceae (40%), cefepime resistant (39%) and there was no resistance noted to amikacin. Discussion: There is a higher frequency of gram-negative bacilli infection, with a high percentage of multiresistant microorganisms and high resistance to empirical antibiotic treatment.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Young Adult , Fungemia/microbiology , Fungemia/epidemiology , Bacteremia/microbiology , Bacteremia/epidemiology , Hematopoietic Stem Cell Transplantation/adverse effects , Argentina/epidemiology , Bacteria/isolation & purification , Bacteria/drug effects , Drug Resistance, Microbial , Microbial Sensitivity Tests , Retrospective Studies , Fungemia/drug therapy , Bacteremia/drug therapy , Sex Distribution , Age Distribution , Fungi/isolation & purification , Fungi/drug effects , Anti-Bacterial Agents/therapeutic use , Antifungal Agents/therapeutic use
10.
Braz. j. microbiol ; 48(3): 476-482, July-Sept. 2017. tab, graf
Article in English | LILACS | ID: biblio-889147

ABSTRACT

Abstract Onychomycosis is a fungal infection of the nail caused by high densities of filamentous fungi and yeasts. Treatment for this illness is long-term, and recurrences are frequently detected. This study evaluated in vitro antifungal activities of 12 organic compounds derived from amino alcohols against standard fungal strains, such as Trichophyton rubrum CCT 5507 URM 1666, Trichophyton mentagrophytes ATCC 11481, and Candida albicans ATCC 10231. The antifungal compounds were synthesized from p-hydroxybenzaldehyde (4a-4f) and p-hydroxybenzoic acid (9a-9f). Minimum inhibitory concentrations and minimum fungicidal concentrations were determined according to Clinical and Laboratory Standards Institute protocols M38-A2, M27-A3, and M27-S4. The amine series 4b-4e, mainly 4c and 4e compounds, were effective against filamentous fungi and yeast (MIC from 7.8 to 312 µg/mL). On the other hand, the amide series (9a-9f) did not present inhibitory effect against fungi, except amide 9c, which demonstrated activity only against C. albicans. This allowed us to infer that the presence of amine group and intermediate carbon number (8C-11C) in its aliphatic side chain seems to be important for antifungal activity. Although these compounds present cytotoxic activity on macrophages J774, our results suggest that these aromatic compounds might constitute potential as leader molecules in the development of more effective and less toxic analogs that could have considerable implications for future therapies of onychomycosis.


Subject(s)
Humans , Amino Alcohols/pharmacology , Antifungal Agents/pharmacology , Fungi/drug effects , Onychomycosis/microbiology , Amino Alcohols/chemical synthesis , Antifungal Agents/chemical synthesis , Drug Evaluation, Preclinical , Fungi/classification , Fungi/physiology , Microbial Sensitivity Tests , Onychomycosis/drug therapy
11.
Rev. argent. microbiol ; 49(1): 3-6, mar. 2017. ilus, tab
Article in English | LILACS | ID: biblio-1041774

ABSTRACT

Antibiotic resistance results in higher medical costs, prolonged hospital stays and increased mortality and is rising to dangerously high levels in all parts of the world. Therefore, this study aims to search for new antimicrobial agents through bioprospecting of extracts of endophytic fungi from Bauhinia guianensis, a typical Amazonian plant used in combating infections. Seventeen (17) fungi were isolated and as result the methanolic extract of the fungus Exserohilum rostratum showed good activity against the bacteria tested. The polyketide monocerin was isolated by the chromatographic technique, identified by NMR and MS, showing broad antimicrobial spectrum.


La resistencia a los antibióticos conduce a mayores costos médicos, hospitalizaciones prolongadas e incremento de la mortalidad, y está aumentando a niveles peligrosamente altos en todas partes del mundo. Este estudio tuvo como objetivo la búsqueda de nuevos agentes antimicrobianos a través de la bioprospección de extractos de hongos endófitos de Bauhinia guianensis, una planta amazónica típica, utilizada en la lucha contra problemas infecciosos. Fueron aislados 17 hongos; el extracto metanólico del hongo Exserohilum rostratum mostró buena actividad contra las bacterias probadas. Se aisló monocerina policétido por la técnica de cromatografía; este compuesto fue identificado por RM y EM, y mostró un amplio espectro antimicrobiano.


