RESUMO
The comparative metabolic profiling and their biological properties of eight extracts obtained from diverse parts (leaves, flowers, roots) of the medicinal plant Flourensia fiebrigii S.F. Blake, a chemotype growing in highland areas (2750â m a.s.l.) of northwest Argentina, were investigated. The extracts were analysed by GC-MS and UHPLC-MS/MS. GC-MS analysis revealed the presence of encecalin (relative content: 24.86 %) in ethereal flower extract (EF) and this benzopyran (5.93 %) together sitosterol (11.35 %) in the bioactive ethereal leaf exudate (ELE). By UHPLC-MS/MS the main compounds identified in both samples were: limocitrin, (22.31 %), (2Z)-4,6-dihydroxy-2-[(4-hydroxy-3,5-dimethoxyphenyl)methylidene]-1-benzofuran-3-one (21.31 %), isobavachin (14.47 %), naringenin (13.50 %), and sternbin, (12.49 %). Phytocomplexes derived from aerial parts exhibited significant activity against biofilm production of Pseudomonas aeruginosa and Staphylococcus aureus, reaching inhibitions of 74.7-99.9 % with ELE (50â µg/mL). Notably, the extracts did not affect nutraceutical and environmental bacteria, suggesting a selective activity. ELE also showed the highest reactive species scavenging ability. This study provides valuable insights into the potential applications of this chemotype.
Assuntos
Asteraceae , Espectrometria de Massas em Tandem , Cromatografia Gasosa-Espectrometria de Massas , Extratos Vegetais/farmacologia , Extratos Vegetais/metabolismo , Cromatografia Líquida de Alta Pressão , Folhas de Planta/metabolismo , Asteraceae/metabolismoRESUMO
The present study evaluates the chemical compositions and antioxidant and antipathogenic properties of commercial orange (Citrus sinensis (L.) Osbeck) essential oils obtained using the cold-press method (EOP) and the cold-press method followed by steam distillation (EOPD). The chemical compositions of the volatilizable fractions, determined by gas chromatography-mass spectrometry, were similar in both samples. A relatively large amount of γ-terpinene was found in the EOPD (1.75%) as compared to the EOP (0.84%). Monoterpene hydrocarbons with limonene (90.4-89.8%) followed by myrcene (3.2-3.1%) as the main compounds comprised the principal phytochemical group. The non-volatile phenolics were eight times higher in the EOP than in the EOPD. Several assays with different specificity levels were used to study the antioxidant activity. Although both essential oils presented similar reducing capacities, the radical elimination ability was higher for the EOP. Regarding the antipathogenic properties, the EOs inhibited the biomass and cell viability of Staphylococcus aureus and Pseudomonas aeruginosa biofilms. Furthermore, both EOs similarly attenuated the production of elastase, pyocyanin, and quorum-sensing autoinducers as assessed using Gram-negative bacteria. The EOP and EOPD showed important antioxidant and antipathogenic properties, so they could represent natural alternatives to extend the shelf life of food products by preventing oxidation and contamination caused by microbial spoilage.
RESUMO
The chemical composition of three Citrus limon oils: lemon essential oil (LEO), lemon terpenes (LT) and lemon essence (LE), and their influence in the virulence factors production and motility (swarming and swimming) of two Pseudomonas aeruginosa strains (ATCC 27853 and a multidrug-resistant HT5) were investigated. The main compound, limonene, was also tested in biological assays. Eighty-four compounds, accounting for a relative peak area of 99.23%, 98.58% and 99.64%, were identified by GC/MS. Limonene (59-60%), γ-terpinene (10-11%) and ß-pinene (7-15%) were the main compounds. All lemon oils inhibited specific biofilm production and bacterial metabolic activities into biofilm in a dose-dependent manner (20-65%, in the range of 0.1-4 mg mL-1) of both strains. Besides, all samples inhibited about 50% of the elastase activity at 0.1 mg mL-1. Pyocyanin biosynthesis decreases until 64% (0.1-4 mg mL-1) for both strains. Swarming motility of P. aeruginosa ATCC 27853 was completely inhibited by 2 mg mL-1 of lemon oils. Furthermore, a decrease (29-55%, 0.1-4 mg mL-1) in the synthesis of Quorum sensing (QS) signals was observed. The oils showed higher biological activities than limonene. Hence, their ability to control the biofilm of P. aeruginosa and reduce the production of virulence factors regulated by QS makes lemon oils good candidates to be applied as preservatives in the food processing industry.
