The preparation, characterization, theoretical calculations and biological application of four RuII complexes with 2-picolinate (pic), 2,2’-bipyridine (bipy) and P-P as ligands [P-P = 1,1-bis(diphenylphosphino)methane (dppm-1), 1,2-bis(diphenylphosphino)ethane (dppe-2), 1,3-bis(diphenylphosphino)propane (dppp-3) or 1,1’-bis(diphenylphosphino)ferrocene (dppf-4)], is here presented. The complexes 1-4, with general formula [Ru(pic)(P-P)(bipy)]PF6, were characterized by elemental analysis and by infrared (IR), UV-Vis, nuclear magnetic resonance (NMR 1H and 13P{1H}) spectroscopies, cyclic voltammetry and X-ray crystallography technique. Additionally, preliminary in vitro tests against human breast (MDA-MB-231) and murine ascitic sarcoma 180 (S180) tumor cell lines were carried out, and compared with cisplatin, a reference drug. The drug concentration at which 50% of the cells are viable relative to the control (IC50) values found for complexes 1, 2, 3 and 4 against MDA-MB-231 tumor cells were around 14.6, 7.6, 3.3 and 0.4 µM, respectively, while against S180 tumor cells these complexes showed IC50 values of 71.9, 31.3, 11.2 and 3.5 µM, respectively. Therefore, the complexes were more active against MDA-MB-231 than S180.

This paper describes a new series of four DNA-intercalating agents with promising anticancer activities, based on ruthenium(II) with the planar ligand dpqQX (dpqQX = dipyrido[3,2-a:2',3'-c]quinoxaline[2,3-b]quinoxaline). The complexes identified as trans-[RuCl2(dppb)(dpqQX)], cis-[RuCl2(dppb)(dpqQX)], ct-[RuCl(CO)(dppb)(dpqQX)]PF6 and ct-[RuCl2(PPh3)2(dpqQX)] (dppb = 1,4-bis(diphenylphosphine)butane and PPh3 = triphenylphosphine) were characterized by 31P{1H} nuclear magnetic resonance (NMR) and infrared spectroscopies, cyclic voltammetry, molar conductance measurements, elemental analysis, mass spectrometry and X-ray diffraction analysis for complex ct-[RuCl2(PPh3)2(dpqQX)]. Their in vitro cytotoxic activities against MDA-MB-213 and MCF-7 breast cancer cells were evaluated and compared with normal L-929 cells. Low drug concentration at which 50% of the cells are viable relative to the control (IC50) values were obtained for all four complexes compared with a reference metallodrug, cisplatin. In addition, DNA affinity studies from titrations, as well as the images obtained by atomic force microscopy (AFM) involving pBR322 plasmid DNA, suggest interactions between the metal complexes and the DNA macromolecule, in which they act as intercalating agents. The intercalation of the complexes with DNA was confirmed by viscosity measurements.

The [Ru(Spym)(bipy)(P–P)]PF6, [Spym = pyrimidine-2-thiolate anion; P–P = 1,2-bis(diphenylphosphino)ethane, 1,3-bis(diphenylphosphino)propane and 1,1'-bis(diphenylphosphino)ferrocene] complexes were synthesized and characterized by spectroscopic, electrochemical and elemental analysis, and by X-ray crystallography. The minimal inhibitory concentration (MIC) of the compounds against Mycobacterium tuberculosis and the complex concentration causing 50% tumor cell growth inhibition (IC50) against breast cancer cells, MDA-MB-231, were determined. All three compounds gave promising values in both tests. It is interesting to mention that all three complexes display MICs against Mycobacteriumtuberculosis showing higher activity than cycloserine, a second line drug used in the treatment of the illness. The complexes interact weakly with the DNA.

O aproveitamento de resíduos urbanos como fontes de matéria orgânica e nutrientes contribui para diminuir a pressão das sociedades modernas sobre o meio ambiente. Por outro lado, a incorporação de matéria orgânica é um meio de se criarem condições edáficas para o estabelecimento de plantas em solos degradados e substratos expostos. Este trabalho visou avaliar a fertilidade e a cobertura vegetal (Paspalum notatum var. saurae Parodi) de um substrato exposto à superfície, tratado com doses crescentes (0 - 76 Mg ha-1, base seca) de lodo de esgoto ou composto de resíduos domésticos. Os resultados indicam que o lodo de esgoto foi capaz de aumentar a CTC e as concentrações de N, P e Zn no substrato enquanto não houve incrementos significativos desses nutrientes no substrato tratado com o composto de resíduos domésticos. A cobertura vegetal do substrato variou de 68 a 96% nos tratamentos com lodo (resposta assintótica) e entre 22 e 67% nos tratamentos com composto (resposta linear), de acordo com a dose aplicada. Valores de CTC e concentrações de N, P e Zn explicaram 94% da variação da cobertura vegetal sobre a superfície da área.

