Resumo em Inglês:

ABSTRACT The Brazilian Savanna biome has the largest plant diversity among savannas worldwide and is the predominant biome in Goiás state, Brazil. Among plant species previously catalogued in the Brazilian Savanna, the Myrtaceae family has received attention, as these plants show great economic potential for its medicinal properties, food and ecological importance, highlighting in this context the Psidium genus. In order to contribute to the differentiation of problematic taxonomic groups, such as Myrtaceae, and to quality control of its plant material, morphological and venation leaf studies of four species of Psidium were performed. For this purpose, leaf samples of Psidium firmum O.Berg., P. myrsinites DC., P. laruotteanum Cambes., and P. guineense Sw. were collected from Goiás State University, Anápolis Air Base, and Serra de Caldas Novas State Park and submitted to classical techniques for morphological and leaf venation characterizations. The results showed that P. firmum presents brochidodromous secondary veins, marginal last venation of the fimbrial type, an abaxial surface with a grooved midrib, flat secondary veins on both sides, an apex obtuse to mucronate, and a rounded base. P. guineense presents trichomes on both surfaces, a grooved midrib on the adaxial surface and a prominent midrib on the abaxial surface, which distinguishes this species from all other Myrtaceae species examined in the present study. The species P. guineense and P. firmum presented a set of differential leaf characteristics among the others taxa of the genus, clearly separating these plants in the morphological identification key.

Resumo em Inglês:

ABSTRACT One oil sample isolated from leaves of Artabotrys jollyanus Pierre, Annonaceae, from Côte d’Ivoire has been analyzed by GC(RI), GC-MS and 13C NMR. In total, thirty-seven compounds accounting for 96.9% of the relative composition have been identified. The composition of the essential oil was dominated by trans-calamenene (15.7%), α-copaene (14.8%), α-cubebene (10.4%), cadina-3,5-diene (10.3%), (E)-β-caryophyllene (6.3%) and cadina-1,4-diene (6.1%). 13C NMR spectroscopy was very useful in the identification of trans-calamenene, 7-hydroxycalamenene, cadina-3,5-diene and cadina-1,4-diene. Moreover, monitoring the evolution of the leaf essential oil composition and the yield on a 12-month period (one sample per month) was achieved. The twelve essential oil samples exhibited a chemical homogeneity but the yield varied from sample to sample (0.26–0.60%).

Resumo em Inglês:

ABSTRACT Trembleya phlogiformis DC., Melastomataceae, is a shrub whose leaves are used as a dye for dyeing wool and cotton. The present article aimed to carry out the morphological description of the species, to study the chemical composition of volatile oils from the leaves and flowers and the seasonal variability from the leaves during a year. Macroscopic characterization was carried out with the naked eye and with a stereoscopic microscope. Volatile oils were isolated by hydrodistillation in Clevenger apparatus and analyzed by gas chromatography/mass spectrometry. The major components of the volatile oil of T. phlogiformis flowers were: n-heneicosane (33.5%), phytol (12.3%), n-tricosane (8.4%) and linoleic acid (6.1%). It was verified the existence of a large chemical variability of the volatile oils from the leaves of T. phlogiformis over the months, with the majority compound (oleic alcohol, ranging from 5.7 to 26.8%) present in all samples. A combination of Cluster Analysis and Principal Component Analysis showed the existence of three main clusters, probably related to the seasons. The results suggested that the volatile oils of T. phlogiformis leaves possess high chemical variability, probably related to variation associated with rainfall and the variation in the behavior of specimens throughout the year. This research provides insights for future studies on the volatile oils obtained from the T. phlogiformis leaves and flowers, mainly related to biological markers of applications monitored in the leaves and flowers of this species.

