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Decolorization of Textile Dyes by Extracellular Enzymes Produced from Trametes sanguinea and Perenniporia taephropora Immobilized on Natural Media
2024
Siriorn Boonyawanich, Nipon Pisutpaisal and Saowaluck Haosagul
The color of textile wastewater is still a main problem in wastewater treatment by biological processes. The colored effluents from textile factories usually exceed effluent standards. Therefore, various innovations were developed to treat textile wastewater for decolorization in the effluents. This research aims to decolorize textile wastewater by immobilizing white rot fungi degradation. At first, the 11 fungal stains were tested to find the decolorized efficiency then the high decolorized efficiency fungal stains were immobilized on four material media, namely water hyacinth stalks, coconut husk, corn cob, and loofah. After that, the immobilized fungi were cultivated in the culture media at 30, 60, and 120 C/N ratios, respectively. The results showed that Trametes sanguinea and Perenniporia tephropora were two stains with a high decolorized efficiency of 68.8% and 67.5% respectively, and the decolorized efficiency was increased when immobilized on loofahs and fed with 120 C/N ratio medium. In a comparison of two fungal stains, P. tephropora was found more suitable for the decolorization of textile wastewater than T. sanguinea because T. sanguinea could produce red-orange pigments that induced the colored enhancement in wastewater over time. Finally, immobilized P. tephropora was cultivated in a 120 C/N ratio medium within a 10 L continuous stirred tank reactor (8 L working volume) to investigate the decolorized efficiency, enzymatic activity, and repeated batch. It was found that three repeated cycles were carried out by reusing the immobilized P. tephropora and the highest decolorized efficiency was 63.4%. The enzymatic activity of laccase, manganese peroxidase, and lignin peroxidase was 15.5 U/L, 85.9 U/L, and 0 U/L, respectively
Afficher plus [+] Moins [-]Evaluating the Stages of Environmental Pollution and Vital Indicators in the Qayyarah Refinery Area, Mosul, Iraq
2024
Juomana Jabbar Saeed, Maryam Jasim Hasan, Estabraq Mohammed Ati, Reyam Naji Ajmi, Abdalkader Saeed Latif and Hala Ahmed Rasheed
Oil spills can have varying degrees of impact on the aquatic environment depending on factors such as the type of oil spilled, the volume released, and the ecosystem affected because crude oil and refined petroleum contain harmful substances such as hydrocarbons, heavy metals, and toxic chemicals. When released into the water, these substances can have immediate and long-term effects on marine life. This research aims to find the factors affecting the degree of pollution from oil spills on the aquatic environment and the areas adjacent to the Qayyarah refinery in northern Iraq. Combines the fuzzy comprehensive evaluation method and the analytical hierarchy process to evaluate the degree of pollution from oil spill incidents in the areas adjacent to the refinery. The statistical analysis showed that there were statistically significant differences and that the value of the correlation coefficient was positive between exchanged cadmium, residual cadmium, exchanged lead, where the lead exchange rate ranged correlation coefficient at a minimum R² 0.674 and a clear increase in the number of bacteria indicating contamination the total number of bacteria coli, fecal coliform bacteria, and fecal strep bacteria (where the numbers of coliform bacteria ranged 102 × 102- (cells/011 mL, and fecal coliform bacteria were between 160 × 102 cells/011 mL. These rates are environmental and vital indicators of the presence of significant levels of organic pollution and evidence of the presence of microorganisms dangerous to the health of residents and living organisms.
