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Potentiality of Eisenia fetida to degrade disposable paper cups—an ecofriendly solution to solid waste pollution Texto completo
2015
Arumugam, Karthika | Ganesan, Seethadevi | Muthunarayanan, Vasanthy | Vivek, Swabna | Sugumar, Susila | Munusamy, Vivekanadhan
The aim of the present study was to subject the post-consumer waste, namely paper cups for vermicomposting along with cow dung in three different ratios for a period of 90–140 days employing Eisenia fetida. The post-consumer wastes are a menace in many developing countries including India. This waste was provided as feed for earthworms and was converted to vermicompost. Vermicompost prepared with paper cup waste was analyzed for their physicochemical properties. Based on the physicochemical properties, it was evident that the best manure is obtained from type A (paper cup/cow dung in the ratio 1:1) than type B (paper cup/cow dung in the ratio 1.5:0.5) and type C (paper cup/cow dung in the ratio 0.5:1.5). The results showed that earthworms accelerated the rate of mineralization and converted the wastes into compost with needed elements which could support the growth of crop plants. The predominant bacterial strains in the vermicompost were characterized biochemically as well as by 16S ribosomal RNA (rRNA) gene sequencing. The bacterial strains like Bacillus anthracis (KM289159), Bacillus endophyticus (KM289167), Bacillus funiculus (KM289165), Virigibacillius chiquenigi (KM289163), Bacillus thuringiensis (KM289164), Bacillus cereus (KM289160), Bacillus toyonensis (KM289161), Acinetobacter baumanni (KM289162), and Lactobacillus pantheries (KM289166) were isolated and identified from the final compost. The total protein content of E. fetida involved in vermicomposting was extracted, and the banding pattern was analyzed. During final stages of vermicomposting, it was observed that the earthworm did not act on the plastic material coated inside the paper cups and stagnated it around the rim of the tub. Further, the degradation of paper cup waste was confirmed by Fourier transform infrared spectroscopy analysis. Hence, vermicomposting was found to be an effective technology for the conversion of the paper cup waste material into a nutrient-rich manure, a value-added product.
Mostrar más [+] Menos [-]Immobilization and phytotoxicity of Pb in contaminated soil amended with γ-polyglutamic acid, phosphate rock, and γ-polyglutamic acid-activated phosphate rock Texto completo
2015
Zhu, Jun | Cai, Zhijian | Su, Xiaojuan | Fu, Qingling | Liu, Yonghong | Huang, Qiaoyun | Violante, Antonio | Hu, Hongqing
Pot experiments were conducted to investigate the effects of γ-polyglutamic acid (γ-PGA), phosphate rock (PR), and γ-PGA-activated PR (γ-PGA-PR) on the immobilization and phytotoxicity of Pb in a contaminated soil. The proportion of residual Pb (Re-Pb) in soil was reduced by the addition of γ-PGA but was increased by the application of PR and γ-PGA-PR. The addition of γ-PGA in soil improved the accumulation of Pb in pak choi and decreased the growth of pak choi, suggesting the intensification of Pb phytotoxicity to pak choi. However, opposite effects of PR and γ-PGA-PR on the phytotoxicity of Pb to pak choi in soil were observed. Moreover, in the examined range, γ-PGA-PR activated by a higher amount of γ-PGA resulted in a greater proportion of Re-Pb in soil and weaker phytotoxicity of Pb to pak choi. The predominance of γ-PGA-PR in relieving the phytotoxicity of Pb was ascribed mainly to the increase of soil pH and available phosphate after the amendment, which could facilitate the precipitation of Pb in soil and provide pak choi with more phosphorus nutrient.
Mostrar más [+] Menos [-]Remediation of nitrate-contaminated water by solid-phase denitrification process—a review Texto completo
2015
Ashok, Vaishali | Hait, Subrata
The paper presents a compilation of various autotrophic and heterotrophic ways of solid-phase denitrification. It covers a complete understanding of various pathways followed during denitrification process. The paper gives a brief review on various governing factors on which the process depends. It focuses mainly on the solid-phase denitrification process, its applicability, efficiency, and disadvantages associated. It presents a critical review on various methodologies associated with denitrification process reported in past years. A comparative study has also been carried out to have a better understanding of advantages and disadvantages of a particular method. We summarize the various organic and inorganic substances and various techniques that have been used for enhancing denitrification process and suggest possible gaps in the research areas whi'ch are worthy of future research.
