Abstract Passiflora nitida Kunth, an Amazonian Passiflora species, is little studied, although the specie’s high biological potential. Herein the plant’s pharmacognostic characterization, extract production, antioxidant potential evaluation, and application of this extract in cosmetic products is reported. The physical chemical parameters analyzed were particle size by sieve analysis, loss through drying, extractive yield, total ash content, laser granulometry, specific surface area and pore diameter (SBET), differential scanning calorimetry, thermogravimetry (TG), and wave dispersive X-Ray fluorescence (WDXRF). Total phenol/flavonoid content, LC-MS/MS analysis, DPPH and ABTS antioxidant radical assays, cytotoxicity, melanin, and tyrosinase inhibition in melanocytes test provided evidence to determine the content of the major constituent. P. nitida dry extract provided a fine powder with mesopores determined by SBET, with the TG curve showing five stages of mass loss. The antioxidant potential ranged between 23.5-31.5 mg∙mL-1 and tyrosinase inhibition between 400-654 μg∙mL-1. The species presented an antimelanogenic effect and an inhibitory activity of cellular tyrosinase (26.6%) at 25 µg/mL. The LC-MS/MS analysis of the spray-dried extract displayed the main and minor phenolic compounds constituting this sample. The results indicate that P. nitida extract has promising features for the development of cosmetic formulations.

RESUMO A introdução de espécies exóticas é considerada uma das principais causas da perda de biodiversidade. A Floresta Nacional de Carajás é uma das maiores províncias minerais do mundo. As atividades da mineração provocaram alterações dos habitats naturais, deixando áreas degradadas após a exploração mineral. Uma das áreas de mineração dentro da FLONA de Carajás foi usada para a extração de ouro. No processo de exploração, uma enorme cava foi formada pela remoção do solo que foi colocado em montes nas proximidades. Para evitar a erosão do solo desses montes, uma gramínea exótica, Urochloa decumbens (Stapf) R.D.Webster (Poaceae) foi plantada. O objetivo deste estudo foi comparar o impacto desta gramínea não-nativa na riqueza de espécies e composição de espécies da regeneração natural nas áreas degradadas. Quatro áreas foram comparadas, duas com e duas sem a presença de U. decumbens. Em cada área, vinte e quatro parcelas de 1m² foram estabelecidas. A riqueza de espécies e os tamanhos das populações da regeneração natural foram significativamente menores nas parcelas onde a gramínea exótica estava presente. Nosso estudo mostra que U. decumbens tem um efeito negativo sobre a riqueza de espécies e densidade populacional e sua presença alterou a composição e distribuição de formas de vida da regeneração natural das espécies.

ABSTRACT The introduction of exotic species is considered as one of the major causes of biodiversity loss. The National Forest of Carajás is one of the largest mineral provinces in the world. Mining activities caused changes of the natural habitats, leaving degraded areas after the mineral exploitation. One of the mining areas within FLONA Carajás was used for the extraction of gold. In the process of exploitation, a huge depression was formed by the removal of soil which was mounded up nearby. To prevent soil erosion of these mounds, an exotic grass, Urochloa decumbens (Stapf) R.D.Webster (Poaceae) was planted. The objective of this study was to compare the impact of this non-native grass on species richness and species composition of the natural regeneration in the degraded areas. Four areas were compared, two with and two without presence of U. decumbens. In each area, twenty four 1m²/plots were established. Species richness of the regeneration areas and population sizes were significantly lower in the plots where the exotic grass was present. Our study shows that U. decumbens had a negative effect on species richness and population density, and its presence changed the species composition and distribution of life forms of the natural regeneration.

Os principais rios da bacia Amazônia e sua biota estão ameaçados pelos planos de construção de grandes usinas hidrelétricas que poderá causar fortes impactos nas comunidades vegetais das áreas alagadas. O objetivo desse estudo é apresentar os inventários botânicos em três áreas de vegetações inundadas dos rios Tocantins, Xingu e Tapajós no leste da Amazônia. Os resultados do estudo mostram uma flora altamente especializada das vegetações inundadas, claramente distintas entre as três bacias, embora os ambientes entre as bacias dos rios não sejam distintos entre si e as condições ambientais muito semelhantes. Somente 6 das 74 espécies ocorreram nos três inventários, sendo a maioria das arvores e arbustos restritos a um dos rios, indicando um alto grau de distribuição local. Espécies diferentes ocupam nichos ambientais semelhantes, mostrando alto valor de conservação dessas formações vegetais. Os planos de conservação devem considerar a complementaridade das espécies nas tomadas de decisões de onde colocar as unidades de conservação nesses nas florestas inundadas a fim de evitar de forma irreversível a perda da biodiversidade.

The major rivers of the Amazon River basin and their biota are threatened by the planned construction of large hydroelectric dams that are expected to have strong impacts on floodplain plant communities. The present study presents forest inventories from three floodplain sites colonized by alluvial riparian vegetation in the Tapajós, Xingu and Tocantins River basins in eastern Amazonian. Results indicate that tree species of the highly specialized alluvial riparian vegetation are clearly distinct among the three river basins, although they are not very distinct from each other and environmental constraints are very similar. With only 6 of 74 species occurring in all three inventories, most tree and shrub species are restricted to only one of the rivers, indicating a high degree of local distribution. Different species occupy similar environmental niches, making these fragile riparian formations highly valuable. Conservation plans must consider species complementarily when decisions are made on where to place floodplain forest conservation units to avoid the irreversible loss of unique alluvial riparian vegetation biodiversity.

OBJECTIVES: The aim of this study was to evaluate the influence of two adhesive systems and the post space region on the degree of conversion of dual resin cement and its bond strength to root dentin. MATERIAL AND METHODS: One three-step etch-and-rinse (All-bond 2, Bisco) and another one-step self-etch (Xeno III, Dentsply) adhesive systems were applied on 20 (n=10) crownless bovine incisors, at 12-mm-deep post space preparation, and a fiber post (FRC Postec, Ivoclar) was cemented using a dual cure resin cement (Duo-Link, Bisco). Three transverse sections (3 mm) were obtained, being one from each study region (cervical, middle and apical). The degree of conversion of the dual cure resin cement was determined by a micro-Raman spectrometer. The data (%) were submitted to repeated-measures analysis of variance and Tukey's test (p<0.05). RESULTS: For both groups, the degree of conversion means (%) (All bond 2cervical = 69.3; All bond 2middle = 55.1; All bond 2apical= 56; Xeno III cervical = 68.7; Xeno IIImiddle = 68.8; Xeno III apical = 54.3) were not significantly different along the post space regions (p<0.05). CONCLUSION: Neither the adhesive nor the post space region influenced the degree of conversion of the cement layer.