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Saccharification of Various Wastepaper Materials by Cellulase from Brown Garden Snail (Cornu aspersum) at Different Incubation pH Values
2023
Ndlovu, T. M. | Van Wyk, J. P. H.
Increased solid waste pollution and the negative effect of fossil fuel consumption on the environment are issues that would require more scientific attention and application to deal effectively with these phenomena. Wastepaper, a major component of solid waste, is classified as organic waste due to the presence of cellulose, a glucose-based biopolymer that is part of its structural composition. The saccharification of cellulose into glucose, a fermentable sugar, can be achieved with a hydrolytic enzyme known as cellulase. Although cellulase from fungal species such as Trichoderma, Aspergillus, and Penicillium are well described, knowledge about cellulase isolated from the brown garden snail is limited as it has not been the subject of many research endeavors. The waste paper has been described as a suitable resource for bio-energy development due to cellulose, a structural component of this bio-material that can be degraded into glucose, a fermentable sugar. Although paper materials such as newspaper, office paper, filter paper, Woolworths and Pick and Pay (retailers) advertising paper, as well as foolscap paper, were saccharified by different cellulases, the degradation of these paper materials by garden snail cellulase is a novel investigation from our laboratory. With the effects of temperature and incubation time on this cellulase action when degraded paper materials have already been investigated and reported, this study dealt with the garden snail cellulase action when degraded paper materials at different pH values. Most of the paper materials were degraded optimally at a pH value of 6.0, while optimum saccharification was observed at pH 4.5 when newspaper and brown envelope paper were degraded, with office paper showing maximum bioconversion at pH 7.0. The difference in the structural composition of the paper materials also affects the degree of saccharification, as the amount of sugar released from the various paper materials at optimum pH values is not similar. Together with other catalytic parameters, the pH value of this enzymatic catalysis is also to be considered when designing the development of waste paper as a bio-product resource, with limiting environmental pollution as an additional advantage of this process.
Afficher plus [+] Moins [-]Household Energy Fuel Choice in Nigeria Residential Urban Area
2023
Ubani, O. J. | Okosun, A. | Chukwurah, G. | Henry, Ivo
In most Nigerian cities, there have been an increased number of trading in charcoals, firewood, and sawdust. Yet, the fast citing of cooking gas refilling stations in these areas requires much to be studied since their increasing number suggests great demand for cooking gas. The knowledge of the different household fuel choices and the drivers of this choice was lacking in Nigerian cities, thus the inability of energy policymakers to predict and plan household fuel agenda in Nigeria. The thrust of this paper was to analyze the household energy fuel choice and the pattern of consumption as well as analyze the household socioeconomic factors that influenced the fuel choice in the Abakaliki urban area of Ebonyi State, Nigeria. Stratified and simple random sampling was adopted in the study. Regression was used to consider the relationship between energy fuel choice and household socioeconomic factors. It was revealed that there was a mixture of traditional and modern energy fuel choices in the study area, with the modern energy fuel choices (gas and electricity) having higher patronage. There was a significant relationship between energy fuel choice and household socioeconomic factors. It was recommended, among others, that a clear energy fuel policy that will adopt the identified explorable household socioeconomic factors that influence the choice of energy fuel be developed.
Afficher plus [+] Moins [-]Pattern of Lead Accumulation in Two Vegetable Plants Due to EDTA Treatment
2023
Rosyidah, A.
Phytoextraction and phytostabilization are the most consistent patterns or mechanisms of action of phytoremediation. One of the elements influencing the mechanism of action of heavy metal absorption by plant species is Ethylene Diamine Tetraacetic Acid (EDTA). Therefore, this study aimed to determine the pattern of phytoremediation in water spinach and spinach due to the addition of EDTA in the soil. The treatments tested by factor 1 were water spinach (T1) and spinach (T2), and factor 2 was the concentration of EDTA consisting of 3 levels, 0, 3, and 6 g/polybag. Each treatment was repeated three times on five sample plants. Furthermore, growth evaluation was carried out in the first six days after planting and conducted every 3 days. It was carried out on variables such as changes in plant height, leaves area, total root length, Pb content in the soil, fresh and dry weight of shoots and roots, shoot, seeds, and Translocation Factor (TF). The results showed that water spinach and spinach had different mechanisms of action due to the application of EDTA in Pb-contaminated media. Furthermore, water spinach and spinach have a mechanism of phytoextraction and phytostabilization, respectively. Therefore, spinach is safer than water spinach when grown in Pb-polluted land.
