ABSTRACT
Tannery sludge (TS) contains high levels of organic matter and chemical elements, mainly chromium (Cr). This can increase its toxicity, rendering it unsuitable for application to soil. However, composting has been proposed as an alternative method for detoxifying TS before its addition to soil. Thus, the aim of this study was to evaluate the phytotoxic and cytogenotoxic potential of untreated (TS) and composted (CTS) tannery sludge in solid and solubilized samples. Seed germination and root growth bioassays were performed with Lactuca sativa, while chromosomal aberrations were assessed using the Allium cepa bioassay. In solid samples, the L. sativa bioassay showed that TS adversely affected germination and root growth, while CTS had a negative affect only on root growth. In solubilized samples, only TS showed significant adverse effects on seed germination and root growth. In both solid and solubilized samples, TS and CTS showed cytotoxic, genotoxic, and mutagenic effects on A. cepa. Thus, results demonstrated that the composting of TS does not result in its complete detoxification. For this reason, TS and CTS cannot be recommended for agricultural use, since they may increase the risk of environmental contamination and crop damage.
Subject(s)
Composting , Soil Pollutants , Agriculture , Sewage , SoilABSTRACT
Annona coriacea é uma árvore frutífera nativa do Cerrado brasileiro que apresenta propriedades nutricionais e farmacológicas. Essa planta possui uma longa história de uso tradicional, sendo utilizada desde a antiguidade pela medicina popular para o tratamento de várias condições patológicas. A compreensão de suas composição química e atividades biológicas fornece a base para apoiar futuras pesquisas e aplicações dessa planta no desenvolvimento de novos produtos alimentícios, agrícolas e farmacêuticos. Nesse sentido, esta revisão busca unir as informações disponíveis sobre a fitoquímica, os usos tradicionais, e as atividades biológicas e nutricionais de A. coriacea. As folhas, sementes, flores e frutos têm demonstrado uma ampla gama de compostos bioativos e apresentam atividades antioxidantes, anti-inflamatórias, antitumorais, analgésicas, antimicrobianas, antiparasitárias e inseticidas. Portanto, essas descobertas demonstram que as folhas, frutos, flores e sementes podem ser utilizados como alimentos funcionais ou como fonte para a obtenção de compostos bioativos para aplicações em alimentos, cosméticos e fármacos.
Subject(s)
Annona , Phytochemicals , Medicine, Traditional , AntioxidantsABSTRACT
The Cerrado biome in the Sete Cidades National Park, an Ecological Reserve in Northeastern Brazil, has conserved its native biodiversity and presents a variety of plants found in other savannas in Brazil. Despite this finding the soil microbial diversity and community structure are poorly understood. Therefore, we described soil bacterial diversity and distribution along a savanna vegetation gradient taking into account the prevailing environmental factors. The bacterial composition was retrieved by sequencing a fragment of the 16S ribosomal RNA gene. The bacterial operational taxonomic units (OTUs) were assigned to 37 different phyla, 96 classes, and 83 genera. At the phylum level, a core comprised by Proteobacteria, Acidobacteria, Actinobacteria, Firmicutes, Verrucomicrobia and Planctomycetes, was detected in all areas of Cerrado. 'Cerrado stricto sensu' and 'Cerradao' share more similarities between edaphic properties and vegetation and also present more similar bacterial communities, while 'Floresta decidual' and 'Campo graminoide' show the largest environmental differences and also more distinct bacterial communities. Proteobacteria (26%), Acidobacteria (21%) and Actinobacteria (21%) were the most abundant phyla within the four areas. All the samples present similar bacteria richness (alpha diversity) and the observed differences among them (beta diversity) were more related to the abundance of specific taxon OTUs compared to their presence or absence. Total organic C, N and P are the main abiotic factors structuring the bacterial communities. In summary, our findings show the bacterial community structure was clearly different across the Cerrado gradient, but that these environments share a bacterial phylum-core comprising Proteobacteria, Acidobacteria, Actinobacteria, Verrucomicrobia and Planctomycetes with other Brazilian savannas.
