ABSTRACT
This review describes the geographical distribution, botanical data, popular use, chemical composition, pharmacological activities and genetic aspects related to Eugenia luschnathiana, a native Brazilian plant popularly known as "bay pitomba". E. luschnathiana leaves are characterized morphologically by the presence of a petiole, an attenuated base, acuminated apex, elliptical shape, and parallel venation. The major chemical compounds found in E. luschnathiana are sesquiterpenes. Literature reports showed that E. luschnathiana extracts have antioxidant properties and antimicrobial activity against Gram-negative and Gram-positive bacteria. The extractsfrom the leaf, fruit and stem, and a concentrated residual solution of its essential oil, displayed negligible toxicity. Lastly, a cytogenetic analysis indicated that some markers can be used for the study of genetic diversity, population structure, and genetic improvements. The information available on E. luschnathiana supports the hypothesis that this plant may be a source of compounds with promising pharmacological activity.
Esta revisión describe la distribución geográfica, datos botánicos, uso popular, composición química, actividad farmacológica y el análisis genético de Eugenia luschnathiana, una planta originaria del Brasil conocida popularmente como "pitomba da baía". Las hojas de E. luschnathiana se caracterizan por la presencia de pecíolo, base atenuada, ápice acuminado, forma elíptica y venación paralela. Su composición química presenta mayormente sesquiterpenos. Los informes en la literatura muestran que los extractos de E. luschnathiana presentan propiedades antioxidantes y actividad antimicrobiana contra las bacterias Gram-negativas y Gram-positivas. Los extractos de la hoja, fruto y tallo, y una solución residual concentrada del aceite esencial, presentaron baja toxicidad. Por último, un análisis citogenético indicó que algunos marcadores pueden utilizarse para estudios de diversidad genética, estructura poblacional y mejoramiento genético. Las informaciones disponibles acerca de E. luschnathiana proponen la hipótesis de que esta planta puede ser una fuente de compuestos con actividad farmacológica prometedora.
Subject(s)
Oils, Volatile/pharmacology , Plant Extracts/pharmacology , Eugenia/chemistry , Anti-Infective Agents/pharmacology , Terpenes/analysis , Bacteria/drug effects , Oils, Volatile/chemistry , Plant Extracts/genetics , Plant Extracts/chemistry , Plant Leaves/chemistry , Eugenia/genetics , Medicine, Traditional , Anti-Infective Agents/chemistryABSTRACT
This paper described the chemical compositions and antimicrobial activity of the essential oils from the leaves and stem of Amomum rubidumLamxay & N. S. Lý, collected from Bidoup Nui Ba National Park, Lam Dong, Vietnam. The essential oils were obtained by hydrodisitllation method while antimicrobial activity was evaluetd by microdilution broth susceptibility assay. The main constituents of the leaf essential oil were identified as 1,8-cineole (37.7%), δ-3-carene (19.5%) and limonene (16.3%) while δ-3-carene (21.9%), limonene (17.8%) and ß-phellandrene (14.6%) dominated in the stem essentialoil. The leaf and stem essential oils displayed stronger inhibition of Pseudomonas aeruginosa with MIC of 25 µg/mLand 50 µg/mL respectively. The stem essential oil was active against Candida albicans (MIC, 50 µg/mL) while both essential oils inhibited the growth of Fusarium oxysporum (MIC 50 µg/mL). This is the first report on chemical constituents and antimicrobial activity of the essential oils of A. rubidum.
Este artículo describe la composición química y la actividad antimicrobiana de aceites esenciales de las hojas y el tallo de Amomum rubidum Lamxay & N. S. Lý recolectados del Parque Nacional Bidoup Nui Ba, Lam Dong, Vietnam. Los aceites esenciales se obtuvieron mediante el método de hidrodisitilación, mientras que la actividad antimicrobiana se evaluó mediante un ensayo de susceptibilidad de caldo de microdilución. Los principales componentes del aceite esencial de la hoja se identificaron como 1,8-cineol (37,7%), δ-3-careno (19,5%) y limoneno (16,3%), mientras que δ-3-careno (21,9%), limoneno (17,8 %) y ß-felandreno (14,6%) dominaron en el aceite esencial del tallo. Los aceites esenciales de hoja y tallo mostraron una inhibición más fuerte de Pseudomonas aeruginosa con un MIC de 25 µg/mL y 50 µg/mL, respectivamente. El aceite esencial del tallo fue activo contra Candida albicans (MIC, 50 µg/mL) mientras que ambos aceites esenciales inhibieron el crecimiento de Fusarium oxysporum (MIC 50 µg/mL). Este es el primer informe sobre los componentes químicos y la actividad antimicrobiana de los aceites esenciales de A. rubidum.
Subject(s)
Oils, Volatile/pharmacology , Amomum/chemistry , Anti-Infective Agents/pharmacology , Pseudomonas aeruginosa/drug effects , Candida albicans/drug effects , Oils, Volatile/chemistry , Microbial Sensitivity Tests , Distillation , Chromatography, Gas , Plant Stems , Plant Leaves , Monoterpenes/analysis , Fusarium/drug effects , Anti-Infective Agents/chemistryABSTRACT
Propolis is a substance manufactured by Apis mellifera and has been widely used in folk medicine due to its high concentration of bioactive compounds. The purpose of the following study was to characterize and evaluate in vitro the antimicrobial properties of propolis on clinical samples and ATCC strains. The chemical characterization of propolis presents a concentration of total polyphenols of 247 ± 9 mg EAG g-1 MS, flavones and flavonols 75± 4 mg EQ g-1 MS, flavanonones and flavanonols 118 ± 11 EP g-1 MS. HPLC-DAD identified apigenin, galangin, phenethyl ester of caffeic acid and pinocembrin, in addition to 16 compounds by HPLC MS/MS. Chilean propolis is a natural antimicrobial, showing effectiveness in strains ATCC Staphylococcus aureus, Candida albicans, Trichophyton rubrum and clinical samples of Staphylococcus aureus unlike Escherichia coli. These results demonstrate the antimicrobial effectiveness of the synergy of compounds present in propolis against different human pathogens.
