Article
Engineering, Environmental
M. Danouche, A. Bounaga, R. Boulif, Y. Zeroual, R. Benhida, K. Lyamlouli
Summary: Phosphogypsum (PG) generated during phosphoric acid production contains a significant amount of sulfate, which can be biologically converted into sulfide. This study focuses on selecting and evaluating microbial consortia from sulfate-rich environments for the initial step of sulfur recovery. The MYC-consortium isolated from a hydrothermal niche showed the highest reduction capacity and performance under various conditions. This research provides insights into the potential of the MYC-consortium in converting sulfate from PG into sulfide, which is a critical step in sulfur biorecovery.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Environmental Sciences
Guang Guo, Chong Liu, Jiuxiao Hao, Fang Tian, Keqiang Ding, Can Zhang, Feng Yang, Tingfeng Liu, Jin Xu, Zhengbing Guan
Summary: A halo-thermophilic bacterial consortium capable of decolorizing azo dye under high salinity and temperature conditions was enriched in this study, with Bacillus identified as the dominant genus playing a key role in the decolorization process. The consortium demonstrated effectiveness in decolorization of metanil yellow G across a wide range of pH values, temperatures, dye concentrations, and salinities. Additionally, various enzymes such as laccase, manganese peroxidase, lignin peroxidase, and azoreductase were found to be involved in the decolorization process, with a proposed pathway for decolorization based on GC-MS and FTIR results.
Article
Environmental Sciences
G. Koulini, A. R. Laiju, S. T. Ramesh, R. Gandhimathi, P. Nidheesh
Summary: The study demonstrates that the electro-peroxone (EP) process is effective in degrading dyes and exhibits high efficiency in decolorization and organic carbon removal in real textile effluent, offering a cost-effective and environmentally friendly solution.
Article
Chemistry, Multidisciplinary
Han-Qing Zhao, Wen-Qiang Li, Nannan Hou, Lei Li, Yiran Wang, Peili Lu, Yang Mu
Summary: In this study, nitrogen-doped graphene (NG) was found to significantly accelerate the decolorization of methyl orange (MO) azo dye by sulfide. The stagnant time of MO decolorization was remarkably reduced in the presence of NGs, particularly those with graphitic nitrogen. Doping nitrogen improved the electron conductivity and enhanced the interactions between sulfide and carbon atoms bonded to graphitic nitrogen, leading to the formation of reactive intermediate polysulfides.
CHINESE CHEMICAL LETTERS
(2023)
Article
Biotechnology & Applied Microbiology
Roselin Neihsial, Ningombam Anjana Singha, Arvind Kumar Singh
Summary: This study reports the degradation activity of a bacterial consortium developed in the azo dye medium for multiple azo dye degradation, with most effective degradation observed under static condition. Analysis of the bacterial community revealed the presence of Proteobacteria, Bacteroidetes, and Firmicutes as dominant phyla. Genes predicted from metagenomic sequences were mapped onto the KEGG pathway to construct the Congo Red degradation pathway.
INTERNATIONAL BIODETERIORATION & BIODEGRADATION
(2022)
Article
Environmental Sciences
Shantkriti Srinivasan, Paul Olusegun Bankole, Senthil Kumar Sadasivam
Summary: This study investigated the decolorization efficiency of selective reactive azo dyes by non-adapted Lysinibacillus sphaericus MTCC 9523 in optimized conditions, with visual color changes and spectroscopic analysis confirming decolorization. HPLC analysis showed differences in retention time between control and treated samples, supporting biodegradation, while GC-MS analysis revealed the chemical identities of metabolites and predicted the metabolic pathways of degradation for each dye. Overall, the use of adapted and non-adapted microbes is a promising, cost-effective and time-saving green strategy for the biodegradation of textile effluent containing azo dyes.
FRONTIERS IN ENVIRONMENTAL SCIENCE
(2022)
Article
Chemistry, Analytical
Carrie Cockerham, Ashton Caruthers, Jeremy McCloud, Laura M. Fortner, Sungmin Youn, Sean P. McBride
Summary: Challenges exist in wastewater treatment of dyes from the textiles industry. A study shows that functionalized membranes can effectively remove dyes and ions with high rejection rates.
Article
Environmental Sciences
T. Yilmaz, M. Yildiz, C. S. Arzum Yapici, H. U. Annak, D. Ucar
Summary: In this study, sulfidogenic up flow anaerobic reactors were used to treat textile wastewater, and Remazol Brilliant Violet 5R was used as a model dyestuff. The results showed that the reactors could efficiently remove the dye, but an increase in dye concentration resulted in a decrease in sulfate reduction and COD oxidation. Batch reactors demonstrated that biogenic sulfide produced in sulfate reduction could degrade Remazol Brilliant Violet 5R, and the presence of microorganisms increased the reduction rate.
INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCE AND TECHNOLOGY
(2023)
Article
Engineering, Environmental
Ruixiang Li, Tian Li, Yuxuan Wan, Xiaolin Zhang, Xueyi Liu, Runtong Li, Hangming Pu, Tong Gao, Xin Wang, Qixing Zhou
Summary: Azo dye pollution is a global issue with current treatment methods falling short of emission standards. Microbial electrochemical systems show promise for decolorization, with electrode modification offering a method to enhance performance. Modification with polyaniline and graphene led to the highest decolorization efficiency, attributed to altered metabolic pathways facilitating extracellular electron transfer.
JOURNAL OF HAZARDOUS MATERIALS
(2022)
Article
Microbiology
Aalfin-Emmanuel Santhanarajan, Chaeyoung Rhee, Woo Jun Sul, Keunje Yoo, Hoon Je Seong, Hong-Gi Kim, Sung-Cheol Koh
Summary: This study investigated the biodegradation of the azo dye AB113 and identified the key pathways and enzymes involved in its degradation. The results showed that the benzoate and naphthalene degradation pathways played a crucial role in AB113 degradation, and enzymes such as NADH quinone oxidoreductase, N-acetyltransferase, aromatic ring-hydroxylating dioxygenase, and CYP450 were found to be important for AB113 degradation.
Article
Green & Sustainable Science & Technology
Neha Garg, Anurag Garg, Suparna Mukherji
Summary: In this study, the removal of the recalcitrant azo dye reactive yellow 145 (RY145) was achieved through sequential treatment using zero valent aluminum (ZVAl) and bacterial degradation. The ZVAl pretreatment resulted in significant decolorization, followed by microbial degradation of the intermediates. The combined treatment exhibited high efficiency in dye decolorization and organic compound degradation, addressing the challenges posed by RY145.
JOURNAL OF CLEANER PRODUCTION
(2022)
Article
Engineering, Chemical
Marta Mendes, Irina S. Moreira, Patricia Moreira, Manuela Pintado, Paula M. L. Castro
Summary: A yeast-bioaugmented aerobic granular sludge (AGS) system was developed using a sequencing batch reactor (SBR) inoculated with activated sludge and a dye-decolorizing yeast strain-Yarrowia lipolytica (HOMOGST27AB). The AGS-SBR system effectively removed carbon and nitrogen from synthetic saline wastewater, without being affected by the reactive textile dye addition. Successful bioaugmentation with Y. lipolytica (HOMOGST27AB) was confirmed through sequencing analysis of granule samples throughout the reactor operation. The microbial profile of the AGS core microbiome showed a dynamic composition, with shifts in abundance of different bacterial phyla during different phases of the bioreactor operation.
Article
Biochemistry & Molecular Biology
Thi Quynh Hoa Kieu, Thi Yen Nguyen, Chi Linh Do
Summary: A wastewater treatment system utilizing sulfate-reducing and sulfide-oxidizing processes was developed for organic wastewater with high sulfate/sulfide content. The study investigated the impacts of COD/SO42- ratio and hydraulic retention time (HRT) on the removal efficiencies of sulfate, COD, sulfide, and electricity generation. The results showed stable COD and sulfate removal efficiencies of 94.8±0.6% and 93.0±1.3% during the 63-day continuous operation. A power density level of 18.0±1.6 mW/m2 was achieved with a sulfide removal efficiency of 93.0±1.2%. However, sulfide removal efficiency and power density gradually decreased after 45 days, potentially due to sulfur accumulation on the anode.
Article
Environmental Sciences
Leena Merlin Biju, V Pooshana, P. Senthil Kumar, K. Veena Gayathri, Sabah Ansar, Saravanan Govindaraju
Summary: This study examined the removal of mixed azo dyes and Cr(VI) metal in synthetic textile wastewater using haloalkaliphilic bacterial strains in a Moving Bed Biofilm Reactor. The results showed efficient decolorization of dyes and degradation of the metal, even at higher concentrations, by the eco-friendly bacterial consortium. Molecular and morphological characterization of the bacterial strains, along with analysis of metabolites, supported the findings of hazardous pollutant degradation and simultaneous dye decolorization.
Article
Engineering, Environmental
Tianwei Hao
Summary: This study investigated the response and adaptation mechanisms of granular and flocculent sulfate-reducing bacteria (SRB) sludge to acidic metal-laden wastewater (AMW). The results showed that the flocculent SRB lost more than 50% of their treatment capacity, while the granular SRB maintained a high metal removal rate throughout the trial. The stability of the granular structure and microbial activity was found to be influenced by the extracellular glycosyl compositions.