The utilization of urban wastes as organic matter and nutrient source contributes to decrease modern societies pressure on the environment. On the other hand, incorporation of organic matter sources into degraded soils and exposed spoils has been an approach to build edafic conditions for plant growth on such sites. This study aimed to evaluate fertility and vegetative cover (Paspalum notatum var. saurae Parodi) of an exposed spoil treated with increasing rates (0 - 76 Mg ha-1, dry matter basis) of either domestic sewage sludge or municipal composted waste. Results have showed that sewage sludge raised spoil's CEC and contents of N, P and Zn, while composted waste did not. Surface vegetative cover ranged from 68 to 96% for sewage sludge treatments (asymptotic response) and from 22 to 67% composted waste treatments (linear response). Values of CEC and contents of N, P e Zn explained 94% vegetative cover variations on surface area.

A retirada da camada superficial do solo e a escavação do subsolo pela mineração deixam expostos materiais inadequados ao estabelecimento e desenvolvimento de plantas. Nesses locais a regeneração natural é incipiente, de modo que intervenções que visem à melhoria do substrato são necessárias para o restabelecimento da vegetação. Este trabalho teve por objetivo avaliar a evolução física, química e biológica de um substrato minerado no Distrito Federal após a introdução de uma cobertura herbácea de Stylosanthes spp. Os resultados mostram que as operações necessárias para a implantação do estrato herbáceo e o desenvolvimento das plantas melhoraram significativamente os atributos avaliados. Os parâmetros químicos foram os mais modificados e os físicos, os que menos evoluíram após dois anos da revegetação. Houve, ainda, recuperação satisfatória do teor de matéria orgânica do substrato, mas a atividade microbiana permaneceu em cerca de 60% da encontrada em solos sob vegetação nativa de Cerrado.

Removal of superficial soil layer and mining expose the material unsuitable for plant growth. In such areas, natural regeneration is incipient and intervention to improve substrate quality is necessary for the reestablishment of a vegetative cover. This study aimed to evaluate physical, chemical, and biological evolution of a mined substrate in the Federal District of Brazil after the establishment of a Stylosanthes spp. herbaceous cover. Results show that the operations necessary for planting and growth of plants improved all measured parameters. The chemical attributes of substrate were the most improved and physical characteristics were the ones that least evolved two years after the establishment of revegetation. There was a satisfactory recovery of organic matter content, but microbial activity represented only 60% of the value measured in soils under native vegetation.

Normas recentes não permitem que biossólidos com significativas concentrações de patógenos humanos sejam usados na agricultura. Dessa forma, o trabalho visa avaliar a exeqüibilidade de se produzir biossólido isento de patógenos por meio da compostagem e vermicompostagem do lodo de esgoto de Brasília. Serragem e poda de árvores e de grama foram misturadas com lodo de esgoto, como fontes de carbono e material estruturante, em pilhas de compostagem. O composto maduro foi então inoculado com minhocas, para ser vermicompostado. As minhocas se desenvolveram bem e melhoraram as características físicas e sanitárias do biossólido compostado. O lodo de esgoto apresentava, originalmente, 4,7 ovos viáveis de helmintos por grama de matéria seca e o processo de compostagem reduziu essa concentração para valores entre não-detectáveis a 0,34 ovos viáveis de helmintos por grama de material seco, que representa uma eficiência de desinfestação entre 93 e 100%. Não foram detectados ovos viáveis de helmintos após a vermicompostagem e, portanto, o processo se mostrou capaz de produzir biossólidos livres de helmintos, que são permitidos para o uso agrícola no Brasil.

Recent Brazilian regulations do not allow biosolids rich in human pathogens to be used in agriculture. Thus, this work aimed to evaluate the feasibility of producing pathogen-free biosolids by composting and vermicomposting sewage sludge from city of Brasilia. Sawdust and woodchips or yard trimmings were mixed with tertiary sewage sludge as carbon source and bulk agent to build piles bigger than 5 m³. Mature compost was then inoculated with worms to be vermicomposted. Worms developed well and improved the physical and sanitary characteristics of the composted sludge. The sewage sludge originally presented 4.7 viable eggs g-1 of dry solids and the composting process could reduce it to values from non-detectable to 0.34 viable eggs g-1 of dry solids. Such figures represent sanitation efficiencies from 93 to 100%. Non-viable eggs were detected after vermicomposting. Therefore, such a process showed itself capable of producing helminthe-free biosolids, which are allowed for agricultural use in Brazil.