El propoÌleos es una substancia fabricada por Apis mellifera y ha sido utilizado ampliamente en la medicina popular debido a su alta concentracioÌn de compuestos bioactivos. El propoÌsito del siguiente estudio fue caracterizar y evaluar in vitro las propiedades antimicrobianas del propoÌleos sobre muestras cliÌnicas y cepas ATCC. La caracterizacioÌn quiÌmica de propoÌleos presenta una concentracioÌn de polifenoles totales de 247 ± 9 mg EAG g-1 de MS, flavonas y flavonoles 75 ± 4 mg EQ g-1 de MS, flavanononas y flavanonoles 118 ± 11 EP g-1 de MS. Mediante HPLC-DAD se identificoÌ apigenina, galangina, fenetil eÌster del aÌcido cafeico y pinocembrina, ademaÌs de 16 compuestos mediante HPLC MS/MS. El propoÌleos chileno es un antimicrobiano natural, observaÌndose efectividad en cepas ATCC Staphylococcus aureus, Candida albicans, Trichophyton rubrum y muestras cliÌnicas de Staphylococcus aureus a diferencia de Escherichia coli. Estos resultados demuestran la efectividad antimicrobiana de la sinergia de compuestos presentes en el propoÌleos ante diferentes patoÌgenos humanos.
Subject(s)
Humans , Propolis/pharmacology , Staphylococcus aureus/drug effects , Candida albicans/drug effects , Escherichia coli/drug effects , Anti-Infective Agents/pharmacology , Pharynx/microbiology , Propolis/chemistry , Trichophyton/drug effects , Flavonoids/analysis , Microbial Sensitivity Tests , Apis mellifica , Chile , Chromatography, High Pressure Liquid , Escherichia coli/drug effects , Gas Chromatography-Mass Spectrometry , Anti-Infective Agents/chemistry , Mouth/microbiologyABSTRACT
Abstract The main objective of this study was to demonstrate the antimicrobial potential of the crude extract and fractions of Chenopodium ambrosioides L., popularly known as Santa-Maria herb, against microorganisms of clinical interest by the microdilution technique, and also to show the chromatographic profile of the phenolic compounds in the species. The Phytochemical screening revealed the presence of cardiotonic, anthraquinone, alkaloids, tannins and flavonoids. The analysis by HPLC-DAD revealed the presence of rutin in the crude extract (12.5 ± 0.20 mg/g), ethyl acetate (16.5 ± 0.37 mg/g) and n-butanol (8.85 ± 0.11 mg/g), whereas quercetin and chrysin were quantified in chloroform fraction (1.95 ± 0.04 and 1.04 ± 0.01 mg/g), respectively. The most promising results were obtained with the ethyl acetate fraction, which inhibited a greater number of microorganisms and presented the lowest values of MIC against Staphylococcus aureus and Enterococcus faecalis (MIC = 0.42 mg/mL), Pseudomonas aeruginosa (MIC = 34.37 mg/mL), Paenibacillus apiarus (MIC = 4.29 mg/mL) and Paenibacillus thiaminolyticus (MIC = 4.29 mg/mL). Considering mycobacterial inhibition, the best results were obtained by chloroform fraction against M. tuberculosis, M. smegmatis, and M. avium (MIC ranging from 156.25 to 625 µg/mL). This study proves, in part, that the popular use of C. ambrosioides L. can be an effective and sustainable alternative for the prevention and treatment of diseases caused by various infectious agents.
Subject(s)
Anti-Infective Agents/pharmacology , Bacteria/drug effects , Chenopodium ambrosioides/chemistry , Phenols/pharmacology , Phytochemicals/pharmacology , Plant Extracts/pharmacology , Anti-Infective Agents/chemistry , Anti-Infective Agents/isolation & purification , Chromatography, High Pressure Liquid , Drug Evaluation, Preclinical , Microbial Sensitivity Tests , Phenols/chemistry , Phenols/isolation & purification , Phytochemicals/chemistry , Phytochemicals/isolation & purification , Plant Extracts/chemistry , Plant Extracts/isolation & purificationABSTRACT
Abstract The essential oils are extracted from plant compounds and can present activities antimicrobial and antioxidant properties. The goals of the present study were: (a) to determine the chemical composition of the essential oil of Guarea kunthiana A. Juss using the method of gas chromatography coupled to mass spectrometry (GC-MS); (b) to evaluate the antimicrobial potential of this oil using the broth microdilution method against different microorganisms: five Gram-negative bacteria, four Gram-positive bacteria and a yeast and (c) to determine the antioxidant activity of the oil using the DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical assay. The GC-MS analyses allowed identifying 13 constituents, representing 96.52% of the essencial oil composition. The main compounds identified were α-zingiberene (34.48%), β-sesquiphellandrene (22.90%), and α-curcumene (16.17%). With respect to the antimicrobial activity, the essential oil was effective against all the microorganisms tested, except for the bacteria E. coli and K. pneumoniae, which were resistant to the action of the oil. From a general point of view, Gram-positive bacteria were more susceptible to the action of the essential oil than Gram-negative bacteria. The essential oil exhibited antioxidant potential.
Resumo Os óleos essenciais são compostos extraídos de plantas e podem apresentar propriedades antimicrobianas e antioxidantes. O objetivo deste trabalho foi (a) determinar a composição química do óleo essencial de Guarea kunthiana A. Juss pelo método de cromatografia gasosa acoplada à espectrometria de massas (CG-EM); (b) avaliar o potencial antimicrobiano deste óleo pelo método de microdiluição em caldo frente a diferentes micro-organismos, sendo cinco bactérias Gram-negativas, quatro Gram-positivas uma levedura e (c) por fim, determinar a atividade antioxidante do óleo pelo método de captura do radical livre 2,2-difenil-1-picril hidrazil (DPPH). As análises de CG-EM resultaram na identificação de 13 constituintes, representando 96,52% da composição do óleo essencial. Os principais compostos identificados foram α-Zingibereno (34,48%), β-Sesquifelandreno (22,90%) e α-Curcumeno (16,17%). Em relação à atividade antimicrobiana, o óleo essencial foi efetivo frente a todos os micro-organismos testados exceto para as bactérias E. coli e K. pneumoniae, as quais se apresentaram resistentes à ação do óleo. Em geral, as bactérias Gram-positivas foram mais suscetíveis à ação do óleo essencial em relação às Gram-negativas. O óleo essencial apresentou potencial.
