Assessment and antimricrobial modulating activity of the extract of Baccharis cinerea DC. from cariri cearense / Avaliação da atividade antimricrobiana e moduladora do extrato de Baccharis cinerea DC. oriunda do cariri cearense

Baccharis cinerea belongs to the Asteraceae family,in Brazil is found in the Northeast and Southeast, occurring in the Caatinga and Mata Atlântica biomes, on the edges of the seasonal forests, board and altitude forests in both regenerating primary and secondary areas. Has proven antimicrobial and antiviral activity and is widely used in folk medicine for its various therapeutic effects and is used as an antiseptic for skin and wound infections, inflammation, diarrhea as well as being used as a purgative.The plants used in the traditional medicine are more and more explored scientifically because they are possible resources of substances with antimicrobial activity in front damage man's health microorganism. In this context the objective of the study was to investigate the antimicrobial activity, modulator activity of antibiotic and in vitro phytochemical prospection of leaf ethanol extracts. Tests were performed on the bacterial strains of Staphylococcus aureus (ATCC 25923), Pseudomonas aeruginosa (ATCC 15442) and Escherichia coli (ATCC 10536). The antibacterial activity was analyzed by means determining the Minimum Inhibitory Concentration (MIC). For the evaluation of the modulating activity, the microdilution method of the diluted extract samples with the antibiotic's amikacin, clindamycin and gentamicin was used. The MIC results were ≥ 1024 µg mL-1 by the bacterial strains. There was a relevance of concentrations in modulation with the antimicrobials tested such as amikacin and gentamicin, there were no discrepancy of clindamycin results in association with the extract. The chemical constituents found were leucoanthocyanidins, flabobenic tannins, flavanones, flavones, flavonoids, xanthones, chalcones, aurones. It is important to note that is necessary to do other studies to evaluate the potential of this species because it has important chemical compounds in reducing antimicrobial resistance.

Baccharis cinerea pertence à família Asteraceae, no Brasil é encontrada nas regiões Nordeste e Sudeste, ocorrendo nos biomas Caatinga e Mata Atlântica, nas bordas das florestas estacionais, tabuleiro e de altitude em áreas primárias e secundárias em regeneração. Tem atividade antimicrobiana e antiviral comprovada e é amplamente utilizado na medicina popular por seus diversos efeitos terapêuticos, sendo utilizado como antisséptico para infecções de pele e feridas, inflamação, diarreia e também como purgante. As plantas utilizadas na medicina tradicional são cada vez mais exploradas cientificamente, pois são possíveis recursos de substâncias com atividade antimicrobiana que prejudicam a saúde do homem. Neste contexto o objetivo do estudo foi investigar a atividade antimicrobiana, atividade moduladora de antibióticos e prospecção fitoquímica in vitro de extratos etanólicos de folhas. Os testes foram realizados nas cepas bacterianas de Staphylococcus aureus (ATCC 25923), Pseudomonas aeruginosa (ATCC 15442) e Escherichia coli (ATCC 10536). A atividade antibacteriana foi analisada por meio da determinação da Concentração Inibitória Mínima (CIM). Para avaliação da atividade moduladora, foi utilizado o método de microdiluição das amostras do extrato diluído com os antibióticos amicacina, clindamicina e gentamicina. Os resultados da MIC foram ≥ 1024 µg mL-1 pelas cepas bacterianas. Houve relevância das concentrações na modulação com os antimicrobianos testados como amicacina e gentamicina, não havendo discrepância nos resultados da clindamicina em associação com o extrato. Os constituintes químicos encontrados foram leucoantocianidinas, taninos flabobênicos, flavanonas, flavonas, flavonóides, xantonas, chalconas, auronas. É importante ressaltar que é necessária a realização de outros estudos para avaliar o potencial desta espécie, pois possui compostos químicos importantes na redução da resistência aos antimicrobianos.

LC-MS analysis and cytoprotective effect against the mercurium and aluminium toxicity by bioactive products of Psidium brownianum Mart. ex DC.

This study aimed to verify the chelating, antioxidant and cytoprotective activities of Psidium brownianum Mart. Ex DC against mercury and aluminum. The ethanolic extract, as well as the tannic and flavonoid fractions, were prepared and subjected to liquid chromatography-mass spectrometry analysis. Ferric ion reduction and antioxidant activity measurement using the FRAP method were performed with P. brownianum. After determining the sub-allelopathic doses, germination tests using Lactuca sativa (lettuce) seeds were performed. The main compounds identified in the extract and fractions were: quercetin and its derivatives; myricetin and its derivatives; gallic acid; ellagic acid; quinic acid and gallocatechin. The Minimum Inhibitory Concentration (MIC) for all samples were ≥ 1024 µg/mL. The flavonoid fraction in association with mercury chloride demonstrated cytoprotection (p < 0.001). The sub-allelopathic concentration used was 64 µg/mL. The extract and fractions were cytoprotective for radicles and caulicles when assayed in association with mercury and against aluminum for radicles. This suggests that the P. brownianum extract and its fractions present cytoprotective activity, possibly related to the antioxidant effect of secondary metabolites, especially flavonoids.

Psidium guajava bioactive product chemical analysis and heavy metal toxicity reduction.