Resumo em Inglês:

ABSTRACT The phenolic content of the medicinal species Connarus perrottetti var. angustifolius Radlk., Connaraceae, Cecropia obtuse Trécul, Cecropia palmata Willd., Urticaceae; and Mansoa alliacea (Lam.) A.H.Gentry, Bignoniaceae, collected in three different years was evaluated. Plant infusions and hydroalcoholic, butanol and ethyl acetate extracts were analyzed by high-performance liquid chromatography with diode array detection. In order to endorse these results, analysis by electrospray mass spectrometry was also performed. Were identified: gallic acid, catechin, caffeic acid, ferulic acid, rutin, quercitrin and resveratrol. C. perrottetti showed greater diversity of polyphenols. M. alliacea had the higher concentration of caffeic acid even though it was found in all species. Catechin was the major antioxidant, but was not detected in M. alliacea. However, we discuss the popular use of these species, as well as their phenolic constitution and the interannual distribution of phenolic compounds.

Resumo em Inglês:

ABSTRACT High performance liquid chromatography profiling with mass spectrometry detection was applicable to identify known and novel multidrug-resistance glycolipid inhibitors from the complex resin glycosides mixture of Ipomoea alba L., Convolvulaceae, seeds. Albinosides X and XI were purified by recycling liquid chromatography and their structural elucidation was accomplished by nuclear magnetic resonance. Albinoside XI exerted a strong potentiation of vinblastine susceptibility in multidrug-resistant human breast carcinoma cells.

Resumo em Inglês:

ABSTRACT This paper reports the first study of the variation of the chemical composition and abundance of the essential oil of Croton heliotropiifolius, in four seasons, and the evaluation of its antibacterial activity. Essential oil obtained from leaves of C. heliotropiifolius were analyzed by GC/MS and evaluated against eight bacteria strains by broth microdilution method. The chemical constituents identified were the same in all samples, but with different proportions. The total percentages identified were 96.58% in summer, 92.08% in autumn, 98.44% in winter and 90.78% in spring. The majors constituents are β-caryophyllene, bicyclogermacrene, germacrene-D, limonene and 1,8-cineole. β-Caryophyllene was the major compound in all samples. The results of the antibacterial evaluations showed weak to moderate activity against the analyzed strains. In all analyzes was observed that essential oil sample collected in summer stands out from the others, displaying stronger activity against Gram-positive as Gram-negative bacteria.

Resumo em Inglês:

ABSTRACT Schinus terebinthifolius Raddi, Anacardiaceae, native to Brazil, is referred to as "pimento-rosa" and is used to treat inflammatory disease in folk medicine. Studies have reported important pharmacological properties, but these effects have still not been fully exploited. This study reports that the crude extract and isolated compounds of S. terebinthifolius (leaves) have in vitro antioxidant, antiproliferative, and in vivo anti-inflammatory activities. The samples were evaluated for antioxidant activity using 2, 2-diphenyl-1-picrylhydrazyl, β-carotene/linoleic acid and 2,2′-azino-bis-(3-ethylbenzothiazoline)-6-sulphonic acid reagents. The anti-inflammatory effects were assayed against a carrageenan-induced paw oedema model in mice to test doses of 10, 100 and 300 mg/kg at different time points in addition to myeloperoxidase activity analysis. The antiproliferative activity was evaluated using ten human tumour cell lines. Two derivatives of gallic acid and four flavonoids were isolated and exhibited considerable antioxidant activity. The extract and its compounds showed selectivity towards ovarian cancer cells, with growth inhibitory activity values ranging from 1.9 to 6.5 µg/ml. Sample extracts and methyl gallate significantly inhibited carrageenan-induced oedema in the mice paw oedema experimental model. The calculated topological polar surface area for methyl gallate (86.98 Å2) showed good intestinal absorption. The effects reported herein are be related to the presence of flavonoids and the galloyl phenolic derivative content.

