Modulação in vitro da atividade antibiótica pelo óleo essencial dos frutos de Piper tuberculatum Jacq / Modulación in vitro de la actividad antibiótica por el aceite esencial de frutos de Piper tuberculatum Jacq / In vitro modulation of the antibiotic activity of essential oil from fruits of Piper tuberculatum Jacq

Introdução: Piper tuberculatum Jacq., popularmente conhecida como pimenta-longaou pimenta-d'Arda, é utilizada empiricamente no tratamento de doenças respiratórias (asma, bronquite e tosse) e digestivas (dores abdominais e diarreias). Na literatura é descrita com importantes atividades anti-inflamatória, antimicrobiana, antileucêmico e anti-helmíntica. Objetivos: avaliar a atividade moduladora do óleo essencial dos frutos de P. tuberculatum (OEPT) em associação com diferentes antibióticos frente à Staphylococcus aureus, Escherichia coli e Pseudomona aeruginosa. Metodos: Os frutos (frescos) de P. tuberculatum foram coletados em Barbalha/CE e submetidos à hidrodestilação em aparelho tipo Clevenger para ser extraído o óleo essencial, após a extração o óleo essencial foi tratado com sulfato de sódio anidro para eliminação da umidade residual. A avaliação da atividade antibacteriana e modulação (em resistência bacteriana) frente às cepas de S. aureus (SA358), E. coli (EC27) e P. aeruginosa (PA03) foram determinadas pelo método de microdiluição para identificar a concentração inibitória mínima (CIM), realizada em triplicata. CIM de ≤ 256 µg/mL foi considerado clinicamente relevante. Resultados: a atividade antibacteriana do OEPT exibiu um CIM de ≥ 1024 µg/mL contra as cepas de bactérias de padrão resistente a múltiplas drogas. Na avaliação da atividade moduladora, o OEPT antagonizou o efeito da amicacina contra E. coli e S. aureus, mas teve efeito sinérgico contra P. aeruginosa. Combinado com a getamicina o óleo exibiu antagonismo frente a E. coli, no entanto não apresentou resultado relevante contra S. aureas e P. aeruginosa. A associação do OEPT com o antibiótico imipenem resultou efeito mais relevante, apresentando sinergismo para todas as bactérias avaliadas, por outro lado, em associação com ciprofloxacino não apresentou efeito significante em relação ao controle. Conclusão: O OEPT apresentou uma melhor atividade quando associado ao imipenem frente todas as bactérias avaliadas, mostrando ser uma possível alternativa no desenvolvimento de novos fármacos com atividade antibacteriana advindos de produtos fitoterápicos(AU)

Introducción: Piper tuberculatum Jacq. popularmente conocida como pimenta-longa o pimenta-d'Arda, se utiliza empíricamente en el tratamiento de enfermedades respiratorias (asma, bronquitis y tos) y digestivas (dolor abdominal y diarrea). En la literatura es describe con importantes actividades antiinflamatorias, antimicrobianas, antileucémicas y antihelmínticas. Objetivo: evaluar la actividad moduladora de los aceites esenciales de frutos de P. tuberculatum (AEPT) en asociación con diferentes antibióticos contra Staphylococcus aureus, Escherichia coli y Pseudomona aeruginosa. Metodología: los frutos (frescos) de P. tuberculatum fueron recolectados en Barbalha/CE y sometidos a hidrodestilación en un equipo Clevenger, para extraer el aceite essencial (AEPT), el cual, una vez extraído, fue tratado con sulfato de sodio anhidro para eliminar la humedad residual. Se evaluó su actividad antibacteriana contra las cepas de S. aureus (SA358), E. coli (EC27) y P. aeruginosas (PA03). Empleando el método de microdilución se determinó la concentración inhibitoria mínima (CIM), con tres réplicas por cada tratamiento. Un valor de CIM ≤ 256 µg/mL se considera clínicamente relevante. Resultados: la actividad antibacteriana del AEPT exhibió una CIM ≥ 1024 µg/mL contra las cepas estándar de bacterias resistentes a múltiples fármacos. En efecto, la actividad AEPT antagoniza el efecto de amikacina contra E. coli y S. aureus, pero tenía un efecto sinérgico contra P. aeruginosa. Combinado con la getamicina el aceite exhibió antagonismo contra E. coli, sin embargo no presentó resultado relevante ante S. aureus y P. aeruginosa. La asociación de AEPT con el antibiótico imipenem resultó el efecto más relevante, mostrando sinergismo frente a todas las bacterias evaluadas. Por el contrario, en asociación con ciprofloxacina no mostró ningún efecto significativo con respecto al control. Conclusión: el AEPT presentó una mejor actividad cuando se asoció a imipenem, frente todas las bacterias evaluadas, demostrando ser una posible alternativa en el desarrollo de nuevos fármacos con actividad antimicrobiana, a partir de productos herbarios(AU)