The present study had as its objective to verify the Psidium guajava var. Pomifera L. chelating, antioxidant and cytoprotective effects against mercury and aluminum. The ethanolic extract, tannic and flavonoid fractions were subjected to LC-MS analysis. The Ferric Reducing Antioxidant Power (FRAP) and ferric ion reduction demonstrated a present antioxidant activity. The fungicidal and bactericidal activity of these metals were established. After determining the sub-allelopathic doses, germination tests using Lactuca sativa were performed. Quercetin and its derivatives were the main compounds identified in the extract and the fractions. Mercury chloride significantly reduced the bactericidal effect of the flavonoid fraction (p < 0.001). None of the fractions were cytoprotective against mercury or aluminum in the fungal model assays. Using a sub-allelopathic concentration (64 µg/mL), the ethanolic extract, flavonoid and tannic fractions were found to be cytoprotective against aluminum for radicles, however only the tannic fraction was cytoprotective for caulicles. These data suggest that natural P. guajava products are promising cytoprotective compound sources. This activity may be related to the antioxidant effect of secondary metabolites, mainly flavonoids. Our results point to a potential for environmental intervention product and technique development aimed at mitigating contamination by toxic metals such as mercury and aluminum.

Phytotoxicity reduction of the mercury chloride effect by natural products from Eugenia jambolana Lam.: A new strategy against the toxic metal pollution.

The objective of this work was to evaluate the antioxidant, metal chelating and cytoprotective activity of the Eugenia jambolana Lam. extract, as well as of its flavonoid and tannic fractions, against the action of Mercury Chloride (HgCl2). Flavonoids were quantified and an LC-MS chromatographic analysis was performed to identify secondary metabolites. Fe2+ and Fe3+ chelation tests and antioxidant activity were carried out using the FRAP method. Microbiological tests were performed by microdilution to determine the Minimum Inhibitory Concentration (MIC). From these results the Minimum Bactericidal (MBC) and Minimum Fungicide Concentration (MFC) were evaluated. The allelopathy and cytoprotection assays were performed using eukaryotic and prokaryotic models. The results revealed the presence of phenolic acids and flavonoids in the E. jambolana extract and fractions. The sub-allelopathic concentration (64 µg/mL) was used and the results demonstrated the E. jambolana potential cytoprotective effect against mercury chloride.

Antioxidant and mercury chelating activity of Psidium guajava var. pomifera L. leaves hydroalcoholic extract.

Mercury (Hg) is widely distributed in the environment and is known to produce several adverse effects in organisms. The aim of the present study was to examine the in vitro antioxidant activity and Hg chelating ability of the hydroalcoholic extract of Psidium guajava leaves (HEPG). In addition, the potential protective effects of HEPG against Hg(II) were evaluated using a yeast model (Saccharomyces cerevisiae). HEPG was found to exert significant antioxidant activity in 2,2-diphenyl-1-picrylhydrazyl scavenger and inhibition of lipid peroxidation induced by Fe(II) assays in a concentration-dependent manner. The extract also exhibited significant Hg(II) chelating activity. In yeast, Hg(II) induced a significant decrease in cell viability. In contrast, HEPG partially prevented the fall in cell viability induced by Hg(II). In conclusion, HEPG exhibited protective effects against Hg(II)-mediated toxicity, which may be related to both antioxidant and Hg(II)-chelating activities.

Rhaphiodon echinus (Nees & Mart.) Schauer: Chemical, toxicological activity and increased antibiotic activity of antifungal drug activity and antibacterial.

The association of herbal products with standard antimicrobial drugs has recently gained more attention as a hope to overcome infectious diseases caused by multidrug-resistant microorganisms. Here, we investigated for the first time the antimicrobial (antifungal and antibacterial) activity of ethanolic and aqueous extracts of R. echinus against multiresistant strains of bacteria (E. coli, P. aeruginosa and S. aureus) and fungi (C. albicans, C. krusei and C. tropicalis), as well as potential to enhance the activity of antibiotics drugs. In addition, both extract were chemically characterized and their toxicity was assessed in Artemia salina. Our results demonstrate that aqueous extract of R. echinus caused a significant increase in the activity of antibiotics gentamicin and imipenem, while the ethanolic extract strongly enhanced the antibiotic activity of gentamicin, amikacin, imipenem and ciprofloxacin against P. aeruginosa. However, neither the ethanolic nor the aqueous extracts significantly affect the antibiotic activity of the drugs when tested against S. aureus. Phytochemical analysis of the extracts indicated ellagic acid, caffeic acid and chlorogenic acid as the major components which can be at least in part responsible for the enhanced activity of antibiotics. None of the extracts showed toxicity in A. salina even at the highest concentration tested (1000 µg/mL). All together, our results suggest that the leaf extract of R. echinus can be an effective source of modulating agents.

Efecto citoprotector de extractos de Eugenia jambolana y Psidium myrsinites DC. A. contra peroxidación lipídica inducida por hierro II / Citoprotective effect of Eugenia jambolana and Psidium myrsinites DC. A. against the lipid peroxidation induced by iron II

La evaluación de la actividad antioxidante ha sido una cuestión relevante teniendo en cuenta su importancia para la salud humana. Estudios recientes muestran que el uso de plantas en forma de jugos o tés como fuentes de antioxidantes naturales, que se pueden utilizar como complemento para el tratamiento de diversas enfermedades. En este contexto, evaluado el potencial antioxidante in vitro, de extractos de Eugenia jambolana Lam y Psidium myrsinites DC. A. y cuantificar fenoles y flavonoides presentes en los extractos. La peroxidación lipídica ha sido evaluada por la técnica de TBARS (sustancias reactivas al ácido tiobarbitúrico). De acuerdo con los resultados, mostraron una mejor actividad antioxidante del extracto de psidium myrsinites DC. A. Para poner a prueba TBARS con fosfolípido de huevo extrae redujo los niveles basales en el proceso de peroxidación de lípidos, la CI50 del extracto etanolico de Euguenia jambolana (EEFEJ) mostró los mejores resultados, con un más bajo valor de la CI50 en comparación con el extracto hidroetanolico de Psidium mirsinites, demostrado ser más efectivo. Por lo tanto, a través de estas pruebas se puede ver que los extractos de las hojas de la especie, Eugenia jambolana Lam y Psidium myrsinites DC. A., la actividad antioxidante de exposiciones, sustancias fenólicas directamente relacionados producidos a partir de su metabolismo secundario.