Resumo em Inglês:

ABSTRACT Pilosocereus pachycladus F. Ritter, Cactaceae, popularly known as "facheiro", is used as food and traditional medicine in Brazilian caatinga ecoregion. The plant is used to treat prostate inflammation and urinary infection. The present work reports the first secondary metabolites isolated from P. pachycladus. Therefore, the isolated compound 4-hydroxy-3,5-dimethoxy benzaldehyde (syringaldehyde) was evaluated as modulator of Staphylococcus aureus pump efflux-mediated antibiotic resistance. The isolation of compounds was performed using chromatographic techniques and the structural elucidation was carried out by spectroscopic methods. In order to evaluate syringaldehyde ability to modulate S. aureus antibiotic resistance, its minimum inhibitory concentrations (µg/ml) was first determinate, then, the tested antibiotics minimum inhibitory concentrations were determined in the presence of the syringaldehyde in a sub-inhibitory concentration. The chromatographic procedures led to isolation of twelve compounds from P. pachycladus including fatty acids, steroids, chlorophyll derivatives, phenolics and a lignan. The syringaldehyde did not show any antibacterial activity at 256 µg/ml against S. aureus. On the other hand the compound was able to reduce the antibiotic concentration (tetracycline, norfloxacin, ethidium bromide) required to inhibit the growth of drug-resistant bacteria, showing the ability of syringaldehyde of inhibiting the efflux pump on these bacteria.

Resumo em Inglês:

ABSTRACT Eugenia brasiliensis Lam., Myrtaceae, is used in folk medicine for anti-inflammatory diseases such as arthritis and rheumatism. This study investigated the anti-inflammatory activity and phenolic profile of the crude hydroalcoholic extract and ethyl acetate fraction from E. brasiliensis leaves. Crude hydroalcoholic extract and the ethyl acetate fraction were analyzed by HPLC-ESI-MS/MS in comparison to standard phenolic compounds. The anti-inflammatory activity of the crude hydroalcoholic extract (1, 10 and 25 mg kg-1) and the ethyl acetate fraction (10, 25 and 50 mg kg-1) was evaluated in a swiss mouse model of acute pleurisy induced by carrageenan, being the total cell count, exudation and analysis of nitrite/nitrate the inflammation parameters. HPLC-ESI-MS/MS analysis revealed apigenin, catechin, galangin, isoquercetin, myricetin, quercetin and rutin. Crude hydroalcoholic extract and ethyl acetate fraction were effective in inhibiting cell migration in all tested doses. Crude hydroalcoholic extract was effective in inhibiting exudation only at the 10 mg kg-1 dose; ethyl acetate fraction was effective in all tested doses. Results for nitrite/nitrate levels reveals that only the ethyl acetate fraction was effective at the tested doses. This is the first report of the presence of isoquercetin, galangin and apigenin in this species. Results from the phytochemical analysis enhance the chemical knowledge of this species. In the future, together with more studies, validation of its popular use in inflammatory diseases is possible.

Resumo em Inglês:

ABSTRACT Hyptis marrubioides Epling, Lamiaceae, a species from Brazilian Cerrado, has been used against gastrointestinal infections, skin infections, pain, and cramps. Herein, H. marrubioides seedlings were cultured in vitro under different wavelengths (white, blue, green, red, and yellow) with 50 µmol m-2 s-1 irradiance and a 16-h photoperiod. After 20 and 30 days of cultivation, shoot length, leaf number, fresh mass, and dry mass were evaluated. The flavonoid rutin content was determined by the HPLC-DAD method. The shoots were longer in plants cultivated under yellow (16.603 ± 0.790 cm, 1.8-fold), red (15.465 ± 0.461 cm, 1.7-fold), and green (14.677 ± 0.737 cm, 1.6-fold) lights than in control plants exposed to white light (9.203 ± 0.388 cm). The number of leaves increased in plants exposed to red (23.425 ± 1.138, 1.1-fold) and green (22.725 ± 1.814, 1.1-fold) lights, compared to control plants (20.133 ± 0.827). Fresh (0.665 ± 0.048 g, 1.2-fold) and dry (0.066 ± 0.005 g, 1.3-fold) mass of seedlings were the highest in seedlings grown under red light, compared to seedlings grown under white light (0.553 ± 0.048 and 0.028 ± 0.004, respectively). However, rutin production was higher under white (0.308 mg g-1 of dry weight) and blue lights (0.298 mg g-1 of dry weight). Thus, red light induces plant growth and increases leaf number and dry weight in in vitro-cultivated H. marrubioides, whereas blue and white lights promote the greatest rutin accumulation.

