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Hydrogen Sulfide Oxidizing Microbiome in Biogas-Stream Fed Biofilter in Palm Oil Factory
2024
Siriorn Boonyawanich, Peerada Prommeenate, Sukunya Oaew, Nipon Pisutpaisal and Saowaluck Haosagul
Hydrogen sulfide (H2S) is highly corrosive to electric generators, which is the main problem of biogas utilization. The industrial scale of the biofilter system relies on the performance of sulfide-oxidizing bacteria (SOB) via the activity of sulfur oxidation (soxABXYZ) and flavocytochrome sulfide dehydrogenase (fccAB) enzymes to reduce to a concentration below 100 ppm before using in industrial machinery. The main purpose of this research is to investigate the SOB community in full-scale H2S removal and their gene expression (fccAB and soxABXYZ) associated with H2S elimination efficiency. In this study, SOB communities were obtained from 2 sampling sites of the full-scale biofilter of palm oil factory (PPG), comprising starting sludge (PPG1) and recirculating sludge (PPG2). The abundance of SOB strains was examined by next-generation sequencing analysis (NGS) based on the 16S rRNA gene. The changes in the expression of genes involved in sulfur oxidation, namely soxABXYZ, and fccAB, between the 2 sampling sites were evaluated by using a comparative genomic hybridization (CGH) microarray. The results indicate that the high abundance of SOB genera that could play a vital role in biofilters belonged mainly to Sulfurovum, Paracoccus, Acidihalobacter, Acidithiobacillus, Thioalkalispira, Thiofaba, Caldisericum, Bacillus, were rapidly increased in the biofilter tank. Interestingly, expressions of soxAXYZ gene cluster at PPG2 were increased in Paracoccus pantotrophus J40 and Paracoccus alkenifer DSM 11593 for 1.1188 and 1.0518-fold, respectively, while in Acidihalobacter prosperus F5, the expression of fccAB genes was up to 1.3704 fold in comparison with PPG1. Increasing both relative abundance and gene expressions at PPG2 were correlated with 95% H2S removal efficiency. Hence, stabilization of the SOB microbiome is vital to H2S removal in industrial-scale biogas applications.
Mostrar más [+] Menos [-]Surface Runoff Estimation Using SCS-CN Method for Kurumballi Sub-watershed in Shivamogga District, Karnataka, India
2024
Govindaraju, T. Y. Vinutha, C. J. Rakesh, S. Lokanath and A. Kishor Kumar
SCS-curve number (CN) is one of the most well-liked and commonly applied methods for estimating surface runoff. The present study aims to calculate surface runoff using SCS-CN watershed-based calculation and geospatial technology in the Kurumballi sub-watershed Shivamogga District of Karnataka, India. The study area covers about an area of 47.67 sq. km. The union of land use/land cover classification with hydrological soil groups (HSG) yields the runoff estimation by the SCS-CN curve approach. This method calculates the runoff volume from the land surface flows into the river or streams. Moreover, the study area’s delineation of runoff potential zones was done using the thematic integration method. Different thematic layers were used, including lithology, geomorphology, soil, slope, land use and land cover, drainage, surface water bodies, groundwater contour, and isohyetal maps. Furthermore, associating it with the SCS-CN technique, the total surface runoff volume of the study area was estimated. The total surface runoff volume in the study area is 21065849.7 m3. To this study, thematic integration with the SCS-CN approach to estimate runoff for watersheds is valuable for improving water management and soil conservation.
