Inibição do sistema quorum sensing AI-1 por Capsicum frutescens e Capsicum annuum em bactérias Gram-negativas / Inhibition of AI-1 quorum-sensing system by Capsicum frutescens and Capsicum annuum in Gram-negative bacteria

A inibição do quorum sensing (QS) altera a comunicação bacteriana, reduzindo a expressão de fatores de virulência e a formação de biofilmes, o que pode conferir menor pressão seletiva em comparação aos antibióticos tradicionais. As frutas e hortaliças constituem uma fonte rica em compostos com propriedades potenciais de inibição do QS. Entretanto, há pouca referência sobre o potencial de pimentas do gênero Capsicum e de seus compostos isolados como inibidores do QS. Esse trabalho teve como objetivo avaliar o efeito de extratos orgânicos obtidos das variedades de pimenta-malagueta e pimentão vermelho sobre o sistema QS dependente do sinalizador AI-1 (acil homoserina lactona - AHL) em bactérias Gram-negativas. Os extratos foram obtidos por extração em fase sólida e separados em uma fração metanólica e outra amônica; sendo os compostos característicos identificados e quantificados por cromatografia líquida de alta eficiência (CLAE). A atividade antimicrobiana dos extratos foi avaliada pela determinação da concentração inibitória mínima (MIC) e pela curva de crescimento de Chromobacterium violaceum ATCC 12472, Serratia liquefaciens MG1 e Pseudomonas aeruginosa PAO1. O efeito anti-QS dos extratos foi avaliado pelos testes de difusão em ágar e quantificação da produção de violaceína em meio líquido por C. violaceum e sobre a formação de biofilme, avaliado pelo ensaio de cristal violeta e microscopia confocal, em S. liquefaciens e P. aeruginosa nas temperaturas 30 ºC e 37 ºC. Os resultados obtidos pela CLAE indicaram que o extrato metanólico de pimenta-malagueta (EMPM) continha capsaicinoides como a capsaicina e dihidrocapsaicina, luteolina e outros compostos não identificados; já o extrato amônico desta não continha os compostos capsaicinoides. Ambos os extratos de pimentão vermelho continham luteolina e compostos não identificados, mas não apresentaram capsaicinoides. Como o EMPM era representativo dos demais extratos, por conter tanto capsaicinóides quanto luteolina, o foco deste trabalho foi avaliar os efeitos do EMPM sobre fenótipos microbianos nas concentrações 5; 2,5; 1,25 e 0,625 mg/ml, além de utilizar a capsaicina como controle comparativo em concentrações equivalentes às do extrato (25, 50 e 100 µg/ml). Os resultados da atividade antimicrobiana mostraram inibição parcial do crescimento das bactérias nas concentrações sub-MIC (MIC >5 mg/ml) de 5 e 2,5 mg/ml de EMPM. A capsaicina também inibiu parcialmente o crescimento das bactérias a 100 µg/ml, com exceção de S. liquefaciens a 37 ºC, cujo crescimento foi induzido em 50 e 25 µg/ml. A produção de violaceína foi reduzida pelo EMPM a 1,25 e 0,625 mg/ml, sem afetar o crescimento de C. violaceum. Ensaios com C. violaceum CV026, estirpe biosensora capaz de produzir o pigmento na presença de AI-1 exógeno, sugerem que o possível mecanismo de atuação do extrato sobre o sistema QS em C. violaceum 12472 é sobre a síntese do sinalizador, já que não foi observada inibição da produção de violaceína em CV026 pelo extrato. Contrariamente, a capsaicina incrementou a produção do pigmento na estirpe 12472, mas ensaios com a estirpe CV026 indicaram que a capsaicina não atua como sinalizador do QS, uma vez que esta não induziu a produção de violaceína nesta estirpe. Já a formação de biofilme foi incrementada na presença do EMPM, sendo consideravelmente maior em P. aeruginosa a 30 ºC. Igualmente, observou-se indução da formação de biofilme por capsaicina em S. liquefaciens (37 ºC) e P. aeruginosa (30 ºC). Porém, a capsaicina não teve efeito sobre a formação de biofilme de S. liquefaciens quando cultivada a 30 ºC, nem P. aeruginosa a 37 ºC. Os resultados revelam que a produção de violaceína em C. violaceum ATCC 12472 é inibida pelo EMPM, mas não pela capsaicina. Já, o EMPM e a capsaicina, de forma geral, não inibem a formação de biofilme de S. liquefaciens MG1 nem P. aeruginosa PAO1. Outros estudos são necessários para elucidar os mecanismos pelos quais o EMPM e a capsaicina agem sobre os fenótipos avaliados neste trabalho