Subject(s)
Bauhinia/microbiology , Endophytes/isolation & purification , Polyketides/isolation & purification , Fungi/drug effects , Anti-Infective Agents/analysis , Anti-Bacterial Agents/analysis , Drug Resistance, Microbial/drug effects , Chromatography/methods , Bioprospecting/methods
12.
Braz. j. microbiol ; 47(4): 917-924, Oct.-Dec. 2016. tab, graf
Article in English | LILACS | ID: biblio-828189

ABSTRACT

Abstract This study aimed to evaluate the in vitro antifungal activity of terpinen-4-ol, tyrosol, and β-lapachone against strains of Coccidioides posadasii in filamentous phase (n = 22) and Histoplasma capsulatum in both filamentous (n = 40) and yeast phases (n = 13), using the broth dilution methods as described by the Clinical and Laboratory Standards Institute, to determine the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of these compounds. The mechanisms of action of these compounds were also investigated by analyzing their effect on cell membrane permeability and ergosterol synthesis. The MIC and MFCf these compounds against C. posadasii, mycelial H. capsulatum, and yeast-like H. capsulatum, were in the following ranges: 350-5720 µg/mL, 20-2860 µg/mL, and 40-1420 µg/mL, respectively for terpinen-4-ol; 250-4000 µg/mL, 30-2000 µg/mL, and 10-1000 µg/mL, respectively, for tyrosol; and 0.48-7.8 µg/mL, 0.25-16 µg/mL, and 0.125-4 µg/mL, respectively for β-lapachone. These compounds showed a decrease in MIC when the samples were subjected to osmotic stress, suggesting that the compounds acted on the fungal membrane. All the compounds were able to reduce the ergosterol content of the fungal strains. Finally, tyrosol was able to cause a leakage of intracellular molecules.


Subject(s)
Phenylethyl Alcohol/analogs & derivatives , Terpenes/pharmacology , Naphthoquinones/pharmacology , Fungi/drug effects , Antifungal Agents/pharmacology , Osmotic Pressure , Phenylethyl Alcohol/pharmacology , Microbial Sensitivity Tests , Cell Membrane Permeability/drug effects , Ergosterol/metabolism , Fungi/classification , Fungi/metabolism
13.
Braz. j. microbiol ; 47(4): 793-799, Oct.-Dec. 2016. tab
Article in English | LILACS | ID: biblio-828190

ABSTRACT

Abstract Triazole fungicides are used broadly for the control of infectious diseases of both humans and plants. The surge in resistance to triazoles among pathogenic populations is an emergent issue both in agriculture and medicine. The non-rational use of fungicides with site-specific modes of action, such as the triazoles, may increase the risk of antifungal resistance development. In the medical field, the surge of resistant fungal isolates has been related to the intensive and recurrent therapeutic use of a limited number of triazoles for the treatment and prophylaxis of many mycoses. Similarities in the mode of action of triazole fungicides used in these two fields may lead to cross-resistance, thus expanding the spectrum of resistance to multiple fungicides and contributing to the perpetuation of resistant strains in the environment. The emergence of fungicide-resistant isolates of human pathogens has been related to the exposure to fungicides used in agroecosystems. Examples include species of cosmopolitan occurrence, such as Fusarium and Aspergillus, which cause diseases in both plants and humans. This review summarizes the information about the most important triazole fungicides that are largely used in human clinical therapy and agriculture. We aim to discuss the issues related to fungicide resistance and the recommended strategies for preventing the emergence of triazole-resistant fungal populations capable of spreading across environments.