Mostrar más [+] Menos [-]Detection of Sulfur Oxidizing Bacteria to Oxidize Hydrogen Sulfide in Biogas from Pig Farm by NGS and DNA Microarray Technique
2024
Siriorn Boonyawanich, Peerada Prommeenate, Sukunya Oaew, Wantanasak Suksong, Nipon Pisutpaisal and Saowaluck Haosagul
A high concentration of hydrogen sulfide (H2S) released from pig farming is one of the major environmental problems affecting surrounding communities. In modern pig farms, the bioscrubber is used to eliminate H2S, which is found to be driven mainly by the sulfur-oxidizing bacteria (SOB) community. Therefore, in this study, molecular biology techniques such as next-generation sequencing (NGS) and DNA microarray are proposed to study the linkage between enzyme activity and the abundance of the SOB community. The starting sludge (SFP1) and recirculating sludge (SFP2) samples were collected from the bioscrubber reactor in the pig farm. The abundance of microbial populations between the two sampling sites was considered together with the gene expression results of both soxABXYZ and fccAB. Based on the NGS analysis, the members of phylum Proteobacteria such as Halothiobacillus, Acidithiobacillus, Thiothrix, Novosphingobium, Sulfuricurvum, Sulfurovum, Sulfurimonas, Acinetobacter, Thiobacillus, Magnetospirillum, Arcobacter, and Paracoccus were predominantly found in SFP2. The presence of Cyanobacteria in SFP pig farms is associated with increased biogas yields. The microarray results showed that the expression of soxAXBYZ and fccAB genes involved in the oxidation of sulfide to sulfate was increased in Halothiobacillus, Paracoccus, Acidithiobacillus, Magnetospirillum, Sphingobium, Thiobacillus, Sulfuricurvum, Sulfuricurvum, Arcobacter, and Thiothrix. Both NGS and DNA microarray data supported the functional roles of SOB in odor elimination and the oxidation of H2S through the function of soxABXYZ and fccAB. The results also identified the key microbes for H2S odor treatment, which can be utilized to monitor the stability of biological treatment systems and the toxicity of sulfide minerals by oxidation.
Mostrar más [+] Menos [-]Temperature-related Saccharification of Delignified Sawdust Materials from the Lagos Lagoon in Nigeria
2024
J. B. M. Seeletse, N. A. Ndukwe and J. P. H. van Wyk
Sawdust, a product of the forest industry is mostly left untreated as solid waste. This phenomenon is well observed along the Lagos Lagoon in Nigeria where hundreds of trees are cut daily by sawmills to deliver wood for mainly the furniture industry. Different types of trees are utilized in this manner and the massive amounts of sawdust produced as a result of these activities are polluting the environment causing health risks for humans and animals. Cellulose, a glucose bio-polymer is a major structural component of sawdust and could be developed as a renewable energy resource should the cellulose be degraded into glucose, a fermentable sugar. This saccharification was done with Aspergillus niger cellulase and to make the cellulose more susceptible for cellulase action the sawdust was delignified with hydrogen peroxide. Both delignified and non-delignified sawdust were treated with the cellulase enzyme at incubation temperatures of 30°C, 40°C, 50°C, and 60°C. Delignification proved to be effective as an increased amount of sugar was released from all delignified sawdust materials relative to the non-delignified materials when saccharified with A. niger cellulase. Most of the materials were degraded at an incubation temperature of 40°C and 50°C and the highest percentage saccharification of 58% was obtained during the degradation of delignifed cellulose from the tree, Ricindendron heudelotti
Mostrar más [+] Menos [-]Transforming Energy Access: The Role of Micro Solar Dome in Providing Clean Energy Lighting in Rural India
2024
R. Karthik, Ramya Ranjan Behera, Uday Shankar, Priyadarshi Patnaik and Rudra Prakash Pradhan
Access to affordable and reliable energy sources can substantially enhance the lives of marginalized communities in rural areas. Unfortunately, numerous households in these communities rely upon unclean sources of energy such as kerosene to light the house even during daylight. To address this issue, solar off-grid technology - Micro Solar Dome (MSD) was implemented in various states across India, specifically benefiting the scheduled caste and scheduled tribe communities. The study, across the eight selected states, highlights the advantages of adopting off-grid technologies and their roles in promoting awareness of renewable energy solutions. The survey used purposive sampling to collect community members’ perceptions of the product’s benefits and their awareness of renewable technologies. The results indicated that the utilization of the product not only enhanced illumination levels within households but also contributed to improved safety, increased study hours for children, and facilitated economic activities during the evening hours. Furthermore, the study revealed that education plays a crucial role in adopting solar energy. However, interventions such as awareness programs and hands-on experiences with the products can also greatly enhance awareness and promote adoption in rural areas. Overall, the study provided compelling evidence of the significant and positive impact that small-scale initiatives like the MSD can have on the lives of marginalized communities. It also emphasized the potential of such solutions to empower these communities and improve their overall well-being.