Article
Agricultural Engineering
Mingjing He, Xiefei Zhu, Shanta Dutta, Samir Kumar Khanal, Keat Teong Lee, Ondrej Masek, Daniel C. W. Tsang
Summary: Hydrothermal carbonization (HTC) is a promising alternative for valorizing food waste digestate (FWD) and avoiding disposal issues. Co-HTC of FWD with wet lignocellulosic biomass, such as wet yard waste (YW), and 0.5 M HCl shows superior attributes in terms of energy recovery and nutrient recovery from process water. However, attention should be paid to the carbon loss issue during the process.
BIORESOURCE TECHNOLOGY
(2022)
Article
Agricultural Engineering
Ianny Andrade Cruz, Wachiranon Chuenchart, Fei Long, K. C. Surendra, Larissa Renata Santos Andrade, Muhammad Bilal, Hong Liu, Renan Tavares Figueiredo, Samir Kumar Khanal, Luiz Fernando Romanholo Ferreira
Summary: This review critically examines the application of machine learning in the anaerobic digestion process, focusing on evaluating important algorithms and their applications in AD modeling, and outlining the challenges faced by ML in this context.
BIORESOURCE TECHNOLOGY
(2022)
Article
Engineering, Environmental
Sumeth Wongkiew, Chongrak Polprasert, Thammarat Koottatep, Tawan Limpiyakorn, K. C. Surendra, Samir Kumar Khanal
Summary: The study found that adding acetic acid in a bioponic system negatively affected plant yield but did not have a significant impact on nitrogen and phosphorus concentrations. It is recommended to control the acetic acid concentration below 500 mg/L or extend the loading interval to improve the operation of bioponics systems based on chicken manure and digestate.
Article
Engineering, Environmental
Qian Zeng, Feixiang Zan, Tianwei Hao, Samir Kumar Khanal, Guanghao Chen
Summary: Research on shifting biogas to VFA production for higher economic gains has led to the discovery that electrochemical pretreatment (EPT) can efficiently produce VFA during anaerobic sludge digestion, reducing the dependence on chemicals.
Article
Agricultural Engineering
K. C. Surendra, Irini Angelidaki, Samir Kumar Khanal
Summary: Mitigating greenhouse gas (GHG) emissions is a major focus of the global agreement, The Glasgow Climate Pact. Industrial and agro-waste contribute significantly to global GHG emissions, and if timely measures are not taken, the waste sector's GHG emissions are likely to worsen due to population growth, affluence, and urbanization. Efforts are being made to shift from conventional waste treatment to resource recovery, adopting a circular bio-economy concept. Technologies such as anaerobic digestion, composting, pyrolysis, algae farming, and microbial fuel cells have advanced resource recovery from organic wastes. This virtual special issue (VSI) contains 25 manuscripts covering various aspects of waste and biomass valorization, providing valuable resources for researchers in the field.
BIORESOURCE TECHNOLOGY
(2022)
Article
Environmental Sciences
Satja Aksorn, Vorapot Kanokkantapong, Chongrak Polprasert, Pongsak (Lek) Noophan, Samir Kumar Khanal, Sumeth Wongkiew
Summary: The study showed that under Cu and Zn supplemented bioponics, pak choi had higher bioconcentration factors for Cu and Zn compared to lettuce, and the root microbial community was significantly affected. However, according to the health risk assessment by the US EPA, consumption of bioponic vegetables containing Cu and Zn does not pose long-term health risks for children or adults.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2022)
Review
Biotechnology & Applied Microbiology
Sharareh Harirchi, Steven Wainaina, Taner Sar, Seyed Ali Nojoumi, Milad Parchami, Mohsen Parchami, Sunita Varjani, Samir Kumar Khanal, Jonathan Wong, Mukesh Kumar Awasthi, Mohammad J. Taherzadeh
Summary: This review comprehensively analyzes the interactions and influences of different microorganisms in anaerobic digestion process, and discusses the latest applications and challenges of AD in the production of novel bio-products.
Article
Agronomy
Yiping Guo, Xiangkai Tao, Weiyong Zhu, Yapeng Ji, K. C. Surendra, Samir Kumar Khanal, Bingtao Liu, Guoting Li
Summary: Biochar is commonly used as a material to improve soil properties, but its application conditions can influence the adsorption of heavy metal copper. This study found that a specific combination of biochar, wheat straw, and cow manure compost could greatly enhance the adsorption rate of copper in soil. The adsorption processes were identified as multiphase diffusion processes, and the interactions between copper and soil were mainly monolayer adsorption with other complex reactions. However, in leaching experiments, the addition of wheat straw and compost led to more copper being dissolved in the leaching water.