Assuntos
Antibacterianos/farmacologia , Citrus/química , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/patogenicidade , Percepção de Quorum/efeitos dos fármacos , Antibacterianos/química , Proteínas de Bactérias/metabolismo , Monoterpenos Bicíclicos/química , Monoterpenos Bicíclicos/farmacologia , Biofilmes/efeitos dos fármacos , Monoterpenos Cicloexânicos/química , Monoterpenos Cicloexânicos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Limoneno/química , Limoneno/farmacologia , Óleos Voláteis/química , Elastase Pancreática/metabolismo , Óleos de Plantas/química , Pseudomonas aeruginosa/metabolismo , Piocianina/biossíntese , Transdução de Sinais/efeitos dos fármacos , Virulência , Fatores de Virulência , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/farmacologiaRESUMO
The effect of a natural sesquiterpene ketone, 9,10-dehydrofukinone (DHF), on pathogenic Staphylococcus aureus and Pseudomonas aeruginosa strains isolated from chronic infectious processes, was the focus of the present study. Lipophilic DHF produced important antibacterial synergistic effects in association with ciprofloxacin (CPX) against two biofilm-forming strains of S. aureus HT1 (FIC=0.21) and P. aeruginosa HT5 (FIC=0.05). Hence, this mixture constitutes an excellent strategy to combat these biofilm-producing bacteria that overexpress drug efflux pumps as a resistance mechanism. Additionally, a substantial rise in beneficial Lactobacillus biofilm biomass was determined as a very significant finding of this association. Particularly, a non-pathogenic biofilm increment of 119 % was quantified when the mixture was added to a probiotic L. acidophilus ATCC SD-5212 culture. A surface activity enhanced in 71 % with respect to untreated L. acidophilus culture was also generated by the DHF and CPX association, and therefore, a glycoprotein synthesis induction mediated by the mixture is discussed. The results obtained could help in the development of new selective antibiotics. From an ecological standpoint, the present study strongly suggests that DHF is a polyfunctional organic molecule produced with a high yield in Senecio punae that exerts a positive impact on a non-pathogenic plant bacterium L. plantarum CE105.
Assuntos
Senécio/química , Sesquiterpenos/química , Compostos Orgânicos Voláteis/química , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Ciprofloxacina/farmacologia , Lactobacillus/efeitos dos fármacos , Lactobacillus/fisiologia , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/isolamento & purificação , Pseudomonas aeruginosa/fisiologia , Senécio/metabolismo , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Staphylococcus aureus/fisiologiaRESUMO
Citrus essential oils are used in food to confer flavor and aromas. The citrus essential oils have been granted as GRAS and could be used as antimicrobial additives to control bacterial quorum sensing from potential food bacterial pathogens. The chemical composition and inhibitory activity of Citrus paradisi (grapefruit) essential oils obtained by cold-pressed method (EOP) and cold-pressed method followed by steam distillation, against Pseudomonas aeruginosa were determined. The GC-MS analyses of the oil indicated the amount of the essential oil components was highest with D-limonene in both cases. However, the extraction method modified the chemical composition. EOP had higher amount of coumarins and flavonoid as well as less oxygenated terpenoids. At 0.1 mg/mL essential oils were not able to modify the bacterial development but inhibited the P. aeruginosa biofilm production between 52% and 55%, sessile viability between 45% and 48%, autoinducer production and elastase activity between 30% and 56%. Limonene was less effective at inhibiting P. aeruginosa than the essential oils, suggesting a synergistic effect of the minor components. According to our results, grapefruit essential oils could be used as a food preservative to control P. aeruginosa virulence.
