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This work is the first to describe the modulation of antibiotic activity of the bryophyte Octoblepharum albidum Hedw extract. The antibacterial activity of ethanolic extract of O. albidum (EEOa), alone and in association with aminoglycosides, was determined against six bacterial strains by a microdilution test. The results showed a similar inhibitory activity of EEOa against Escherichia coli ATCC 25922 and Klebsiella pneumoniae ATCC 33018 (MICs 512 μg/mL). The synergistic effect of the extracts and aminoglycosides was also verified. The most pronounced effects were obtained with EEOa + gentamicin against E. coli and EEOa + kanamycin against K. pneumoniae with MICs reduction (128 to 32 μg/mL). The data from this study are indicative of the antibacterial activity of the bryophyte O. albidum extracts and its potential in modifying the resistance of aminoglycosides analyzed.

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. [ABSTRACT FROM AUTHOR]

Background: Cordia verbenacea is a Brazilian coastal shrub popularly known as "erva baleeira". The essential oil from fresh leaves was obtained by hydrodistillation and analyzed by CG/MS. The main components were identified as β-caryophyllene (25.4%), bicyclogermacrene (11.3%), δ-cadinene (9.%) and α-pinene (9.5%). In this study, the antimicrobial activity of Cordia verbenacea was evaluated. Materials and Methods: The minimal inhibitory concentration (MIC) of the essential oil was obtained using the broth microdilution assay (from 512 to 8 μg/ml). Results: The results showed that the essential oil presented fungistatic activity against Candida albicans and Candida krusei and antibacterial activity against Gram-positive strains (Staphylococcus aureus and Bacillus cereus) and against multiresistant Gram-negative (Escherichia coli 27), in all tests the MIC was 64 μg/ml. When the essential oil was associated to aminoglycosides (subinhibitory concentrations, MIC/8), a synergic and antagonic activity was verified. The synergic effect was observed to the amikacin association (MIC reduction from 256 mlto 64 μg/ml) in all strains tested. Conclusion: The essential oil of Cordia verbenacea influences the activity of antibiotics and may be used as an adjuvant in antibiotic therapy against respiratory tract bacterial pathogens. [ABSTRACT FROM AUTHOR]

Background: The use and investigation of natural products with antimicrobial activity from vegeral source have been reported by several researchers. Cajanus cajan (Fabaceae) is a multiple use specie mainly as human food. In popular medicine, diverse parts of the plant are used as sedative and to treat cough, hepatitis, and diabetes. Materials and Methods: This study shows the characterization of secondary metabolites present in ehtanolic extracts from leaves and roots of Cajanus cajan by phytochemical prospection. The evaluation of the antifungal activity was performed by the microdilution method, and from the subinhibitory concentrations (MIC 1/8) the modulatory activity of antifungical (fluconazole and ketoconazole) was analyzed by the direct contact assay against C. albicans ATCC40006, Candida krusei ATCC 6538 and Candida tropicalis ATCC 40042. Results: The results showed the presence of tannins, flavonoids, and alkaloids in both extracts as the clinically relevant antifungal activity. The modulatory potential is presented by the antifungal tested against yeasts. Conclusion: The extracts studied here have demonstrated to be a new therapeutic source to treat these microorganism-associated diseases. [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 leaves of Lantana camara L. (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 25 identified components, bicyclogermacrene (26.1%), β-caryophyllene (24.4%), germacrene D (19.2%) and valecene (12.0%) were the main constituents. The essential oil volatile constituents inhibited the growth of Staphylococcus aureus and Pseudomonas aeruginosa with MIC of 1 and > 1 mg/L, respectively. The activity of the antibiotic amikacin was increased by 65% against S. aureus and P. aeruginosa after contact with the volatile components. [ABSTRACT FROM AUTHOR]

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]

Hepatoprotective activity of Croton zehntneri Pax & Hoffman (Euphorbiaceae) leaf essential oil (EOCz) was evaluated against single dose of acetaminophen-induced (500 mg/kg, p.o.) acute hepatotoxicity in mice. EOCz significantly protected the hepatotoxicity as evident from the activities of serum glutamate pyruvate transaminase (GPT), serum glutamate oxaloacetate transaminase (GOT) activities, that were significantly (p<0.01) elevated in the acetaminophen alone treated animals. Histopathological examinations of liver tissue corroborated well with the biochemical changes. Hepatic steatosis, hydropic degeneration and necrosis were observed in the acetaminophen treated group, while these were completely absent in the standard and EOCz treated groups. In conclusion, these data suggest that the Croton zehntneri essential oil can prevent hepatic injuries from acetaminophen-induced hepatotoxicity in mice. [ABSTRACT FROM AUTHOR]

Objective: In this work, we report the antibacterial and modulatory activity of Lantana montevidensis Briq., Materials and Methods: The antibacterial activities of leaf (LELm) and root (RELm) extracts alone or in association with aminoglycosides were determined by a microdilution test. Multiresistant strains of Escherichia coli (Ec 27) and Staphylococcus aureus (Sa 358) were used., Results: The results show the inhibitory activity of LELm against E. coli (minimal inhibitory concentration [MIC] 16 μg/mL) and S. aureus (MIC 128 μg/mL). The synergistic effect of the extracts and aminoglycosides was verified too. The maximum effects were obtained with RELm with gentamicin against E. coli with MIC reduction (312 to 2 μL)., Conclusion: The data from this study are indicative of the activity antibacterial of extracts of L. montevidensis and its potential in modifying the resistance of aminoglycosides.

The study examined the antiinflammatory and antinociceptive effects of the sesquiterpene (-)-α-bisabolol (BISA). The antiinflammatory effect was evaluated on acute models of dermatitis induced by Croton oil, arachidonic acid, phenol and capsaicin, respectively, in mouse ear. BISA inhibited the dermatitis induced by all noxious agents, except capsaicin. BISA was assessed in two established mouse models of visceral nociception. Mice were pretreated orally with BISA, and the pain-related behavioral responses to intraperitoneal cyclophosphamide or to intracolonic mustard oil were analyzed. BISA showed a dose-unrelated significant antinociception. Collectively, the results suggest that BISA may be an topical antiinflammatory and visceral antinociceptive agent., (Copyright © 2010 Elsevier B.V. All rights reserved.)

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.