Afficher plus [+] Moins [-]Wastewater Treatment Technologies Selection Using Analytical Hierarchy Process and VIKOR Methods: A Case Study
2023
Sasikumar, Gnanasekaran | Sivasangari, A. | Ravibabu, S.
Due to the ever-increasing water scarcity problem across the globe, the treatment of wastewater is an important public health and socio-economic issue. Treating wastewater through proper technology is vital to protect the ecosystem from unsafe and contaminated matter available in wastewater. Identification of suitable wastewater treatment technologies is a complex Multi-Criteria Decision Making (MCDM) problem since it includes many conflicting assessment criteria. The objective of the paper is to construct an integrated model using the Analytical Hierarchy Process (AHP) and VIseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR) for evaluating wastewater treatment technologies (WWTTs). AHP is applied to calculate criteria weights, and the VIKOR method is applied to prioritize and select the best WWTTs. The proposed model is applied to selecting the best WWTT among four alternatives and seven criteria. It is found that the proposed model yields better results when compared with other MCDM solutions.
Afficher plus [+] Moins [-]The Impact of Climate Change on the City of Padang, Indonesia
2023
Prarikeslan, Widya | Sudiar, Nofi Yendri | Anugrah, Gema | Beri, Deski | Handayani, Dezi | Eka Putri, Irma Leilani | Gautama, Mohammad Isa
The impact of global warming is climate change which affects elements of society. This condition causes a decrease in the level of community welfare and increases the level of community vulnerability. Some climate change impacts are floods, droughts, landslides, and shoreline changes. In this study, we will focus on landslides. Landslides are among the most dangerous natural disasters that often occur in mountainous areas, especially during the rainy season. Various factors influence events involving landslides. This study aims to utilize GIS to identify landslide-prone areas in Padang. The method used in this study is the Zuidam and Concelado criteria overlay method for the level of landslide hazard and the broken method (jenks). The natural break (jenks) classification method reduces within-class variation and maximizes between-class variation. This study shows that the level of landslide vulnerability in Padang City is low, with a total area of 288854.38173 ha with a percentage of 42.21%. We need to consider more factors and experiment with training and validating data in more detail to gain insight into the physical contributions of the factors to landslide occurrences.
Afficher plus [+] Moins [-]Carbon Emission and Industrial Structure Adjustment in the Yellow River Basin of China: Based on the LMDI Decomposition Model
2023
Song, J. | Du, W. J. | Wang, F.
In the context of promoting high-quality development in the Yellow River Basin (YRB) of China, urgent action is needed to achieve the “Dual Carbon” goal through energy savings, emission reductions, and industrial upgrading. This study measures carbon emissions from eight types of energy consumption across 43 industries from 2000 to 2019. Using the Kaya-LMDI model, factors affecting carbon emissions are analyzed, and the relationship between industrial structure and carbon emissions is explored through the coefficient of variation (CV). The findings reveal that coal consumption remains significantly higher than other energy sources, and the effect of energy structure adjustment on carbon emission reduction is limited compared to the impact of energy consumption increase on carbon emission growth. Moreover, the economic output effect is identified as the primary driving factor of carbon emissions, while energy utilization rate is crucial in achieving energy savings and emission reductions. Finally, the CV of carbon emissions across 43 industries is increasing. Based on these results, we suggest several policy recommendations, including prioritizing ecological concerns, developing comprehensive and scientifically sound plans, optimizing energy consumption structure, improving energy utilization efficiency, and adjusting industrial structure to promote sustainable development in the YRB.
Afficher plus [+] Moins [-]Risk Perception of Healthcare Workers Regarding Polymer Medical Waste Management
2023
Kaur, Jasneet | Upendra, Sheela | Barde, Shital
Despite the relatively small amounts produced, medical waste is a significant issue for the government and the healthcare industry primarily because it poses threats to persons and the environment. Healthcare wastes pose threats to the environment and public health, but knowledge of these concerns and how they relate to management techniques is still lacking. Evaluating waste management practices and healthcare staff expertise is critical to identify shortcomings and lower risk levels. The study was conducted at three selected private hospitals. These three hospitals contain 462 beds, all together with 184 healthcare workers. The study was designed as a descriptive cross-sectional study, and three private healthcare institutions in the study region were evaluated. These 100 healthcare workers were chosen by purposive sampling. The hospitals under consideration include general surgical, Gynecological, pediatric, and various specialty treatments. Data was gathered for the study utilizing a quantitative questionnaire, which includes closed-ended structured questionnaires. The results showed that most healthcare workers practice waste segregation at source. Chemical cross-linking was very poor. However, waste shredding technology is being used substantially. Risk perception among Healthcare workers regarding polymer help waste management showed more of average to high risk. The study concluded that despite the existence of policies and plans, execution is still subpar at private healthcare institutions. The creation of guidelines for hospital waste management, their distribution to other institutions, and their encouragement to do a critical self-evaluation should all be required by the government.