The evaluation of the antioxidant activity has been a relevant and important issue to human health. Recent studies show that the use of plants juices or teas as sources of natural antioxidants, which can be used as an adjuvant in the treatment of several diseases. In this context, was evaluated the in vitro antioxidant potential of the extracts of Psidium myrsinites DC. and Eugenia jambolana Lam. The total of phenols and flavonoids were quantified in the extracts. Lipid peroxidation was evaluated by the technique of TBARS (thiobarbituric acid reactive substances). According to the results, was showed a better antioxidant activity in the extract of Psidium myrsinites DC. A. In the TBARS assay with egg phospholipid the extracts reduced the basal levels in the process of lipid peroxidation and the IC50 of ethanol extract of Eugenia jambolana (EEFEJ) showed the best results with a lower value of IC50 compared with hydroethanol extract of Psidium mirsinites, demonstrating be more effective. Therefore, through these tests can be seen that extracts from the leaves of the species, Eugenia and Psidium jambolana Lam myrsinites DC. A., exhibit antioxidant activity, directly related phenolic substances produced from the secondary metabolism.

Antimicrobial Activity and Modulatory Effect of Essential Oil from the Leaf of Rhaphiodon echinus (Nees & Mart) Schauer on Some Antimicrobial Drugs.

BACKGROUND: Rhaphiodon echinus is a weed plant used in the Brazilian folk medicinal for the treatment of infectious diseases. In this study, the essential oil of R. echinus leaf was investigated for its antimicrobial properties. METHODS: The chemical constituents of the essential oil were characterized by GC-MS. The antimicrobial properties were determined by studying by the microdilution method the effect of the oil alone, and in combination with antifungal or antibiotic drugs against the fungi Candida albicans, Candida krusei and Candida tropicalis and the microbes Escherichia coli, Staphylococcus aureus and Pseudomonas. In addition, the iron (II) chelation potential of the oil was determined. RESULTS: The results showed the presence of ß-caryophyllene and bicyclogermacrene in major compounds, and revealed a low antifungal and antibacterial activity of the essential oil, but a strong modulatory effect on antimicrobial drugs when associated with the oil. The essential oil showed iron (II) chelation activity. CONCLUSIONS: The GC-MS characterization revealed the presence of monoterpenes and sesquiterpenes in the essential oil and metal chelation potential, which may be responsible in part for the modulatory effect of the oil. These findings suggest that essential oil of R. echinus is a natural product capable of enhancing the antibacterial and antifungal activity of antimicrobial drugs.

Psidium guajava L. and Psidium brownianum Mart ex DC.: Chemical composition and anti - Candida effect in association with fluconazole.

The therapeutic combinations have been increasingly used against fungal resistance. Natural products have been evaluated in combination with pharmaceutical drugs in the search for new components able to work together in order to neutralize the multiple resistance mechanisms found in yeasts from the genus Candida. The aqueous and hydroethanolic extracts from Psidium brownianum Mart ex DC. and Psidium guajava L. species were evaluated for their potential to change the effect of commercial pharmaceutical drugs against Candida albicans and Candida tropicalis strains. The tests were performed according to the broth microdilution method. Plate readings were carried out by spectrophotometry, and the data generated the cell viability curve and IC50 of the extracts against the yeasts. A chemical analysis of all the extracts was performed for detection and characterization of the secondary metabolites. The total phenols were quantified in gallic acid eq/g of extract (GAE/g) and the phenolic composition of the extracts was determined by HPLC. Fluconazole and all extracts presented high Minimum Inhibitories Concentrations (MICs). However, when associated with the extracts at sub-inhibitory concentrations (MIC/16), fluconazole had its effect potentiated. A synergistic effect was observed in the combination of fluconazole with Psidium brownianum extracts against all Candida strains. However, for Psidium guajava extracts the synergistic effect was produced mainly against the Candida albicans LM77 and Candida tropicalis INCQS 400042 strains. The IC50 values of fluconazole ranged from 19.22 to 68.1 µg/mL when it was used alone, but from 2.2 to 45.4 µg/mL in the presence of the extracts. The qualitative chemical characterization demonstrated the presence of phenols, flavonoids and tannins among the secondary metabolites. The concentration of total phenols ranged from 49.25 to 80.77 GAE/g in the P. brownianum extracts and from 68.06 to 82.18 GAE/g in the P. guajava extracts. Our results indicated that both P. brownianum and P. guajava extracts are effective on potentiating the effect of fluconazole, and therefore, these plants have the potential for development of new effective drugs for treating fungal infections.

