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Context: Buchenavia tetraphylla (Aubl.) RA Howard (Combretaceae: Combretoideae) is an ethnomedicinal plant with reported antifungal action., Objective: This study evaluates the antimicrobial activity of B. tetraphylla leaf extracts against clinical isolates of Candida albicans. The morphological alterations, combinatory effects with fluconazole and the cytotoxicity of the active extract were analyzed., Materials and Methods: Extracts were obtained using different solvents (hexane: BTHE; chloroform: BTCE; ethyl acetate: BTEE; and methanol: BTME). Antimicrobial activity was determined by the broth microdilution method using nine strains of C. albicans isolated from vaginal secretions and one standard strain (UFPEDA 1007)., Results: All extracts showed anti-C. albicans activity, including against the azole-resistant strains. The MIC values ranged from 156 to 2500 μg/mL for the BTHE; 156 to 1250 μg/mL for the BTCE; 625 to 1250 μg/mL for the BTME and 625 μg/mL to 2500 μg/mL for the BTEE. BTME showed the best anti-C. albicans activity. This extract demonstrated additive/synergistic interactions with fluconazole. Scanning electron microscopy analysis suggested that the BTME interferes with the cell division and development of C. albicans. BTME showed IC 50 values of 981 and 3935 μg/mL, against J774 macrophages and human erythrocytes, respectively. This extract also enhanced the production of nitric oxide by J774 macrophages., Discussion and Conclusion: Buchenavia tetraphylla methanolic extract (BTME) is a great source of antimicrobial compounds that are able to enhance the action of fluconazole against different C. albicans strains; this action seems related to inhibition of cell division.

Several plant-derived compounds have been screened by antioxidant assays, but many of these results are questionable, since they do not evaluate the pharmacologic parameters. In fact, the development of better antioxidants stills a great challenge. In vitro cell-based assays have been employed to assess the antioxidant effect of various compounds at subcellular level. Cell-based assays can also reveal compounds able to enhance the antioxidant pathways, but without direct radical scavenging action (which could not be detected by traditional assays). These methodologies are general of easy implementation and reproducible making them suitable for the early stages of drug discovery. Hydrogen peroxide, a nonradical derivative of oxygen, can be employed as an oxidative agent in these assays due its biochemical properties (presence of all biological systems, solubility) and capacity to induce cell death. Truthfully, if their limitations are understood (such as difference on cell metabolism when in in vitro conditions), these cell-based assays can provide useful information about the pathways involved in the protective effects of phytochemicals against cell death induced by oxidative stress, which can be exploited to develop new therapeutic approaches.

Epilepsy is a disorder of the central nervous system characterized by recurrent seizures. It is a very common disease in which approximately 30% of patients do not respond favorably to treatment with anticonvulsants. Oxidative stress is associated with neuronal damage arising from epileptic seizures. The present study investigated the possible anticonvulsant and antioxidant effects of a leaf extract of Vitis labrusca in an animal model of seizures induced by pentylenetetrazole (PTZ). The animals received injections of V. labrusca extract (10, 30 and 100 mg/kg) or vehicle and, 30 minutes later, they received an injection of PTZ, and were then observed for 30 minutes. The latency time and tonic—clonic seizure time were registered. Oxidative damage in lipids and proteins was quantified in the cerebellum, cerebral cortex and hippocampus. It was observed that the leaf extract were capable of reducing lipid peroxidation and protein oxidation caused by PTZ at all doses tested.

An increasing number of biological activities presented by medicinal plants has been investigated over the years, and they are used in the search for new substances with lower side effects. Eugenia uniflora L. and Eugenia malaccensis L. (Myrtaceae) have many folk uses in various countries. This current study was designed to quantify the polyphenols and flavonoids contents and evaluate the immunomodulatory, antioxidant, and cytotoxic potentials of fractions from E. uniflora L. and E. malaccensis L. It was observed that the polyphenol content was higher in ethyl acetate fractions. These fractions have high antioxidant potential. E. malaccensis L. seeds showed the largest DPPH radical scavenger capacity (EC50 = 22.62). The fractions of E. malaccensis L. leaves showed lower antioxidant capacity. The samples did not alter the profile of proinflammatory cytokines and nitric oxide release. The results indicate that species of the family Myrtaceae are rich in compounds with antioxidant capacity, which can help reduce the inflammatory response.