Resumo em Inglês:

ABSTRACT The phytochemical study of the extract leaves from Maytenus distichophylla Mart. and Salacia crassifolia (Mart. ex Schult.) G. Don, Celastraceae, resulted in the isolation of 3-oxofriedelane, 3β-hydroxyfriedelane, 3β,24-dihydroxyfriedelane, 3-oxo-28,29-dihydroxyfriedelane, two mixtures of pentacyclic triterpenes (α-amyrin with β-amyrin and 3β-stearyloxy-urs-12-ene with 3β-stearyloxy-olean-12-ene), 3β-palmityloxy-urs-12-ene, the steroid β-sitosterol and its glycosylated derivative β-glucosyl-β-sitosterol, tritriacontanoic acid and the natural polymer gutta percha. The chemical structures of these constituents were established by IR, 1H and 13C NMR spectral data. Crude extracts, the mixtures of triterpenes and the isolated constituents were subjected to in vitro acetylcholinesterase inhibitory evaluation. Acetylcholinesterase inhibitory effect was observed for crude chloroform extract leaves from M. distichophylla (100%) and S. crassifolia (97.93 ± 5.63%) and for the triterpenes 3β,24-dihydroxyfriedelane (99.05 ± 1.12%), 3-oxo-28,29-dihydroxyfriedelane (90.59 ± 3.76%) and 3β-palmityloxy-urs-12-ene (97.93 ± 1.47%). The percent inhibitions induced by these natural products were very similar to those produced by physostigmine (93.94 ± 2.10%) a standard acetylcholinesterase inhibitor. Therefore, these results open perspectives for the use of these species as source of compounds with similar physostigmine pharmacological effect.

Resumo em Inglês:

ABSTRACT Salvia lachnocalyx Hedge, Lamiaceae, is an endemic sage which grows naturally in the Fars Province of Iran. The phytochemical analyses of the roots of S. lachnocalyx led to the isolation of five known diterpenoids: ferruginol (1), taxodione (2), sahandinone (3), 4-dehydrosalvilimbinol (4) and labda-7,14-dien-13-ol (5). Their chemical structures were elucidated using one (1H and 13C) and two dimensional (COSY, HSQC and HMBC) NMR spectroscopic data as well as electron impact mass spectra. The cytotoxicity of the purified compounds was evaluated against three human cancer cell lines; MOLT-4 (acute lymphoblastic leukemia), HT-29 (colorectal adenocarcinoma) and MCF7 (breast adenocarcinoma) and all of the isolated compounds showed considerable cytotoxic activity against these cell lines. Compounds 2 and 3 (IC50 range: 0.41–3.87 µg/ml) with endocyclic α,β-unsaturated carbonyl functional group, exhibited the highest cytotoxic activities compared to the other compounds (IC50 range: 6.85–17.23 µg/ml). In conclusion, compounds 2 and 3 are presented as compounds that deserve further investigation of their biological activities.

Resumo em Inglês:

ABSTRACT A methanol extract from the whole plant of Dendrobium formosum Roxb. ex Lindl., Orchidaceae, showed inhibitory potential against α-glucosidase and pancreatic lipase enzymes. Chromatographic separation of the extract resulted in the isolation of twelve phenolic compounds. The structures of these compounds were determined through analysis of NMR and HR-ESI-MS data. All of the isolates were evaluated for their α-glucosidase and pancreatic lipase inhibitory activities, as well as glucose uptake stimulatory effect. Among the isolates, 5-methoxy-7-hydroxy-9,10-dihydro-1,4-phenanthrenequinone (12) showed the highest α-glucosidase and pancreatic lipase inhibitory effects with an IC50 values of 126.88 ± 0.66 µM and 69.45 ± 10.14 µM, respectively. An enzyme kinetics study was conducted by the Lineweaver-Burk plot method. The kinetics studies revealed that compound 12 was a non-competitive inhibitor of α-glucosidase and pancreatic lipase enzymes. Moreover, lusianthridin at 1 and 10 µg/ml and moscatilin at 100 µg/ml showed glucose uptake stimulatory effect without toxicity on L6 myotubes. This study is the first report on the phytochemical constituents and anti-diabetic and anti-obesity activities of D. formosum.