Mostrar más [+] Menos [-]Research on self-purification capacity of Lake Taihu Texto completo
2015
Han, Tao | Zhang, Hongju | Hu, Weiping | Deng, Jiancai | Li, Qinqin | Zhu, Guie
An effective measure to cope with eutrophication of lakes is to remove nutrients that can cause algal blooming by taking advantage of natural water purification processes. Here, the term “purification” is defined, in a wide sense, as the potential role of a water body to contribute to the reduction of pollutants and thus controlling eutrophication. Also regarded as a kind of ecological regulating services, biological purification involves various processes concerning seasonal nutrient fixation, such as uptake by aquatic macrophyte, biofouling onto foliage substrates, feeding by organisms in higher trophic level, and eternal loss or removal of substance from the water. In order to evaluate the water purification ability, a numerical lake ecosystem model (EcoTaihu) was developed and applied to Lakes Taihu. The model includes the biological interactions between pelagic compartments (phytoplankton and zooplankton, detritus, dissolved organic matter, fish, and nutrients). Under dynamic forcing of meteorological and hydrological parameters, the model was run over years to evaluate the annual nutrient cycles and purification functions. The reproducibility of the model was validated for water body by comparison with the field data from the water quality monitoring campaign. Numerical results revealed that self-purification capacity of nitrogen of Lake Taihu in years 2006, 2008, and 2010 is 4.00 × 10⁴, 4.27 × 10⁴, and 4.11 × 10⁴ ton, respectively, whereas self-purification capacity of phosphorus of Lake Taihu in years 2006, 2008, and 2010 is 1.56 × 10³, 1.80 × 10³, and 1.71 × 10³ ton, respectively.
Mostrar más [+] Menos [-]Phytoremediation of carbamazepine and its metabolite 10,11-epoxycarbamazepine by C3 and C4 plants Texto completo
2015
Ryšlavá, Helena | Pomeislová, Alice | Pšondrová, Šárka | Hýsková, Veronika | Smrček, Stanislav
The anticonvulsant drug carbamazepine is considered as an indicator of sewage water pollution: however, its uptake by plants and effect on metabolism have not been sufficiently documented, let alone its metabolite (10,11-epoxycarbamazepine). In a model system of sterile, hydroponically cultivated Zea mays (as C₄ plant) and Helianthus annuus (as C₃ plant), the uptake and effect of carbamazepine and 10,11-epoxycarbamazepine were studied in comparison with those of acetaminophen and ibuprofen. Ibuprofen and acetaminophen were effectively extracted from drug-supplemented media by both plants, while the uptake of more hydrophobic carbamazepine was much lower. On the other hand, the carbamazepine metabolite, 10,11-epoxycarbamazepine, was, unlike sunflower, willingly taken up by maize plants (after 96 h 88 % of the initial concentration) and effectively stored in maize tissues. In addition, the effect of the studied pharmaceuticals on the plant metabolism (enzymes of Hatch-Slack cycle, peroxidases) was followed. The activity of bound peroxidases, which could cause xylem vessel lignification and reduction of xenobiotic uptake, was at the level of control plants in maize leaves contrary to sunflower. Therefore, our results indicate that maize has the potential to remove 10,11-epoxycarbamazepine from contaminated soils.
Mostrar más [+] Menos [-]Internet of Things technology-based management methods for environmental specimen banks Texto completo
2015
Peng, Lihong | Wang, Qian | Yu, Ang
The establishment and management of environmental specimen banks (ESBs) has long been a problem worldwide. The complexity of specimen environment has made the management of ESB likewise complex. Through an analysis of the development and management of ESBs worldwide and in light of the sophisticated Internet of Things (IOT) technology, this paper presents IOT technology-based ESB management methods. An IOT technology-based ESB management system can significantly facilitate ESB ingress and egress management as well as long-term storage management under quality control. This paper elaborates on the design of IOT technology-based modules, which can be used in ESB management to achieve standardized, smart, information-based ESB management. ESB management has far-reaching implications for environmental management and for research in environmental science.
Mostrar más [+] Menos [-]Illumina MiSeq sequencing investigation on the contrasting soil bacterial community structures in different iron mining areas Texto completo
2015
Hongchen, | Si, Yanxiao | Xing, Yi | Li, Yang
Mine activities leaked heavy metals into surrounding soil and may affected indigenous microbial communities. In the present study, the diversity and composition of the bacterial community in soil collected from three regions which have different pollution degree, heavy pollution, moderate pollution, and non-pollution, within the catchment of Chao River in Beijing City, were compared using the Illumina MiSeq sequencing technique. Rarefaction results showed that the polluted area had significant higher bacterial alpha diversity than those from unpolluted area. Principal component analysis (PCA) showed that microbial communities in the polluted areas had significant differences compared with the unpolluted area. Moreover, PCA at phylum level and Matastats results demonstrated that communities in locations shared similar phyla diversity, indicating that the bacterial community changes under metal pollution were not reflected on phyla structure. At genus level, the relative abundance of dominant genera changed in sites with degrees of pollution. Genera Bradyrhizobium, Rhodanobacter, Reyranella, and Rhizomicrobium significantly decreased with increasing pollution degree, and their dominance decreased, whereas several genera (e.g., Steroidobacter, Massilia, Arthrobacter, Flavisolibacter, and Roseiflexus) increased and became new dominant genera in the heavily metal-polluted area. The potential resistant bacteria, found within the genera of Thiobacillus, Pseudomonas, Arthrobacter, Microcoleus, Leptolyngbya, and Rhodobacter, are less than 2.0 % in the indigenous bacterial communities, which play an important role in soil ecosystem. This effort to profile the background diversity may set the first stage for better understanding the mechanism underlying the community structure changes under in situ mild heavy metal pollution.