Subject(s)
Humans , Triazoles/poisoning , Ecosystem , Drug Resistance, Fungal , Agriculture , Fungi/drug effects , Antifungal Agents/pharmacology , Plant Diseases/microbiology , Triazoles/therapeutic use , Fungi/physiology , Fungicides, Industrial , Mycoses/microbiology , Mycoses/drug therapy , Antifungal Agents/therapeutic use
14.
Electron. j. biotechnol ; 19(6): 70-78, Nov. 2016. ilus
Article in English | LILACS | ID: biblio-840316

ABSTRACT

Background: Many buildings in Egypt e.g. museums, mosques and churches, do not possess controlled environments for minimizing the risks of damage of wooden artifacts due to the growth of fungi. Fungal damage usually appears as change in wood color, appearance of stains, and sometimes deformation of wooden surfaces. In this study we focused on the effect that some fungi exert on the properties of wooden artifacts and evaluated the effectiveness of different concentrations of chitosan on their protection against damage by mold fungi. Results: Samples were collected from different monuments and environments, and fungi growing on them were isolated and identified. The isolated Penicillium chrysogenum, Aspergillus flavus and /Aspergillus niger strains were used for the infestation of new pitch pine samples. The results revealed that the lightness of samples infected with any of the tested fungi decreased with increasing incubation times. XRD analysis showed that the crystallinity of incubated samples treated individually with the different concentrations of chitosan was lower than the crystallinity of infected samples. The crystallinity index measured by the first and the second method decreased after the first and second months but increased after the third and fourth months. This may due to the reducing of amorphous part by enzymes or acids produced by fungi in wooden samples. Conclusions: The growth of fungi on the treated wood samples decreased with increasing the concentration of chitosan. Hence, it was demonstrated that chitosan prevented fungal growth, and its use could be recommended for the protection of archeological wooden artifacts.


Subject(s)
Antifungal Agents/pharmacology , Chitosan/chemistry , Fungi/drug effects , Wood/microbiology , Archaeology , Aspergillus flavus/drug effects , Aspergillus flavus/isolation & purification , Aspergillus niger/drug effects , Aspergillus niger/isolation & purification , Chitosan/pharmacology , Crystallization , Penicillium chrysogenum/drug effects , Penicillium chrysogenum/isolation & purification , Spectrophotometry, Ultraviolet
15.
Braz. j. microbiol ; 47(2): 480-488, Apr.-June 2016. tab, graf
Article in English | LILACS | ID: lil-780842

ABSTRACT

Abstract The aim of this paper is to identify and investigate an endophytic fungus (strain 28) that was isolated from Houttuynia cordata Thunb, a famous and widely-used Traditional Chinese Medicine. Based on morphological methods and a phylogenetic analysis of ITS sequences, this strain was identified as Chaetomium globosum. An antifungal activity bioassay demonstrated that the crude ethyl acetate (EtOAc) extracts of strain 28 had a wide antifungal spectrum and strong antimicrobial activity, particularly against Exserohilum turcicum (Pass.) Leonard et Suggs, Botrytis cinerea persoon and Botrytis cinerea Pers. ex Fr. Furthermore, the fermentation conditions, extraction method and the heat stability of antifungal substances from strain 28 were also studied. The results showed that optimal antifungal activity can be obtained with the following parameters: using potato dextrose broth (PDB) as the base culture medium, fermentation for 4–8 d (initial pH: 7.5), followed by extraction with EtOAc. The extract was stable at temperatures up to 80 °C. This is the first report on the isolation of endophytic C. globosum from H. cordata to identify potential alternative biocontrol agents that could provide new opportunities for practical applications involving H. cordata.