Resumo em Inglês:

ABSTRACT Citrus is an economically important fruit for Egypt, but its peel also is one of the major sources of agricultural waste. Due to its fermentation, this waste causes many economic and environmental problems. Therefore it is worthwhile to investigate ways to make use of this citrus waste generated by the juice industry. This study was aimed to explore the hypocholesterolemic, antidiabetic activities of four varieties of citrus peels agrowastes, to isolate the main flavonoids in the active fractions and to quantify them by HPLC method for nutraceutical purposes. All the tested samples of the agro-waste Citrus fruits peels showed significant decrease in cholesterol, triacylglyceride and glucose. The most decrease in cholesterol level was observed by mandarin peels aqueous homogenate and its hexane fraction (59.3% and 56.8%, respectively) reaching the same effect as the reference drug used (54.7%). Mostly, all samples decrease triacylglyceride (by 36%–80.6%) better than the reference drug used (by 35%), while, glucose was decreased (by 71.1%–82.8 and 68.6%–79.6%, respectively) mostly by the aqueous homogenates (except lime) and alcoholic extracts (except mandarin) of Citrus fruits peels better than the reference drug used (by 68.3%). All the isolated pectin, from the four cultivars, has significant effect on the three parameters. The comparative HPLC rapid quantification of nobiletin in the different by-product citrus varieties hexane fractions revealed that nobiletin is present in higher concentration in mandarin (10.14%) than the other species. Nobiletin and 4′,5,7,8-tetramethoxy flavone were isolated from mandarin peels hexane fraction by chromatographic fractionation. This is the first report of the comparative HPLC quantification of nobiletin and biological studies of different citrus peels species as agro-waste products. Based on these results, we suggest the possibility that Citrus fruits peels may be considered as an antidiabetic and hypocholesterolemic nutraceutical product.

Resumo em Inglês:

ABSTRACT The present study aimed to investigate the anti-inflammatory activity of ethanolic extract from Casearia sylvestris Sw., Salicaceae, leaves and to identify the compounds responsible for this activity. The ethanolic extract from C. sylvestris leaves was fractionated by solid phase extraction and the chemical composition of extract and fractions were assessed by chromatographic techniques. Casearin-like clerodane diterpenes were quantified in ethanolic extract (27.4%, w/w) and in fraction 2 of solid phase extraction (50.6%, w/w). Carrageenan-induced paw edema and carrageenan-induced pleurisy assays (rats) were used to evaluate anti-inflammatory activity of ethanolic extract, its fractions and clerodane diterpenes from C. sylvestris – caseargrewiin F and casearin B. The ethanolic extract was tested in the rat paw edema model and the doses tested (10 and 100 mg/kg) had no effect. In the pleurisy model, the extract doses of 300 and 500 mg/kg showed inhibitory effect. The fraction 2 of solid phase extraction (10 mg/kg), caseargrewiin F and casearin B (0.5 mg/kg) showed a significant reduction (p < 0.05) of the carrageenan-induced paw edema in rats compared to indomethacin. Gastric ulcers were not observed in animals treated with samples from C. sylvestris. In conclusion, the ethanolic extract from C. sylvestris, its enriched fraction of clerodane diterpenes, casearin B and caseargrewiin F exhibited anti-inflammatory activity on in vivo models in rats. Casearin-like clerodane diterpenes may be considered active chemical markers for C. sylvestris leaves. On the other hand, these diterpenes are promising compounds in the development of new drugs with anti-inflammatory action without gastric side effects.

