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This review explores recent progress in sequencing batch reactors (SBRs) and hybrid systems for wastewater treatment, emphasizing their adaptability and effectiveness in managing diverse wastewater compositions. Through extensive literature analysis from 1985 to 2024, the integration of advanced technologies like photocatalysis within hybrid systems is highlighted, showing promise for improved pollutant removal efficiencies. Insights into operational parameters, reactor design, and microbial communities influencing SBR performance are discussed. Sequencing batch biofilm reactors (SBBRs) demonstrate exceptional efficiency in Chemical Oxygen Demand, nitrogen, and phosphorus removal, while innovative anaerobic-aerobic-anoxic sequencing batch reactors (AOA-SBRs) offer effective nutrient removal strategies. Hybrid systems, particularly photocatalytic sequencing batch reactors (PSBRs), show potential for removing persistent pollutants like antibiotics and phenols, underscoring the significance of advanced oxidation processes. However, research gaps persist, including the need for comparative studies between different SBR types and comprehensive evaluations of long-term performance, environmental variability, and economic viability. Addressing these gaps will be vital for the practical deployment of SBRs and hybrid systems. Further exploration of synergies, economic considerations, and reactor stability will enhance the sustainability and scalability of these technologies for efficient and eco-friendly wastewater treatment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

The global transition towards clean and sustainable energy sources has led to an increasing interest in green hydrogen production. The present work focuses on the development and assessment of a solar-assisted green hydrogen production system. The basic objective of this work is to investigate the influence of solar radiation to drive the electrolysis process for green hydrogen production. The system design includes photovoltaic solar panel to capture solar radiation and convert it into electrical energy. This energy is further utilized to operate an electrolyzer with zinc electrodes that facilitates the water-splitting reaction resulting in the production of hydrogen gas. The solar panel outputs along with global radiation and other relevant climatic conditions are monitored. The hydrogen production is analyzed at three different voltages, i.e., 11 V, 12 V, and 13 V. After 60 min of operations, the maximum amount of hydrogen (2952 mL) is produced at 13 V. The fabricated electrolyzer has been found suitable and economically feasible., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Herein, we investigated the impact of polymorphism vs. dimension control of titania nanocrystals towards hydrogen generation. Two different forms of titania nanoparticles have been synthesized following the solvothermal method, leading to the formation of two distinct physicochemical features. Detailed structural, morphological, and optical studies revealed that the formation of titania nanorods correspond to rutile while granular particles correspond to the anatase phase. Among various titania polymorphs, anatase is well known for its superior photocatalytic activity; however, to our surprise, the as-synthesized rutile nanorods exhibited higher catalytic activity in comparison to anatase spheres, and hydrogen evolution was considerably enhanced after the addition of a minute amount of Pt as the co-catalyst. Thus, despite the higher catalytic activity of anatase, the enhanced hydrogen evolution of rutile nanorods may be related to the creation of a 1D structure. Our study highlights the importance of considering not only TiO 2 polymorphism but also shape and dimension in optimizing photocatalytic H 2 production., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The main aim of this study is to experimentally investigate the yield of extraction and the presence of wax in the extracted yield from Musaacuminata (banana) biomass based on various functional groups that are present in natural wax. Extraction of natural wax from Musaacuminata (banana) biomass has been done by using the Soxhlet apparatus method in the presence of both polar (ethyl acetate and ethanol) and non-polar (toluene and hexane) solvents. The extracted yield has been found as 3.58% from hexane, 5.16% from toluene, 7.03% from ethyl acetate, and 10.26% from ethanol. The wax was also found in the extracted yield only in the case of nonpolar solvents (toluene and hexane). The novelty of this work is that Musaacuminata (banana) waste biomass has been utilized to recover the natural wax using nonpolar solvents and also compared with that of polar solvents to check the scope of wax extraction using polar solvents. Also, statistical analysis has been performed of the extracted yield using both solvents. Thin Layer Chromatography (TLC) and Fourier Transform Infrared Spectroscopy (FTIR) methods have been used to determine the various hydrocarbon chains