Avaliação da atividade antimicrobiana e moduladora do extrato etanólico de Libidibia ferrea (Mart. ex Tul.) L.P. Queiroz / Evaluación de la actividad antimicrobiana y modulatória del extracto etanólico de Libidibia ferrea (Mart. ex Tul.) L.P. Queiroz / Evaluation of antimicrobial and modulatory activity of the ethanol extract of Libidibia ferrea (Mart. ex Tul.) L.P. Queiroz

Introdução: Staphylococcus aureus é mencionada na literatura como um importante patógeno, algumas espécimes acarretam infecções oportunistas em muitos animais e homens. Escherichia coli é uma das principais causas de doenças infecciosas humanas. Pertencente à família das Enterobacteriaceae, compartilham diversos fatores de virulência descrita por sua resistência a vários antibióticos, as contaminações são provavelmente iniciadas por modificações de defesas do hospedeiro. Pseudomonas aeruginosaé conhecida por causar infecção aguda pela produção de toxinas. Objetivo: avaliar o efeito antimicrobiano do extrato etanólico de Libidibia ferrea (Mart. ex Tul.) L.P. Queiroz, e modulação da atividade antibiótica. Métodos: o material botânico de Libidibia ferrea foi coletado no município de Penaforte, Ceará, Brasil. Para a obtenção dos extratos foram coletadas entrecasca e vagem frescas, submersos em etanol separadamente por 72 h, sendo após esse período, filtrado e concentrado em condensador rotativo a vácuo. Foram realizados testes de atividade antimicrobiana e modulação da atividade antimicrobiana com cepas padrões e multirresistentes de bactérias. Resultados: o extrato demonstrou atividade moduladora quando combinados com alguns antimicrobianos contra algumas linhagens testadas. Conclusões: portanto, é sugerido que o extrato de L. ferrea pode ser utilizada como uma fonte de produtos naturais na terapêutica antimicrobiana e no combate a multirresistência bacteriana(AU)

Introducción: Staphylococcus aureus se menciona en la literatura como un patógeno importante, algunos provocan infecciones oportunistas en animales y hombres. Escherichia coli es una de las principales causas de enfermedades infecciosas humanas. Ambas pertenecen a la familia Enterobacteriaceae, comparten muchos factores de virulencia y se caracterizan por su resistencia a múltiples antibióticos, su contaminación tal vez iniciada por la modificación de las defensas del hospedero. Pseudomonas aeruginosa causa de infección aguda mediante la producción de toxinas. Objetivo: evaluar el efecto antimicrobiano del extracto de etanol de Libidibia ferrea (Mart ex Tul.) LP Queiroz, y la modulación de la actividad antibiótica. Métodos: L. ferrea fue recopilada en el municipio de Penaforte, Ceará, Brasil. Para obtener los extractos se recogieron corteza y frutos frescos, sumergidos en etanol por separado durante 72 h, después se filtraron y se concentraron en un condensador rotatorio. Se realizaron pruebas de actividad antimicrobiana y la modulación de la actividad antimicrobiana con cepas multirresistentes de bacterias. Resultados: los extractos mostraron actividad moduladora cuando se combina con algunos antibióticos contra algunas cepas ensayadas. Conclusión: por lo tanto, se sugiere que el extracto de L. ferrea puede ser utilizado como una fuente de productos naturales en la terapia antimicrobiana y en la resistencia a múltiples fármacos bacteriana combate(AU)

Introduction: Staphylococcus aureus is mentioned in the literature as an important pathogen, some opportunistic bacteria may cause several problems in many animals and humans. Escherichia coli is a leading cause of human infectious diseases. Belonging to the family Enterobacteriaceae, share many virulence factors described by their resistance to multiple antibiotics, the contamination is probably initiated by modifications in the host defenses. Pseudomonas aeruginosa is known to cause acute infection by producing toxins. Objective: evaluate the antimicrobial effect of the ethanol extract of Libidibia ferrea (Mart ex Tul.) LP Queiroz, and modulation of antibiotic activity. Methods: L. ferrea was collected in the municipality of Penaforte, Ceará, Brazil. To obtain the extracts were collected bark and fruits, submerged in ethanol separately for 72 h, after this period, filtered and concentrated in a rotary vacuum condenser. Antimicrobial activity tests were performed and modulation of antimicrobial activity with standards and multiresistant strains of bacteria. Results: the extract showed antibacterial activity when combined with some antibiotics against the assayed strains, demonstrating a modulatory potential. Conclusion: therefore, it is suggested that L. ferrea extract can be used as a source of natural products in the antimicrobial therapy and in the combat bacterial multidrug resistance(AU)

Chemical Characterization and Trypanocidal, Leishmanicidal and Cytotoxicity Potential of Lantana camara L. (Verbenaceae) Essential Oil.

Drug resistance in the treatment of neglected parasitic diseases, such as leishmaniasis and trypanosomiasis, has led to the search and development of alternative drugs from plant origins. In this context, the essential oil extracted by hydro-distillation from Lantana camara leaves was tested against Leishmania braziliensis and Trypanosoma cruzi. The results demonstrated that L. camara essential oil inhibited T. cruzi and L. braziliensis with IC50 of 201.94 µg/mL and 72.31 µg/mL, respectively. L. camara essential oil was found to be toxic to NCTC929 fibroblasts at 500 µg/mL (IC50 = 301.42 µg/mL). The composition of L. camara essential oil analyzed by gas chromatography-mass spectrometry (GC/MS) revealed large amounts of (E)-caryophyllene (23.75%), biciclogermacrene (15.80%), germacrene D (11.73%), terpinolene (6.1%), and sabinene (5.92%), which might be, at least in part, responsible for its activity. Taken together, our results suggest that L. camara essential oil may be an important source of therapeutic agents for the development of alternative drugs against parasitic diseases.