Subject(s)
Oils, Volatile/pharmacology , Oils, Volatile/chemistry , Meliaceae/chemistry , Anti-Infective Agents/pharmacology , Anti-Infective Agents/chemistry , Antioxidants/pharmacology , Antioxidants/chemistry , Picrates , Bacteria/drug effects , Biphenyl CompoundsABSTRACT
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/chemistryABSTRACT
Serum protein concentrations, including acute phase proteins (APPs), of goats and ewes with naturally acquired Sthaphylococcus aureus mastitis were determined by means of SDS-PAGE electrophoresis to evaluate the relevance of these APPs as biomarkers of the disease in these species. Fifteen healthy goats and 5 goats with naturally acquired staphylococci mastitis, as well as fifteen healthy ewes and 5 ewes with staphylococci mastitis were submitted to daily blood sampling during 7 days. In goats, an increase of 570%, 125%, 621%, and 279% in serum concentrations of ceruloplasmin, fibrinogen, haptoglobin and α1-acid glycoprotein, respectively, was observed. In sheep the increase in serum concentrations of ceruloplasmin, fibrinogen, haptoglobin and α1-acid glycoprotein was of 337%, 90%, 461%, and 225%, respectively. Our results indicate that these APPs have considerable potencial as early and sensible biomarkers of mastitis caused by S. aureus in goats and sheep.(AU)
O proteinograma, incluindo proteínas de fase aguda (PFAs), de cabras e ovelhas com mastite de origem natural causada por Staphylococcus aureus, foi determinado por meio de eletroforese em gel de poliacrilamida contendo dodecil sulfato de sódio (SDS-PAGE) a fim de avaliar a importância destas PFAs como biomarcadores da enfermidade nestas espécies. Amostras de sangue foram colhidas diariamente de cinco cabras e cinco ovelhas com mastite estafilocócica naturalmente adquirida, bem como de quinze cabras e quinzes ovelhas saudáveis durante 6 dias consecutivos. Nas fêmeas caprinas, foi verificado aumento dos teores séricos de ceruloplasmina (570%), fibrinogênio (125%), haptoglobina (621%), e α1-glicoproteína ácida (279%). Nas fêmeas ovinas as concentrações de ceruloplasmina, fibrinogênio, haptoglobina e α1-glicoproteína ácida elevaram-se em 337%, 90,9%, 461% e 225%, respectivamente. Os resultados permitem inferir que estas PFAs são marcadores sensíveis e precoces de mastite causada por S. aureus em cabras e ovelhas.(AU)
Subject(s)
Animals , Female , Acute-Phase Proteins/analysis , Anti-Infective Agents/chemistry , Goats/virology , Mastitis/veterinary , Sheep/virology , Staphylococcus aureus , Ceruloplasmin/analysis , Electrophoresis, Polyacrylamide Gel/veterinary , Fibrinogen/analysis , Haptoglobins/analysis , Orosomucoid/analysisABSTRACT
Abstract The development of a biodegradable material with antimicrobial properties for local applications is required in the prevention and treatment of infectious diseases. The objective of this study was to produce blends of poly-L-lactide acid (PLLA) synthetic polymer associated with several antimicrobials, as an alternative in the prevention and treatment of infections, as well as to evaluate its cytotoxicity, release of antimicrobials and inhibit bacteria growth. Blends of PLLA added with 20% Amoxicillin, Metronidazole, Clindamycin or Azithromicyn were used to produce Films (F) or Meshs (M) by casting and electrospinning methods, respectively. Standardized discs of the films and meshs were stored in buffer solutions (pH 5 or 7.4) and aliquots were analyzed by high performance chromatography (HPLC) during 168 hours. Cytotoxicity on human gingival fibroblasts was tested after 24, 48 and 72h by MTT reaction. The antimicrobial capacity was determined against P. gingivalis and S. pyogenes. The specimens were weighed after 3 and 6 months of storage for degradation analysis. SEM was performed to control interfaces and degradation. Antimicrobials presented a continuous and exponential drug release. Analysis showed that both M and F were able to inhibit S. pyogenes and P. gingivalis growth, indicating the release of active antimicrobial agents. The products were not toxic to the fibroblasts. Amoxicillin-film showed more degradation than PLLA at both pHs (p < 0.05), whereas Azithromycin-meshes were more degraded than PLLA at pH 7.4 (p < 0.05). PLLA association with antimicrobials is biocompatible and may represent a potential tool for the local delivery of antimicrobials.
Subject(s)
Humans , Polyesters/pharmacology , Polymers/pharmacology , Streptococcus pyogenes/drug effects , Biocompatible Materials/pharmacology , Porphyromonas gingivalis/drug effects , Microbial Viability/drug effects , Anti-Infective Agents/pharmacology , Polymers/chemistry , Surgical Mesh/adverse effects , Biocompatible Materials/chemistry , Materials Testing , Cell Culture Techniques , Drug Combinations , Anti-Infective Agents/chemistryABSTRACT
Background: Biofilm infections are a major challenge in medical practice. Bacteria that live in a biofilm phenotype are more resistant to both antimicrobial therapy and host immune responses compared to their planktonic counterparts. So, there is need for new therapeutic strategies to combat these infections. A promising approach [known as Photodynamic Inactivation [PDI]] to kill bacteria growing as biofilms uses light in combination with a photosensitizer to induce a phototoxic reaction which produces reactive oxygen species that can destroy lipids and proteins causing cell death. PDI does not always guarantee full success, so, combination of PDI with antibiotics may give increased efficiency. This study aimed to determine if PDI was effective in the eradication of Staphylococcus aureus [S. aureus] biofilms in combination with linezolid
Methods: The susceptibility of biofilm cultures of three S. aureus strains to Methylene Blue [MB] and Toluidine Blue O [TBO]-mediated PDI was determined alone and in combination with linezolid
Results: Bactericidal activity [>/=3 log[10] reduction in viable cell count] was not achieved with MB/TBO-PDI or antibiotic treatment alone. When antibiotic treatment was combined with TBO-PDI, a greater reduction in viable count than antibiotic alone was observed for two strains
Conclusion: This study showed that although TBO-PDI did not have good bactericidal activity against S. aureus biofilms; it increased the antimicrobial activity of linezolid against these bacteria
Subject(s)
Photosensitizing Agents/therapeutic use , In Vitro Techniques , Anti-Infective Agents/chemistry , Staphylococcus aureus , Linezolid , Combined Modality TherapyABSTRACT
Abstract An actinobacterial strain VL-RK_09 having potential antimicrobial activities was isolated from a mango orchard in Krishna District, Andhra Pradesh (India) and was identified as Arthrobacter kerguelensis. The strain A. kerguelensis VL-RK_09 exhibited a broad spectrum of in vitro antimicrobial activity against bacteria and fungi. Production of bioactive metabolites by the strain was the highest in modified yeast extract malt extract dextrose broth, as compared to other media tested. Lactose (1%) and peptone (0.5%) were found to be the most suitable carbon and nitrogen sources, respectively, for the optimum production of the bioactive metabolites. The maximum production of the bioactive metabolites was detected in the culture medium with an initial pH of 7, in which the strain was incubated for five days at 30 °C under shaking conditions. Screening of secondary metabolites obtained from the culture broth led to the isolation of a compound active against a wide variety of Gram-positive and negative bacteria and fungi. The structure of the first active fraction was elucidated using Fourier transform infrared spectroscopy, electrospray ionization mass spectrometry, 1H and 13C nuclear magnetic resonance spectroscopy. The compound was identified as S,S-dipropyl carbonodithioate. This study is the first report of the occurrence of this compound in the genus Arthrobacter.