present in the extracted yield which is similar to that of natural wax., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest that could have appeared to influence the work reported in this paper. This paper contains no studies with human or animal subjects., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Potassium, a pivotal macronutrient essential for growth, development, and crop yield, serves as a critical determinant of soil productivity. Its depletion disrupts the equilibrium of soil nutrients, prompting an investigation into integrated potassium management strategies to address this challenge. A field experiment was conducted during the winter season of 2020 using a randomized complete block design, with eight treatments, each replicated three times in Chinese cabbage ( Brassica rapa L. subsp. chinensis ). These treatments comprised standard (100 %) and reduced (75 % and 50 %) rates of the recommended dose of potassium (RDK) via muriate of potash (MOP). Variations in the inclusion and exclusion of plant growth-promoting rhizobacteria (PGPR), farmyard manure (FYM) as 25 % of the potassium recommendation, and foliar spray of nano potash were systematically implemented. Findings unequivocally demonstrated that the treatmentT 8 , involving 100 % RDK +25 % K through FYM + PGPR + nano K fertilizer spray at 25 and 40 DAS, yielded significant improvements in both green fodder (64.0 t ha -1 ) and dry fodder (7.87 t ha -1 ).Moreover, T 8 exhibited the highest values for total ash (8.75 %), total ash yield (68.9 ± 2.88 kg ha -1 ), ether extract (2.85 %), ether extract yield (22.4 ± 0.88 kg ha -1 ), crude protein (9.71 %), and total crude protein yield (76.4 ± 3.21 kg ha -1 ). Conversely, a marked reduction was observed in various fiber components and carbohydrate fractions upon application of the T 8 treatment. The lowest values of yield, crude protein content, total ash ether extract were recorded in treatment T 1 (control) applied with no potassium. This investigation underscores the inadequacy of the recommended potassium dose in achieving optimal productivity, necessitating a re-evaluation of potassium fertilization levels. The integrated approach involving FYM, PGPR, and nano potash, coupled with the recommended potassium dose through MOP, emerges as a promising avenue for augmenting both yield and quality parameters in Chinese cabbage., Competing Interests: Authors declare that there is no conflict of interest., (© 2024 The Authors.)

The interest in algae-derived bioactive compounds has grown due to their potential therapeutic efficacy against a range of diseases. These compounds, derived from proteins, exhibit diverse functions and profound pharmacological effects. Recent research has highlighted the extensive health benefits of algae-derived bioactive compounds, positioning them as potential natural antioxidants in the food, pharmaceutical, and cosmetic industries. This study focuses on extracting proteins from Porphyra yezoensis using innovative physical pre-treatment methods such as stirring, ball milling, and homogenization, under various acidic and alkaline conditions. Enzymatic hydrolysis, employing commercial enzymes at optimal temperature, pH, and enzyme-substrate ratios, produced distinct fractions according to molecular weight. Pepsin demonstrated the highest hydrolysis rate, with the fraction above 10 kDa identified as the most bioactive hydrolysate. Antioxidant activity was evaluated through DPPH, ABTS, ferrous ion chelation, and reducing power assays, demonstrating high antioxidant potential and the ability to mitigate oxidative stress. The 10 kDa fraction of pepsin hydrolysate exhibited 82.6% DPPH activity, 77.5% ABTS activity, 88.4% ferrous ion chelation activity, and higher reducing power potential (0.84 absorbance at 700 nm). Further exploration of mechanisms, amino acid profiles, and potential in vivo benefits is essential to fully exploit the medicinal potential of these algae-derived hydrolysates., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest., (© Association of Food Scientists & Technologists (India) 2024. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

The significance of integrating agricultural by-products such as paddy husk ash (PHA) and potato peels with organic fertilizers lies in enhancing soil fertility, increasing crop yields, and reducing reliance on traditional organic fertilizers like farmyard manure (FYM) or compost alone. Grounded in sustainable agriculture and nutrient management frameworks, this study examines the impact of diverse formulations derived from agricultural waste on productivity, nutrient efficiency, and profitability in a pigeon pea-vegetable mustard-okra cropping system. A two-year field experiment (2020-2022) at ICAR-IARI, New Delhi tested seven nutrient sources viz., (T 1 ) control, (T 2 ) 100% RDN through FYM, (T 3 ) 100% RDN through improved RRC, (T 4 ) 100% RDN through PHA based formulation, (T 5 ) 75% RDN through PHA based formulation, (T 6 ) 100% RDN through PPC based formulation and (T 7 ) 75% RDN through PPC based formulation