HPLC-DAD phenolic profile, cytotoxic and anti-kinetoplastidae activity of Melissa officinalis.

Context Melissa officinalis subsp. inodora Bornm. (Lamiaceae) has been used since ancient times in folk medicine against various diseases, but it has not been investigated against protozoa. Objective To evaluate the activities of M. officinalis against Leishmania braziliensis, Leishmania infantum and Trypanosoma cruzi as well as its cytotoxicity in fibroblast cell line. Materials and methods The fresh leaves were chopped into 1 cm(2) pieces, washed and macerated with 99.9% of ethanol for 72 h at room temperature. Antiparasitic activity of M. officinalis was accessed by direct counting of cells after serial dilution, while the cytotoxicity of M. officinalis was evaluated in fibroblast cell line (NCTC929) by measuring the reduction of resazurin. The test duration was 24 h. High-performance liquid chromatography (HPLC) was used to characterise the extract. Results The extract at concentrations of 250 and 125 µg/mL inhibited 80.39 and 54.27% of promastigote (LC50 value = 105.78 µg/mL) form of L. infantum, 80.59 and 68.61% of L. brasiliensis (LC50 value = 110.69 µg/mL) and against epimastigote (LC50 value = 245.23 µg/mL) forms of T. cruzi with an inhibition of 54.45 and 22.26%, respectively, was observed. The maximum toxicity was noted at 500 µg/mL with 95.41% (LC50 value = 141.01 µg/mL). The HPLC analysis identified caffeic acid and rutin as the major compounds. Discussion The inhibition of the parasites is considered clinically relevant (< 500 µg/mL). Rutin and caffeic acids may be responsible for the antiprotozoal effect of the extract. Conclusion The ethanol extract of M. officinalis can be considered a potential alternative source of natural products with antileishmania and antitrypanosoma activities.

Phytocompounds and modulatory effects of Anacardium microcarpum (cajui) on antibiotic drugs used in clinical infections.

BACKGROUND: The challenge of antibiotic resistance and the emergence of new infections have generated considerable interest in the exploration of natural products from plant origins as combination therapy. In this context, crude ethanolic extract (CEE), ethyl acetate fraction (EAF), and methanolic fraction (MF) from Anacardium microcarpum were tested alone or in combination with antibiotics (amikacin, gentamicin, ciprofloxacin, and imipenem) against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. METHODS: Antibiotic resistance-modifying activity was performed using the microdilution method by determining the minimal inhibitory concentration (MIC). In addition, phytochemical prospecting analyses of tested samples were carried out. RESULTS: Our results indicated that all the extracts showed low antibacterial activity against multidrug-resistant strains (MIC =512 µg/mL). However, addition of CEE, EAF, and MF to the growth medium at the subinhibitory concentration (MIC/8=64 µg/mL) significantly modulated amikacin- and gentamicin-resistant E. coli 06. CEE and EAF also demonstrated a significant (P<0.001) synergism with imipenem against S. aureus. In contrast, MF antagonized the antibacterial effect of ciprofloxacin and gentamicin against P. aeruginosa 03 and S. aureus 10, respectively. Qualitative phytochemical analysis of the extracts revealed the presence of secondary metabolites including phenols, flavonoids, xanthones, chalcones, and tannin pyrogallates. CONCLUSION: Taken together, our results suggest that A. microcarpum is a natural resource with resistance-modifying antibacterial activity that needs to be further investigated to overcome the present resistant-infection problem.

Avaliação comparativa da modulação de antibióticos, frente às cepas bacterianas de Escherichia coli, Staphylococcus aureus / Evaluación comparativa de la modulación de antibióticos frente a cepas bacterianas de Escherichia Coli, Staphylococcus / Comparative Evaluation of the Modulation of Antibiotic-Activity against Strains of Escherichia coli and Staphylococcus aureus

Introdução: Combinações múltiplas de drogas estão sendo utilizadas no combate à disseminação de bactérias patogênicas resistentes a antibióticos. No entanto, a utilização incorreta desses antibióticos fez com que algumas bactérias sejam selecionadas, deixando apenas as resistentes aos agentes antimicrobianos, com o consequente surgimento de resistência aos antibióticos. Objetivos: Nesse contexto, avaliaram-se as atividades microbiológicas dos antibióticos claritromicina, gentamicina, ciprofloxacino e imipenem, além de comparar as atividades da associação entre esses fármacos, frente às cepas bacterianas de Escherichia coli e Staphylococcus aureus. Materiais e Métodos: A Concentração Inibitória Mínima (CIM) foi realizada pelo método de microdiluição em caldo para cada uma das amostras selecionadas. Posteriormente, com base nos valores das cims, foi avaliado o efeito antimicrobiano da combinação das drogas pelo método de modulação. Resultados: A associação demonstrou efeitos sinérgicos frente às linhagens testadas, sugerindo-se que a associação dos antibióticos testados aumenta o seu potencial antimicrobiano. Conclusão: Nesse sentido, o uso de antibióticos em combinação pode ser realizado mediante investigações posteriores que comprovem a segurança de seu uso.