Quorum sensing inhibition alters bacterial communication by reducing virulence factors expression and biofilm formation, exerting less selective pressure compared to antibiotics. Fruits and vegetables are rich sources of compounds with potential QS-inhibition properties. However, there are few references about the potential of peppers belonging to the genus Capsicum and its isolated compounds as QS inhibitors. This study aimed to assess the effect of organic extracts obtained from Capsicum varieties, pimenta-malagueta (red chili) and pimentão vermelho (red bell pepper), on the AI-1 dependent QS system. The extracts were obtained by solid phase extraction and split into a methanolic and an ammonic fraction. Characteristic compounds were identified and quantified by high performance liquid chromatography (HPLC). The antimicrobial activity of the extracts was assessed by determining the minimal inhibitory concentration (MIC) and the growth curve of Chromobacterium violaceum ATCC 12472, Serratia liquefaciens MG1 and Pseudomonas aeruginosa PAO1. The anti-QS effect of the extracts was evaluated by the agar diffusion assay and the quantification of violacein production was assessed in liquid medium by C. violaceum, as well as in the biofilm formation test determined by the crystal violet assay and confocal microscopy with S. liquefaciens and P. aeruginosa at 30 ºC and 37 ºC. HPLC results showed that the methanolic extract of pimenta-malagueta (EMPM) contained capsaicinoids such as capsaicin and dihidrocapsaicin, luteolin and other unidentified compounds in lower concentrations; while its ammonic extract did not have capsaicinoids. Both pimentão vermelho extracts contained luteolin and other unidentified compounds in low concentrations, but they did not contain capsaicinoids. As EMPM was representative among the extracts because it contained capsaicinoids and luteolin, the focus of this work was to assess the effect of EMPM over microbial phenotypes at concentrations of 5, 2.5, 1.25 and 0.625 mg/ml, using capsaicin as a comparative control at equivalent concentrations to those in EMPM (25, 50 and 100 µg/ml). Antimicrobial activity assays showed a partial inhibition growth of bacteria at sub-MIC concentrations (MIC >5 mg/ml) of EMPM at 5 and 2.5 mg/ml. Similarly, capsaicin partially inhibited bacterial growth at 100 µg/ml, except for S. liquefaciens at 37 ºC in which growth was induced at 50 and 25 µg/ml. Violacein production was reduced by EMPM at 1,25 and 0,625 mg/ml without affecting C. violaceum growth. Assays with C. violaceum CV026, a biosensor strain that produces violacein in the presence of exogenous AI-1, suggest that EMPM reduced violacein production in C. violaceum 12472 by interfering with the AI-1 synthesis. In contrast, capsaicin incremented violacein synthesis in strain 12472, but experiments with strain CV026 revealed that capsaicin does not function as an analog of AI-1. Biofilm formation was increased in EMPM presence, being remarkably superior in P. aeruginosa cultivated at 30 ºC, as opposed to cultivation at 37 ºC. Similarly, capsaicin induced biofilm formation in S. liquefaciens (37 ºC) and P. aeruginosa (30 ºC). However, capsaicin did not affect biofilm formation on S. liquefaciens cultured at 30 ºC, neither on P. aeruginosa at 37 ºC. These results show that violacein production in C. violaceum ATCC 12472 is inhibited by EMPM, but not by capsaicin. In general, EMPM and capsaicin did not inhibit biofilm formation in S. liquefaciens MG1 neither in P. aeruginosa PAO1. More studies are necessary to elucidate the mechanisms by which EMPM and capsaicin affect the studied phenotypes in this work

Detection of virus Alfalfa mosaic virus in pepper plant inifected and estimate the total protein of different varieties of plant capsicum Annuuml infected with the some virus