that were tested in RBD and replicated thrice. Treatment T 4 had significant effect on seed yield of pigeon pea (1.89 ± 0.09 and 1.97 ± 0.12 t ha -1 ), leaf yield of vegetable mustard (81.57 ± 4.59 and 82.97 ± 4.17 t ha -1 ), and fruit yield of okra (13.54 ± 0.82 and 13.78 ± 0.81 t ha -1 ) grown in rotation, followed by treatment T 6 and T 2 during both the years respectively over control. Enhanced system uptake of N, P and K along with system gross and net returns in T 4 , showed increases of 78.9%, 83.8%, 72.4%, 54.4% and 56.8% in the first year and 77.5%, 80.8%, 77.7%, 54.8% and 57.4% in the second year, respectively, over control. Treatment T 4 significantly improved apparent recovery by 66.3% and 69.2% in pigeon pea, 64.7% and 47.9% in vegetable mustard, and 72.7% and 79.4% in okra over T 3 , averaged across two years. Based on the above findings, (T 4 ) 100% RDN through PHA-based formulation, and (T 6 ) 100% RDN through PPC-based formulation can be recommended for areas with a shortage of FYM but availability of rice husk ash/potato peels for sustainable agricultural wastes and improved sustainability., Competing Interests: Declaration of competing interest Authors declare that there is no conflict of interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Solar drying is a renewable energy-based technique which is widely used for food preservation purpose. In this study, various drying characteristics of the solar-dried Solanum tuberosum samples of different thicknesses have been investigated at variable climate condition of Lucknow. A mathematical model has also been developed to validate experimental results to predict the drying rate, free moisture content, and other parameters. Pre-treatment of the food samples was also done before the experimental runs on the fabricated solar dryer. Global radiation has also been monitored during the study to correlate the heat transfer rate in inner and outer sides of the solar drying chamber. SEM analysis has also been done to analyze the surface morphology of solar-dried samples. All solar dried food samples have uniformly heated. There was no hot-spot condition present on the surface of the samples. The drying efficiency and payback period of the fabricated solar dryer have also been calculated as 22.9% and 1.42 years, respectively. Model data have been found in good agreement with the experimental data within a 5% error. This modified model can be used for different agro-based food materials such as carrot, kiwifruit, and yam., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The main aim of this study is to evaluate the performance of a single slope solar still and to assess the effect of nanofluid on its performance. A single basin single slope solar still was designed and fabricated at the Department of Chemical Engineering, IET Lucknow. Its performance was assessed in terms of the yield of potable water. The effect of various climatic parameters was also studied. Al 2 O 3 nanofluid was used to enhance the yield of the solar still. In the presence of nanofluid, the total yield of the solar still improved by 16.6%. Its economic feasibility was analyzed and reported. The portability of the small size of solar stills, its better economics, easy fabrication, and good performance make them very useful for industrial as well as household purposes., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The present study investigated the removal of malachite green dye from aquifers by means of microalgae-derived mesoporous diatom biosilica. The various process variables (dye concentration, pH, and adsorbent dose) influencing the removal of the dye were optimized and their interactive effects on the removal efficiency were explored by response surface methodology. The pH of the solution (pH = 5.26) was found to be the most dominating among other tested variables. The Langmuir isotherm (R 2  = 0.995) best fitted the equilibrium adsorption data with an adsorption capacity of 40.7 mg/g at 323 K and pseudo-second-order model (R 2  = 0.983) best elucidated the rate of dye removal (10.6 mg/g). The underlying mechanism of adsorption was investigated by Weber-Morris and Boyd models and results revealed that the film diffusion governed the overall adsorption process. The theoretical investigations on the dye structure using DFT-based chemical reactivity descriptors indicated that malachite green cations are electrophilic, reactive and possess the ability to accept electrons, and are strongly adsorbed on the surface of diatom biosilica. Also, the Fukui function analysis proposed the favorable adsorption sites available on the adsorbent surface., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