Afficher plus [+] Moins [-]Combined Application of Biochar and Silicon Fertilizer for Improved Soil Properties and Maize Growth
2024
Muhammad Wasil Bin Abu Bakar, M. K. Uddin, Susilawati Kasim, Syaharudin Zaibon, S. M. Shamsuzzaman, A. N. A. Haque and A. Reza
Biochar can be a good soil amendment to reduce the soil pH, increase crop growth rate, and improve the efficient use of fertilizer. Other than that, silicon fertilizer also would promote photosynthetic ability on plant development that would help to produce high yield. In this work, a series of experiments was conducted to observe the effect of rice husk biochar and silicon fertilizer on the maize growth rate and soil pH. A 45-day pot experiment in the greenhouse with three replicates of 9 experimental treatment combinations of RHB at two rates (5 and 2.5 t.ha-1) with silicon fertilizer at three rates (125%, 100%, 75%), sole biochar (10 t.ha-1), sole silicon fertilizer (100%) and control (NPK) to observe the best rate and combination to improve growth rate and change in soil chemical in acid soil. The result showed that the co-application of sole biochar and biochar with Silicon significantly improved growth development, increased photosynthesis rate, altered soil pH, and reduced Fe concentration compared to control. The plant height increased 88.35% from T4 (5 t.ha-1 RHB + 100% Si) compared to the control and the conductance was higher in T4 (0.53) followed by T8 (0.438) while T1 (0.071) recorded the lowest conductance. The shoot fresh weight was higher in T4 (127.83 g) followed by T8 (57.14 g). However, the weight increased by 343.7% at T4 followed by T8 (2.5 t.ha-1 RHB + 75% Si) at 98.33%. The highest pH increment of 1.24 units (T1 = 5.53, T4 = 6.77) of soil pH was noted from T4 (5 t.ha-1 RHB + 100% Si) compared to control (NPK), and the highest total Fe in soil was observed from T1 (442.30 mg.kg-1). The current study results showed that T4 (50% RHB + 100% Silicon) was the best treatment over the other rates of RHB and silicon increased plant height, photosynthetic rate, and biomass.
Afficher plus [+] Moins [-]A Review on Bioremediation of Tannery Effluent using Immobilized Bacteria
2024
J. Raveena Jayam and Priya Chokkalingam
Tannery effluent is a significant contributor to contaminants such as heavy metals within the ecosystem. Effluents generally contain heavy metals, and they also contain more bacteria that can thrive in such an environment. Bioremediation has ancestrally been performed using bacteria; in recent decades, the implementation of “immobilized” bacteria has acquired recognition as an intriguing technique due to manifold assistance. This review systematizes a humongous amount of extant literature on multifarious toxicants that can be tackled with immobilized bacteria. We further explore assorted deterministic facets using immobilized bacteria for environmental remediation with an emphasis on encapsulation in biomaterials and their role in detoxifying toxic compounds. We explore multiple techniques for immobilizing bacteria in numerous complementary arrays incorporating multiple species of bacteria, factors that influence the remediation process, such as bioreactor layouts used in pilot, lab-scale applications. Exploits and drawbacks of using immobilized bacteria in fermenters to treat tannery effluent are also described. The imperishable future aspects, recovery of significant commodities, in addition to bioremediation, represent an important incentive of the immobilized treatment process that makes more cost-effective, legitimate treatment enforcement that is also congruent with the precepts of the bioeconomy.
Afficher plus [+] Moins [-]Navigating Nepal’s Economic Growth and Carbon Emissions: Insights into the Environmental Kuznets Curve (EKC)
2024
R. Adhikari, B. Niroula and S. K. Singh
This research aims to employ the Autoregressive Distributed Lag (ARDL) method within the insight into the Environmental Kuznets Curve (EKC) to verify whether EKC exists in the Nepalese economy. In this research, variables were used, such as carbon emissions per capita, GDP per capita, energy use per capita, trade volume, and urbanization from 1980 to 2021, and the ARDL method was used. The data has been taken in this research except trade volume from the World Bank and the Ministry of Finance, Nepal. The data sets are converted into the natural logarithmic form to minimize the problem of heteroskedasticity. The findings provide compelling evidence for the existence of the EKC in Nepal, that economic growth has an inverted U-shaped impact on carbon emissions. In the early stages of development, economic growth leads to rising carbon emissions, but in the later stages, economic growth becomes associated with declining emissions. Besides economic growth, per capita energy consumption and urbanization emerge as significant drivers of carbon emissions. However, the trade volume is not found to be the driving factor of carbon emissions. The findings of this study have significant policy implications for global climate change issues and Nepal’s transition from an underdeveloped to a developing nation. To achieve harmonious economic growth and emissions reduction, donor countries and agencies to partner with Nepal in its ambitious endeavors. This partnership can take shape through multifaceted support as fueling socio-economic progress that aligns with Nepal’s commitment to reduce carbon emissions, ensuring that development and sustainability walk together. This research recommends the government of Nepal electrify the transportation landscape by incentivizing the adoption of electric vehicles, paving the way for cleaner air and a healthier planet, empowering Nepal’s natural guardians by strengthening public and private forest programs, safeguarding invaluable ecosystems and biodiversity and curbing the tide of waste mismanagement through strict regulations and robust enforcement, transforming a potential threat into a source of innovation and resourcefulness. These measures, aligned with sustainable employment generation, can pave the way for a brighter and greener future for Nepal.