Mosaic symptoms were observed on pepper plants in Riyadh region [Wasil fields], Saudi Arabia. Out of 16 plant species mechanically inoculated with sap prepared from leaves of infected pepper plants in 0.1 M potassium phosphate buffer, pH 7.0,13 plant species were infected and exhibited external symptoms. These included: Chenopodlum amaranticolor Goste and Ryen., C. quince, Capsicum annuum L Datura stramonium, Gompbrena globosa L, Lactuca romana, Lycopersicon esculentum Mill., cultivar Sultana, Medlcago sativa L, Solanum melongena L. cultivar Black beauty, Solanum nlgrum, Nicotians glutinosa L., N. tadaccum, and Pbaseolus vulgaris L. cultivar Green beans. CucurUta pepo L., and Cucumis sativus L. did not show symptoms. The properties of virus in the infective sap were as follows: Thermal Inactivation point [TIP] was between GOTO0 C, dilution end point [DEP] was between 10[3] -10[4] and the longevity In Vitro [IV] was between 2-4 days. ELISA indicated that the virus was alfalfa mosaic virus [AMV]. Inoculation of some pepper cultivars with this AMV isolate resulted in external virus symptoms which were variable among the different inoculated pepper cultivars. Determination of the total protein in the different pepper cultivars revealed higher protein contents in the inoculated cultivars compared to those which were not inoculated with AMV. Seven plant species [Nlcotiana glutinosa L., Datura stramonium L, Chenopodium amaranticolor tost and Ryen, Gomphrena globosa L, Capsicum annuum L., Solanum nlgrum L., Phaseolus vulgaris L.] out of 11 plant species mechanically inoculated with the virus isolate, and showed AMV-like symptoms on them. ELISA indicated that the naturally infected pepper plant as well as the seven inoculated host plants that showed different symptoms, and were all positive to AMV. Four pepper varieties were infected with the virus and that the effect of the virus varied for the different cultivars with respect to the type and severity of symptoms expressed on them and which included mosaic, yellow mosaic, calico, mottle, leaf curl and deformation, cupping, and necrosis of the interveinal areas of lamina in some pepper cultivars. ELISA also indicated that it is not necessary that the severity of symptoms and virus concentration in the infected plants are always directly proportional

Evaluación de la germinación y crecimiento de Plántula de Chiltepín -Capsicum annuum L variedad glabriusculum- en invernadero / Evaluation of germination and seedling Growth of Chiltepín -Capsicum annuum L variedad glabriusculum- greenhouse

The chiltepin is one of the natural resources of the sinaloense saw, which reaches a commercial value of $100.00 mexican pesos for 250 g approximately, due to the fact that its crop implies penetrating in the low caducifolia jungle and crossing kilometeres to be able to obtain it, in addition the persons of the region who collect it obtain the resource of an irrational way extracting the plant in its entirety from the root, which causes a minor production in the following season of crop. Due to the fact that it is a native plant of the highland region and that the conditions of germination of the seed are achieved when the fruit is consumed by birds and passes for its digestive tract, it is a plant difficult to cultivate. By what preliminary studies were realized to evaluate the germinative percentage of the plant of chiltepín. There was placed to the shade for one month a whole of 2 000 seeds distributed in 4 charolas by 500 seeds each one. To stimulate the germination the hormone of growth was used giberelina. The beginning of the germination was observed to 8 days, reaching a month an average height of 6.5 cm. The percentage of germination that was reached under these conditions is 97 % (in other studies it has been achieved to obtain in the laboratory up to 57 % of germination), which indicates that in the laboratory it is feasible to cultivate it in a favorable way. It is necessary to realize researches related to the growth, development and establishment of the culture of chiltepín to generate in the region economic resources that derive from this activity.