Subject(s)
Arthrobacter/isolation & purification , Arthrobacter/metabolism , Mangifera/microbiology , Anti-Infective Agents/metabolism , Anti-Infective Agents/pharmacology , Salts/metabolism , Temperature , Carbon/metabolism , Microbial Sensitivity Tests , Metabolome , Metabolomics/methods , Hydrogen-Ion Concentration , Anti-Infective Agents/isolation & purification , Anti-Infective Agents/chemistry , Minerals/metabolism , Nitrogen/metabolismABSTRACT
BACKGROUND: The development of new drugs or alternative therapies effective against methicillin-resistant Staphylococcus aureus (MRSA) is of great importance, and various natural anti-MRSA products are good candidates for combination therapies. We evaluated the antibacterial activities of a Phellinus baumii ethyl acetate extract (PBEAE) and its synergistic effects with beta-lactams against MRSA. METHODS: The broth microdilution method was used to determine the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of the PBEAE. The PBEAE synergistic effects were determined by evaluating the MICs of anti-staphylococcal antibiotic mixtures, with or without PBEAE. Anti-MRSA synergistic bactericidal effects of the PBEAE and beta-lactams were assessed by time-killing assay. An ELISA was used to determine the effect of the PBEAE on penicillin binding protein (PBP)2a production. RESULTS: The MICs and MBCs of PBEAE against MRSA were 256-512 and 1,024-2,048 microg/mL, respectively. The PBEAE significantly reduced MICs of all beta-lactams tested, including oxacillin, cefazolin, cefepime, and penicillin. However, the PBEAE had little or no effect on the activity of non-beta-lactams. Time-killing assays showed that the synergistic effects of two beta-lactams (oxacillin and cefazolin) with the PBEAE were bactericidal in nature (Deltalog10 colony forming unit/mL at 24 hr: 2.34-2.87 and 2.10-3.04, respectively). The PBEAE induced a dose-dependent decrease in PBP2a production by MRSA, suggesting that the inhibition of PBP2a production was a major synergistic mechanism between the beta-lactams and the PBEAE. CONCLUSIONS: PBEAE can enhance the efficacy of beta-lactams for combined therapy in patients infected with MRSA.
Subject(s)
Acetates/chemistry , Agaricales/chemistry , Anti-Infective Agents/chemistry , Drug Synergism , Enzyme-Linked Immunosorbent Assay , Methicillin-Resistant Staphylococcus aureus/drug effects , Microbial Sensitivity Tests , Penicillin-Binding Proteins/analysis , Plant Extracts/chemistry , beta-Lactams/pharmacologyABSTRACT
The aim of this study was to evaluate the subcutaneous tissue response in rats and the antimicrobial activity of intracanal calcium hydroxide dressings mixed with different substances against E. faecalis. Fifty four rats were divided into three experimental groups according to the vehicle in the calcium hydroxide treatment: 0.4% chlorohexidine in propylene glycol (PG),Casearia sylvestris Sw in PG and calcium hydroxide+PG (control group). The pastes were placed into polyethylene tubes and implanted into the subcutaneous tissue. After 7, 14 and 30 days, the samples were processed and histologically evaluated (hematoxylin and eosin). The tissue surface in contact with the material was analyzed, and the quantitative analysis determined the volume density occupied by the inflammatory infiltrate (giant cells, polymorphonuclear cells and mononuclear cells), fibroblasts, collagen fibers and blood vessels. For the antimicrobial analysis, 20 dentin blocks infected with E. faecalis were treated with calcium hydroxide pastes in different vehicles; 0.4% chlorhexidine in PG, PG, extract fromCasearia sylvestris Sw in PG and a positive control (infection and without medication) for 7 days. The efficiency of the pastes was evaluated by the live/dead technique and confocal microscopy. The results showed that 0.4% chlorhexidine induced a higher inflammatory response than the other groups. The Casearia sylvestris Sw extract showed satisfactory results in relation to the intensity of the inflammatory response. In the microbiological test, there were no statistical differences between the evaluated intracanal dressings and the percentage of bacterial viability was between 33 and 42%. The control group showed an 86% viability. Antimicrobial components such as chlorhexidine or Casearia sylvestris Sw did not improve the antimicrobial activity against E. faecalis in comparison to the calcium hydroxide+PG treatment. In addition, the incorporation of chlorhexidine in the calcium hydroxide paste promoted the highest inflammatory response.