In this study, the thermal and drying characteristics of a thin layer food sample were investigated. An indirect type, simple, efficient, and economically feasible solar dryer was fabricated and used for food preservation. However, a dynamic model of a fabricated solar dryer was also presented to gain a better insight into the drying and thermal actions. This model consists of thermal modeling of the drying chamber, solar collector, and solar-dried food sample. The law of conservation of energy was applied to evaluate the temperature at different sections of the solar dryer with respect to drying time. All listed model equations were solved in the MATLAB environment. This study helps to examine the influence of solar radiation on the collector plate temperature, drying chamber temperature, food sample temperature, and performance parameters such as thermal efficiency with respect to drying time. Model data was found in good agreement with experimental data within a 4% error. It is concluded that the drying of food material is affected by air temperature, the collector temperature, mode of heat transfer, and material characteristics such as dimension and mass of the food sample., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Prolonged and excessive use of chlorpyrifos (CPS) has caused severe pollution, particularly in crops, vegetables, fruits, and water sources. As a result, CPS is detected in various food and water samples using conventional methods. However, its applications are limited due to size, portability, cost, etc. In this regard, electrochemical sensors are preferred for CPS detection due to their high sensitivity, reliability, rapid, on-site detection, and user-friendly. Notably, graphene-based electrochemical sensors have gained more attention due to their unique physiochemical and electrochemical properties. It shows high sensitivity, selectivity, and quick response because of its high surface area and high conductivity. In this review, we have discussed an overview of three graphene-based different functional electrochemical sensors such as electroanalytical sensors, bio-electrochemical sensors, and photoelectrochemical sensors used to detect CPS in food and water samples. Furthermore, the fabrication and operation of these electrochemical sensors using various materials (low band gap material, nanomaterials, enzymes, antibodies, DNA, aptamers, and so on) and electrochemical techniques (CV, DPV, EIS, SWV etc.) are discussed. The study found that the electrical signal was reduced with increasing CPS concentration. This is due to the blocking of active sites, reduced redox reaction, impedance, irreversible reactions, etc. In addition, acetylcholinesterase-coupled sensors are more sensitive and stable than others. Also, it can be further improved by fabricating with low band gap nanomaterials. Despite their advantages, these sensors have significant drawbacks, such as low reusability, repeatability, stability, and high cost. Therefore, further research is required to overcome such limitations., Competing Interests: Conflict of interestThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this manuscript., (© Association of Food Scientists & Technologists (India) 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

The implementation of integrated potassium management presents a viable approach for augmenting plant growth, yield, and nutrient uptake while enhancing soil nutrient availability. A field experiment was executed during the rabi season of 2020, employing a randomized complete block design encompassing eight treatments involving standard (100%) and reduced (75% and 50%) rates of the recommended dose of potassium (RDK) administered through muriate of potash (MOP). Treatments included variations in the incorporation/exclusion of plant growth-promoting rhizobacteria (PGPR), farmyard manure (FYM) at 25% of potassium recommendation, and foliar application of nano potash. The use of 100% RDK +25% K augmentation through FYM + PGPR and nano K fertilizer spray at 25 and 40 DAS (T 8 ) exhibited significant enhancements in green fodder yield (64.0 ± 2.2 t ha -1 ) over control with no potassium application (47.3 ± 3.7 t ha -1 ) and found at par with and 75% RDK + 25% K augmentation through FYM + PGPR and nano K fertilizer spray at 25 and 40 DAS (T 7 ). These treatments yielded maximum percent increase for plant height (34.9%), leaf count (38.5%), leaf dimensions (28.8-31.5%), stem girth (25.84%), root volume (27.0%), and root length (37.64%), observed at the harvest stage compared to control (T 1 -no potassium application). The treatment T 8 was on par with T 7 and recorded highest uptake of macro (N, P, and K) and micro (Zn, Fe, Cu, and Mn) nutrients. While soil parameters such as available nitrogen and potassium levels were notably increased through the application of treatment T 7 across various treatment combinations and found significantly superiority over treatment T 8 . Multivariate analysis also highlighted treatment T 7 is more efficient in maintaining sustainability. Hence, based on the present findings it can be concluded that application of 75% RDK +25% K augmentation through FYM + PGPR and nano K fertilizer spray at 25 and 40 DAS (T 7 ) can be recommended for achieving enhanced productivity and soil fertility improvement within agricultural systems., Competing Interests: Authors declare that there is no conflict of interest., (© 2024 Published by Elsevier Ltd.)