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ABSTRACT Pharmacological activities as anti-inflammatory, anti-hyperuricemic, anti-gouty arthritis, antitumor and trypanocidal activities of the aerial parts from Lychnophora trichocarpha (Spreng.) Spreng. ex Sch.Bip., Asteraceae (Brazilian arnica) have already been proved. Eremantholide C is a sesquiterpene lactone and one of the active chemical constituents responsible for these activities presented by L. trichocarpha. Therefore, the aim of this work was to develop and validate a stability indicating HPLC method for eremantholide C. Eremantholide C stability was evaluated in L. trichocarpha ethanolic extract and in its isolated form. Analytical conditions employed C18 column, acetonitrile/water in gradient elution, flow of 0.8 ml/min at 30 ºC. To correct for the loss of analyte during sample preparation the use of coumarin as an internal standard was necessary. The developed method provides good separation and resolution of the peaks, allowing quantification of eremantholide C, isolated or directly in the ethanolic extract, in internal standard presence. Validation results showed that this method is linear in the concentration range 2–180 µg/ml, precise, accurate and specific. Stability studies showed that L. trichocarpha ethanolic extract and eremantholide C remain stable for 6 months when stored at room temperature and impermeable glass bottle, therefore they can be used safely and effectively within this period. While at 40 ºC there was stability loss, at 8 ºC a stability increase was observed for the extract and the isolated eremantholide C. Forced degradation studies showed that eremantholide C degraded under acidic and alkaline conditions and was stable for three days under neutral and oxidative conditions, and when exposed to high temperature. Thus, with the development of a stability indicative method and the application of it in eremantholide C stability studies, the results can guide the development of new products that adequately preserve the original features of the biologically active substance with quality, safety and efficacy.

Resumo em Inglês:

ABSTRACT Stevia rebaudiana (Bertoni) Bertoni, Asteraceae, leaf extract has recently called the attention of food industry as a proposal for natural sweetener. The sweet flavor is attributed to the glycosides, in especial stevioside and rebaudioside A, which are the plant main chemical markers. The aim of the work reported here was to optimize the turbo-extraction of stevia leaves using water, ethanol 70% and 90% (w/w) as green solvents. A 25-2 factorial design was applied to study the linear effects of the drug size, solvent to drug ratio, temperature, time and also the turbolysis speed on the extraction of glycosides. The glycosides exhaustive extraction showed that ethanol 70% gave better results and was used for turbo-extraction. The stevioside and rebaudioside A contents were quantified by a validated method by high performance liquid chromatographic with photodiode array detector. The contents of stevioside and rebaudioside A in fluid extract increased with the drug size, but decreased at high shearing speeds and solvent to drug ratio, while their yields decreased at higher temperature and were not affected by turbo speed. An increase in solvent to drug ratio reduced significantly the glycosides percent in dried extract. Optimal solution for S. rebaudiana leaves turbo-extraction was determined by desirability functions. The optimal extraction condition corresponded to drug size of 780 µm, solvent to drug ratio of 10, extraction time of 18 min; temperature of 23 ºC and turbo speed of 20,000 rpm, resulting in yields of 4.98% and 2.70%, for stevioside and rebaudioside A, respectively. These yields are comparable to the ones recently published for dynamic maceration, but with the advantage of shorter extraction times. This work demonstrates that turbolysis is promising for S. rebaudiana glycosides extraction and stimulate new research on the purification of these extracts, which may become an interesting source of income for developing countries such as India and Brazil.

