Vernonia condensata

The present study evaluated the antioxidant potential of Vernonia condensata Baker (Asteraceae). Dried and powdered leaves were exhaustively extracted with ethanol by static maceration followed by partition to obtain the hexane, dichloromethane, ethyl acetate, and butanol fractions. Total phenols and flavonoids contents were determined through spectrophotometry and flavonoids were identified by HPLC-DAD system. The antioxidant activity was assessed by DPPH radical scavenging activity, TLC-bioautography, reducing power of Fe+3, phosphomolybdenum, and TBA assays. The total phenolic content and total flavonoids ranged from 0.19 to 23.11 g/100 g and from 0.13 to 4.10 g/100 g, respectively. The flavonoids apigenin and luteolin were identified in the ethyl acetate fraction. The IC50 of DPPH assay varied from 4.28 to 75.10 µg/mL and TLC-bioautography detected the antioxidant compounds. The reducing power of Fe+3 was 19.98 to 336.48 μg/mL, while the reaction with phosphomolybdenum ranged from 13.54% to 32.63% and 56.02% to 135.00% considering ascorbic acid and rutin as reference, respectively. At 30 mg/mL, the ethanolic extract and fractions revealed significant effect against lipid peroxidation. All these data sustain that V. condensata is an important and promising source of bioactive substances with antioxidant activity

New Approaches to Clarify Antinociceptive and Anti-Inflammatory Effects of the Ethanol Extract from Vernonia condensata Leaves

The present study was aimed at evaluating the antinociceptive and anti-inflammatory effects of the ethanol extract from Vernonia condensata leaves in animal models, in order to afford a better understanding of these properties. The extract reduced the number of abdominal contortions at doses of 100 (51.00 ± 3.00), 200 (42.00 ± 2.98) and 400 mg/kg (39.00 ± 4.00). In formalin tests, a significant reduction in the licking time (p < 0.01) was observed in the first phase by 25.14 (200 mg/kg = 51.50 ± 4.44) and 31.15% (400 mg/kg = 48.00 ± 4.37). The doses of 100 (43.37 ± 5.15), 200 (34.62 ± 4.16) and 400 mg/kg (28.37 ± 3.98) inhibited (p < 0.001) the second phase. After 60 and 90 min of treatment, a dose of 400 mg/kg (10.13 ± 0.39 and 11.14 ± 1.33, respectively) increased the latency time. Doses of 200 and 400 mg/kg potentiated the sleeping time induced by diazepam, pentobarbital and meprobamate. The extracts (100, 200 and 400 mg/kg) showed anti-inflammatory effects by a decrease in paw edema. The extracts also reduced the exudate volume at the doses of 200 and 400 mg/kg. The leukocyte migration had significant effect (p < 0.001) at doses of 100, 200 and 400 mg/kg. The completion of additional experiments in the investigation of the antinociceptive and anti-inflammatory activities of V. condensata allowed a better understanding of the central and peripheral mechanisms involved

Propriedades biológicas e toxicológicas de Bauhinia forficata Link (Fabaceae)