Introducción: Actualmente, se está utilizando la combinación de múltiples drogas en la lucha contra la propagación de bacterias patógenas resistentes a los antibióticos. Sin embargo, el uso inadecuado de estos antibióticos ha causado que algunas bacterias se seleccionen, con la consiguiente aparición de resistencia a los antibióticos. Objetivo: Se evaluó la actividad microbiológica de los antibióticos claritromicina, gentamicina, ciprofloxacino e imipenem, y se comparó la actividad sinérgica de estos fármacos, frente a las cepas bacterianas de Escherichia coli y Staphylococcus aureus. Materiales y Métodos: Se determinó la Concentración Mínima Inhibitoria (CMI) por el método de microdilución en caldo para cada una de las muestras seleccionadas y se evaluó el efecto antimicrobiano de la combinación de fármacos por el método de modulación. Resultados: La combinación mostró efectos sinérgicos frente a las cepas ensayadas, lo que sugiere que la asociación de los antibióticos ensayados aumenta su potencial antimicrobiano. Conclusión: Se puede utilizar antibióticos en combinación; sin embargo, se requiere realizar investigaciones adicionales que demuestren ser seguros para su utilización.

Introduction: Combining multiple drugs is an strategy used to combat the dissemination of pathogenic and drug resistant bacteria. However, the misuse of these drugs against bacteria have caused the selection of more resistant specimens called multidrug-resistant bacteria. Objective: In this work we evaluated the antibiotic activity of claritromicin, gentamicin, ciprofloxacin and imipenen, alone or associating one by one, against strains of Escherichia coli and Staphylococcus aureus. Material and methods: The minimal inhibitory concentration (mic) was performed using the microdilution assay. Based in the mic values, the antibiotic effect of the drugs alone and in association were determined. Results: The association between the drugs demonstrated the synergism against the bacterial strains. Conclusion: The use of the combined antibiotic-therapy can be positively performed, but additional studies have to be conducted first for proving that its use is safe.

Fumigant activity of the Psidium guajava var. pomifera (Myrtaceae) essential oil in Drosophila melanogaster by means of oxidative stress.

The guava fruit, Psidium guajava var. pomifera (Myrtaceae family), is a native plant from South America. Its leaves and fruits are widely used in popular medicine in tropical and subtropical countries. Drosophila melanogaster has been used as one of the main model organisms in genetic studies since the 1900s. The extensive knowledge about this species makes it one of the most suitable organisms to study many aspects of toxic compound effects. Due to the lack of studies on the effects of the bioactive compounds present in the P. guajava var. pomifera essential oil, we performed a phytochemical characterization by CG-MS and evaluated the toxicity induced by the essential oil in the D. melanogaster insect model. In order to understand the biochemical mechanisms of toxicity, changes on the Nrf2 signaling as well as hallmarks of oxidative stress response were followed in the exposed flies. Our results showed that exposure of insects to the P. guajava oil increased mortality and locomotor deficits in parallel with an oxidative stress response signaling. Therefore, it suggested a bioinsecticidal activity for P. guajava volatile compounds by means of oxidative stress. Further studies are ongoing to identify which oil compounds are responsible for such effect.

Avaliação da atividade citotóxica e potencial antiparasitário in vitro do a-pineno e carvacrol / Cytotoxic and antiparasitic in vitro activities of a-pinene and carvacrol

A leishmaniose e a doença de Chagas tem sido um grande desafio, no que diz respeito à sua terapêutica. Devido à grande dificuldade de encontrar fármacos que garantam uma ação terapêutica eficiente e menos agressora à espécie humana, diferentes produtos naturais vêm sendo testados. Muitas espécies vegetais foram investigadas quanto à sua ação leishmanicida e tripanocida na expectativa de que seus compostos metabólicos possuam atividade antiparasitária e ausência ou baixa citotoxicidade. Neste estudo sobre bioatividade do a-pineno e carvacrol, avaliaram-se os potenciais leishmanicida e tripanocida. O carvacrol apresentou um percentual de inibição de 38,34% e 74,12% para as formas promastigotas e epimastigotas respectivamente, na concentração de 100µg/mL, apresentando uma citotoxicidade de 21,62%. O a-pineno apresentou 100% e 5,30% de inibição para as formas epimastigota e promastigota na concentração de 100 µg/mL, com citotoxicidade de 87,88%.

Leishmaniasis and Chagas Disease represent a great challenge against the modern therapeutics. Due the high difficult to find new drugs with therapeutic efficacy and low toxicity, several natural products had been screened. Many species of plants were investigated about their leishmanicidal and trypanocidal activities. Some phytocompounds are the a-pinene and carvacrol. In this work, we evaluated the bioactivities of a-pinene and carvacrol against Trypanosoma cruzi and Leishmania braziliensis cell lines. The carvacrol inhibited 38,34% and 74,12% of the promatigote and epimastigote forms, respectively at 100 µg/mL, showing a low cytotoxic activity (21,62%). The O a-pinene inhibited 100% and 5,30% against the epimastigote and promastigote forms respectively, at 100 µg/mL, showing a higher cytotoxic activity (87,88%).