Assuntos
Citrus paradisi/química , Microbiologia de Alimentos , Conservantes de Alimentos/farmacologia , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Percepção de Quorum/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Cumarínicos/análise , Cumarínicos/farmacologia , Flavonoides/análise , Flavonoides/farmacologia , Conservação de Alimentos/métodos , Conservantes de Alimentos/análise , Humanos , Limoneno/análise , Limoneno/farmacologia , Óleos Voláteis/química , Extratos Vegetais/química , Pseudomonas aeruginosa/fisiologia , Terpenos/análise , Terpenos/farmacologiaRESUMO
In this work, we intended to inhibit the biofilm synthesis and the metabolism of Gram-positive and Gram-negative bacteria using two highly available wastes (stem and marc) obtained after the manufacturing of Torrontes wine at Cafayate, Argentina. Wine wastes contain a significant amount of bioactive compounds, mainly phenolic compounds, which makes them a potential source of compounds with beneficial properties to human health, as they could inhibit the virulence of pathogenic bacteria or protect the tissue against oxidative stress. Marc and stem extracts of Torrontes wine were evaluated for their ability to inhibit the metabolism and biofilm production of Pseudomonas aeruginosa and Staphylococcus aureus strains. The phytochemical composition and antioxidant activity of these extracts were also determined. The methanol and ethyl acetate extracts, which contained the highest amount of total polyphenolic, exhibited the highest scavenging capacity of ABTS and nitric oxide and the strongest Fe3+ reducing power and exhibited the highest level of inhibition of the biofilm formation and of the metabolic activity in bacterial biofilm. We also noticed a positive correlation between phenolic compounds content, the antioxidant activity, and the anti-biofilm capacity of the winemaking wastes. These results display the potentiality of wine wastes to prevent or reduce the formation of biofilm. Moreover, their abundance makes them an attractive and affordable source of antibiofilm and antioxidant agents.
RESUMO
BACKGROUND: Chronic myelomonocytic leukemia (CMML) is the most aggressive of chronic leukemias, with short overall survival and a high transformation rate to acute leukemia. We investigated the factors related to blastic transformation in a Mexican population treated at a tertiary referral center. PATIENTS AND METHODS: The records of patients with a diagnosis of CMML from 2000 to 2015 were reviewed. A total of 54 patients were included, with a median age of 71 years and an overall survival of 16 months. The patients with incomplete data were excluded. IBM SPSS Statistics, version 21.0, software was used to perform the statistical analysis. RESULTS: The rate of blastic transformation was 33% (18 patients), and the interval time to progression was 9 months (range, 0-87 months). Comparing the patients who did not undergo blastic transformation to those who did, those with progression to acute leukemia tended to be younger (age, 58 vs. 71 years; P = .001), to have a greater peripheral blood blast count (≥ 2% vs. 0%; P = .003), and were more likely to have immature myeloid precursors circulating in the peripheral blood (94% vs. 64%; P = .02). On multivariate analysis, younger age continued to be a statistically significant factor for progression (hazard ratio, 0.97; 95% confidence interval, 0.929-0.987). CONCLUSION: Mexican patients with CMML that progressed to overt acute leukemia were considerably younger, with a higher tumor burden and short overall survival. In this population, it is important to consider more aggressive treatment at diagnosis, focusing on high-dose chemotherapy and hematopoietic stem cell transplantation within a short period.