Afficher plus [+] Moins [-]Analysis of teleconnection between the Arctic Oscillation and South American cryosphere reduction
2019 | 2023
Bolaño Ortiz, Tomás Rafael | Pascual Flores, Romina María | López Noreña, Ana Isabel | Ruggeri, María Florencia | Lakkis, Susan Gabriela | Puliafito, Salvador E.
Abstract: The cryosphere in South America is a very important resource because it is the main source of water for 85 million inhabitants distributed in Colombia, Ecuador, Peru, Bolivia, Chile and Argentina [1-2]. To know the effects due to global phenomena such as arctic oscillation (AO) in the reduction of the cryosphere in this region, we proceeded to analyze sources of reanalysis information (ERA-40; NCEP/NCAR Reanalysis) and high resolution snow cover (MOD10 500m) from Moderate-Resolution Imaging Spectroradiometer (MODIS). Several linear adjustments were made to observe how snow cover variations (Y) responded to variations in AO (X1 ), surface temperature (X2 ) and snow precipitation (X3 ).
Afficher plus [+] Moins [-]Evaluation of Lipase from an Indigenous Isolated Bacillus Strain for Biodiesel Production
2023
Neha, Nisha Sethi, Sangita Yadav, Subhash Chander, Sweta Kumari, Ankur and Asha Gupta
Lipases are utilized in biodiesel production utilizing various types of substrates. The use of lipase in bioenergy production aims to reduce energy crises and environmental pollution. Lipase-producing indigenous bacteria Bacillus licheniformis (Accession no. OP56979) and Bacillus rugosus (Accession no. OP56980) were isolated from various oil-contaminated sites. The isolated potential lipolytic bacteria were screened for maximum lipase production. Then, the bacteria showing the highest lipolytic activity were subjected to identification using the 16s rRNA technique while other isolated were identified biochemically. Lipase [LipBL-WII(c)] from Bacillus licheniformis having the highest lipolytic activity expressed various characteristics. Characterization of crude LipBL-WII(c) expressed that it showed stability in a wide range of pH (4 to 10) with optimum lipolytic activity observed at pH 8. It was then found to be active at a temperature range from 20°C to 80°C with optimal at 50°C. Lipase activity was also stimulated in metal ions such as Ca+1, Mg2+, and Zn2+ the most. Furthermore, LipBL-WII(c) retained lipolytic activity in the presence of various organic solvents and surfactants. The kinetic parameters (Km and Vmax) for LipBL-WII(c) were ascertained using Lineweaver- Burk plot. LipBL-WII(c) showed a potential for biodiesel production using olive oil as a source. Lipase gave 84% yield of biodiesel production from olive oil. Thus, it could be employed as a potential candidate for green biodiesel production using oil sources.
Afficher plus [+] Moins [-]Postnatal Exposure to A Low Dose of Imidacloprid: Oxidative Stress in Brain Without Affecting Learning and Behavior in Swiss Albino Mice
2023
A. Sharma, S. Gupta and M. Kaur
The neurotoxic effects of exposure to low levels of the pesticide imidacloprid (IMI) and the effect of curcumin are of current interest when exposure occurs during early development. Male weanlings of Swiss albino mice (21 days old) were given 1 mg.kg-1 body weight (1/130 of LD50 and 2 mg.kg-1 body weight (1/65 of LD50) of imidacloprid and Curcumin (100 mg/kg body wt.) by oral gavage from postnatal day 21 to postnatal day 60. Young adult offspring were studied for behavioral parameters and learning ability using open field and Morris water maze. After completing the behavioral test, brains were processed for acetylcholine esterase activity and antioxidant enzyme estimation. The level of lipid peroxidation and activity of catalase, superoxide dismutase, and glutathione were assayed. In the present study, parameters such as locomotor activities and cognitive skills were not affected compared to lower doses of imidacloprid in the open field and Morris water test. However, activities and levels of antioxidant enzymes such as catalase and lipid peroxidation were found to be altered. In contrast, superoxide dismutase, acetylcholine esterase activity, and glutathione remained unchanged compared to the control. This suggests that subchronic exposure to low doses of IMI can lead to significant alterations in the enzymes of antioxidant protective systems such as catalase and lipid peroxidation. Co-treatment with curcumin was able to restore the activities of the affected enzymes in comparison with the control.
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