Epilepsy, which is one of the most common neurological disorders, involves the occurrence of spontaneous and recurrent seizures that alter the performance of the brain and affect several sensory and behavioral functions. Oxidative damage has been associated with post-seizure neuronal injury, thereby increasing an individual's susceptibility to the occurrence of neurodegenerative disorders. The present study investigated the possible anticonvulsive and neuroprotective effects of organic and conventional yerba mate (Ilex paraguariensis), a plant rich in polyphenols, on pentylenetetrazol (PTZ)-induced seizures in Wistar rats. The behavioral and polyphenolic profiles of the yerba mate samples were also evaluated. Infusions of yerba mate (50mg/kg) or distilled water were given to rats for fifteen days by oral gavage. On the 15th day the animals were subjected to open field test, and exploratory behavior was assessed. Subsequently, 60mg/kg PTZ (i.p.) was administered, and animals were observed for the appearance of convulsions for 30min. Latency for the first seizure, tonic-clonic and generalized seizures time, frequency of seizures and mortality induced by PTZ were recorded. The animals were then sacrificed, and the cerebellum, cerebral cortex and hippocampus were quickly removed and frozen to study the neuroprotective effects of yerba mate. The oxidative damage in lipids and proteins, nitric oxide levels, the activities of the antioxidant enzymes superoxide dismutase (Sod) and catalase (Cat) and non-enzymatic cellular defense (sulfhydryl protein) were quantified in all the tissues. The results showed that organic and conventional yerba mate infusions were able to reduce the frequency of seizures when compared to the PTZ group. Besides, organic yerba mate infusion decreases the tonic-clonic seizures time in relation to the PTZ group. It was also shown that organic and conventional yerba mate infusions reduced the oxidative damage in lipids and proteins and nitric oxide levels and prevented the decrease in Sod and Cat activities and sulfhydryl protein content when compared to the PTZ group in all the CNS tissues assayed. Organic and conventional yerba mate commercial samples did not change the behavior (locomotion, exploration or anxiety) of the treated animals. In both organic and conventional infusions, the presence of the polyphenols rutin, chlorogenic acid and their acyl derivatives were detected, which could be associated with the biological effects observed. These data indicate that yerba mate may provide new perspectives for the development of therapeutic approaches with natural compounds in the pharmaceutical area, both to reduce the convulsions' frequency and to minimize the neuronal damage associated with recurrent seizures., (Copyright © 2012 Elsevier Inc. All rights reserved.)

This study evaluated the antibacterial activity of Anadenanthera colubrina, Libidibia ferrea and Pityrocarpa moniliformis fruit extracts against clinical strains of Staphylococcus aureus. The samples were active for all S. aureus strains (minimum inhibitory concentration: 0.38-3.13 mg mL⁻¹), including the multiresistant strain. The morphological changes suggested the cell wall as the main action target. The treated-cells also lose their ability to form aggregates. The analysis suggests cell wall impairment, which causes the loss of viability and death. This study showed for the first time the morphologic alterations involved in the anti-S. aureus action of fruits of A. colubrina, L. ferrea and P. moniliformis. These findings indicated that these fruit extracts are sources of bioactive compounds that can be used as antibacterial agents.

Epilepsy is the most common neurological disorder worldwide. Studies have shown that recurrent seizures may increase the concentration of reactive oxygen species, which can lead to oxidative stress and neuronal damage. These seizures result in substantial deleterious effects on an individual's health. Organic and conventional grape juices are rich in polyphenols, compounds with important antioxidant activity. However, these juices could have differences in their polyphenol content. The aim of this study was to investigate the neuroprotective and anticonvulsant effects of organic and conventional grape juice treatments in Wistar rats against pentylenetetrazole (a convulsant drug)-induced damage. In addition, we evaluated potential behavioral changes in rats treated with the juices and the polyphenolic profile of those samples. Animals (n=16 in each group) received treatment with saline, organic or conventional grape juice for 17 days. On the eighteenth day, behavioral changes were evaluated by an open field test. Afterwards, half of the rats from each group received pentylenetetrazole and were observed for 30 min to evaluate possible seizure characteristics. The animals were subsequently killed by decapitation and their hippocampus, cerebellum and cerebral cortex tissues were isolated. The results of this study showed that neither organic nor conventional grape juice altered the behavior parameters, and no statistical differences were observed in the seizure characteristics of the groups. Nevertheless, both juice types were able to protect from lipid and protein oxidative damage, decrease nitric oxide content and increase enzymatic (superoxide dismutase and catalase) and non-enzymatic (sulfhydryl protein) antioxidant defenses in brain tissues following pentylenetetrazole-induced seizures. In general, organic juice showed superior results in each test, probably due to its higher polyphenol content relative to conventional juice. These results indicate that grape juices can provide further insight into natural neuroprotective compounds and may lead to the development of new therapeutic strategies for epileptic patients., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Hemagglutinating activity has been associated to presence of lectin, carbohydrate-binding proteins. In this work Crataeva tapia bark lectin (CrataBL) was purified in milligram quantities (28 mg per g of bark) by ion exchange chromatography. The lectin was thermo-stable, ion-independent and N-terminal sequence analysis demonstrated similarity with miraculin and miraculin-like proteins (plant defensive proteins). Glycosylated nature of CrataBL was revealed using glycoprotein staining (periodic acid-Schiff's reagent), positive for polypeptides of apparent molecular masses 21 and 40 kDa on SDS-PAGE. Gel diffusion assay showed that glucose/mannose isolectins from Cratylia mollis recognized CrataBL glycan moiety. CrataBL hemagglutinating activity was inhibited by glycoproteins and CrataBL immobilized on cyanogen bromide-activated sepharose 4B (1 mL) bound 0.54 mg of glycoprotein (casein, fetuin and ovalbumin) per cycle. CrataBL was an insecticide agent against Nasutitermes corniger workers (termite that attack woods) with LC₅₀ of 0.475 mg mL⁻¹ for 6 days., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