Mostrar más [+] Menos [-]Alternate Chemical Compounds as a Condensation Nucleus in Cloud Seeding
2024
Hasan M. Azeez, Nagham T. Ibraheem and Hazim H. Hussain
Cloud seeding involves boosting precipitation by releasing substances into the air that act as cloud condensation or ice nuclei. These substances encourage the development of clouds and precipitation. It’s like giving Mother Nature a gentle push to assist with rainfall in specific areas. The current work aimed to suggest Al2O3 as an alternate compound in cloud seeding rather than silver iodide. In this research, a unique approach is used to identify condensation nuclei, which play a crucial role in cloud formation and droplet growth. Various samples and four sources were included in the current study; refrigerated helfa powder, Himalayan salt, generator powder, and pollen, were analyzed using different physicochemical instruments. The proportions of chemical compounds in the samples show that there is 1.392% of Al2O3 in Refrigerated helfa which is the highest than in the other 3 sources, while the proportions of elements in the samples indicate that refrigerated helfa contains the lowest toxic compound, and although Al2O3 is insoluble in water, it is hygroscopic and can absorb 6.4% of humidity within 24 hours. As for the surface tension, refrigerated helfa shows lower density and surface tension than the other three sources with values of 0.9480 and 47.89 respectively. Al2O3 shows high humid absorptivity and refrigerated helfa can be used as a main source for Al2O3 which has a low effect on biota and is recommended for use in cloud seeding. However further work is recommended to be carried out in using Al2O3 as an alternative compound to silver iodide in cloud seeding.
Mostrar más [+] Menos [-]Effects of Rainfall Intensity, Kinetic Energy and Slope Angle to the Upslope, Downslope, and Lateral Slope Components of Splash Erosion in Hillslope Agriculture: A Case in Badiangan, Ajuy, Iloilo
2024
Shevanee Ruth G. dela Cruz and Ricardo L. Fornis
This study was conducted in Barangay Badiangan, Ajuy, Iloilo City, Philippines (11°10’N, 122°58’E) to determine the effects of rainfall intensity and other rainfall-derived parameters on the directional components of splash erosion in hillslopes. There are five experimental set-ups with slope angles ranging from 0% to 48% were tested under natural rainfall conditions using a modified splash collector. The data collected shows that kinetic energy, slope, and rainfall intensity have shown significant effects on splash erosion. The models obtained using regression analysis are 𝑄𝑄𝑑𝑑𝑑𝑑𝑑𝑑=0.0093(𝐾𝐾𝐾𝐾0.80) and 𝑄𝑄𝑡 𝑡𝑡𝑡𝑡𝑡𝑡𝑡𝑡=0.060(𝐾𝐾𝐾𝐾0.107)(𝑆𝑆0.700)(𝐼𝐼200.700) . The model equation performance has been validated using the Standard Error of Estimates with values of 12 and 9.4 for splash detachment and splash transport, respectively. The constants used for kinetic energy in detachment and slope in transport align with the research by Quansah (1981) for sandy soil, which is similar (the characteristics) to the soil at our research site. Additionally, rainfall intensity, especially with a 20-min duration, generated the best model as it yielded the lowest SEE value for all cases.
Mostrar más [+] Menos [-]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.
Mostrar más [+] Menos [-]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.
Mostrar más [+] Menos [-]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.
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