Afficher plus [+] Moins [-]Microbial Fuel Cell: Optimizing Graphene-Sponge Anode Thickness and Chamber pH Using Taguchi Experimental Method
2024
Emilio Steven C. Navarro and Melissa May M. Boado
The rapid consumption of fossil fuels has led to calls to switch from non-renewable to renewable energy sources. Microbial fuel cells are a promising technology that simultaneously treats wastewater and produces power. This study used the Taguchi Experimental method to optimize anode thickness and pH to obtain the maximum power density of an air-cathode microbial fuel cell (ACMFC). The graphene-sponge (G-S) anode thickness and chamber pH were selected as operating parameters, with their corresponding levels. The L9 orthogonal array was chosen for the experimental design. According to the Taguchi Method, the optimum G-S anode thickness and chamber pH were determined to be 1.0 cm and 8.0, respectively. A confirmatory run was performed under these optimum conditions, and the maximum power density observed was 707.75 mW·m−3. Analysis of variance (ANOVA) was conducted to identify the percentage contributions of the operating parameters to the process, which were found to be 30.66% for pH and 69.34% for anode thickness.
Afficher plus [+] Moins [-]Emerging Issues in Energy Sustainability: A Systematic Review and Research Agenda
2024
Aqsa Anjum, Jahangir Chauhan, Marghoob Enam and Irfan Ali
This research paper seeks to investigate and categorize previous studies to understand better the role of energy generation technology in promoting sustainable development of a country country. The primary aim of this review is to identify and emphasize key issues related to energy sustainability. The study employs a systematic review approach, drawing on academic publications from the Web of Science and Scopus database. The analysis reveals five key issues: the nexus between energy generation and greenhouse gas emissions, energy generation and employment, the impact of energy generation and land use intensity, the association between energy generation and water footprint, and the nexus between energy generation and human health. This study delves into the theoretical dimensions of research concerning the interplay between energy sustainability and various aspects of energy generation technologies. Furthermore, it contributes to the existing body of knowledge concerning Sustainable Development Goal 7, with the overarching goal of enhancing both human well-being and economic prosperity through advancements in energy generation technologies. The study comprehensively explores the subject matter, offering an in-depth analysis of energy sustainability. Its unique contribution lies in its extensive examination of multiple facets of energy sustainability, making it a significant addition to the field of research.
