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The coal reserves in the south of Brazil were intensely exploited at the time of great demand for such fuel. This resulted in changes in the environment, mainly in the chemical, physical and biological characteristics of the soil. Due to the potential to control erosive processes, increase soil quality and restore biological diversity, revegetation is a promising alternative to recover those impacted areas. In that respect, bracatinga is a pioneering tree species that easily grow in different environments and has being planted as vegetation cover in areas under recovery. Therefore, the objective of this work was to characterize the chemical features and to evaluate the soil microbiological attributes in areas degraded by coal mining and under recovery using bracatinga as cover plant. In the bracatinga canopy projection area, soil samples were collected in the environmental restoration areas that have been, at the time of collecting, under a regime of 2, 4, 6 and 12 years of restoration. In addition an area with natural occurrence of bracatinga was used as control. Microbial biomass nitrogen, microbial biomass carbon and microbial biomass respiration increase in average 281, 230 and 157% respectively, when the 12-year-old areas were compared to the 2-year-old-areas. Likewise, a decrease in qCO2 in the order of 60% was observed for that same comparison. The 12-year-old areas reached the same values of qCO2 found in the reference area. The data suggest an improvement in the microbiological attributes of the soil with the increase in recovery time for the studied areas. SIGNIFICANCE AND IMPACT OF THE STUDY: In coal mining areas under recovery with typically acid soils, the use of the current recovery strategies (revegetation mainly) has been efficient to increase the quality of soils, especially in the environmental restoration areas. Soil microbiological attributes such as microbial biomass nitrogen, microbial biomass carbon, microbial basal respiration and metabolic quotient (qCO2 ) are dynamic and highly sensitive. These parameters have the potential to be adopted together with conventional attributes, such as floristic composition indices and species diversity indices, to evaluate the degree of any particular environmental recovery process being conducted at previously explored mining areas.

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In this study, we report the effects of arbuscular mycorrhizal fungi (AMF) and increasing doses of phosphorus (P) on the growth and production of secondary metabolites in Mimosa tenuiflora, a medicinal species native to Brazil. We used a completely randomized design with four inoculation treatments: Control not inoculated (1); Claroideoglomus etunicatum (2); Gigaspora albida (3); and C. etunicatum + G. albida (4) and four doses of P; P0 - baseline dose, P8, P16 and P32. After 70 d in a greenhouse, growth, mycorrhizal variables, biochemical and phytochemical parameters were evaluated. Compared to non-mycorrhizal plants, mycorrhized M. tenuiflora seedlings showed greater: growth, greater photosynthetic performance and content of soluble carbohydrates and secondary metabolites, with the most significant benefits occurring in soil with low to moderate P content (up to 16 mg kg-1). The plant growth is severely restricted at low P levels, but the addition of AMF appears to remove this limiting factor. Although M. tenuiflora responds to levels of phosphate fertilization, it responds well to mycorrhizal inoculation, especially with G. albida, which promotes benefits for the initial growth and secondary metabolite content in this plant species of medical and potential commercial interest and may be used instead of phosphate fertilizer.

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Mimosa tenuiflora (Mimosaceae) or jurema-preta is well distributed in the northeast Brazil, being popularly used to treat skin lesions, burns and inflammation. The healing effect of the alcoholic extract prepared with its barks corroborates the popular use. This study aimed to evaluate the inflammatory response of polysaccharides extracted from M. tenuiflora barks (EP-Mt) by methanol/NaOH and ethanol precipitation. Inflammatory activity was assessed in rat models of acute inflammation (paw edema and peritonitis), by the following parameters: edema, vascular permeability, leukocyte migration, myeloperoxidase activity and pharmacological modulation of nitric oxide and prostaglandins. EP-Mt presented 3.8% yield, 41% carbohydrate and 0.34% protein. EP-Mt (0.01, 0.1, 1.0 mg kg-1) injected by subcutaneous route elicited paw edema that lasted from 30-420 min, with maximal effect at 1 mg kg-1 (40x vs. saline), and was inhibited by L-NAME (52%) and dexamethasone (26%). EP-Mt (1 mg kg-1, via intraperitoneal) stimulated leukocytes migration (2.2x), mainly neutrophils (6.5x) and MPO activity (96%). The leukocyte migration elicited by EP-Mt was inhibited by dexamethasone (39%) and L-NAME (38%). EP-Mt containing high carbohydrate content induces acute inflammation via nitric oxide, which open perspectives of application in pathological conditions of immunosuppression.(AU)