Subject(s)
Animals , Cattle , Anti-Infective Agents/pharmacology , Calcium Hydroxide/pharmacology , Casearia/chemistry , Chlorhexidine/pharmacology , Subcutaneous Tissue/drug effects , Anti-Infective Agents/chemistry , Calcium Hydroxide/chemistry , Cells, Cultured , Chlorhexidine/chemistry , Collagen/drug effects , Enterococcus faecalis/drug effects , Fibroblasts/drug effects , Materials Testing , Microbial Viability/drug effects , Ointments , Pharmaceutical Vehicles/chemistry , Pharmaceutical Vehicles/pharmacology , Propylene Glycol/chemistry , Propylene Glycol/pharmacology , Rats, Wistar , Subcutaneous Tissue/pathology , Time FactorsABSTRACT
O objetivo deste estudo foi avaliar as propriedades químicas, biológicas e antimicrobianas dos solventes endodônticos, Citrol, Eucaliptol, d-Limoneno, Xilol e Endosolv E. Dentre os testes químicos, foram avaliados a microdureza dentinária, onde utilizamos blocos de dentina bovina que foram expostos aos solventes por 2 períodos, 5 e 15 min e submetidos ao teste de microdureza. Outro teste químico foi a capacidade de dissolução dos materiais obturadores pelo teste de imersão nos solventes em 3 períodos, 2, 5 e 15 min. Para essa avaliação foram, confeccionados corpos de prova dos cimentos, AH Plus, Acroseal, Sealer 26, Endofill, MTA Fillapex e RealSeal SE e dos cones de guta-percha estandardizado Dentsply (DP), ProTaper e Resilon. Um terceiro teste, foi realizado para avaliar a capacidade de desobturação dos canais radiculares e o efeito da agitação ultrassônica dos solventes endodônticos após a desobturação. Sessenta incisivos centrais superiores foram divididos em 6 grupos sendo um para cada solvente (n=10) mais um grupo controle (solução fisiológica). Todos dentes foram instrumentados e obturados pela mesma técnica e escaneados no Micro-CT. Os dentes foram então desobturados utilizando ProTaper Retratamento/ProTaper Universal como técnica para todos grupos, associada a um dos solventes e foram escaneados novamente para a avaliação do volume de material remanescente após a desobturação. Cada um dos dentes foi desobturado e preenchido com o mesmo solvente utilizado na desobturação. Cada solvente foi agitado pelo ultrassom por 1 min e novamente foram escaneados e avaliados os volumes restantes dos materiais nos canais radiculares. Na avaliação biológica, utilizamos o teste de citotoxicidade com células de camundongo NIH-3T3 pelo ensaio MTT. As culturas celulares foram plaqueadas e submetidas aos solventes diluídos nas concentrações de 0.5 a 2.5%, e avaliados quanto à viabilidade celular. Por fim o último teste foi o antimicrobiano, avaliado pelo teste de...
The aim of this study was to evaluate the chemical, biological and antimicrobial properties of the Endodontic solvents, Citrol, Eucalyptol, d-Limonene, Xylene and Endosolv E. First chemical properties analysis were evaluated by dentin microhardness, where we used bovine dentin blocks that were exposed to the solvents in 2 periods, 5 and 15 min and subjected to the microhardness test. Second test was to evaluate the ability of endodontic solvents to dissolve root-filling materials by immersion test in, 2, 5 and 15 minutes. Specimens of sealers, AH Plus, Acroseal, Sealer 26, Endofill, MTA Fillapex an RealSeal SE and guttapercha Dentsply (DP), ProTaper and Resilon points were prepared and evaluated in the three periods. Next test was conducted to evaluate the ability of solvents to desobturate root canals filled and analyse the effect of the ultrasonic passive agitation of solvents after canal unfill procedure. Sixty maxillary central incisors were prepared and obturated by same technique and randomly divided into 6 groups, one for each solvent (n=10) and a control group (saline solution). Teeth were scanned in Microcomputed Tomography (Micro-CT), unfilled with ProTaper Retratament/Protaper Universal with one of the solvents and scanned again. The residual root-fillings volumes were analysed and all teeth root canal were filled with the same solvent used in unfilling process and were passive-ultrasonically agitated (PUl) for 1 min. All teeth were scanned again in Micro-CT and data were analysed. Biological properties assessments were evaluated by cytotoxicity test with NIH-3T3 mouse cells by MTT assay. Cell cultures were subjected to diluted solvents at concentrations of 0.5 to 2.5%, and cell viability were analysed. Last evaluation in our study was the antimicrobial test. A total of 60 bovine dentin specimens infected intraorally were exposed for 5 min in direct contact to one of the solvents evaluated. After that, the dentin blocks with biofilms were...
Subject(s)
Animals , Cattle , Mice , Anti-Infective Agents/chemistry , Dentin , Root Canal Filling Materials/chemistry , Solvents/chemistry , Cyclohexanols/chemistry , Fibroblasts , Hardness Tests , Materials Testing , Monoterpenes/chemistry , Retreatment , Time Factors , Tomography, X-Ray Computed , Root Canal Therapy/methodsABSTRACT
O objetivo deste estudo foi avaliar as propriedades físico-químicas, antimicrobianas e biocompatibilidade do MTA branco manipulado com extratos aquoso e/ou em propilenoglicol da Arctium lappa L., Casearia sylvestris Sw. e própolis. Dentre os testes físico-químicos foram avaliados o tempo de presa, escoamento, pH, liberação de íons cálcio e alteração volumétrica. Para verificar o efeito antimicrobiano foram aplicadas as metodologias do contato direto (Enterococcus faecalis e a Cândida albicans) e da descontaminação dentinária, empregando a microscopia confocal de varredura laser para verificar a viabilidade de Enterococcus faecalis. Para a avaliação da biocompatibilidade, 162 ratos Wistar foram utilizados, onde cada animal recebeu dois implantes subcutâneos e um alveolar. Após os períodos experimentais de 15, 30 e 60 dias foram realizadas análises microtomográfica, histológica descritiva e histomorfométrica. Adicionalmente amostras do tecido alveolar foram processadas para dosagem das citocinas TNF-α e IL-10 por meio do ensaio imunoenzimático (ELISA). Os dados obtidos foram analisados estatisticamente com os testes ANOVA e Tukey ou Kruskal-Wallis e Dunn. Os resultados revelaram que a variação do veículo associado ao MTA aumentou significativamente o tempo de presa, no entanto, não houve influência na alteração volumétrica (P>0,05) e na capacidade do cimento em manter o meio alcalino e liberar íons cálcio. Os cimentos manipulados com extratos em propilenoglicol apresentaram maior escoamento (P<0,05). Apenas o extrato da própolis agregou ao MTA efeito contra o Enterococcus faecalis após 24 e 48 horas (descontaminação dentinária e contato direto respectivamente) e contra a Cândida albicans após 10 horas (P<0,05). De acordo com as avaliações histológica e histomorfométrica dos implantes em tecidos subcutâneo e alveolar não foi constatada diferença significativa entre os grupos experimentais quando comparados com o grupo no qual o MTA foi manipulado...