COMMUNICATIONS IN SOIL SCIENCE AND PLANT ANALYSIS
(2023)
Review
Agricultural Engineering
Muzammil Khan, Wachiranon Chuenchart, K. C. Surendra, Samir Kumar Khanal
Summary: Anaerobic co-digestion (AcoD) offers various advantages in terms of better digestibility, process stability, and increased methane yield. However, the efficient operation of an AcoD system requires a comprehensive understanding of important operational parameters and monitoring processes can be tedious. Artificial intelligence (AI) has emerged as an innovative approach to optimize and control the AcoD process. This review discusses the applications of AI in AcoD process optimization, control, prediction, and real-time monitoring, as well as the comparison of different AI algorithms.
BIORESOURCE TECHNOLOGY
(2023)
Review
Environmental Sciences
Kyle Rafael Marcelino, Li Ling, Sumeth Wongkiew, Hua Thai Nhan, K. C. Surendra, Ty Shitanaka, Hui Lu, Samir Kumar Khanal
Summary: There has been increasing interest in nanobubble technology due to its unique physicochemical properties, which have potential applications in environmental engineering and agriculture. The use of nanobubbles can inactivate pathogens in water treatment, remove harmful microorganisms on food, and remove pollutants from wastewater. Nanobubbles also have the potential to increase the dissolved oxygen level and plant yields. However, the fundamental mechanisms and mass transfer performance of nanobubble technology are not well understood.
CRITICAL REVIEWS IN ENVIRONMENTAL SCIENCE AND TECHNOLOGY
(2023)
Article
Engineering, Environmental
Mingde Ji, Jie Wang, Samir Kumar Khanal, Saqi Wang, Jian Zhang, Shuang Liang, Huijun Xie, Haiming Wu, Zhen Hu
Summary: In this study, a high-rate activated sludge-two-stage vertical up-flow constructed wetland (HRAS-TVUCW) system was developed to reduce carbon emissions during municipal wastewater treatment. The carbon emissions of the HRAS-TVUCW system were 4.1-fold lower than that of the conventional anaerobic/anoxic/aerobic (A2O) process, while the recovered energy from the HRAS-TVUCW system increased its contribution to carbon neutrality by 4.6-fold. Functional microbial community analysis showed that the controlled dissolved oxygen allocation in the HRAS-TVUCW system led to distinct microbial communities in each unit, facilitating denitrification efficiency increase and carbon emissions reduction. Overall, the HRAS-TVUCW system can be considered as a cost-effective and sustainable low-carbon technology for municipal wastewater treatment.
Editorial Material
Energy & Fuels
Ayon Tarafdar, Sunita Varjani, Samir Khanal, Siming You, Ashok Pandey
BIOENERGY RESEARCH
(2023)
Editorial Material
Agricultural Engineering
Samir Kumar Khanal, Ayon Tarafdar, Siming You
Summary: In recent years, there has been significant attention towards the digital transformation of bioprocesses, focusing on interconnectivity, online monitoring, process automation, AI and ML, and real-time data acquisition. AI can analyze and forecast high-dimensional data from bioprocess dynamics, allowing for precise control and synchronization to improve performance and efficiency. Data-driven bioprocessing is a promising technology for addressing challenges in bioprocesses. The MLSB-2022 special issue incorporates recent advances in ML and AI applications in bioprocesses, providing valuable resources for researchers to learn major developments.
BIORESOURCE TECHNOLOGY
(2023)
Article
Environmental Sciences
Xuezhi Wang, Zhongfang Lei, Zhenya Zhang, Kazuya Shimizu, Duu-Jong Lee, Samir Kumar Khanal
Summary: In this study, the use of nanobubble water (NBW) as a bio-augmentation agent in high-solids anaerobic digestion (AD) of corn straw was investigated. The results showed that NBW bio-augmentation significantly increased methane production and achieved a net energy gain and energy recovery, providing a sustainable management solution for renewable energy production from agricultural wastes.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Environmental Sciences
Sumeth Wongkiew, Chongrak Polprasert, Pongsak (Lek) Noophan, Thammarat Koottatep, Vorapot Kanokkantapong, K. C. Surendra, Samir Kumar Khanal
Summary: Food waste can be combined with bioponics to enhance nutrient availability. Adding vermicompost leachate (VCL) improves the co-composting of organic waste and the biodegradation of organic compounds. This study demonstrates that food waste provides nitrogen and phosphorus for lettuce growth, and VCL addition increases nutrient levels in bioponics.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2023)
