Polycyclic aromatic hydrocarbons (PAHs) are an important environmental issue and the identification of new biocatalysts for an efficient biodegradation of these compounds is essential for bioremediation. Therefore, fungi strains isolated for the first time from a tropical peat at Santo Amaro das Brotas (Brazil) were studied for fluoranthene biodegradation. Fusarium sp. AC-7, Penicillium sp. AC-1 and Penicillium sp. AC-6 were isolated using fluoranthene as sole carbon source. All strains were tested for biodegradation of 100 mg L−1 fluoranthene during 14 and 28 days. After 28 days of biodegradation, 64 ± 3, 60 ± 4 and 51 ± 2% biodegradation was observed for Penicillium sp. AC-1, Penicillium sp. AC-6 and Fusarium sp. AC-7, respectively. Analysis of the obtained compounds enabled the identification of four metabolites, which were common to the three employed strains: anthrone, anthraquinone, 9-methoxyanthracene and cyclopropa[1]phenanthrene. It is important to note that control experiments were performed. The obtained results clearly demonstrated the efficiency of tropical peat fungi in the transformation of fluoranthene. These findings showed the potential of tropical peats for isolation of fungi and indicated that these strains can be applied for bioremediation processes of areas contaminated with fluoranthene and other PAHs.

Este trabalho descreve a síntese e caracterização de um novo adsorvente mesoporoso que consiste o MCM-41 funcionalizado com o ácido p-aminobenzóico modificado (PABA-Si). A síntese foi realizada pelo método hidrotermal/co-condensação. O PABA-MCM-41 foi caracterizado usando FTIR, SAXS, adsorção/desorção de N2, MEV e TG. Os experimentos em batelada foram utilizados para determinar os efeitos da concentração inicial do adsorbato, tempo de contato e temperatura. A adsorção do benzo[a]pireno (B[a]P) alcançou o equilíbrio depois de 90 min (q e = 27,2 µg g-1) e concentrações mais altas do adsorbato foram associadas com o aumento, em ambos, da percentagem de remoção (71,0-95,7%) e no valor de q e (20,1-27,1 µg g-1). A adsorção seguiu o modelo cinético de pseudo-segunda ordem, e se ajustou ao modelo de isoterma de Langmuir. Foi verificado em temperaturas mais altas um aumento na taxa inicial de adsorção e na constante cinética. Os parâmetros termodinâmicos indicaram que o processo foi espontâneo, endotérmico e com uma tendência para desordem.

This work describes the synthesis and characterization of a new mesoporous adsorbent consisting of MCM-41 functionalized with modified p-aminobenzoic acid (PABA-Si). The synthesis was performed by a hydrothermal/co-condensation method. The PABA-MCM-41 was characterized using FTIR, SAXS, N2 adsorption/desorption, SEM, and TG. Batch experiments were employed to determine the effects of initial adsorbate concentration, contact time, and temperature. The adsorption of benzo[a]pyrene (B[a]P) reached equilibrium after ca. 90 min (q e = 27.2 µg g-1), and higher adsorbate concentrations were associated with increases in both the percentage removal (71.0-95.7%) and the value of q e (20.1-27.1 µg g-1). The adsorption followed pseudo-second order kinetics, and was fitted using the Langmuir isotherm model. At higher temperatures, there were increases in the initial rate of adsorption and the kinetic constant. The thermodynamic parameters indicated that the process was spontaneous, endothermic, and with a tendency to disorder.

Erythrina velutina Willd., Fabaceae, is a medicinal plant that can be found in the tropics and subtropics, including in the semi-arid northeastern Brazil. It is commonly used in folk medicine to treat anxiety, agitation and insomnia. E. velutina has been known to present analgesic, anti-inflammatory and antibacterial activities, however, it is unknown if this plant present a protective effect on DNA. We assessed the antigenotoxic effect of E. velutina against the genotoxic effects induced by MMS in the root meristem cells of Allium cepa. Three concentrations of the aqueous extract (100, 200 and 400 mg/L) of this medicinal plant were used in three different types of treatment (pre-, post- and simultaneous). The effects of the extracts on the root meristem cells of A. cepa were analyzed at both macroscopic and microscopic levels. Protective effects were observed at higher concentrations in pre-treatment and in simultaneous treatment. The results suggest that E. velutina may present antigenotoxic properties and demonstrate its chemopreventive potential.

The effects of the decoction of Erythrina velutina Willd., Fabaceae, were investigated using the root meristem cells of Allium cepa L., Amaryllidaceae. Ten concentrations of the aqueous extract (0.125 to 1.25%) of this medicinal plant were analyzed at both macroscopic and microscopic levels. All concentrations showed root growth inhibition after 96 h treatment. Although there were no significant differences between the mitotic indexes of any concentration and the control, there were changes in the frequencies of cell stages at three different concentrations. Additionally, the presence of five different cells abnormalities was recorded: chromosome bridging, lagging chromosomes, chromosome fragments, disturbed metaphase and disturbed anaphase. These results suggest inhibitory and genotoxic activity of the decoction of E. velutina on Allium cepa.