Afficher plus [+] Moins [-]Saccharification of Different Delignified Sawdust Masses from Various Trees Along the Lagos Lagoon in Nigeria
2024
N. A. Ndukwe, J. B. M. Seeletse and J. P. H. van Wyk
Sawdust, a major waste product of the forestry industry, is accumulating along the Lagos Lagoon in Lagos, Nigeria, without it being effectively managed. Besides its use in The saccharification of sawdust could contribute to the development of renewable energy sources and feedstock for bioproduct development. The process is, however, not that straightforward as variables such as the type of cellulase enzyme, pretreatment of the cellulose substrate, and optimizing of cellulase to cellulose ratio are a few that need to be optimized for the process to be effective in terms of glucose production.manufacturing sound-absorbing boards to reinforce concrete beams and for energy purposes, its potential as a renewable energy source and feedstock for bio-product development has not yet been realized. Cellulose, a glucose biopolymer and structural component of cellulose can be hydrolyzed by a hydrolytic enzyme known as cellulase. During the process, the enzyme breaks the B-1,4-glucosidic bond, which keeps the glucose units together, and by acting on this bond, numerous glucose units are released. As part of sawdust, the cellulose molecule is not freely available for the degradation action of the cellulase enzyme as it is strongly associated with lignin, which acts as bio-glue, keeping cellulose and hemicellulose together. Delignification is an effective technique that was used to make the sawdust from ten different trees along the Lagos Lagoon in Nigeria more susceptible to saccharification by cellulase isolated from the fungus Aspergillus niger. Delignified and non-delignified sawdust masses between 2 mg and 10 mg were incubated with the A. niger cellulase solution (2 mg.mL-1), whereafter, the amount of sugar produced by the cellulase action was determined. The percentage saccharification of each sawdust material was also linked with the amount of sugar produced during cellulase action. From these investigations was concluded that delignification increased sugar production when almost all the masses of different sawdust materials were degraded. It was also observed that the ratio of sawdust mass to enzyme concentration is an important variable that influences the effectiveness of the saccharification process. The percentage saccharification of the various sawdust materials was also determined, and it indicated that the highest percentage of saccharification was not obtained when the highest amount of sawdust was degraded, producing the highest amount of sugar.
Afficher plus [+] Moins [-]Understanding the differential impacts of two antidepressants on locomotion of freshwater snails (Lymnaea stagnalis)
2024
Raman, Nandini Vasantha | Dubey, Asmita | van Donk, Ellen | von Elert, Eric | Lürling, Miquel | Fernandes, Tânia V. | de Senerpont Domis, Lisette N.
There is growing evidence of negative impacts of antidepressants on behavior of aquatic non-target organisms. Accurate environmental risk assessment requires an understanding of whether antidepressants with similar modes of action have consistent negative impacts. Here, we tested the effect of acute exposure to two antidepressants, fluoxetine and venlafaxine (0–50 µg/L), on the behavior of non-target organism, i.e., freshwater pond snail, Lymnaea stagnalis. As compounds interact with chemical cues in the aquatic ecosystems, we also tested whether the effects altered in the presence of bile extract containing 5α-cyprinol sulfate (5α-CPS), a characterized kairomone of a natural predator, common carp (Cyprinus carpio). Behavior was studied using automated tracking and analysis of various locomotion parameters of L. stagnalis. Our results suggest that there are differences in the effects on locomotion upon exposure to venlafaxine and fluoxetine. We found strong evidence for a non-monotonic dose response on venlafaxine exposure, whereas fluoxetine only showed weak evidence of altered locomotion for a specific concentration. Combined exposure to compounds and 5α-CPS reduced the intensity of effects observed in the absence of 5α-CPS, possibly due to reduced bioavailability of the compounds. The results highlight the need for acknowledging different mechanisms of action among antidepressants while investigating their environmental risks. In addition, our results underline the importance of reporting non-significant effects and acknowledging individual variation in behavior for environmental risk assessment.
Afficher plus [+] Moins [-]Urban Indian Environment in the Context of a Pandemic
2024
Abhijith. S., Akshara S. N. and P. P. Nikhil Raj
The spread of the Coronavirus disease 2019 (COVID-19) has impacted human life severely since November 2019. The urban centers in the world, especially, were highly affected by the diseases. Several socioeconomic and environmental factors probably enhanced the spread of the pandemic and consequent mortality. Many studies examining environmental factors, such as air quality, in urban centers indicate the roles of those factors in the spread of diseases and consequent mortality. However, other socioeconomic factors that directly or indirectly elevate the mass death of people are seldom studied. The present study explores the socioeconomic factors and air quality influencing COVID-19 deaths in urban India. We randomly selected 19 Indian cities and collected each city’s socioeconomic and air quality data from reliable and open sources. The data were analyzed using multivariate data analysis techniques using R statistics. The results showed significant positive relationships, population, and total area of the urban centers.
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