El chiltepín es uno de los recursos naturales de la sierra sinaloense, el cual alcanza un valor comercial de $100.00 pesos mexicanos por 250 g aproximadamente, ya que su cosecha implica internarse en la selva baja caducifolia y recorrer kilómetros para poder obtenerlo, además las personas de la región que lo colectan lo obtienen sin ninguna técnica, pues extraen la planta en su totalidad desde la raíz, lo que ocasiona una menor producción en la siguiente temporada de cosecha. El chiltepín es difícil de cultivar, debido a que es una planta nativa de la región serrana y a que las condiciones de germinación de la semilla se logran cuando el fruto es ingerido por aves y pasa por su tracto digestivo. Por ello se realizaron estudios preliminares para evaluar el porcentaje germinativo de esta planta. Se colocaron a la sombra, por un mes, un total de 2 000 semillas, distribuidas en 4 charolas con 500 semillas cada una. Para estimular la germinación se empleó la hormona de crecimiento giberalina. El inicio de la germinación se observó a los 8 días, alcanzando al mes una talla promedio de 6,5 cm de altura. El porcentaje de germinación que se alcanzó bajo estas condiciones fue de 97% (en otros estudios se ha logrado obtener en el laboratorio hasta un 57% de germinación), lo cual indica que en el laboratorio es factible cultivarlo de manera favorable. Es necesario realizar investigaciones relacionadas con el crecimiento, desarrollo y establecimiento del cultivo de chiltepín para generar en la región recursos económicos que deriven de esta actividad.

Atividade antimicrobiana do gênero Capsicum / Antimicrobial activity of the genus Capsicum

Avaliou-se a atividade antimicrobiana do extrato bruto (EB) e frações hexânica (FH), clorofórmica (FC) e acetato de etila (FA) das pimentas malagueta (C. frutescens), cambuci (C.bactum var. pendulum), cumari (C.baccatum var praetermissum) e pimentão magali (C. annuum var. annuum). O EB foi obtido por extração líquido-líquido em solução hidro-alcoólica (etanol 96ºGL) seguida de fracionamento pelo sistema de solventes com grau de polaridade crescente, resultando em FH, FC e FA.(...) O pimentão obteve apenas atividade bacteriostática frente a seis bactérias. Estes resultados demonstram que a pimenta cumari, cambuci e malagueta podem ser utilizadas como agentes conservantes naturais em alimentos.

Consumption of red-hot chili pepper increases symptoms in patients with acute anal fissures. A prospective, randomized, placebo-controlled, double blind, crossover trial / Efeito da pimenta vermelha nos sintomas de pacientes com fissuras anais agudas

BACKGROUND: Red-hot chili pepper and other spices have been blamed for causing or exacerbating symptoms of anal pathologies like anal fissure and hemorrhoids. AIM: To determine if consumption of chilies increases symptoms of acute anal fissures. METHODS: Individual patients were randomized to receive capsules containing chili or placebo for one week in addition to analgesics and fiber supplement. Patients were asked to note score for symptoms like pain, anal burning, and pruritus during the study period. After 1 week, cross over treatment was administered to the same group of patients with the same methodology and results were noted at the end of 2 weeks. RESULTS: Fifty subjects were recruited for this study. Forty three of them completed the trial (22 in the chili group and 21 in the placebo group). The daily mean pain score was significantly lower in the placebo group in the study period. Score 2.05 in chili group and 0.97 in placebo group. There was a significant burning sensation experienced by the patients in the chili group (score 1.85 for the chili group vs 0.71 for the placebo group). Patient’s mean recorded improvement score was significantly higher after taking placebo. Eighty one point three percent patients preferred placebo while 13.9 percent preferred chilies. Two patients had no preference. CONCLUSION: Consumption of chili does increase the symptoms of acute anal fissure and reduces patient compliance.

RACIONAL: A pimenta vermelha e outras especiarias têm sido responsabilizadas por agravar a sintomatologia das doenças anais, tais como fissuras e hemorróidas. OBJETIVO: Determinar se o consumo de pimentas vermelhas aumentaria os sintomas em fissuras anais agudas. MÉTODOS: Pacientes foram recrutados e randomizados para receber cápsulas contendo pimenta ou placebos por 1 semana, somadas a analgésicos e suplementos de fibras. Foi solicitado que anotassem um escore de sintomas, tais como dor, queimação anal, prurido durante o período de estudo. Após 1 semana o tratamento foi cruzado e administrado ao mesmo grupo de pacientes com a mesma metodologia e os resultados foram anotados ao final de duas semanas. RESULTADOS: Cinqüenta pacientes foram selecionados e 43 completaram o estudo (22 no grupo pimenta e 23 no grupo placebo). O escore médio diário de dor foi significativamente mais baixo (2,05 no grupo pimenta e 0,97 no grupo placebo). A sensação de queimação foi sentida de modo significativo no grupo pimenta (1,85 para o grupo pimenta vs 0,71 para o grupo placebo). O escore de melhora dos sintomas foi significantemente alto após tomar o placebo. Oitenta e um virgula três porcento dos pacientes preferiram tomar placebo contra 13,9 por cento que preferiram pimenta. Dois pacientes não referiram preferências. CONCLUSÃO: O consumo de pimentas agrava os sintomas de fissuras anais agudas.

