RESUMEN
Nickel, a prevalent metal in the ecosystem, is released into the environment through various anthropogenic activities, leading to adverse effects. This research explored utilizing zeolite scony mobile-5 (ZSM-5) nanoparticles encapsulated in sodium alginate (SA) for nickel (II) removal from aqueous solutions. The adsorption characteristics of SA/ZSM-5 were examined concerning contact duration, initial metal ion concentration, pH level, temperature, and sorbent dosage. The findings revealed that a rising pH reduced Ni (II) uptake by the sorbent while increasing the Ni (II) concentration from 25 to 100 mg L-1 led to a decrease in removal percentage from 91 to 80% under optimal conditions. Furthermore, as sorbent dosage increased from 4 to 16 g L-1, uptake capacity declined from 9.972 to 1.55 mg g-1. Concurrently, SA/ZSM-5 beads' Ni (II) sorption capacity decreased from 96.12 to 59.14% with a temperature increase ranging from 25 to 55 °C. The Ni (II) sorption data on SA/ZSM-5 beads are aptly represented by Langmuir and Freundlich equilibrium isotherm models. Moreover, a second-order kinetic model characterizes the adsorption kinetics of Ni (II) on the SA/ZSM-5 beads. A negative free energy change (ΔG°) demonstrates that the process is both viable and spontaneous. The negative enthalpy values indicate an exothermic nature at the solid-liquid interface while negative entropy values suggest a decrease in randomness. In conclusion, this novel adsorbent exhibits promise for removing nickel from aqueous solutions and could potentially be employed in small-scale industries under similar conditions.
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The phylum Apicomplexa comprises a large group of intracellular protozoan parasites. These microorganisms are known to infect a variety of vertebrate and invertebrate hosts, leading to significant medical and veterinary conditions such as toxoplasmosis, cryptosporidiosis, theileriosis, and eimeriosis. Despite their importance, comprehensive data on their diversity and distribution, especially in riverine environments, remain scant. To bridge this knowledge gap, we utilized next-generation high-throughput 18S rRNA amplicon sequencing powered by PacBio technology to explore the diversity and composition of the Apicomplexa taxa. Principal component analysis (PCA) and principal coordinate analysis (PCoA) indicated the habitat heterogeneity for the physicochemical parameters and the Apicomplexa community. These results were supported by PERMANOVA (P < 0.001), ANOSIM (P < 0.001), Cluster analysis, and Venn diagram. Dominant genera of Apicomplexa in inlet samples included Gregarina (38.54%), Cryptosporidium (32.29%), and Leidyana (11.90%). In contrast, outlet samples were dominated by Babesia, Cryptosporidium, and Theileria. While surface water samples revealed 16% and 8.33% relative abundance of Toxoplasma and Cryptosporidium, respectively. To our knowledge, the next-generation high throughput sequencing covered a wide range of parasites in Egypt for the first time, which could be useful for legislation of the standards for drinking water and wastewater reuse.
Asunto(s)
Babesia , Criptosporidiosis , Cryptosporidium , Toxoplasma , Humanos , Cryptosporidium/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Toxoplasma/genéticaRESUMEN
Microbial degradation of synthetic dyes is considered a promising green dye detoxification, cost-effective and eco-friendly approach. A detailed study on the decolorization and degradation of malachite green dye (MG) using a newly isolated Pseudomonas plecoglossicide MG2 was carried out. Optimization of MG biodegradation by the tested organism was investigated by using a UV-Vis spectrophotometer and the resultant degraded products were analyzed by liquid chromatography-mass spectrometry and FTIR. Also, the cytotoxicity of MG degraded products was studied on a human normal retina cell line. The optimum conditions for the significant maximum decolorization of MG dye (90-93%) by the tested organism were pH 6-7, inoculum size 4-6%, and incubation temperature 30-35 °C, under static and aerobic conditions. The performance of Pseudomonas plecoglossicide MG2 grown culture in the bioreactors using simulated wastewater was assessed. MG degradation (99% at 100 and 150 mg MG/l at an optimal pH) and COD removal (95.95%) by using Pseudomonas plecoglossicide MG2 culture were the best in the tested culture bioreactor in comparison with that in activated sludge or tested culture-activated sludge bioreactors.The FTIR spectrum of the biodegraded MG displayed significant spectral changes, especially in the fingerprint region 1500-500 as well as disappearance of some peaks and appearance of new peaks. Twelve degradation intermediates were identified by LC-MS. They were desmalachite green, didesmalachite green, tetradesmalachite green, 4-(diphenylmethyl)aniline, malachite green carbinol, bis[4-(dimethylamino)phenyl]methanone, [4-(dimethylamino)phenyl][4-(methyl-amino)phenyl]methanone, bis[4-(methylamino)phenyl]methanone, (4-amino- phenyl)[4-(methylamino)phenyl]methanone, bis(4-amino phenyl)methanone, (4-amino phenyl)methanone, and 4-(dimathylamino)benzaldehyde. According to LC-MS and FTIR data, two pathways for MG degradation by using Pseudomonas plecoglossicide MG2 were proposed. MG showed cytotoxicity to human normal retina cell line with LC50 of 28.9 µg/ml and LC90 at 79.7 µg/ml. On the other hand, MG bio-degraded products showed no toxicity to the tested cell line. Finally, this study proved that Pseudomonas plecoglossicide MG2 could be used as an efficient, renewable, eco-friendly, sustainable and cost-effective biotechnology tool for the treatment of dye wastewater effluent.
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Aguas del Alcantarillado , Aguas Residuales , Humanos , Colorantes , Reactores Biológicos , PseudomonasRESUMEN
The aim of this study is to find out a sustainable and cost-effective solution to manage hazardous shock loads from metal finishing and electro-coating industry. Results indicated that the main sources of hazardous wastewater are coming from batch chemical cleaning of degreasing basin (CCDB) (pH 13) and contains very hazardous chemicals, batch chemical cleaning of phosphating basin (CCPB) (pH 1.03) and contains high concentrations of iron (2300 mg/L) and zinc (2400 mg/L) and degreasing basin contents (DBC). Different treatment approaches were investigated. Results indicated that mixing CCDB with CCPB at their actual discharge allowed to form a self-coagulant of metal hydroxide which was utilized to treat the (DBC) followed by sedimentation. Removal efficiency of COD (87%), TSS (94%), and oil and grease (92%) were achieved. To compare the efficiency of this treatment approach, conventional chemical coagulation of DBC was carried out using FeCl3 but the amount was very high. In conclusion, results proved the advantage of using self-coagulation to treat DBC since it eliminates the use of external chemicals and provides an integrated solution for the three main sources of hazardous pollutants. PRACTITIONER POINTS: The manuscript provide an innovative and sustainable solution to the shock loads of hazardous wastewater generated from metal finishing and E-coating industry by utilizing iron-rich wastewater from chemical cleaning of phosphating basin and alkaline wastewater from chemical cleaning of degreasing basin to produce metal hydroxide. The metal hydroxide was cost-effective and technically effectively than external coagulant in treating highly polluted degreasing basin content at due discharge time. Iron-rich wastewater could be used to produce self-coagulant of iron hydroxide. Mixing iron rich wastewater and alkaline wastewater produce iron hydroxide. Iron hydroxide is cost-effective in treating hazardous wastewater of degreasing basin.