Bauhinia forficata Link (Fabaceae), known as "pata-de-vaca", is a medicinal plant native in South America, traditionally used as hypoglycemic, diuretic, hypocholesterolemic, and in the treatment of cystitis, intestinal parasites, elephantiasis and other organic disturbs. These disorders are associated with oxidative stress and cellular damage. The major secondary metabolites present in this species are phenolic compounds, particularly flavonoids. In this context, the aims of this study were to evaluate the antioxidant, antibacterial and genotoxic activities of B. forficata leaves and to determine the total phenols and flavonoids contents. Dried and powdered plant material was subjected to static maceration in ethanol followed by liquid/liquid partition to obtain the ethanol extract (EE) and the hexane (HF), dichloromethane (DF), ethyl acetate (EF) and butanol (BF) fractions. The total phenols and flavonoids contents were determined by spectrophotometry using gallic acid and rutin calibration curves, respectively. The antioxidant activity was evaluated by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging, the ferric reducing power and the β-carotene bleaching assays. The antibacterial activity was investigated by determining the 100% Minimal Inhibitory Concentration (MIC100) using the broth microdilution according to Clinical Laboratory Standards Institute (CLSI) recommendations against seven ATCC reference strains. After that, the bactericidal or bacteriostatic pharmacological effect was established and the Minimal Bactericidal Concentration (MBC) was also determined. The genotoxic potential was assessed by the comet assay using HepG2 cells. Analyses were performed in triplicate and the results presented as mean ± standard deviation, when appropriate. Data were statistically analyzed by one-way ANOVA followed by Tukey’s post-test (p < 0.05). The total phenolic and flavonoid contents ranged from 9.20 ± 0.87 to 87.35 ± 0.92 mg/g gallic acid equivalents, and from 2.51 ± 0.06 to 56.76 ± 0.81 mg/g rutin equivalents, respectively. The Effective Concentration 50% values in the DPPH and ferric reducing power assays were 27.95 ± 0.33 to 193.62 ± 1.12 μg/mL, and 21.12 ± 0.52 to 328.45 ± 3.23 μg/mL, respectively. The percentage inhibition of lipid peroxidation obtained by β-carotene bleaching method ranged from 26.80 ± 2.26 to 67.07 ± 1.48, 36.30 ± 5.38 to 73.66 ± 3.91 and 48.70 ± 5.08 to 81.93 ± 3.45 at 250, 500 and 1000 μg/mL concentrations, in that order. The EF was active against Staphylococcus aureus ATCC 29213 and ATCC 6538, with MIC100 and MBC values of 2.5 mg/mL and 5 mg/mL, and 5 mg/mL and > 5 mg/mL, respectively, showing bacteriostatic effect. The EE induced significant genetic damage to HepG2 cells by the comet assay at concentrations of 125 and 250 μg/mL. The results of this study indicate that B. forficata contains phenolic compounds, including flavonoids, possessing antioxidant and antibacterial effects. The genetic damage revealed by EE requires additional studies to confirm its genotoxic potential.Bauhinia forficata Link (Fabaceae), conhecida como pata-de-vaca, é uma planta medicinal nativa da América do Sul, tradicionalmente usada como hipoglicemiante, diurética, hipocolesterolêmica e no tratamento de cistite, parasitoses intestinais, elefantíase e outros distúrbios orgânicos. Essas disfunções estão associadas ao estresse oxidativo e dano celular. Os principais metabólitos especiais presentes nesta espécie são as substâncias fenólicas, em particular os flavonoides. Neste contexto, o objetivo do presente estudo foi avaliar as atividades antioxidante, antibacteriana e genotóxica das folhas de B. forficata, bem como determinar o conteúdo de fenóis e flavonoides totais. O material vegetal seco e pulverizado foi submetido à maceração estática em etanol, seguido de partição líquido/líquido para obtenção do extrato etanólico (EE) e das frações em hexano (FH), diclorometano (FD), acetato de etila (FA) e butanol (FB). Os teores de fenóis e flavonoides totais foram determinados por espectrofotometria utilizando as curvas de calibração do ácido gálico e da rutina, respectivamente. A atividade antioxidante foi avaliada pelos ensaios do sequestro do radical livre 2,2-difenil-1-picril-hicrazila (DPPH•), poder de redução do ferro e cooxidação do β- caroteno/ácido linoleico. A atividade antibacteriana foi investigada por meio da determinação da Concentração Inibitória Mínima 100% (CIM100) pelo método de microdiluição em caldo segundo recomendações do Clinical Laboratory Standards Institute (CLSI) frente a sete amostras de referência ATCC. Em seguida, procedeu-se ao estabelecimento do efeito farmacológico bactericida ou bacteriostático e à determinação da Concentração Bactericida Mínima (CBM). O potencial genotóxico foi avaliado pelo ensaio do cometa utilizando células HepG2. As análises foram realizadas em triplicata e os resultados apresentados como média ± desvio-padrão, quando pertinente. Os dados foram submetidos à Análise de Variância seguida do pós-teste de Tukey (p < 0,05). Os teores de fenóis e flavonoides totais variaram de 9,20 ± 0,87 a 87,35 ± 0,92 mg/g em equivalentes de ácido gálico e de 2,51 ± 0,06 a 56,76 ± 0,81 mg/g em equivalentes de rutina, respectivamente. Os valores das Concentrações Efetivas 50% obtidos nos ensaios do DPPH• e poder de redução do ferro foram de 27,95 ± 0,33 a 193,62 ± 1,12 μg/mL e de 21,12 ± 0,52 a 328,45 ± 3,23 μg/mL, respectivamente. A porcentagem de inibição da peroxidação lipídica obtida pelo ensaio do β-caroteno/ácido linoleico variou de 26,80 ± 2,26 a 67,07 ± 1,48, de 36,30 ± 5,38 a 73,66 ± 3,91 e de 48,70 ± 5,08 a 81,93 ± 3,45 nas concentrações de 250, 500 e 1000 μg/mL, nessa ordem. A FA foi ativa frente à Staphylococcus aureus ATCC 29213 e ATCC 6538 testadas, com valores de CIM100 e CBM de 2,5 mg/mL e 5 mg/mL, e de 5 mg/mL e > 5 mg/mL, respectivamente, revelando efeito bacteriostático. O EE induziu dano genético significativo às células HepG2 pelo ensaio do cometa nas concentrações de 125 e 250 μg/mL. Os resultados desse estudo indicam que B. forficata possui substâncias fenólicas, incluindo flavonoides, demonstrando atividades antioxidante e antibacteriana. O dano genético revelado pelo EE requer estudos adicionais para a confirmação de seu potencial genotóxico