The aim of this study was to evaluate the physicochemical, antimicrobial properties and biocompatibility of white MTA mixed with aqueous or propylene glycol extracts of Arctium lappa L., Casearia sylvestris Sw. and propolis. Among physicochemical tests were evaluated the setting time, flowability, pH, ion calcium release and volumetric change. To verify the antimicrobial effects were applied the methods of direct contact (Enterococcus faecalis and Candida albicans) and dentin decontamination by using the confocal laser scanning microscopy to verify the Enterococcus faecalis viability. To evaluate the biocompatibility were used 162 Wistar rats. Each animal received one alveolar and two subcutaneous implants. After the experimental periods of 15, 30 and 60 days were performed the microtomography, histological description and histomorphometric analyses. Additionally alveolar tissue samples were processed for the measurement of TNF-α e IL-10 cytokines by enzyme-linked immunosorbent assay (ELISA). The data were statistically analyzed by the ANOVA and Tukey or KruskalWallis and Dunns tests. The results revealed that the variation of the vehicle associated to MTA significantly increased its setting time, however did not influence the volumetric change (P>0,05) and the cement's ability to maintain the alkaline medium and ion calcium release. Cements mixed with propylene glycol extracts showed higher flowability (P<0,05). Only propolis extract added to MTA the effect against E. faecalis after 24 and 48 hours (dentin decontamination and direct contact respectively) and against Candida albicans after 10 hours (P<0,05). According to the histological and histomorphometric evaluation of the implants in subcutaneous and alveolar tissue was not observed significant differences between the experimental groups in comparison to the reference group (MTA was mixed with distilled water). The microtomography analysis and expression of TNF-α and IL-10 showed...
Subject(s)
Animals , Male , Rats , Anti-Infective Agents/chemistry , Aluminum Compounds/chemistry , Calcium Compounds/chemistry , Oxides/chemistry , Phytotherapeutic Drugs , Propolis/chemistry , Silicates/chemistry , Anti-Infective Agents/therapeutic use , Biocompatible Materials , Candida albicans , Aluminum Compounds/therapeutic use , Calcium Compounds/therapeutic use , Drug Combinations , Enterococcus faecalis , Materials Testing , Oxides/therapeutic use , Propolis/therapeutic use , Rats, Wistar , Reproducibility of Results , Silicates/therapeutic use , Time FactorsABSTRACT
O objetivo deste estudo foi avaliar as propriedades químicas, biológicas e antimicrobianas dos solventes endodônticos, Citrol, Eucaliptol, d-Limoneno, Xilol e Endosolv E. Dentre os testes químicos, foram avaliados a microdureza dentinária, onde utilizamos blocos de dentina bovina que foram expostos aos solventes por 2 períodos, 5 e 15 min e submetidos ao teste de microdureza. Outro teste químico foi a capacidade de dissolução dos materiais obturadores pelo teste de imersão nos solventes em 3 períodos, 2, 5 e 15 min. Para essa avaliação foram, confeccionados corpos de prova dos cimentos, AH Plus, Acroseal, Sealer 26, Endofill, MTA Fillapex e RealSeal SE e dos cones de guta-percha estandardizado Dentsply (DP), ProTaper e Resilon. Um terceiro teste, foi realizado para avaliar a capacidade de desobturação dos canais radiculares e o efeito da agitação ultrassônica dos solventes endodônticos após a desobturação. Sessenta incisivos centrais superiores foram divididos em 6 grupos sendo um para cada solvente (n=10) mais um grupo controle (solução fisiológica). Todos dentes foram instrumentados e obturados pela mesma técnica e escaneados no Micro-CT. Os dentes foram então desobturados utilizando ProTaper Retratamento/ProTaper Universal como técnica para todos grupos, associada a um dos solventes e foram escaneados novamente para a avaliação do volume de material remanescente após a desobturação. Cada um dos dentes foi desobturado e preenchido com o mesmo solvente utilizado na desobturação. Cada solvente foi agitado pelo ultrassom por 1 min e novamente foram escaneados e avaliados os volumes restantes dos materiais nos canais radiculares. Na avaliação biológica, utilizamos o teste de citotoxicidade com células de camundongo NIH-3T3 pelo ensaio MTT. As culturas celulares foram plaqueadas e submetidas aos solventes diluídos nas concentrações de 0.5 a 2.5%, e avaliados quanto à viabilidade celular. Por fim o último teste foi o antimicrobiano, avaliado pelo teste de...
The aim of this study was to evaluate the chemical, biological and antimicrobial properties of the Endodontic solvents, Citrol, Eucalyptol, d-Limonene, Xylene and Endosolv E. First chemical properties analysis were evaluated by dentin microhardness, where we used bovine dentin blocks that were exposed to the solvents in 2 periods, 5 and 15 min and subjected to the microhardness test. Second test was to evaluate the ability of endodontic solvents to dissolve root-filling materials by immersion test in, 2, 5 and 15 minutes. Specimens of sealers, AH Plus, Acroseal, Sealer 26, Endofill, MTA Fillapex an RealSeal SE and guttapercha Dentsply (DP), ProTaper and Resilon points were prepared and evaluated in the three periods. Next test was conducted to evaluate the ability of solvents to desobturate root canals filled and analyse the effect of the ultrasonic passive agitation of solvents after canal unfill procedure. Sixty maxillary central incisors were prepared and obturated by same technique and randomly divided into 6 groups, one for each solvent (n=10) and a control group (saline solution). Teeth were scanned in Microcomputed Tomography (Micro-CT), unfilled with ProTaper Retratament/Protaper Universal with one of the solvents and scanned again. The residual root-fillings volumes were analysed and all teeth root canal were filled with the same solvent used in unfilling process and were passive-ultrasonically agitated (PUl) for 1 min. All teeth were scanned again in Micro-CT and data were analysed. Biological properties assessments were evaluated by cytotoxicity test with NIH-3T3 mouse cells by MTT assay. Cell cultures were subjected to diluted solvents at concentrations of 0.5 to 2.5%, and cell viability were analysed. Last evaluation in our study was the antimicrobial test. A total of 60 bovine dentin specimens infected intraorally were exposed for 5 min in direct contact to one of the solvents evaluated. After that, the dentin blocks with biofilms were...
