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Enhanced Phenanthrene Biodegradation by Bacillus brevis Using Response Surface Methodology
2024
Kiran Bishnoi, Pushpa Rani and Narsi R. Bishnoi
The current investigation assessed the capability of a well-adapted and enriched bacterial strain known as Bacillus brevis for the biodegradation of phenanthrene. To enhance the removal efficiency of phenanthrene, employed Response Surface Methodology (RSM) in conjunction with a Box-Behnken design (BBD) model. The experiments were designed to explore the impact of pH (6.0 to 9.0), temperature (20 to 40°C), initial phenanthrene concentration (50 and 100 ppm), and incubation time (7 to 21 days) on biodegradation of phenanthrene. The highest level of phenanthrene biodegradation, approximately 55.0%, was achieved by Bacillus brevis when the optimal conditions were met as pH of 7.0, temperature 30oC, and initial phenanthrene concentration (70 ppm) after 21 days of incubation time. This study underscores the significance of employing statistical tools like RSM to enhance the microbial degradation of contaminants.
显示更多 [+] 显示较少 [-]Exploring the Adsorption Efficiency of Local Apricot Seed Shell as a Sustainable Sorbent for Nitrate Ion
2024
Mohd Ishaq, R. C. Chhipa, Anupama Sharma, Gh. Ali and Riyaz-ul Hussain
Locally available apricot seed shell as agro-waste was used for the preparation of adsorbents. The biochar was prepared at 370°C via pyrolysis and 80 mesh particle sizes were modified by 1N HCl. Nitrate adsorption and effect of co-ions from aqueous solution were studied under batch model using apricot seed shell powder (ASSP), apricot seed shell biochar (ASSB), and activated apricot seed shell biochar (AASSB). FTIR and pHPZC measurements were used to characterize the adsorbents. Based on the experimental findings, the optimum conditions follow pH 2, 0.3g dosage, initial concentration of 50 mg.L-1, and contact time of 90 min. The three forms of adsorbent exhibited good adsorption for nitrate. However, the maximum percentage removal of nitrate ions from the aqueous solution followed the order AASSB>ASSB>ASSP. The adsorption kinetic of nitrate ion was best fitted by pseudo 2nd order, and the parameters of adsorption isotherms elucidated favorable and improved sorption. This agro-waste could be used to develop sustainable adsorbents in water and wastewater treatment methods and has great potential to replace commercially available sorbents.
显示更多 [+] 显示较少 [-]Carbon Dioxide Adsorption by Variation in Operating Parameters of Sound Assisted Fluidization Using Coal Based Fine Activated Carbon
2024
A. P. Ganorkar and A. M. Langde
This research delves into the promising domain of CO2 capture through fine solid activated carbon adsorbent, offering a more energy-efficient alternative to traditional adsorption methods. The central challenge addressed here is the utility of cheaper CO2 adsorbent, fine powder materials whose properties can be precisely tailored via molecular-level fictionalization. Equally vital is selecting an optimal fluidizing column configuration that maximizes CO2 interaction with adsorption particles and enhances adsorption efficiency. The proposed solution is a fluidized bed column uniquely equipped with integrated acoustic vibrations to counteract interparticle forces common in fine powders. For adsorption evaluations, sound-assisted fluidized-bed experimentation on a laboratory size was set up. Adsorbent material activated carbon made up of coal underwent rigorous testing between a range of 20 Hz-200 Hz and 20 dB-135 dB. Results reveal the beneficial effects of acoustic enhancement of fluidization quality and adsorption efficiency, increased adsorption capacity, enhanced bed utilization, and accelerated adsorption rates. Extensive research has been conducted on the detailed effects of major operational variables on adsorption performance, notably frequency, sound intensity, and minimum fluidization velocity. The findings highlight the pivotal role of particle size with mean size 75 microns range as a determinant of adsorption capacity at 100 Hz and 125 dB. At the end of experimentation, the adsorbent considered for the experiment is compared to the study adsorption capacity at operating conditions. The research concludes with a discussion on the effects of influencing parameters for adsorption on employing sound vibrations using fluidization technique adsorption for CO2 capture.
显示更多 [+] 显示较少 [-]Research Insights into Punjab’s Stubble Burning Menace
2024
Ruchi Kohli, Anu Mittal and Amit Mittal
The current investigation endeavors to evaluate the prevalence of stubble burning in India, with a special focus on the state of Punjab. The study emphasizes the enormity of stubble burning by examining farm fire incidents, pollutant emissions, its detrimental impacts. It supports the effective management of crop residue along with proposing alternatives to stubble burning. The article conveys the message that stubble burning can result in deleterious effects on the environment, human health, crop growth, natural ecosystems, visibility, and physical infrastructure. The key solutions lie in education, functional literacy, a heightened awareness of environmental laws, rights and duties, stringent governance, and socially responsible public, promoting adherence to the National Green Tribunal’s guidelines for managing crop residue and enlightening farmers about the ill effects of stubble burning on animal, soil, human health, crop biodiversity, and climate change. The available data of districts of Punjab indicates the recent waning trend in stubble burning, thus heralding a positive indication of environmental preservation. Decreased stubble burning is the reward of untiring government initiatives, support and subsidies, awareness programs, advanced research and technology, and enforcement of stringent regulations combined with recognition of the deleterious environmental impacts of stubble burning. This research article indicates that there is still a need for efforts to be made to eliminate stubble burning altogether.