Ação protetora de Duguetia furfuracea (A. St.-Hil.) Saff. contra a toxicidade do cloreto de mercúrio em Escherichia coli / Protective action of Duguetia furfuracea (A. St.-Hil.) Saff. against toxicity due to mercury chloride in Escherichia coli / Acción protectora de Duguetia furfuracea (A. St.-Hil.) Saff. contra la toxicidad por cloruro de mercurio en Escherichia coli

Introdução: o mercúrio constitui um dos metais mais tóxicos e sua contaminação tem sido alvo de muitos estudos que buscam desvendar os mecanismos envolvidos em sua toxicidade e seus efeitos deletérios para os seres vivos. A espécie Duguetia furfuracea (A. St.-Hil.) Saff., conhecida popularmente como araticum-bravo, ata-brava e ata de lobo, tem sido utilizada na medicina popular como anti-reumáticas, para o tratamento de disfunções renais, dores na coluna e no estômago, e contra pediculose. Objetivo: avaliar o efeito citoprotetor do extrato etanólico e frações de D. furfuracea frente ao metal pesado cloreto de mercúrio (HgCl 2). Métodos: a caracterização dos metabólitos secundários foi realizada através de prospecção fitoquímica, na qual se observam a alteração de cor ou formação de precipitados após adição de reagentes específicos. A Concentração Inibitória Mínima (CIM) foi determinada pelo método de microdiluição em caldo e a Concentração Bactericida Mínima (CBM) verificada utilizando placas de petri com HIA (Heart Infusion Agar) para transferência das soluções incubadas em placas de microdiluição. Resultados: a prospecção fitoquímica revelou a presença de taninos, flavonoides e alcaloides. Todas as amostras apresentaram um CIM ≥ 1024 µg/mL. De acordo com os resultados obtidos na CBM, o extrato etanólico e as frações de D. furfuracea, exceto a fração hexânica, apresentaram atividade citoprotetora à bactéria E. coli frente ao metal pesado cloreto de mercúrio, sendo essa ação atribuída às propriedades quelantes dos flavonoides. Conclusões: os dados obtidos indicam a espécie D. furfuracea como uma fonte promissora no combate a metais pesados, apresentando-se como protetora de seres procariontes. Este é o primeiro relato do uso de plantas medicinais como agente citoprotetor em modelo bacteriano.

Introduction: mercury is one of the most toxic metals. Contamination by mercury has been the object of many studies aimed at unraveling the mechanisms involved in its toxicity and its harmful effects on living beings. The species Duguetia furfuracea (A. St.-Hil.) Saff., popularly known asaraticum-bravo’, ‘ata-brava’ and ‘ata de lobo’, has been used in folk medicine as antirheumatic and for the treatment of renal dysfunction, spinal pain, stomach ache and pediculosis. Objective: evaluate the cytoprotective effect of the ethanolic extract and fractions of D. furfuracea against the heavy metal mercury chloride (HgCl 2). Methods: characterization of secondary metabolites was performed by phytochemical screening, in which color change and precipitate formation are examined after the addition of specific reagents. Minimum inhibitory concentration (MIC) was determined by broth microdilution, and minimum bactericidal concentration (MBC) was verified using petri plates with HIA (heart infusion agar) to transfer the solutions incubated on microdilution plates. Results: phytochemical screening revealed the presence of tannins, flavonoids an alkaloids. All samples exhibited a MIC ≥ 1024 µg/mL. MBC results showed that the ethanolic extract and all fractions of D. furfuracea except for the hexane fraction have cytoprotective activity by the bacterium E. coli against mercury chloride, an action attributed to the chelating properties of flavonoids. Conclusions: data point to the promising value of the species D. furfuracea against heavy metals, presenting as protectors of procaryote beings. This is the first report on the use of medicinal plants as cytoprotective agents on the bacterial model.

Introducción: el mercurio es uno de los metales más tóxicos y su contaminación ha sido objeto de muchos estudios que tratan de desentrañar los mecanismos implicados en su toxicidad y sus efectos nocivos en los seres vivos. La especie Duguetia furfuracea (A. St.-Hil.) Saff., popularmente conocido como ‘araticum-bravo’, ‘ata-brava’ y ‘ata de lobo’, se ha utilizado en la medicina popular como un anti-reumático para el tratamiento de la disfunción renal, dolor vertebral y de estómago, y contra la pediculosis. Objetivo: evaluar el efecto citoprotector del extracto de etanol y fracciones de D. furfuracea al metal pesado cloruro de mercurio (HgCl2). Métodos: la caracterización de metabolitos secundarios se realizó mediante la prospección fitoquímica, en la que se observa el cambio de color o la formación de precipitados después de la adición de los reactivos específicos. La Concentración Inhibitoria Mínima (CIM) se determinó mediante microdilución en caldo y la Concentración Bactericida Mínima (CBM) verificada usando placas de petri con HIA ( Heart Infusion Agar) para transferencia de las soluciones incubadas en placas de microdilución. Resultados: la prospección fitoquímica reveló la presencia de taninos, flavonoides y alcaloides. Todas las muestras presentaron una CIM ≥ 1024 µg/mL. De acuerdo con los resultados obtenidos en la CBM, el extracto de etanol y fracciones de D. furfuracea, excepto la fracción de hexano, mostraron actividad citoprotectora de la bacteria E. coli delante del cloruro de mercurio, siendo esa acción atribuida a las propiedades quelantes de los flavonoides. Conclusiones: los datos obtenidos indican que la especie D. furfuracea como una fuente prometedora para combatir los metales pesados, que se presentan como protectores de seres procariotas. Este es el primer informe del uso de plantas medicinales como agente citoprotector en el modelo bacteriano.

