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Background. Fruit consumption is currently considered beyond the nutritional aspects because of the important roles in disease prevention and benefits to health. The objective of this study was to characterize the chemical profile and evaluate the antioxidant and antimicrobial properties of different fractions obtained from fruit pulps of Mauritia flexuosa (MFFs). Methods. Initially, chloroform, ethyl acetate and ethanol fractions were obtained from the pulps. Quantifications of total phenols and flavonoids were performed using the methods of Folin-Ciocalteu and complexation with aluminum chloride, respectively. Standard samples were used to identify and quantify phenolic acids and flavonoids using high-performance liquid chromatography with a diode-array detector (HPLC-DAD). The antioxidant capacity of the fractions was verified by sequestration of the free radical 2,20-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid (ABTS) and iron chelating activity. The antimicrobial activity was determined using the microdilution method and the modulating activity was determined using sub-inhibitory concentrations of the fractions in association with antibiotics. Results. The chemical analyzes revealed the presence of catechin, caffeic acid, rutin, orientin, quercetin, apigenin, luteolin and kaempferol, where all are present in the ethyl acetate fraction. The fractions exhibited moderate antioxidant and antimicrobial activities against Gram-positive and Candida strains in addition to modulating the activity of conventional antibiotics. The most expressive result was obtained from the association of the chloroform fraction with cefotaxime, which produced a synergistic effect, reducing the minimum inhibitory concentration (MIC) of the antibiotic from 1,024 to 256 µg/mL. Discussion. The fractions presented a constitution rich in phenolic compounds, especially flavonoids. The data obtained demonstrated that the fractions presented moderate antioxidant activity by acting both as primary and secondary antioxidants. The fractions presented antimicrobial and antibiotic potentiating activities, being the first record of modulating effect of fractions of this species against the studied microbial strains, but failed in modulating the activity of antifungal drugs, indicating that this plant has the potential to be used in the development of therapeutic alternatives against resistant bacteria. The constitution phenolic the fractions may be responsible for their pharmacological properties in vitro. [ABSTRACT FROM AUTHOR]

Mercury is a very dangerous metal when humans come into contact with it, whether through the air or skin or by ingestion. The aim of this work was to investigate the possible effects of the ethanol extract and fractions of Lygodium venustum Sw. against mercurium chloride toxicity towards Escherichia coli strain ATCC25922. The polyphenols and flavonoids present in the extract and fractions were quantified in mg equivalent of gallic acid/g sample and mg equivalent of quercetin/g sample, respectively. The in vitro FRAP method demonstrated the antioxidant activity of the samples. The antibacterial activity of the natural products was evaluated by microdilution method and by assays to elucidate the possible cytoprotective action when combining the natural products samples and mercurium chloride, utilizing the extract and fractions at a subinhibitory concentration. The results obtained in this work indicate that the ethanol extract and fractions of L. venustum are an alternative source of natural products with cytoprotective action, where this protection is correlated with antioxidant and chelating activity, due to the presence of total phenols and flavonoids. [ABSTRACT FROM AUTHOR]

Background: Lippia alba (Mill.) N.E. Brown, popularly known as "erva-cidreira," is commonly found in northeastern Brazil. The leaves tea is used to treat digestive disturbances, nausea, cough, and bronchitis. Objective: This work reports the chemical composition and erythromycin-modifying activity by gaseous contact against Staphylococcus aureus. Materials and Methods: The leaves of L. alba were subjected to hydrodistillation, and the essential oil extracted was examined with respect to the chemical composition, by gas chromatography-mass spectrometry (GC-MS), and the essential oil extracted was evaluated for antibacterial and antibiotic-modifying activity by gaseous contact. Results: The overall yield of essential oil obtained by hydrodistillation was 0.52%. The GC-MS analysis has led to the identification of the main components: geranial (31.4%) and neral (29.5%). It was verified that the essential oil interfered with erythromycin antibiotic activity against S. aureus ATCC 25923 was enhanced (221.4%) in the presence of 12% essential oil. The 3% essential oil increased the effect against S. aureus ATCC 25923 (41.6%) and S. aureus ATCC 6538 (58.3%). Conclusion: The essential oil of L. alba influences the activity of erythromycin and may be used as an adjuvant in antibiotic therapy against respiratory tract bacterial pathogens. [ABSTRACT FROM AUTHOR]