Subject(s)
Animals , Cattle , Mice , Anti-Infective Agents/chemistry , Dentin , Root Canal Filling Materials/chemistry , Solvents/chemistry , Cyclohexanols/chemistry , Fibroblasts , Hardness Tests , Materials Testing , Monoterpenes/chemistry , Retreatment , Time Factors , Tomography, X-Ray Computed , Root Canal Therapy/methodsABSTRACT
O objetivo deste estudo foi avaliar as propriedades físico-químicas, antimicrobianas e biocompatibilidade do MTA branco manipulado com extratos aquoso e/ou em propilenoglicol da Arctium lappa L., Casearia sylvestris Sw. e própolis. Dentre os testes físico-químicos foram avaliados o tempo de presa, escoamento, pH, liberação de íons cálcio e alteração volumétrica. Para verificar o efeito antimicrobiano foram aplicadas as metodologias do contato direto (Enterococcus faecalis e a Cândida albicans) e da descontaminação dentinária, empregando a microscopia confocal de varredura laser para verificar a viabilidade de Enterococcus faecalis. Para a avaliação da biocompatibilidade, 162 ratos Wistar foram utilizados, onde cada animal recebeu dois implantes subcutâneos e um alveolar. Após os períodos experimentais de 15, 30 e 60 dias foram realizadas análises microtomográfica, histológica descritiva e histomorfométrica. Adicionalmente amostras do tecido alveolar foram processadas para dosagem das citocinas TNF-α e IL-10 por meio do ensaio imunoenzimático (ELISA). Os dados obtidos foram analisados estatisticamente com os testes ANOVA e Tukey ou Kruskal-Wallis e Dunn. Os resultados revelaram que a variação do veículo associado ao MTA aumentou significativamente o tempo de presa, no entanto, não houve influência na alteração volumétrica (P>0,05) e na capacidade do cimento em manter o meio alcalino e liberar íons cálcio. Os cimentos manipulados com extratos em propilenoglicol apresentaram maior escoamento (P<0,05). Apenas o extrato da própolis agregou ao MTA efeito contra o Enterococcus faecalis após 24 e 48 horas (descontaminação dentinária e contato direto respectivamente) e contra a Cândida albicans após 10 horas (P<0,05). De acordo com as avaliações histológica e histomorfométrica dos implantes em tecidos subcutâneo e alveolar não foi constatada diferença significativa entre os grupos experimentais quando comparados com o grupo no qual o MTA foi manipulado...
The aim of this study was to evaluate the physicochemical, antimicrobial properties and biocompatibility of white MTA mixed with aqueous or propylene glycol extracts of Arctium lappa L., Casearia sylvestris Sw. and propolis. Among physicochemical tests were evaluated the setting time, flowability, pH, ion calcium release and volumetric change. To verify the antimicrobial effects were applied the methods of direct contact (Enterococcus faecalis and Candida albicans) and dentin decontamination by using the confocal laser scanning microscopy to verify the Enterococcus faecalis viability. To evaluate the biocompatibility were used 162 Wistar rats. Each animal received one alveolar and two subcutaneous implants. After the experimental periods of 15, 30 and 60 days were performed the microtomography, histological description and histomorphometric analyses. Additionally alveolar tissue samples were processed for the measurement of TNF-α e IL-10 cytokines by enzyme-linked immunosorbent assay (ELISA). The data were statistically analyzed by the ANOVA and Tukey or KruskalWallis and Dunns tests. The results revealed that the variation of the vehicle associated to MTA significantly increased its setting time, however did not influence the volumetric change (P>0,05) and the cement's ability to maintain the alkaline medium and ion calcium release. Cements mixed with propylene glycol extracts showed higher flowability (P<0,05). Only propolis extract added to MTA the effect against E. faecalis after 24 and 48 hours (dentin decontamination and direct contact respectively) and against Candida albicans after 10 hours (P<0,05). According to the histological and histomorphometric evaluation of the implants in subcutaneous and alveolar tissue was not observed significant differences between the experimental groups in comparison to the reference group (MTA was mixed with distilled water). The microtomography analysis and expression of TNF-α and IL-10 showed...
Subject(s)
Animals , Male , Rats , Anti-Infective Agents/chemistry , Aluminum Compounds/chemistry , Calcium Compounds/chemistry , Oxides/chemistry , Phytotherapeutic Drugs , Propolis/chemistry , Silicates/chemistry , Anti-Infective Agents/therapeutic use , Biocompatible Materials , Candida albicans , Aluminum Compounds/therapeutic use , Calcium Compounds/therapeutic use , Drug Combinations , Enterococcus faecalis , Materials Testing , Oxides/therapeutic use , Propolis/therapeutic use , Rats, Wistar , Reproducibility of Results , Silicates/therapeutic use , Time FactorsABSTRACT
The adhesion of biofilm on dental prostheses is a prerequisite for the occurrence of oral diseases. Objective: To assess the antimicrobial activity and the mechanical properties of an acrylic resin embedded with nanostructured silver vanadate (β-AgVO3). Material and Methods: The minimum inhibitory concentration (MIC) of β-AgVO3 was studied in relation to the species Staphylococcus aureus ATCC 25923, Streptococcus mutans ATCC 25175, Pseudomonas aeruginosa ATCC 27853, and Candida albicans ATCC 10231. The halo zone of inhibition method was performed in triplicate to determine the inhibitory effect of the modified self-curing acrylic resin Dencor Lay - Clássico®. The surface hardness and compressive strength were examined. The specimens were prepared according to the percentage of β-AgVO3 (0%-control, 0.5%, 1%, 2.5%, 5%, and 10%), with a sample size of 9x2 mm for surface hardness and antimicrobial activity tests, and 8x4 mm for the compression test. The values of the microbiologic analysis were compared and evaluated using the Kruskal-Wallis test (α=0.05); the mechanical analysis used the Shapiro-Wilk's tests, Levene's test, ANOVA (one-way), and Tukey's test (α=0.05). Results: The addition of 10% β-AgVO3 promoted antimicrobial activity against all strains. The antimicrobial effect was observed at a minimum concentration of 1% for P. aeruginosa, 2.5% for S. aureus, 5% for C. albicans, and 10% for S. mutans. Surface hardness and compressive strength increased significantly with the addition of 0.5% β-AgVO3 (p<0.05). Higher rates of the nanomaterial did not alter the mechanical properties of the resin in comparison with the control group (p>0.05). Conclusions: The incorporation of β-AgVO3 has the potential to promote antimicrobial activity in the acrylic resin. At reduced rates, it improves the mechanical properties, and, at higher rates, it does not promote changes in the control. .