Teores de fenóis totais e flavonoides e avaliação da atividade antioxidante de Baccharis trimera (Less.) DC. (Asteraceae)

O presente trabalho teve como objetivo detectar a variação nos teores de fenois totais e flavonoides e na atividade antioxidante em amostras de B. trimera. Amostras secas e pulverizadas foram submetidas à extração por maceração estática para obtenção dos extratos hexânico, em acetato de etila e etanólico. Prospecção fitoquímica e avaliação dos teores de constituintes fenólicos e da atividade antioxidante foram realizadas. Os dados foram demonstrados como média ± desvio padrão e análise de variância seguida de teste de Tukey foi utilizada para medir o grau de significância (p < 0,05). Flavonoides, taninos, cumarinas, terpenoides e esteroides, alcaloides e antraquinonas foram detectados nas amostras. Os teores de flavonoides totais variaram entre 1,99 ± 0,29 a 5,20 ± 0,31 g/100g, enquanto os fenóis totais foram de 1,56 ± 0,01 a 11,09 ± 0,13 g/100g. Os extratos produziram CE50 entre 35,65 ± 0,74 e 242,74 ± 6,49 µg/mL. Os resultados indicam que o uso de solventes de diferentes polaridades no processo de extração é uma importante estratégia para detectar variação nos teores de fenois totais e falvonoides e na atividade antioxidante em amostras de B. trimera

Effect of lung recruitment and titrated Positive End-Expiratory Pressure (PEEP) vs low PEEP on mortality in patients with acute respiratory distress syndrome - A randomized clinical trial

IMPORTANCE: The effects of recruitment maneuvers and positive end-expiratory pressure (PEEP) titration on clinical outcomes in patients with acute respiratory distress syndrome (ARDS) remain uncertain. OBJECTIVE: To determine if lung recruitment associated with PEEP titration according to the best respiratory-system compliance decreases 28-day mortality of patients with moderate to severe ARDS compared with a conventional low-PEEP strategy. DESIGN, SETTING, AND PARTICIPANTS: Multicenter, randomized trial conducted at 120 intensive care units (ICUs) from 9 countries from November 17, 2011, through April 25, 2017, enrolling adults with moderate to severe ARDS. INTERVENTIONS: An experimental strategy with a lung recruitment maneuver and PEEP titration according to the best respiratory-system compliance (n = 501; experimental group) or a control strategy of low PEEP (n = 509). All patients received volume-assist control mode until weaning. MAIN OUTCOMES AND MEASURES: The primary outcome was all-cause mortality until 28 days. Secondary outcomes were length of ICU and hospital stay; ventilator-free days through day 28; pneumothorax requiring drainage within 7 days; barotrauma within 7 days; and ICU, in-hospital, and 6-month mortality. RESULTS: A total of 1010 patients (37.5% female; mean [SD] age, 50.9 [17.4] years) were enrolled and followed up. At 28 days, 277 of 501 patients (55.3%) in the experimental group and 251 of 509 patients (49.3%) in the control group had died (hazard ratio [HR], 1.20; 95% CI, 1.01 to 1.42; P = .041). Compared with the control group, the experimental group strategy increased 6-month mortality (65.3% vs 59.9%; HR, 1.18; 95% CI, 1.01 to 1.38; P = .04), decreased the number of mean ventilator-free days (5.3 vs 6.4; difference, −1.1; 95% CI, −2.1 to −0.1; P = .03), increased the risk of pneumothorax requiring drainage (3.2% vs 1.2%; difference, 2.0%; 95% CI, 0.0% to 4.0%; P = .03), and the risk of barotrauma (5.6% vs 1.6%; difference, 4.0%; 95% CI, 1.5% to 6.5%; P = .001). There were no significant differences in the length of ICU stay, length of hospital stay, ICU mortality, and in-hospital mortality. CONCLUSIONS AND RELEVANCE: In patients with moderate to severe ARDS, a strategy with lung recruitment and titrated PEEP compared with low PEEP increased 28-day all-cause mortality. These findings do not support the routine use of lung recruitment maneuver and PEEP titration in these patients. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01374022