The escalating demand for long-chain polyunsaturated fatty acids (PUFAs) due to their vital health effects has deepened the exploration of sustainable sources. Thraustochytrium sp. stands out as a promising platform for omega-3 and 6 PUFA production. This research strategically optimizes key parameters: temperature, salinity, pH, and G:Y:P ratio and the optimized conditions for maximum biomass, total lipid, and DHA enhancement were 28 °C, 50 %, 6, and 10:1:2 respectively. Process optimization enhanced 32.30 and 31.92 % biomass (9.88 g/L) and lipid (6.57 g/L) yield. Notably, DHA concentration experienced a substantial rise of 69.91 % (1.63 g/L), accompanied by notable increases in EPA and DPA by 82.69 % and 31.47 %, respectively. MANOVA analysis underscored the statistical significance of the optimization process (p < 0.01), with all environmental factors significantly influencing biomass and lipid data (p < 0.05), particularly impacting DHA production. Thraustochytrium sp. can be a potential source of commercial DHA production with the fine-tuning of these key process parameters., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

In the past decade, the demand and interest of consumers have expanded for using plant-based novel starch sources in different food and non-food processing. Therefore, millet-based value-added functional foods are acquired spare attention due to their excellent nutritional, medicinal, and therapeutic properties. Millet is mainly composed of starch (amylose and amylopectin), which is primary component of the millet grain and defines the quality of millet-based food products. Millet contains approximately 70 % starch of the total grain, which can be used as a, ingredient, thickening agent, binding agent, and stabilizer commercially due to its functional attributes. The physical, chemical, and enzymatic methods are used to extract starch from millet and other cereals. Numerous ways, such as non-thermal physical processes, including ultrasonication, HPP (High pressure processing) high-pressure, PEF (Pulsed electric field), and irradiation are used for modification of millet starch and improve functional properties compared to native starch. In the present review, different databases such as Scopus, Google Scholar, Research Gate, Science Direct, Web of Science, and PubMed were used to collect research articles, review articles, book chapters, reports, etc., for detailed study about millet starch, their extraction (wet milling process) and modification methods such as physical, chemical, biological. The impact of different modification approaches on the techno-functional properties of millet starch and their applications in different sectors have also been reviewed. The data and information created and aggregated in this study will give users the necessary knowledge to further utilize millet starch for value addition and new product development., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 Published by Elsevier Ltd.)