Background: Many medicinal plant species from the Araripe Basin are widely known and used in folk medicine and for commercial manufacturing of phytotherapeutic products. Few ethnobotanical and pharmacological studies have been undertaken in this region, however, in spite of the great cultural and biological diversity found there. Materials and Methods: Extracts of 11 plant species collected from Ceará state, Brazil, were subjected to the brine shrimp lethality test in order to detect potential sources of novel cytotoxic, antitumor compounds. The larvicidal activity, based on the percentage of larval mortality, was evaluated after 24 h exposure to the treatments. Results: All species tested showed good larvicidal activity as compared to a reference compound and literature data. The extract from Vanillosmopsis arborea was the most active with an LC50 of 3.9 μg/ml. Best results were shown by Lantana montevidensis against Pseudomonas aeruginosa [minimum inhibitory concentration (MIC) 8μg/ml] and Escherichia coli (MIC 32 μg/ml), Zanthoxylum rhoifolium against E. coli (MIC, 256 μg/ml) and Staphylococcus aureus (MIC 64 μg/ml) and Croton zenhtneri against S. aureus (MIC 64 μg/ml). Conclusion: Chemical tests indicated that a wide variety of natural product classes was present in those extracts that showed significant activities in the bioassays. [ABSTRACT FROM AUTHOR]

In this work, the chemical constituents, antibacterial and modulatory activities of the essential oil of Lantana camara Linn were studied. The essential oil was extracted from the leaves of L. camara by hydrodistillation method using Clevenger's apparatus and its chemical constituents were separated and identified by GC-MS, and the relative content of each constituent was determined by area normalization. Among the 25 identified components, bicyclogermacrene (19.42%), isocaryophyllene (16.70%), valecene (12.94%) and germacrene D (12.34%) were the main constituents. The oil was examined to antibacterial and modulatory activities against the multiresistant strains of Escherichia coli and Staphylococcus aureus by microdilution test. The results show an inhibitory activity to E. coli (MIC 512 μg/ml) and S. aureus (MIC 256 μg/ml). The synergism of the essential oil and aminoglycosides was verified too, with significant reduction of MICs (7x, 1250-5 μg/ml) against E. coli. It is suggested that the essential oil of Lantana camara Linn could be used as a source of plant-derived natural products with resistance-modifying activity. [ABSTRACT FROM AUTHOR]

The article discusses a study on the in vitro phototoxic activity of methanol extracts of Croton campestris A., Ocimum gravissimum L. and Cordio verbenaceae DC. For the study, researchers bacterial strains such as Escherichia coli and Staphylococcus aureus. They found a significant phototoxic effect with the three extracts against Staphylococcus aureus but not against the Escherichia coli bacterial strain. They found that light can used for antimicrobial activity of phytoconstituents gathered from the extracts.

The leaves of Lantana montevidensis Briq. (Verbenaceae) were subjected to hydrodistillation, and the essential oil extracted was examined with respect to chemical composition, antibacterial and antibiotic modifying activity by gaseous contact. Among the 19 identified components, β-caryophyllene (31.50%), germacrene D (27.50%) and bicyclogermacrene (13.93%) were the main constituents. The essential oil volatile constituents inhibited the growth of Staphylococcus aureus and Pseudomonas aeruginosa with a MID o 0.25 and > 1 mg/L, respectively. The activity of the antibiotics gentamicin and amikacin was reinforced against S. aureus and P. aeruginosa (with a 102% of amikacin activity against P. aeruginosa) after contact with the volatile components, showing that this oil influences the activity of the antibiotic and may be used as an adjuvant in the antibiotic therapy of respiratory tract bacterial pathogens. [ABSTRACT FROM AUTHOR]

To verify the composition variation of its essential oil along 24 hours, leaves of Lantana camara Linn. of medicinal plant collection of the Department of Chemical Biology of URCA-Crato-CE, were collected every three hours during one day (of the 07:00 to 19:00 h) in April, 2008. The leaves had its oil extracted by hydro-distillation in Clevenger apparatus during three hours with two repetitions. The chemical composition analysis of the extracted essential oils was carried out in gas chromatography/mass spectroscopy. The phytochemical profile of the essential oils presented significant difference in function of the harvest. The seven most abundant were: germacrene D (24.50-6.15%), biciclogermacrene (33.32-14.27%), spathulenol (25.04-1.06%), eremophilene (20.64-1.93%), valecene (33.70-0.84%), viridiflorene (19.46%) and 1,10-di-epi-cubenol (27.93-21.32). The different result found here indicates the existence of different chemotypes of L. camara. [ABSTRACT FROM AUTHOR]