Mostrar más [+] Menos [-]Comparability of behavioural assays using zebrafish larvae to assess neurotoxicity Texto completo
2015
Legradi, J. | el Abdellaoui, N. | van Pomeren, M. | Legler, J.
Testing of compounds for neurotoxicity has become increasingly important in recent years. It has been shown that neurological disorders like autism may be related to chemical exposures, which may play a crucial role in the progression of these diseases. Special attention has been be given to the substances causing developmental neurotoxicity as the developing nervous system is more vulnerable to impacts by chemicals than the adult nervous system. The zebrafish (Danio rerio) is a well-established model species in developmental biology and an emerging model in behavioural and neurological studies. Zebrafish larvae display numerous behavioural patterns highly similar to rodents and humans. Their physical characteristics make them well suited for automated high-throughput screening. In the last years, the number of behavioural studies conducted with zebrafish larvae has increased notably. The goal of this review is to provide an overview of behavioural assays commonly used to test substances for developmental neurotoxicity. Literature from 1995 to 2014 was reviewed and focussed on assays performed with zebrafish larvae younger than 7 days post fertilization (dpf). The behavioural tests were scrutinized, and parameters describing the different experimental setups were defined. In the next step, we investigated if differences in the experimental parameters alter the outcome of the test. In order to test the comparability of behavioural assays, we analysed several studies using ethanol, valproate and pentylenetetrazole as model substances. Based on our findings, we provide recommendations which could help improve future behavioural studies performed with zebrafish larvae.
Mostrar más [+] Menos [-]Solar light (hv) and H2O2/hv photo-disinfection of natural alkaline water (pH 8.6) in a compound parabolic collector at different day periods in Sahelian region Texto completo
2015
Ndounla, J. | Pulgarin, C.
The photo-disinfection of natural alkaline surface water (pH 8.6 ± 0.3) for drinking purposes was carried out under solar radiation treatments. The enteric bacteria studied were the wild total coliforms/Escherichia coli (10⁴ CFU/ml) and Salmonella spp. (10⁴ CFU/ml) naturally present in the water. The photo-disinfection of a 25-l water sample was carried out in a solar compound parabolic collector (CPC) in the absence and in the presence of hydrogen peroxide (H₂O₂). The addition of H₂O₂ (10 mg/L) to the sample water was sufficient to enhance the photo-disinfection and ensure an irreversible lethal action on the wild enteric bacteria contents of the sample. The inactivation kinetic of the system was significantly enhanced compared to the one carried out without H₂O₂ addition. The effect of the solar radiation parameters on the efficiency of the photo-disinfection were assessed. The pH has increased during the treatment in all the photo-disinfection processes (hv and H₂O₂/hv). The Salmonella spp strain has shown the best effective inactivate time in alkaline water than the one recorded under acidic or near-neutral conditions. The evolution of some physico-chemical parameters of the water (turbidity, NO₂ ⁻, NO₃ ⁻, NH₄ ⁺, HPO₄ ²⁻, and bicarbonate (HCO₃ ⁻)) was monitored during the treatment. Finally, the possible mechanistic process involved during the enteric bacteria inactivation was suggested.
Mostrar más [+] Menos [-]Chromium and nickel in Pteridium aquilinum from environments with various levels of these metals Texto completo
2015
Kubicka, Kamila | Samecka-Cymerman, Aleksandra | Kolon, Krzysztof | Kosiba, Piotr | Kempers, Alexander J.
Pteridium aquilinum is a ubiquitous species considered to be one of the plants most resistant to metals. This fern meets the demands for a good bioindicator to improve environmental control. Therefore, it was of interest to survey the accumulation of Cr and Ni in the rhizome and fronds of this species collected in Lower Silesia (SW Poland) of serpentinite rich in Cr and Ni and granite poor in these metals. Additionally, concentrations of Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn were measured in granite and serpentinite parent rocks, soils, and in P. aquilinum (rhizome and fronds). The experiment was carried out with rhizomes of ferns from both types of soils placed in pots supplemented with 50, 100, and 250 mg kg⁻¹ of Cr or Ni or both elements together. At a concentration of 250 mg kg⁻¹ of Cr, Ni, or Cr + Ni, fronds (from granite or serpentinite origin) contained significantly higher Cr and Ni concentrations when both metals were supplied together. In the same concentration of 250 mg kg⁻¹ of Cr, Ni, or Cr + Ni, rhizomes (from granite or serpentinite origin) contained significantly higher Cr and Ni concentrations when both metals were supplied separately. The explanation of metal differences in the joint accumulation of Cr and Ni on the rhizome or frond level needs further investigation. The lack of difference in Cr and Ni concentration in the rhizome and fronds between experimental P. aquilinum collected from granite and serpentinite soils may probably indicate that the phenotypic plasticity of this species is very important in the adaptation to extreme environments.
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