显示更多 [+] 显示较少 [-]Microbes Breaking Down Plastic: Insights for Sustainable Waste Management
2024
C. J. Patel, R. H. Kansagara, D. V. Modi, N. J. Dudhat, K. H. Sojitra and D. M. Babaria
This research investigates the microbial degradation of low-density polyethylene (LDPE) and high-density polyethylene (HDPE) plastics by Bacillus sp., Proteus sp., Pseudomonas sp., and Salmonella sp. The study employs a systematic approach, isolating microorganisms from plastic-contaminated soil and subjecting them to a series of biochemical tests for identification. The research evaluates the weight loss of LDPE and HDPE over two months, revealing varying degrees of degradation among the bacterial strains. Results suggest a potential greater susceptibility of HDPE to microbial degradation. Scanning Electron Microscopy (SEM) analysis provides high-resolution images of the plastic surface, indicating structural changes and biofilm formation during degradation. The findings highlight the unique enzymatic capabilities of each strain and underscore the significance of SEM in elucidating microbial interactions with plastics. The study prompts discussions on optimization, synergistic effects, and the identification of key enzymes in plastic degradation, emphasizing the importance of microbial strategies for waste management. Overall, this research contributes valuable insights into the potential of bacterial strains for addressing plastic pollution challenges.
显示更多 [+] 显示较少 [-]Performance Evaluation of Advanced Wastewater Treatment Technologies in Herbal Processing and Extraction Industry
2024
Avinash Kumar Sharda, Varinder S. Kanwar and Ashok Sharma
Due to enormous quantities with hazards and complexity in nature is a big challenge for effective treatment of wastewater from pharmaceutical processes including herbal extraction through conventional methods of distillation. The situation is further aggravated in countries facing high rising population, urbanization, and industrialization resulting in the generation of industrial wastes. The study has been carried out in the herbal extraction industry by conducting stage-wise sampling of ETP based on the conventional method and further coupled with ozonation as an advanced treatment to comply with regulatory standards. Additionally, the same process was studied that implementing the best available technology (BAT) by providing ETP with advanced technology modules such as MBR (membrane bioreactor) + RO + O3 has not only resulted in compliance with standards but also reuse of treated wastewater into the process and utilities has been proved to be techno-economically a viable and sustainable option. Modifying existing aeration tanks and advanced oxidation through ozone injection post-biological treatment has resulted in COD and BOD reduction of 96.42% and 99.0% respectively. Whereas in the case of MBR + RO + O3, the values of pH, BOD, COD, TSS, and sulfide have been observed as 8.32, 2.0 mg.L-1, 14.0 mg.L-1, 1.0 mg.L-1 and 0.0 mg.L-1 respectively and 98% recovery of treated effluent, thus saving 44 KL.day-1 of freshwater resulting into significant financial benefits of Rupees 12.59 acs annually, which otherwise was outsourced through tankers.
显示更多 [+] 显示较少 [-]Characteristics, Abundance and Polymer Type of Microplastics in Anadara granosa (Blood Clam) from Coastal Area of Palopo City
2024
Abd. Gafur Rahman, Muhammad Farid Samawi and Shinta Werorilangi
Plastic waste in marine waters will undergo a degradation process that breaks down large plastic pieces into smaller particles called microplastics. The abundance of microplastics, caused by their small size (<5mm) can be easily indirectly consumed by aquatic animals. Anadara granosa is one of the bivalves that is quite vulnerable to microplastic contamination because it has the nature of a filter feeder which means it can sift particles and organic matter around it. The purpose of this study was to determine the characteristics, abundance, and types of microplastic polymers in blood clams (A. granosa). The results of microplastic observations made on 60 blood clams were 153 microplastic particles identified from 47 individuals (78%) of contaminated blood clams with an average microplastic abundance of 0.591 ± 0.083 item/gr. Fiber-type microplastics are the most dominant form found and blue is the most dominant color found in the sample. Based on the average abundance of microplastics in Anadara granosa in the coastal area of Palopo City, it is lower than several studies that have been conducted previously. Fourier Transform-Infra Red was conducted to determine the type of polymer in microplastics. Three types of polymers were found in the Anadara granosa samples polyethylene terephthalate (PET), polystyrene, and polyester. The three types of polymers have effects on human health such as respiratory problems, skin irritation, and genotoxicity. Action is needed to prevent microplastic pollution in Palopo City’s rivers before microplastic pollution becomes more severe in the future.