Introduction: Piper tuberculatum Jacq., commonly known as pimenta-longa or pimenta-d'Arda, is empirically used to treat respiratory conditions (asthma, bronchitis and coughing) and digestive disorders (abdominal pain and diarrhea). Reference may be found in the literature to outstanding antiinflammatory, antimicrobial, antileukemic and antihelmintic activity. Objective: Evaluate the modulatory activity of essential oils from fruits of P. tuberculatum (AEPT) combined with various antibiotics againstStaphylococcus aureus, Escherichia coli and Pseudomona aeruginosa. Methods: Fresh fruits of P. tuberculatum were collected in Barbalha, CE, and subjected to hydrodistillation in a Clevenger set to extract the essential oil (AEPT). The oil extracted was then treated with anhydrous sodium sulfate to eliminate residual humidity. Antibacterial activity was evaluated against strains of S. aureus (SA358), E. coli (EC27) and P. aeruginosas (PA03). Minimum inhibitory concentration (MIC) was determined by the microdilution method, with three replications for each treatment. A MIC ≤ 256 µg/mL was considered to be clinically relevant. Results: Antibacterial activity of AEPT displayed a MIC of ≥1024 µg/mL against standard strains of multi-drug resistant bacteria. In fact, activity of AEPT antagonized the effect of amikacin against E. coli and S. aureus, but had a synergic effect against P. aeruginosa. Combined with gentamicin, the oil exhibited antagonism against E. coli, but no relevant result was obtained against S. aureus and P. aeruginosa. Combination of AEPT with the antibiotic imipenem had the most relevant effect, displaying synergism against all the bacteria evaluated. However, in combination with ciprofloxacin it did not show any significant effect with respect to the control. Conclusion: AEPT displayed better activity against all the bacteria evaluated when combined with imipenem, proving to be a possible alternative for the development of new herbal drugs with antimicrobial activity(AU)

Effect of meadowsweet flower extract-pullulan coatings on rhizopus rot development and postharvest quality of cold-stored red peppers.

The study involved an examination of the antifungal activity on red peppers of pullulan coating (P) and pullulan coating containing either water-ethanol (P + eEMF) or ethanol extract of meadowsweet flowers (P + eEMF). Pullulan was obtained from a culture of Aureobasidium pullulans B-1 mutant. Both non-inoculated peppers and those artificially inoculated with Rhizopus arrhizus were coated and incubated at 24 °C for 5 days. The intensity of the decay caused by Rhizopus arrhizus in the peppers with P and P + eEMF coatings was nearly 3-fold lower, and in the case of P + weEMF 5-fold lower, than that observed in the control peppers. Additionally, the P + weEMF coating decreased, almost two-fold the severity of pepper decay compared to other samples. The influence of coating of pepper postharvest quality was examined after 30 days of storage at 6 °C and 70%-75% RH. All coatings formed a thin and well-attached additional layer of an intensified gloss. During storage, color, total soluble solid content and weight loss of coated peppers were subject to lower changes in comparison with uncoated ones. The results indicate the possibility of the application of pullulan coatings containing MFEs as an alternative to the chemical fungicides used to combat pepper postharvest diseases.

Two different effects of calcium on aquaporins in salinity-stressed pepper plants.

Two different effects of calcium were studied, respectively, in plasma membrane vesicles and in protoplasts isolated from roots of control pepper plants (Capsicum annuum L cv. California) or of plants treated with 50 mM NaCl, 10 mM CaCl(2) or 10 mM CaCl(2) + 50 mM NaCl. Under saline conditions, osmotic water permeability (P ( f )) values decreased in protoplasts and plasma membrane vesicles, and the same reduction was observed in the PIP1 aquaporin abundance, indicating inhibitory effects of NaCl on aquaporin functionality and protein abundance. The cytosolic Ca(2+) concentration, [Ca(2+)](cyt), was reduced by salinity, as observed by confocal microscope analysis. Two different actions of Ca(2+) were observed. On the one hand, increase in free cytosolic calcium concentrations associated with stress perception may lead to aquaporin closure. On the other hand, when critical requirements of Ca(2+) were reduced (by salinity), and extra-calcium would lead to an upregulation of aquaporins, indicating that a positive role of calcium at whole plant level combined with an inhibitory mechanism at aquaporin level may work in the regulation of pepper root water transport under salt stress. However, a link between these observations and other cell signalling in relation to water channel gating remains to be established.