Water is a fundamental requirement for the survival of human beings. Although water is abundantly available across the globe, access to freshwater still remains a major concern. Most of the water available is saline or brackish, which is not fit for human consumption. Desalination is the optimum solution for production of potable water from saline water. A major shortcoming of conventional desalination technologies is their dependence on fossil fuel that results in environmental degradation, global warming, etc. Therefore, sustainable desalination technology has evolved as a need of hour. Among all renewable energy resources, solar energy is abundantly available and can be potentially harvested. Therefore, solar energy can be used to drive sustainable desalination technologies. A solar still converts saline water into freshwater in a single step using solar energy. But the major drawbacks of solar still are relatively lower efficiency and lower yield. Nanofluids are widely used to overcome these limitations due to their extraordinary and unique properties. This paper critically reviews the recent research performed on the application of nanofluids in solar desalination systems. Methods of nanofluid preparation, their types and properties are also discussed in detail. Application of nanofluids in solar desalination systems is discussed with special attention on performance enhancement of solar stills. Combinations of nanofluids with various other performance enhancement techniques are also considered. The effectiveness of nanofluids in solar stills is found to be dependent majorly on the nature and concentration of the nanofluid used., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Microbial electrosynthesis (MES) presents a versatile approach for efficiently converting carbon dioxide (CO 2 ) into valuable products. However, poor electron uptake by the microorganisms from the cathode severely limits the performance of MES. In this study, a graphitic carbon nitride (g-C 3 N 4 )-metal-organic framework (MOF) i.e. HKUST-1 composite was newly designed and synthesized as the cathode catalyst for MES operations. The physiochemical analysis such as X-ray diffraction, scanning electron microscopy (SEM), and X-ray fluorescence spectroscopy showed the successful synthesis of g-C 3 N 4 -HKUST-1, whereas electrochemical assessments revealed its enhanced kinetics for redox reactions. The g-C 3 N 4 -HKUST-1 composite displayed excellent biocompatibility to develop electroactive biohybrid catalyst for CO 2 reduction. The MES with g-C 3 N 4 -HKUST-1 biohybrid demonstrated an excellent current uptake of 1.7 mA/cm 2 , which was noted higher as compared to the MES using g-C 3 N 4 biohybrid (1.1 mA/cm 2 ). Both the MESs could convert CO 2 into acetic and isobutyric acid with a significantly higher yield of 0.46 g/L.d and 0.14 g/L.d respectively in MES with g-C 3 N 4 -HKUST-1 biohybrid and 0.27 g/L.d and 0.06 g/L.d, respectively in MES with g-C 3 N 4 biohybrid. The findings of this study suggest that g-C 3 N 4 -HKUST-1 is a highly efficient catalytic material for biocathodes in MESs to significantly enhance the CO 2 conversion., (© 2023. The Author(s).)

We produced carbon-negative biochar from the pyrolysis of sawdust biomass alone (SB) and from the co-pyrolysis of sawdust and plastic waste (SPB). The co-pyrolysis approach in this study was driven by several hypothetical factors, such as increased porosity, surface chemistry, stability, as well as waste management. We applied pyrolyzed and co-pyrolyzed biochars for the removal of ciprofloxacin (CFX) and sulfamethoxazole (SMX). Due to its more alkaline and amorphous nature, SB showed better removal efficiencies compared to SPB. The maximum removals of CFX and SMX with SB were observed as ∼95% and >95%, respectively whereas with SPB were 58.8%, and 34.9%, respectively. The primary mechanisms involved in the adsorption process were H-bonding, electrostatic and π-π electron donor-acceptor interactions. Homogenously and heterogeneously driven adsorption of both antibiotics followed the pseudo-second-order kinetic model, implying electron sharing/transfer (chemisorption) mediated adsorption. The work is highly pertinent in the context of emerging concerns related to drivers that promote antimicrobial resistance., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

Proper waste disposal is a key towards sustainable development. Wastewater treatment is delineated by the application of efficient, economic and novel catalysts. Biochar is derived from the thermochemical conversion of biomass or any carbonaceous materials and is considered as one of the most eco-friendly substitute for activated carbon. Owing to its large surface area, porosity, crystallinity and active functional groups, the biochar-based catalysts has been extensively applied for the abatement of toxic pollutants from wastewater streams. While most of the reviews focus on the adsorptive properties of the biochar, this review critically analyses the recent development of biochar-based catalysts in the field of advanced oxidation processes (Fenton-like systems, photocatalytic and sonocatalytic systems). The presence of persistent free radicals and oxygen-containing functional groups renders biochar to act as catalyst. The mechanisms accompanying catalytic performance of biochar-based catalysts have also been reviewed. However, the research in this area is quite at an initial phase, and many advancements schemes are essential prior to scale-up and commercialization. Future researches should be devoted to more efficient and rigorous understanding of the structural properties of biochar to engineer the catalytic degradation of targeted pollutants in wastewater treatment., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest regarding the publication of this paper., (Copyright © 2022. Published by Elsevier B.V.)