Avaliação da atividade antioxidante e citoprotetora dos extratos de Eugenia uniflora Lineau e Psidium sobraleanum Proença & landrum contra metais pesados / Evaluación de la actividad citoprotectora y antioxidante de los extractos de Eugenia uniflora Lineau e Psidium sobraleanum Proença & Landrum contra metales pesados / Evaluation of the Cytoprotective and Antioxidant Activity of the Extracts of Eugenia Uniflora Lineau e Psidium Sobraleanum Proença & Landrum Against Heavy Metals

Objetivo: Estudos recentes apontam a utilização de plantas na forma de sucos ou chás como fontes de agentes antioxidantes naturais que apresentam baixo risco podendo ser utilizado no auxílio do tratamento de várias doenças. Materiais e métodos: Neste contexto, avaliaram-se os potenciais antioxidantes, in vitro, dos extratos de Eugenia uniflora e Psidium sobraleanum, além de quantificar fenóis e flavonoides presentes nos extratos. Resultados: De acordo com os resultados obtidos, observou-se uma melhor atividade antioxidante para o extrato de Eugenia uniflora, para o teste de TBARS com fosfolipídio de ovo, os extratos reduziram os níveis basais no processo de peroxidação lipídica, e quando induzidos por Fe2+ o extrato de Psidium sobraleanum mostrouse mais eficiente. Conclusões: Portanto, através destes ensaios pode-se verificar que os extratos das folhas das espécies, Eugenia uniflora e Psidium sobraleanum, apresentam uma atividade antioxidante, diretamente relacionada com substâncias fenólicas produzidas a partir do seu metabolismo secundário.

Objetivo: Estudios recientes reportan la utilización de plantas en forma de zumos o té como fuente de agentes antioxidantes naturales que presentan bajo riesgo, pudiendo ser utilizados como complemento del tratamiento de diversas enfermedades. Materiales y métodos: En este contexto, se evaluarán in vitro, los potenciales antioxidantes, de los extractos de Eugenia uniflora y Psidium sobraleanum, además de cuantificar fenoles y flavonoides presentes en los extractos. Resultados: De acuerdo con los resultados obtenidos, se observó una mejor actividad antioxidante con el extracto de Eugenia uniflora, en el test de TBARS con fofolípidos de huevo, los extractos redujeron los niveles basales en el proceso de peroxidación lipídica; y cuando fue inducida con Fe+2, el extracto de Psidium sobraleanum se mostró más eficiente. Conclusiones: Por lo tanto, a través de estos ensayos se pudo comprobar que los extractos de las hojas de las especies Eugenia uniflora y Psidium sobraleanum presentan actividad antioxidante, directamente relacionada con sustancias fenólicas producidas a partir de sus metabolitos secundarios.

Objective: Evaluation of antioxidant activity has been an important issue considering its importance in human health. Recent studies show that the use of plants in the form of juices or teas as sources of natural antioxidants with low risk can be used as an aid to the treatment of various diseases. Material and Methods: Evaluation of the antioxidant potential in vitro, extracts of Eugenia uniflora and Psidium sobraleanum, as well as the quantification of phenols and flavonoids present in the extracts. Results: Findings showed a better antioxidant activity for the extract of Eugenia uniflora. In the TBARS test with egg phospholipids, extracts presented a reduction in the basal levels in the lipid peroxidation process; and when the Fe2 + extract was inducted, Psidium sobraleanum proved to be more efficient.. Conclusions: These tests proved that the extracts of leaves of the species Eugenia uniflora and Psidium sobraleanum present antioxidant activity which is directly related to phenolic substances produced in its secondary metabolism.

AvaliaþÒo da atividade citotóxica e potencial antiparasitário in vitro do a-pineno e carvacrol / Cytotoxic and antiparasitic in vitro activities of a-pinene and carvacrol

A leishmaniose e a doenþa de Chagas tem sido um grande desafio, no que diz respeito O sua terapÛutica. Devido O grande dificuldade de encontrar fármacos que garantam uma aþÒo terapÛutica eficiente e menos agressora O espécie humana, diferentes produtos naturais vÛm sendo testados. Muitas espécies vegetais foram investigadas quanto O sua aþÒo leishmanicida e tripanocida na expectativa de que seus compostos metabólicos possuam atividade antiparasitária e ausÛncia ou baixa citotoxicidade. Neste estudo sobre bioatividade do a-pineno e carvacrol, avaliaram-se os potenciais leishmanicida e tripanocida. O carvacrol apresentou um percentual de inibiþÒo de 38,34% e 74,12% para as formas promastigotas e epimastigotas respectivamente, na concentraþÒo de 100Ag/mL, apresentando uma citotoxicidade de 21,62%. O a-pineno apresentou 100% e 5,30% de inibiþÒo para as formas epimastigota e promastigota na concentraþÒo de 100 Ag/mL, com citotoxicidade de 87,88%.(AU)

Leishmaniasis and Chagas Disease represent a great challenge against the modern therapeutics. Due the high difficult to find new drugs with therapeutic efficacy and low toxicity, several natural products had been screened. Many species of plants were investigated about their leishmanicidal and trypanocidal activities. Some phytocompounds are the a-pinene and carvacrol. In this work, we evaluated the bioactivities of a-pinene and carvacrol against Trypanosoma cruzi and Leishmania braziliensis cell lines. The carvacrol inhibited 38,34% and 74,12% of the promatigote and epimastigote forms, respectively at 100 Ag/mL, showing a low cytotoxic activity (21,62%). The O a-pinene inhibited 100% and 5,30% against the epimastigote and promastigote forms respectively, at 100 Ag/mL, showing a higher cytotoxic activity (87,88%).(AU)