Subject(s)
Chaetomium/isolation & purification , Chaetomium/metabolism , Houttuynia/microbiology , Endophytes/metabolism , Antifungal Agents/metabolism , Phylogeny , Chaetomium/classification , Chaetomium/genetics , Endophytes/isolation & purification , Endophytes/classification , Endophytes/genetics , Fungi/growth & development , Fungi/drug effects , Antifungal Agents/pharmacology
16.
Braz. j. microbiol ; 46(4): 1103-1110, Oct.-Dec. 2015. tab, graf
Article in English | LILACS | ID: lil-769653

ABSTRACT

Abstract We evaluated the antimicrobial activity of Aspilia latissima - an abundant plant from the Brazilian Pantanal region - against Candida albicans, Candida parapsilosis, Candida krusei, Candida tropicalis, Pseudomonas aeruginosa, Enterococcus faecalis, Escherichia coli and Staphylococcus aureus. The crude extracts and fractions showed activity in all tested microorganisms. The chloroform fraction of the leaves and roots showed the most antimicrobial activity against S. aureus, with an MIC of 500 μg/mL. This fraction was submitted to bioautographic assays to characterize the activity of the compounds. Two bands from the leaves (L-A and L-B) and three bands from the roots (R-C, R-D and R-E) were bioactive. Within the root-derived bands, the terpene derivatives stigmasterol, kaurenoic acid and kaura-9(11), 16-dien-18-oic acid were identified. Antibiotic activity of A. latissima is reported for the first time.


Subject(s)
Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/drug effects , Anti-Bacterial Agents/pharmacology , Antifungal Agents/chemistry , Antifungal Agents/drug effects , Antifungal Agents/pharmacology , Asteraceae/chemistry , Asteraceae/drug effects , Asteraceae/pharmacology , Bacteria/chemistry , Bacteria/drug effects , Bacteria/pharmacology , Brazil/chemistry , Brazil/drug effects , Brazil/pharmacology , Fungi/chemistry , Fungi/drug effects , Fungi/pharmacology , Gas Chromatography-Mass Spectrometry/chemistry , Gas Chromatography-Mass Spectrometry/drug effects , Gas Chromatography-Mass Spectrometry/pharmacology , Microbial Sensitivity Tests/chemistry , Microbial Sensitivity Tests/drug effects , Microbial Sensitivity Tests/pharmacology , Plant Extracts/chemistry , Plant Extracts/drug effects , Plant Extracts/pharmacology , Plant Leaves/chemistry , Plant Leaves/drug effects , Plant Leaves/pharmacology , Plant Roots/chemistry , Plant Roots/drug effects , Plant Roots/pharmacology
17.
Rev. Inst. Med. Trop. Säo Paulo ; 57(5): 397-405, Sept.-Oct. 2015. tab, graf
Article in English | LILACS | ID: lil-766279

ABSTRACT

SUMMARY In this study, the bioactivity of Talinum paniculatum was evaluated, a plant widely used in folk medicine. The extract from the T. paniculatum leaves (LE) was obtained by percolation with ethanol-water and then subjecting it to liquid-liquid partitions, yielding hexane (HX), ethyl acetate (EtOAc), butanol (BuOH), and aqueous (Aq) fractions. Screening for antimicrobial activity of the LE and its fractions was evaluated in vitro through broth microdilution method, against thirteen pathogenic and non-pathogenic microorganisms, and the antimycobacterial activity was performed through agar diffusion assay. The cytotoxic concentrations (CC90) for LE, HX, and EtOAc were obtained on BHK-21 cells by using MTT reduction assay. The LE showed activity against Serratia marcescens and Staphylococcus aureus, with Minimum Inhibitory Concentration (MIC) values of 250 and 500 µg/mL, respectively. Furthermore, HX demonstrated outstanding activity against Micrococcus luteus and Candida albicans with a MIC of 31.2 µg/mL in both cases. The MIC for EtOAc also was 31.2 µg/mL against Escherichia coli. Conversely, BuOH and Aq were inactive against all tested microorganisms and LE proved inactive against Mycobacterium tuberculosisand Mycobacterium bovisas well. Campesterol, stigmasterol, and sitosterol were the proposed structures as main compounds present in the EF and HX/EtOAc fractions, evidenced by mass spectrometry. Therefore, LE, HX, and EtOAc from T. paniculatumshowed potential as possible sources of antimicrobial compounds, mainly HX, for presenting low toxicity on BHK-21 cells with excellent Selectivity Index (SI = CC90/MIC) of 17.72 against C. albicans.