Assuntos
Medula Óssea/patologia , Leucemia Mieloide Aguda/epidemiologia , Leucemia Mieloide Aguda/patologia , Leucemia Mielomonocítica Crônica/epidemiologia , Leucemia Mielomonocítica Crônica/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Células da Medula Óssea/patologia , Progressão da Doença , Feminino , Humanos , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/terapia , Leucemia Mielomonocítica Crônica/terapia , Contagem de Leucócitos , Leucócitos/patologia , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Vigilância da População , Análise de Sobrevida , Fatores de Tempo , Adulto JovemRESUMO
The new methylated grindelane diterpenoid, 7ß-hydroxy-8(17)-dehydrogrindelic acid (1b), together with the known 7α-hydroxy-8(17)-dehydrogrindelic acid (2a), 6-oxogrindelic acid (3a), 4ß-hydroxy-6-oxo-19-norgrindelic (4a), 19-hydroxygrindelic acid (5a), 18-hydroxygrindelic acid (6a), 4α-carboxygrindelic acid (7a), 17-hydroxygrindelic acid (8a), 6α-hydroxygrindelic acid (9a), 8,17-bisnor-8-oxagrindelic acid (10a), 7α,8α-epoxygrindelic acid (11a), and strictanonic acid (12a) as methyl esters were obtained from an Argentine collection of Grindelia chiloensis (Cornel.) Cabrera. Their structures and relative configurations were established on the basis of spectroscopic analysis. CHCl3 extract from the aerial parts and their pure compounds were evaluated for their antifungal and depigmenting effects. Methyl ester derivative of 10a (10b) exhibited a remarkable mycelial growth inhibition against Botritis cinerea with an IC50 of 13.5 µg ml-1 . While the new grindelane 1b exerted a clear color reduction of the yellow-orange pigment developed by Fusarium oxysporum against UV-induced damage.
Assuntos
Antifúngicos/isolamento & purificação , Grindelia/química , Preparações Clareadoras de Pele/isolamento & purificação , Antifúngicos/farmacologia , Diterpenos , Fusarium/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Extratos Vegetais/química , Preparações Clareadoras de Pele/farmacologiaRESUMO
Increasing chronic bacterial infections create an urgent need for new antimicrobial agents or strategies for their control. Targeting virulence is one of the alternative approaches to find new medicines to treat persistent infections due to bacteria with biofilm-phenotype which are more resistant to antibiotics than their planktonic counterparts having an extreme capacity for evading the host defences. A bioguided study of sixteen extracts from flowers and leaves of four subtropical Convolvulaceae species provided evidence of the occurrence of antipathogenic natural products active against Gram positive and negative bacteria. Particularly, volatile metabolites from Merremia dissecta creeper, a food and medicinal plant, were able to interfere with the Pseudomonas aeruginosa quorum sensing system by a strong decrease of N-acyl homoserine lactone (AHL) biosynthesis (63-75%), which attenuated the virulence factor expression like biofilm (55%) and elastase activity (up to 27%), key factors that enable the colonization and dissemination of the infection in the host. Control of the P. aeruginosa biofilm and the QS process by phytochemicals, such as (+) spathulenol, isolated from a bioactive extract of M. dissecta leaves would be a good strategy for the development of new and effective antipathogenic drugs.
RESUMO
Senecio punae Cabrera (Asteraceae-Senecioneae) is an endemic species from Puna semi-desert region of Argentina.The major compound, 4p,5p-eremophil- 7(11)9-dien-8-one, also known as dehydrofukinone (D), was isolated from the diethyl ether extract (E) of the plant. The phytochemical constituents from S. punae are presented here for the first time, as well as bioassays employing D, a molecule with versatility to carry out many different biological activities. E and D showed acute molluscicidal activity against the bilharzia vector snail Biomphalaria peregrina with LD50 values of 68.6 and 16.7 pg/mL, respectively. D exerted moderate and strong effects against promastigotes of Leishmania amazonensis and L. braziliensis, with IC5s values of 34.3?1.2 and 9.93+0.17 Ag/mL, respectively. Antibacterial effects were also found. Diethyl ether extract (E) and dehydrofukinone (D) were slightly active against Pseudomonas aeruginosa and Staphylococcus aureus at 50 and 25 tg/mL, respectively. However, D and E improved the effectiveness of oxacillin at 6 ig/mL against S. aureus growth and its biofilm, but did not affect beneficial lactobacilli strains. Synergistic effects were also measured between D (23 gg/mL) and ciprofloxacin (0.25 pg/mL) against two P. aeruginosa strains (FIC index = 0.38), as well as against two S. aureus strains (FIC indexes = 0.38 and 0.25). Finally, when 250 pg of either dehydrofukinone (D) or diethyl ether extract (E) were incorporated into the diet of the pest Oryzaephillus surinamensis, an alteration in the feeding behavior of the insect (Repellency indexes = +60 and +10, respectively) was observed.