This study evaluated the antimicrobial and hemolytic activities and phytochemical constituents of hydroalcoholic extract and its fractions from Buchenavia tetraphylla leaves. Cyclohexane (BTCF), ethyl acetate (BTEF), and n-butanol-soluble (BTSBF) and non-soluble (BTNBF) fractions were obtained from a liquid-liquid partition of hydroalcoholic extract (BTHE) from B. tetraphylla leaves. The hemolytic activity of active fractions was checked. The BTHE inhibited the growth of Micrococcus luteus (MIC: 0.10 mg/mL), Pseudomonas aeruginosa (MIC: 0.20 mg/mL), Mycobacterium smegmatis (MIC: 0.39 mg/mL), Proteus vulgaris, and Staphylococcus aureus (MIC: 0.78 mg/mL for both). The more active fractions were BTCF and BTBSF. BTCF showed better potential to inhibit M. luteus (0.10 mg/mL), P. aeruginosa (0.20 mg/mL), S. enteritidis (0.39 mg/mL), and S. aureus (1.56 mg/mL). BTBSF showed the best results for M. luteus (0.10 mg/mL), M. smegmatis, B. subtilis (0.39 mg/mL for both), and P. vulgaris (0.10 mg/mL). The HC50 were greater than observed MIC: 20.30, 4.70 and 2.53 mg/mL, respectively, to BTBF, BTHE and BTCF, which. The phytochemical analysis detected the presence of flavanoids, triterpene, carbohydrate, and tannin. Our work showed for the first time the broad-spread antimicrobial activity of B. tetraphylla, which has nonhemolytic action, creating a new perspective on the interesting association of traditional and scientific knowledge.

Ethnopharmacological Relevance: Medicinal plants from the Caatinga, a Brazilian xeric shrubland, are used in folk medicine to treat infections. These ethnopharmacological data can contribute to obtaining new antimicrobial/antibiofilm extracts and natural product prototypes for the development of new drugs. The aim of this study was to investigate the antibiofilm and antibacterial activities of 45 aqueous extracts from 24 Caatinga plant species., Materials and Methods: The effect of aqueous extracts on planktonic cells and on biofilm formation by Staphylococcus epidermidis was studied by the OD(600) absorbance and by the crystal violet assay, respectively. Scanning electron microscopy (SEM) was used to generate comparative images of extract-treated and untreated biofilms. Chromatographic analyses were performed to characterize the active extracts., Results: The in vitro screening, at 0.4 mg/mL and 4.0mg/mL, showed 20 plants effective in preventing biofilm formation and 13 plants able to inhibit planktonic bacterial growth. SEM images demonstrated distinct profiles of bacterial adhesion, matrix production and cell morphology according to different treatments and surfaces. The phytochemical analysis of the selected active extracts indicates the polyphenols, coumarins, steroids and terpenes as possible active compounds., Conclusion: This study describes the first antibiofilm and antibacterial screening of Caatinga plants against S. epidermidis. The evaluation presented in this study confirms several ethnopharmacological reports and can be utilized to identify new antibiofilm and antibacterial products against S. epidermidis from traditional Brazilian medicine., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Solanum paniculatum L. is used commonly in Brazilian folk medicine for the treatment of liver and gastrointestinal disorders. The freeze-dried aqueous extracts (WEs) obtained from distinct parts of the plant (flowers, fruits, leaves, stems and roots) were tested to determine their antiulcer and antisecretory gastric acid activities using mice. The aqueous extracts of roots, stems and flowers inhibited gastric acid secretion in pylorus-ligated mice with ED50 values of 418, 777 and 820 mg/kg body wt. (i.d.), respectively. Extracts of leaves (0.5-2 g/kg body wt., i.d.) did not affect gastric secretion, whereas fruit extracts (0.5-2 g/kg body wt., i.d.) stimulated gastric acid secretion. The stimulatory effect of the fruit extract was inhibited by pretreatment with atropine (5 mg/kg body wt., i.m.) but not with ranitidine (80 mg/kg body wt., i.p.) suggesting that the fruit extract activates the muscarinic pathway of gastric acid secretion. In contrast, administration of the root extract into the duodenal lumen inhibited histamine- and bethanechol-induced gastric secretion in pylorus-ligated mice. In addition, the aqueous extract of roots (ED50 value, 1.2 g/kg body wt., p.o.) protected the animals against production of gastric lesions subsequent to the hypersecretion induced in mice by stress following cold restraint. This effect was not reproduced when the lesions were induced by blockade of prostaglandins synthesis via subcutaneous injection of indomethacin. Thus, antiulcer activity of the plant extracts appears to be related directly to a potent anti-secretory activity. No toxic signs were observed following administration of different extracts up to 2 g/kg body wt., p.o. Collectively, the results validate folk use of Solanum paniculatum L. plant to treat gastric disorders.