显示更多 [+] 显示较少 [-]Novel Bacterial Consortium for Mitigation of Odor and Enhance Compost Maturation Rate of Municipal Solid Waste: A Step Toward a Greener Economy
2024
P.A.K.C. Wijerathna, K.P.P. Udayagee, F.S. Idroos and Pathmalal M. Manage
Composting is an integral component of sustainable Municipal Solid Waste (MSW) management within the circular bio-economy platform. However, it faces challenges due to malodorous emissions that impact environmental and societal equilibrium. The present study aims to minimize odorous emissions and expedite compost maturation using a novel, efficient microbial consortium. Bacteria sourced from open dump sites in Sri Lanka were carefully screened based on concurrent enzyme production. Five developed consortia were tested for their performance in reducing malodors during the composting process of MSW. Consortium No. 5 (C5), comprised of Bacillus haynesii, Bacillus amyloliquefaciens, and Bacillus safensis, demonstrated outstanding performance with a significant (p < 0.05) reduction in odorous emissions. Additionally, consortium C5 exhibited impressive control over gas emissions, maintaining VOC, CH4, NH3, and H2S concentrations within ranges of 0.5-6 ppm, 0.5-0.8 ppm, 0.3-0.5 ppm, and 0.5-0.6 ppm, respectively, compared to control concentrations of 4.5-10.2 ppm, 0.5-5.5 ppm, 0.3-5.5 ppm, and 0.5-6.4 ppm, respectively. Additionally, comprehensive Electronic nose (E-nose) analysis substantiated C5’s efficiency in attenuating Methane-Aliphatic compounds, Sulfur and Aromatic compounds, along with low-polarity aromatic and alkane compounds, all with statistical significance (p < 0.05). Further, the developed consortium could reduce the composting time from 110 ± 10 days to 17 ± 3 days, offering a sustainable solution for global MSW management.
显示更多 [+] 显示较少 [-]Bioaccumulation of Lead (Pb) and Cadmium (Cd) in Padina Australis Hauck at Palang Beach, Tuban, East Java, Indonesia
2024
F. Rachmadiarti, Winarsih, H. Fitrihidajati, T. Purnomo, S. Kuntjoro, F. A. Nafidiastri, R. Yolanda, R. Ambarwati, D. Anggorowati, W. Budijastuti, U. Faizah, D. Putriarti and N. F. Rosyidah
Waters polluted with Pb and Cd have a negative impact on the environment. Padina australis grows abundantly on the coast of Palang Subdistrict, Tuban, and the local community consumes it. Macroalgae as food must be free of metal contamination. This study aims to determine the impact of Pb and Cd bioaccumulation on P. australis. Sampling was conducted at two stations, including Station I, Panyuran Village, and Station II, Glodog Village. Analysis of Pb and Cd metal levels using Atomic Absorption Spectrophotometry (AAS). Analysis of protein content using the Kjeldahl method. The data obtained was analyzed with Principle Component Analysis (PCA). The results of the analysis of Pb and Cd levels in P. australis at station II, which are 0.200 ± 0.028 and 0.021 ± 0.004 mg.kg-1 higher than station I, which are 0.194 ± 0.015 and 0.010 ± 0.001 mg.kg-1. The protein content of P. australis at station I was 4.713 ± 0.508 mg.kg-1, and at station II was 5.900 ± 0.928 mg.kg-1. This shows that P. australis is still considered good for consumption even though it has been polluted and contains Pb and Cd metals. P. australis can tolerate and does not experience severe physiological damage so it has the potential as a heavy metal phytoremediator.
显示更多 [+] 显示较少 [-]Potential of Heavy Metals and Microplastics Contamination in River Mpanga, Fort Portal, Kabarole District, Uganda
2024
C. Nyakoojo, W. Kabiswa, E. Najjuma, P. Matovu and H. Ocaya
Anthropogenic environmental pollution is a major development challenge in Ugandan rivers and lakes, the key drivers being industrialization, agriculture, and urbanization. The aim of the study was to assess the potential of heavy metal and microplastic contamination in River Mpanga, Fort Portal, Uganda. Triplicate water and sediment samples were collected from three sampling sites, preserved, and analyzed at the Chemistry Department, Makerere University for heavy metals, while microplastics analysis was conducted at NaFIRRI, Jinja. Sediment heavy metal contamination was assessed from the geoaccumulation index, while microplastic characterization and quantification were determined from stereomicroscopy and morphological features. Arsenic was the most prevalent metal with a mean concentration of 13.2 ppm thus higher than permissible maximum limits of WHO. The mean concentrations (ppm) of copper, lead, and cadmium were 0.01, 0.01, and 0.001 respectively, and below the permissible maximum. Sediment samples revealed very strong arsenic contamination, strong contamination for copper, moderate to strong contamination for lead, and a potential lack of contamination for cadmium. The higher concentrations of the heavy metals in the sediments compared to water could be attributed to bioaccumulation, as evidenced by the high geoaccumulation values. Microplastics occurred throughout the river and included fragments, filaments, film, pellets, form, and fibers. The presence of heavy metals and microplastics was attributed to anthropogenic activities within the river vicinity, which discharged heavy metal-laden waste into River Mpanga. High arsenic concentrations and sediment accumulation of contaminants pose serious potential public health threats to the local communities.
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