Mimosa tenuiflora (Mimosaceae) ou "jurema-preta", amplamente distribuída no nordeste brasileiro, é utilizada popularmente no tratamento de lesões de pele, queimaduras e inflamação. O efeito cicatrizante do extrato alcoólico de suas cascas corrobora o uso popular. Avaliou-se o efeito inflamatório dos polissacarídeos da casca de M. tenuiflora (EP-Mt), obtidos por extração com metanol/NaOH e precipitação com etanol. O efeito inflamatório foi avaliado em modelos agudos em ratos (edema de pata, peritonite) por meio dos seguintes parâmetros: edema, permeabilidade vascular, migração leucocitária, atividade da mieloperoxidase e modulação farmacológica de prostaglandinas e óxido nítrico. EP-Mt apresentou 3,8% de rendimento, 41% de carboidratos totais e 0,34% de proteína. EP-Mt (0,01, 0,1, 1,0 mg kg-1), administrado por via subcutânea, induziu edema de pata com duração de 30 a 420 min e efeito máximo na dose de 1 mg kg-1 (40x vs. salina), o qual foi inibido por L-NAME (52%) e dexametasona (26%). EP-Mt (1 mg kg-1, via intraperitoneal) estimulou a migração de leucócitos (2,2x vs. salina), principalmente de neutrófilos (6,5x), com aumento da atividade da mieloperoxidase (96%). A migração de leucócitos foi inibida por dexametasona (39%) e L-NAME (38%). EP-Mt contendo elevado teor de carboidratos induz inflamação aguda via óxido nítrico com perspectivas de aplicação em condições patológicas(AU)

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Seismonastic or thigmonastic movements of Mimosa pudica L. is mostly because of the fast loss of water from swollen motor cells, resulting in temporary collapse of cells and quick curvature in the parts where these cells are located. Because of this, the plant has been much studied since the 18th century, leading us to think about the classical binomial stimulus-response (action-reaction) when compared to animals. Mechanic and electrical stimuli were used to investigate the analogy of mimosa branch with an artificial neuron model and to observe the action potential propagation through the mimosa branch. Boolean function applied to the mimosa branch in analogy with an artificial neuron model is one of the peculiarities of our hypothesis.

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A chemically sulfated galactomannan (BRS) from seeds of Mimosa scabrella had in vitro antiviral activity against Herpes simplex virus 1 (HSV-1), but not against Simian rotavirus A/SA11 (SiRV-A/SA11). It was examined by (13)C NMR spectroscopy, which showed the sulfate groups to be mainly at C-6 of galactose residues. BRS had a selective inhibition against HSV-1 during its attachment step, having an IC(50) lower than 2.5microg/ml, determined by plaque reduction, and a selectivity index of greater than 181, suggesting that the antiviral effect is likely due to interactions between the virus and BRS, being influenced its overall surface charge.

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The bark of the Mimosa tenuiflora (Willd.) Poiret (Leguminoseae) tree, known as tepescohuite in Mexico, is commonly used in this country and in Central America to elaborate different products for the treatment of skin burns and lesions. The cicatrizing properties of extracts obtained from this bark have been scientifically studied, attributing the main biological activity to its tannin and saponin content. Studies include clinical trials of phytodrugs based on Mimosae tenuiflora bark extracts for treatment of venous leg ulcerations. Recent commercialization of the plant drug Mimosae tenuiflorae cortex requires pharmacognostical information to develop quality-control methods for raw materials and extracts produced with this plant drug. The present paper reports a group of ethnobotanical, morphological, chemical, and molecular studies performed with Mimosae tenuiflora materials obtained by collection in the southeastern Mexican state of Chiapas. Macro- and micro-morphological parameters were established to authenticate the genuine drug that allowed detection of adulterants usually found in commercial samples of this plant material. These morphological characteristics can be used for rapid identification of the drug and are particularly useful in the case of powdered materials. The chemical studies performed demonstrated that tannins represent the major component group in the bark. Its content in genuine tepescohuite is 16% and is mainly composed of proanthocyanidins, a condition permitting a tannin-based chemical-control method for fingerprinting the plant drug. Contrariwise, the saponin concentration in Mimosae tenuiflora bark is extremely low, and its isolation and content evaluation represent a complex procedure that is unsuitable for routine control purposes. Finally, random amplified DNA (RAPD) analysis results a useful tool for obtaining DNA specific markers of Mimosae tenuiflora species which should be useful in future studies involving raw material authentication by molecular methods.

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