RESUMO Neste estudo foi avaliada a bioatividade de Talinum paniculatum, planta amplamente utilizada na medicina popular. O extrato das folhas (EF) de T. paniculatum foi obtido por percolação com etanol-água e, em seguida, submetido à partição líquido-líquido, obtendo-se as frações hexânica (HX), acetato-etílica (AcOEt), butanólica (BuOH) e aquosa (Aq). A triagem para a atividade antimicrobiana do EF e de suas frações foram avaliadas in vitro através do método de microdiluição em caldo contra treze micro-organismos patogênicos e não-patogênicos e, a atividade antimicobacteriana, foi avaliada através do teste de difusão em ágar. As concentrações citotóxicas (CC90) do EF e das frações HX e AcOEt foram obtidas sobre células da linhagem BHK-21 através do ensaio de redução do MTT. O EF mostrou atividade contra Serratia marcescens e Staphylococcus aureus, com valores de concentração inibitória mínima (CIM) de 250 e 500 µg/mL, respectivamente. Além disso, HX demonstrou excelente atividade contra Micrococcus luteus e Candida albicans com uma CIM de 31,2 µg/mL, em ambos os casos. Contra Escherichia coli, a CIM para AcOEt foi também de 31,2 µg/mL. Por outro lado, as frações BuOH e Aq foram inativas contra todos os micro-organismos testados, assim como o EF contra Mycobacterium tuberculosis e Mycobacterium bovis. Campesterol, estigmasterol e sitosterol foram as estruturas propostas como principais compostos presentes no EF e nas frações HX e AcOEt, evidenciadas através de espectrometria de massas. Portanto, o extrato da folha e as frações HX e AcOEt provenientes de T. paniculatum apresentaram potencial como possíveis fontes de compostos antimicrobianos, HX principalmente, por ter apresentado uma baixa toxicidade sobre células BHK-21 com um bom índice de seletividade (IS = CC90/MIC) de 17,72 contra C. albicans.


Subject(s)
Anti-Bacterial Agents/pharmacology , Antifungal Agents/pharmacology , Caryophyllaceae/chemistry , Fungi/drug effects , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Plant Extracts/pharmacology , Fungi/classification , Gram-Negative Bacteria/classification , Gram-Positive Bacteria/classification , Microbial Sensitivity Tests
18.
Braz. j. microbiol ; 46(2): 359-366, Apr-Jun/2015. tab, graf
Article in English | LILACS | ID: lil-749714

ABSTRACT

Endophytes are being considered for use in biological control, and the enzymes they secrete might facilitate their initial colonization of internal plant tissues and direct interactions with microbial pathogens. Microbial proteases are also biotechnologically important products employed in bioremediation processes, cosmetics, and the pharmaceutical, photographic and food industries. In the present study, we evaluated antagonism and competitive interactions between 98 fungal endophytes and Alternaria alternata, Colletotrichum sp., Phyllosticta citricarpa and Moniliophthora perniciosa. We also examined the proteolytic activities of endophytes grown in liquid medium and conducted cup plate assays. The results showed that certain strains in the assemblage of P. hispidum endophytes are important sources of antifungal properties, primarily Lasiodiplodia theobromae JF766989, which reduced phytopathogen growth by approximately 54 to 65%. We detected 28 endophytes producing enzymatic halos of up to 16.40 mm in diameter. The results obtained in the present study highlight the proteolytic activity of the endophytes Phoma herbarum JF766995 and Schizophyllum commune JF766994, which presented the highest enzymatic halo diameters under at least one culture condition tested. The increased activities of certain isolates in the presence of rice or soy flour as a substrate (with halos up to 17.67 mm in diameter) suggests that these endophytes have the potential to produce enzymes using agricultural wastes.