Background: Fruit consumption is currently considered beyond the nutritional aspects because of the important roles in disease prevention and benefits to health. The objective of this study was to characterize the chemical profile and evaluate the antioxidant and antimicrobial properties of different fractions obtained from fruit pulps of Mauritia flexuosa (MFFs)., Methods: Initially, chloroform, ethyl acetate and ethanol fractions were obtained from the pulps. Quantifications of total phenols and flavonoids were performed using the methods of Folin-Ciocalteu and complexation with aluminum chloride, respectively. Standard samples were used to identify and quantify phenolic acids and flavonoids using high-performance liquid chromatography with a diode-array detector (HPLC-DAD). The antioxidant capacity of the fractions was verified by sequestration of the free radical 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid (ABTS) and iron chelating activity. The antimicrobial activity was determined using the microdilution method and the modulating activity was determined using sub-inhibitory concentrations of the fractions in association with antibiotics., Results: The chemical analyzes revealed the presence of catechin, caffeic acid, rutin, orientin, quercetin, apigenin, luteolin and kaempferol, where all are present in the ethyl acetate fraction. The fractions exhibited moderate antioxidant and antimicrobial activities against Gram-positive and Candida strains in addition to modulating the activity of conventional antibiotics. The most expressive result was obtained from the association of the chloroform fraction with cefotaxime, which produced a synergistic effect, reducing the minimum inhibitory concentration (MIC) of the antibiotic from 1,024 to 256 μg/mL., Discussion: The fractions presented a constitution rich in phenolic compounds, especially flavonoids. The data obtained demonstrated that the fractions presented moderate antioxidant activity by acting both as primary and secondary antioxidants. The fractions presented antimicrobial and antibiotic potentiating activities, being the first record of modulating effect of fractions of this species against the studied microbial strains, but failed in modulating the activity of antifungal drugs, indicating that this plant has the potential to be used in the development of therapeutic alternatives against resistant bacteria. The constitution phenolic the fractions may be responsible for their pharmacological properties in vitro., Competing Interests: The authors declare there are no competing interests.

Tropidurus hispidus has been used in traditional medicine in several regions of Northeastern Region of Brazil. Its medicinal use involves the treatment of diseases such as warts, sore throat, tonsillitis, chicken pox, varicella, measles, asthma, alcoholism, and dermatomycosis. The present study evaluated the topical anti-inflammatory activity of Tropidurus hispidus fat in treating ear edema in an animal model. Oil from T. hispidus (OTH) was evaluated on its effect against experimental inflammation in mice. OTH was extracted from body fat located in the ventral region of Tropidurus hispidus using hexane as a solvent. We used the model of mouse ear edema induced by phlogistic agents, croton oil (single and multiple applications), arachidonic acid, phenol, capsaicin, and histamine, applied into the right ears of animals pretreated with acetone (control), dexamethasone, or OTH. OTH inhibited the dermatitis induced by all noxious agents, except capsaicin. This effect may be related to the fatty acids present in OTH.

Ursolic acid, an important bioactive compound, was isolated from ethanol extract of aerial parts of Sambucus australis. In order to develop bioactive ursolic acid derivatives, two semi-synthetic compounds were obtained through modification at C-3. The antibacterial activity of the ursolic acid and its derivatives was investigated. The microdilution method was used for determination of the minimal inhibitory concentration (MIC), against twelve bacterial strains. The influence of ursolic acid and its derivatives on the susceptibility of some bacterial pathogens to the aminoglycosides antibiotics neomycin, amikacin, kanamycin and gentamicin was evaluated. The most representative synergistic effect was observed by 3β-formyloxy-urs-12-en-28-oic acid at the concentration of 64 μg/mL in combination with kanamycin against Escherichia coli (27), a multidrug-resistant clinical isolate from sputum, with reduction of MIC value from 128 μg/mL to 8 μg/mL. Ursolic acid and its derivatives were examined for their radical scavenger activity using the DPPH assay, and showed significant activity.

Momordica charantia L. belongs to the family Curcubitaceae and it is very common in many Brazilian regions. The plant is a liana with flowers and yellow fruits that present red seeds when are ripe. Popularly known as "melão-de-sãocaetano", "melão amargo" or "cabaço-amargo", it possesses many uses: antidiabetic, antihelmintic, antmicrobial, anticancerigenous and antioxidant. The phytochemical prospection of the fresh and dried leaves extracts showed the presence of different classes of secondary metabolites, as flavonoids, alkaloids and tannins, that have demonstrated antimicrobial action. Fresh and dried leaves presented significantly antimicrobial activity against all bacterial strains tested, specially Escherichia coli. Ethyl acetate fractions were effective against Escherichia coli and Bacillus cereus. The modulatory activity was significative too.