Subject(s)
Acrylic Resins/pharmacology , Anti-Infective Agents/pharmacology , Silver/pharmacology , Vanadates/pharmacology , Acrylic Resins/chemistry , Analysis of Variance , Anti-Infective Agents/chemistry , Candida albicans/drug effects , Candida albicans/growth & development , Compressive Strength , Dental Prosthesis/microbiology , Hardness Tests , Materials Testing , Microbial Sensitivity Tests , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/growth & development , Reproducibility of Results , Silver/chemistry , Staphylococcus aureus/drug effects , Staphylococcus aureus/growth & development , Statistics, Nonparametric , Streptococcus mutans/drug effects , Streptococcus mutans/growth & development , Surface Properties , Time Factors , Vanadates/chemistryABSTRACT
Plectranthus is a large and widespread genus with a diversity of ethnobotanical uses. In traditional medicine P. mollis has been used against snakebites, respiratory stimulant and vasoconstrictor, cardiac depressant, cure for haemorrahage, treatment of mental retardation and rheumatism. P. mollis is reported to exhibit relaxant activity on smooth and skeletal muscles, and has cytotoxic and anti-tumour promoting activity, and can be used in the treatment of cancer. The aim of the present study was to identify chemical composition of the essential oil of P. mollis and to evaluate antimicrobial efficacy of the oil. The essential oil of the flowering aerial parts of P. mollis as obtained by hydro-distillation and analyzed by gas chromatography equipped with a flame ionization detector (GC-FID) and gas chromatography coupled with mass spectrometry (GC/MS). Twentyseven compounds were identified, which comprised 98.6% of the total constituents. The main compound was identified as fenchone (32.3%), followed by α-humulene (17.3%), piperitenone oxide (8.5%), cis-piperitone oxide (6.0%) and E-β-farnesene (5.9%). The oil was found rich in oxygenated monoterpenes type constituents (52.0%), followed by sesquiterpene hydrocarbons (40.2%), oxygenated sesquiterpenes (4.9%), and monoterpene hydrocarbons (1.5%). Antimicrobial activity of the essential oil of P. mollis was tested against six Gram-positive and eight Gram negative bacteria, and three fungi, by using the tube dilution method. The oil was active against the tested Gram-positive and Gram-negative bacteria, and fungi at a concentration range of 0.065±0.008-0.937±0.139mg/mL, 0.468±0.069-3.333±0.527 mg/mL and 0.117±0.0170.338±0.062mg/mL respectively. The present study revealed that the oil constituents somehow were qualitatively similar and quantitatively different than earlier reports from different parts of the world. The essential oil of P. mollis has found to be antimicrobial activity which can be usefulness in the treatment of various infectious diseases caused by bacteria and fungi.
Plectranthus es un género grande y extenso con una diversidad de usos etnobotánicos. En la medicina tradicional P.mollis se ha utilizado contra las mordeduras de serpiente, como estimulante respiratorio y vasoconstrictor, depresor cardiaco, cura para hemorragias, tratamiento del retraso mental y el reumatismo. Se informó que P. mollis presenta actividad relajante sobre los músculos lisos y esqueléticos, y tiene actividad promotora citotóxica y anti - tumoral, además puede ser utilizado en el tratamiento del cáncer. El objetivo del presente estudio fue identificar la composición química del aceite esencial de P. mollis para evaluar la eficacia antimicrobiana del aceite. El aceite esencial de las partes aéreas de las flores de P. mollis se obtuvo por hidro - destilación y se analizó por cromatografía de gases equipado con un detector de ionización de llama (GC-FID), y cromatografía de gases acoplada a espectrometría de masas (GC/MS). Se identificaron veintisiete compuestos, que comprenden el 98.6% de los constituyentes totales. El compuesto principal se identificó como fencona (32.3%), seguido de α-humuleno (17.3%), óxido de piperitenona (8.5 %), óxido de cis piperitona (6.0 %) y E-β-farneseno (5.9%). Se encontró que el aceite es rico en monoterpenos oxigenados de tipo constituyentes (52.0%), seguido de hidrocarburos de sesquiterpeno (40.2%), sesquiterpenos oxigenados (4.9%), e hidrocarburos monoterpenos (1.5 %). La actividad antimicrobiana del aceite esencial de P.mollis se ensayó frente a seis bacterias Gram-negativas y ocho Gram-positivas, y tres hongos, utilizando el método de dilución en tubo. El aceite fue activo contra las bacterias Gram-positivas y Gram-negativas y hongos ensayados, en un intervalo de concentración de 0.065±0.008 a 0.937±0.139mg/ml, 0.468±0.069 a 3.333±0.527mg/ml y 0.117±0.017 a 0.338±0.062mg/ml, respectivamente. El presente estudio reveló que los constituyentes del aceite de alguna manera fueron cualitativamente similares y cuantitativamente diferentes de los informes anteriores de diferentes partes del mundo. Se encontró que la actividad antimicrobiana del aceite esencial de P. mollis puede ser de utilidad en el tratamiento de diversas enfermedades infecciosas causadas por bacterias y hongos.