Subject(s)
Antifungal Agents/metabolism , Endophytes/isolation & purification , Endophytes/metabolism , Fungi/isolation & purification , Fungi/metabolism , Peptide Hydrolases/metabolism , Piper/microbiology , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Ribosomal Spacer/chemistry , DNA, Ribosomal Spacer/genetics , Fungi/classification , Fungi/drug effects , Microbiological Techniques , Molecular Sequence Data , Sequence Analysis, DNA
19.
Braz. j. microbiol ; 46(1): 139-143, 05/2015. tab, graf
Article in English | LILACS | ID: lil-748240

ABSTRACT

The present investigations were aimed to evaluate the antimicrobial and antioxidant efficacies of budmunchiamine-A (BUA) of Albizia amara. The activity-guided isolation leaded to isolate the bioactive compound budmunchiamine-A from alkaloid extract of A. amara. The budmunchiamine-A showed significant broad-spectrum antimicrobial activity with zone of inhibition (ZOI), minimum inhibitory concentration (MIC) and minimum bactericidal/fungicidal concentration (MBC/MFC) values varied from 7.3 to 24.5 mm, 0.95 to 62.5 μg/mL, and 1.9 to 250 μg/mL, respectively. The budmunchiamine-A exhibited moderate antioxidant activity with inhibitory concentration 50% (IC50) value of 400 μg/mL in 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and percent inhibition of β-carotene/linoleic acid was 67.8%. The results suggest the possible use of budmunchiamine-A as a molecular entity for drug development in pharmaceutical industry.


Subject(s)
Albizzia/chemistry , Anti-Infective Agents/pharmacology , Antioxidants/pharmacology , Plant Extracts/pharmacology , Anti-Infective Agents/isolation & purification , Antioxidants/isolation & purification , Bacteria/drug effects , Fungi/drug effects , Microbial Sensitivity Tests , Microbial Viability/drug effects , Plant Extracts/isolation & purification
20.
Braz. j. microbiol ; 46(1): 189-194, 05/2015. tab
Article in English | LILACS | ID: lil-748257

ABSTRACT

This study had analyzed the antibacterial, antifungal and trypanocidal activity of the essential oils from Cinnamodendron dinisii Schwacke (Canellaceae) and Siparuna guianensis Aublet (Siparunaceae). The essential oils were obtained from fresh leaves by hydrodistillation, using a modified Clevenger apparatus. Chemical analysis by gas-liquid chromatography coupled to mass spectrometry (GC-MS) showed that these essential oils are rich in monoterpene and sesquiterpene hydrocarbons. Activity against the pathogenic bacteria Escherichia coli, Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella choleraesuis and Staphylococcus aureus was evaluated with the agar cavity diffusion method, while activity on the filamentous fungi Aspergillus flavus, Aspergillus niger, Aspergillus carbonarius and Penicillium commune was evaluated by the disk diffusion technique. Trypanocidal activity was tested against Trypanosoma cruzi epimastigotes, using the Tetrazolium salt (MTT) colorimetric assay. Both essential oils exhibited low inhibitory effect towards bacteria, showing high MIC values (125–500 μg mL−1), with Gram positive bacteria being more susceptible. Better inhibitory effect was obtained for the evaluated fungi, with lower MIC values (7.81–250 μg mL−1), being A. flavus the most susceptible species. Both essential oils presented low trypanocidal activity, with IC50/24 h values of 209.30 μg mL−1 for S. guianensis and 282.93 μg mL−1 for C. dinisii. Thus, the high values observed for the MIC of evaluated bacteria and for IC50/24 h of T. cruzi, suggest that the essential oils have a low inhibitory activity against these microorganisms. In addition, the low MIC values observed for the tested fungi species indicate good inhibitory activity on these microorganisms’s growth.


Subject(s)
Magnoliopsida/chemistry , Anti-Infective Agents/pharmacology , Bacteria/drug effects , Fungi/drug effects , Oils, Volatile/pharmacology , Trypanosoma cruzi/drug effects , Anti-Infective Agents/isolation & purification , Microbial Sensitivity Tests , Oils, Volatile/isolation & purification
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