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ABSTRACT Obtaining artemisinin and its derivatives is very costly, which limits access to low-income people. Some hydroalcoholic extract of Artemisia annua L., Asteraceae, which has shown comparable antimalarial activity could be an alternative to the purified compound, especially if the cultivars have higher content of artemisinin. The objective of this study was to evaluate the effects of the extraction parameters (ethanol graduation, previous shaking time in an ultrasound bath and drug/solvent ratio) on the yield of artemisinin in the liquid extract obtained by percolation from A. annua and then optimize the extraction efficiency of this compound. The Box–Behnken (33) factorial design was used in association with response surface methodology. The derivatization reaction of artemisinin was used in an analytical method which was submitted to validation, after reaching the specification of the selectivity, linearity, precision, accuracy and robustness. Detection and quantification limits were 1.3 and 4.0 µg/ml, respectively. The largest amount of this compound of interest was obtained without any ultrasound bath, with an ethanol graduation of 95% and a drug/solvent ratio of 2%. Drug/solvent ratio was the factor which most influenced extraction efficiency. The maximum range of artemisinin yield was 1.21%. Information obtained in this study can be used for future approaches to determining and extracting artemisinin from A. annua.

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ABSTRACT This work describes the establishment of procedures to induce in vitro callogenesis from Poincianella pyramidalis (Tul.) L. P. Queiroz, Fabaceae, explants. Nodal, internodal and leaf segments were isolated from in vitro germinated seedlings and cultured in MS medium with 0, 2.5, 5 and 10 mg l-1 of 2,4-dichlorophenoxyacetic acid. After 30 days, the explants with induced callus showed a quadratic response for the segments nodal, internodal and leaf, with increasing the callus formation in 2,4-dichlorophenoxyacetic acid concentrations of 6.28, 6.49 and 4.91 mg l-1, respectively. In 30 days there was a linear oxidation rise with the increase to the 2,4-dichlorophenoxyacetic acid. After 60 days, oxidation values were minimum, at 2,4-dichlorophenoxyacetic acid concentrations of 5.13 mg l-1 (internodal) and 3.98 mg l-1 (leaf). The highest callus production was observed after 30 days in the presence of 6.09 mg l-1, 5.82 mg l-1 and 4.91 mg l-1 of 2,4-dichlorophenoxyacetic acid in nodal, internodal and leaf segments, respectively. After 60 days these segments showed peaks of production at 7.0 mg l-1 (nodal), 6.15 mg l-1 (internodal) and 5.08 mg l-1 (leaf) of 2,4-dichlorophenoxyacetic acid. For callus induction the intake of 2,4-dichlorophenoxyacetic acid was essential. The greater intensity in callus formation was observed in 4.91 mg l-1 in leaf segments after 30 days.

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ABSTRACT Aspergillus spp. cause economic impacts due to aflatoxins production. Although the toxicity of aflatoxins is already known, little information about their ecological roles is available. Here we investigated the compounds produced by Aspergillus nomius ASR3 directly from a dead leaf-cutter queen ant Atta sexdens rubropilosa and the fungal axenic culture. Chemical analyses were carried out by high-resolution mass spectrometry and tandem mass spectrometry techniques. Aflatoxins B1 and G1 were detected in both the axenic culture and in the dead leaf-cutter queen ant. The presence of these mycotoxins in the dead leaf-cutter queen ant suggests that these compounds can be related to the insect pathogenicity of A. nomius against A. sexdens rubropilosa.

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ABSTRACT Uses of medicinal plants by people around the world significantly contribute and guide biologically active compounds research that can be useful in the combat against various diseases. Due to a great chemical and structural variety found in their vegetal structures it consolidates ethnopharmacology as an important science for the pharmaceutical section. Inserted in the diversity of medicinal plants, is the Maytenus genus, whose research has already revealed lots of isolated substances which are responsible for a great variety of biological activities, among which we cite analgesic and anti-inflammatory, for the treatment of inflammatory diseases such as rheumatoid arthritis, gastritis, ulcers and gastrointestinal disorders. The aim of this review article is to make a compendium of the Maytenus genus and its isolated chemical compounds, among them tingenone. The elucidation of its mechanism of action reveals promising sources for the development of new drugs specially targeted for the treatment of painful inflammatory diseases.