Showing papers by "Arci Dirceu Wastowski published in 2021"

Description of the component properties of species of bamboo: a review

Abstract: This study aimed to describe the component properties of adult stems of different species of bamboo through a literature review. The data of holocellulose (cellulose + hemicellulose), lignin, ashes content, total extractives contents, and elemental chemical composition of bamboo was compared with other lignocellulosic materials. In the final considerations, it was found that there is similarity in the average holocellulose content between the species and genera of bamboo, tree species, and other alternative materials that are used in industrial processes. The lignin content varied among tree species, bamboo, and alternative materials, wherein the bamboo presented the intermediate value. The biomasses show hydrogen/carbon ratios from 0.12 to 0.14, indicating that they are highly carbonized. The average value oxygen/carbon ratios of bamboo was 0.96, which indicates there is a higher hydrophobicity in its surface. The average oxygen value of bamboo species was 44.04%, bottom than that found for wood (47.42%); the high content of oxygen leads to a higher reactivity, wherein fast biomass volatilization occurs during the thermal degradation process. The presence of oxygen decreases the energy density as well as the miscibility in hydrocarbon fuels. The highest average values ​of extractives were found for bamboo, while the other groups of species showed similar values. The highest ash content occurred in the group of species of alternative materials, bamboo also presented high values according to specific standards.

Water quality in individual groundwater supply systems in Southern Brazil

Abstract: This study aimed to evaluate the potability of drinking water in ten municipalities of Rio Grande do Sul State, Brazil, distributed in rural and urban areas, with three different sources: springs, shallow wells, and deep wells. The water quality parameters analyzed from 2017 to 2019 were: pH, temperature, apparent and true color, turbidity, electrical conductivity, total alkalinity, total hardness, nitrate, total phosphorus, total iron, fluoride, biochemical oxygen demand, total coliforms, and Escherichia coli . A macroscopic analysis was also conducted in the surrounding of sampling points. According to the Brazilian and the WHO (World Health Organization) guidelines, some of the analyzed variables, in some sampling points, were in disagreement with the current both guidelines, which are pH, apparent color, turbidity, total iron, total coliforms, and Escherichia coli . The surveillance showed that the deeper the water is abstracted the less are natural and anthropogenic interferences in physical, chemical, and microbiological characteristics of the water; and the protection of the location where the water is abstracted improves its quality. Nonetheless, for the sampled waters it is necessary a disinfection process for posterior human consumption.

Electro-removal of copper, chromium, and arsenic from chromated copper arsenate treated waste wood

Abstract: Wood is a renewable material considered eco-friendly and used for various purposes. While wood treated with chromated copper arsenate (CCA) does not deteriorate, its final disposal may entail risks due to the concentration and toxicity of the components. The removal of CCA from wood can be achieved in different ways. This study focuses on the reduction of the concentrations of Cu, Cr, and As chemical species by the electro-removal technique, aiming to obtain biomass with low deleterious potential that would allow multiple uses or safe disposal in landfills. The analytical results showed reductions of 79.5, 87.4, and 81.3% in the mean concentrations of Cu, Cr, and As, respectively. It is worth mentioning the occurrence of the fungus Xylaria sp. after treatment 6 (60 min, 5 g, and 25 V), further suggesting that the method was effective. Samples of these fungi were identified from isolates by culture in medium, DNA extraction, and sequencing of the Internal Transcribed Spacer (ITS) region.

Water quality variables and emerging environmental contaminant in water for human consumption in Rio Grande do Sul, Brazil

Abstract: This research aimed to qualify and quantify physical, chemical, microbiological and emerging environmental contaminants, pharmaceuticals and pesticides in spring waters, which are used for human consumption under different land use and occupation conditions. These conditions were: native forests and swine farming, as well as soy and tobacco crops in two consecutive seasons. Due to the microbiological variables and the pH and apparent color, the spring water studied is not potable, as it does not comply with the legislation due to the contribution of the total coliforms found in the native forest springs. Pharmaceuticals and pesticides were found in the land use and occupation conditions under study, which shows that land uses do not interfere with emerging environmental contaminant variables.

Biotechnology: identification and evaluation of the Bacillus cereus amylolytic activity

Abstract: Biotechnology is the branch of science that uses molecules, viruses, microorganisms, cells, animals, plants or part of them in technological processes to generate benefits for humans, to flora, fauna and the environment. In this context, enzymes are natural biocatalysts that present substrate specificity and extreme importance to vital processes, as they develop indispensable functions in biochemical reactions of cell metabolism, and can be used in biotechnological processes. Knowing the human needs, for a world population of about 7.7 billion people and the functional usefulness of enzymes, there is, on the one hand, a gigantic demand for the consumption of various products in the agricultural sector, processed and industrialized, such as: food, beverages, clothing in the textile sector, medicines, vaccines, cosmetics in the chemical-pharmaceutical sector, as well as in the production of paper and fuels, in which enzymes, mainly amylases, have been widely used in production processes. In this work, experiments were carried out with the wild Bacillus cereus bacterium to verify the production of amylases, the results obtained could demonstrate the formation of amylolysis halos around the colonies in Petri dishes containing Tryptic Soy Agar + starch (1%) medium, pH 7.3 and grown in a biological oven at 37oC for 24 hours, when revealed in iodine vapor; the Amylolysis Index (AI) was 3.3 and the efficiency of starch substrate degradation by amylases was greater than 90% in the evaluated treatments.

Evaluation of the Electro-removal Technique of the Treated Wood Using the Accelerated Decaying Fungus Test

Abstract: Waste from treated wood can be hazardous to the environment and human health. Therefore, research is needed to investigate what to do with this waste. The electro-removal technique is a viable technique to remove the copper, chromium and arsenic metals contained in the CCA-treated wood. But is the CCA really removed? the present study investigated this cause, using the living organism Trametes versicolor to verify this hypothesis.

Efeito alelopático e análise química de extratos hidroalcóolicos de Baccharis dracunculifolia, Baccharis trimera e Baccharis gaudichaudiana sobre cultivar de Lactuca sativa L.

Abstract: The present work aims to study the effect of hydroalcoholic extracts of three carqueja species (Baccharis trimera, Baccharis dracunculifolia and Baccharis gaudichaudiana) at different concentrations on the germination and initial growth of lettuce (Lactuca sativa) and the identification of volatile compounds present in these species . Lettuce seeds were distributed in a gerbox containing germitest paper. The experimental design used was completely randomized (DIC) in a bifactorial scheme (3x5), representing three species of carquejas and five concentrations of extracts: 0.00, 0.02, 0.03, 0.04 and 0.05%, with four repetitions. The experiment was maintained for a period of seven days in B.O.D. with a temperature of 17.5 °C. The chemical analysis of the constituents belonging to the three species analyzed was performed by gas chromatography coupled with mass spectrometry (CG/MS - Shimadzu, model QP 5050A). The chemical composition of the carquejas resulted in 29 different chemical compounds, each Baccharis species has a specific compound that represents between 24 and 25% of its total chemical composition, namely (-)-Spathulenol (24%), Alloaromadendrene oxide (25%) and 3-Cyclohexen-1-one, 3,5,5-trimethyl- (24.63%) for B. dracunculifolia, B. gaudichaudiana and B. trimera, respectively. The results indicate that B. trimera has allelopathic potential to favor lettuce germination. The species B. dracunculifolia and B. gaudichaudiana did not influence the germination of lettuce seeds in the analyzed concentrations. The extracts of B. trimera, B. dracunculifolia and B. gaudichaudiana negatively influenced the root length and germination speed index (IVG) with the increase in extract concentrations.