Epidemiological and etiological study of oral submucous fibrosis among gutkha chewers of Patna, Bihar, India.

An etiological and epidemiological study of oral submucous fibrosis (OSMF) has been done in Patna, Bihar. Total 157 cases of OSMF and 135 control subjects were selected for study in the period of 2002-2004. It was observed that Male:Female ratio was 2.7:1. The youngest case of OSMF was 11 year old and the oldest one was 54 years of age. Maximum number of cases were belonging to 21-40 years of age and they were belonging to low or middle socioeconomic class. Most of the OSMF cases used heavy spices and chillies, where as control mild spices and chillies. Gutkha was the most commonly used by the OSMF cases only 3 per cent did not use any gutkha or other areca nut product where as 80 per cent control did not have any chewing habit. The OSMF cases used gutkha and other products 2-10 pouches per day and kept in the mouth for 2-10 minutes and they were using since 2-4 years. Most of the OSMF cases kept gutkha in the buccal vestibule or they chewed and swallowed it, only a small number of patients chewed and spitted it out. It was also observed that OSMF developed on one side of the buccal vestibule where they kept the chew and other side was normal.

Effect of chili pepper (Capsicum frutescens) ingestion on plasma glucose response and metabolic rate in Thai women.

OBJECTIVES: To evaluate the effect of 5 g fresh chili pepper (CAP) on glucose response after a glucose drink and metabolic rate (MR) in Thai women. MATERIAL AND METHOD: The glucose response after a glucose drink was evaluated in 10 healthy women. The plasma glucose levels at 0, 15, 30 and 60 min after glucose load with and without 5 g fresh CAP were compared. Evaluation of MR was performed in an additional 12 subjects. MR was measured by the ventilated-hood indirect calorimetry system before and for 60 min after CAP ingestion. RESULTS: The rise of plasma glucose at 30 min after CAP ingestion was significantly lower than the rise of plasma glucose after a plain glucose drink by 20.6 per cent (p < 0.01). On the other hand, the CAP ingestion significantly increased MR above resting MR. Moreover, MR immediately increased by 20 per cent within a few minutes after CAP ingestion and showed a remarkable increase of 7.2-17.4 per cent from baseline for 11 min. The significance of thermogenic change was present up to 30 min (p < 0.05). CONCLUSIONS: Within 30 min after consumption of 5 g of Capsicum frutescens, plasma glucose level during the absorption period was significantly inhibited. The metabolic rate was also immediately increased after ingestion and sustained up to 30 min.

Creencias sobre el consumo de chile y la salud en la ciudad de México / Chili pepper consumption beliefs and health in Mexico City

En México el consumo de chile constituye una tradición cultural y a sus efectos sobre la salud se les han atribuido, empíricamente, características controvertidas. En este trabajo se describen las creencias sobre el consumo de chile y la salud, en dos grupos de residentes de la Ciudad de México. Los resultados ratifican, por una parte, la gran variedad de efectos benéficos y/o nocivos que se asocian al consumo de este alimento y, por la otra, demuestran que los niveles de consumo no están relacionados con las creencias que se tienen en cuanto a su impacto en la salud

Eating chili peppers is a cultural tradition in Mexico. Controversial characteristics have been empirically associated to chili pepper consumption and human health. In this paper, the beliefs about the health impacts of chili pepper consumption in two independent groups of Mexico City residents are described. The results confirm, on the one hand, that there is a wide variety of health benefits and damages associated with chili pepper consumption, but on the other hand, that the levels of chili pepper consumption are not related to beliefs about its human health impact.