Recent developments in biogas upgradation have opened new horizons for its utilisation because upgradation technologies are fully developed and commercially available. However, the implementation of biogas upgrading technologies is not at the scale required to harness the full potential of biogas. Therefore, it is requisite to adopt a multicriteria decision-making methodology (MCDM) to select the most appropriate biogas up-gradation technology as each technology has its own set of benefits and downside. In this multifaceted scenario, the analytical hierarchy Process (AHP), one of the most preferred MCDM methods in rational decision-making, is applied in this study to select the most appropriate biogas upgrading technology. The broader recognition of AHP is its provision for converting multifaceted problems into a simple hierarchy. The research results reveal that biogas up-gradation technologies based on water scrubbing and membrane separation rank first and second among the alternatives. This research will show a direction to researchers and the MCDM community involved in biogas upgradation technologies on a broader scale., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Biomass is present in ample amounts in rural areas, mainly in agriculture residue and animal wastes. Biogas can be produced from rural solid waste, providing affordable clean energy for rural households and a prominent solution to solid waste management. Despite having several benefits of using biogas, the contribution of biogas in rural areas is not as much as expected. Several technical and non-technical barriers are accountable for the slow rate of biogas technology adoption in rural households. Nineteen barriers to household biogas plant adoption in four dimensions of technical, economic, market, and awareness are identified and ranked with the analytical hierarchy process (AHP) in the perspective of rural India. The outcome of the barrier dimension reveals that the economic dimension gets the highest weight of (0.350), followed by the market with a weight of (0.322). At the same time, high installation cost with a weight of (0.141) dominates in the category of barriers, followed by competition from freely available fuel with a weight of 0.105). The gap in capital cost and capital subsidy, lack of paying capacity, and lack of easy credit have positioned respectively third, fourth, and fifth in the overall ranking of barriers with weights of (0.094), (0.084), and (0.08). This paper may contribute significantly to creating greater awareness, evaluating numerous barriers, and adopting biogas technology in India more effectively and efficiently., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The chemical composition of root exudates and root extracts from Chrysopogon zizanioides (L.) Roberty cv KS-1 was determined in the presence of lead [Pb(II)]. Hitherto, no information is available in the literature concerning the phytochemical components of root exudates of C. zizanioides. Significantly higher concentrations of total carbohydrates (26.75 and 42.62% in root exudates and root extract, respectively), reducing sugars (21.46 and 56.11% in root exudates and root extract, respectively), total proteins (9.22 and 23.70% in root exudates and root extract, respectively), total phenolic acids (14.69 and 8.33% in root exudates and root extract, respectively), total flavonoids (14.30 and 12.28% in root exudates and root extract, respectively), and total alkaloids (12.48 and 7.96% in root exudates and root extract, respectively) were observed in samples from plants growing under Pb(II) stress in comparison to the respective controls. GC-MS profiling showed the presence of a diverse group of compounds in root exudates and extracts, including terpenes, alkaloids, flavonoids, carotenoids, plant hormones, carboxylic/organic acids, and fatty acids. Among the detected compounds, many have an important role in plant development, regulating rhizosphere microbiota and allelopathy. Furthermore, the results indicated that C. zizanioides exudates possess a chemotactic response for rhizospheric bacterial strains Bacillus licheniformis, Bacillus subtilis, and Acinetobacter junii Pb1., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Microbial fuel cells (MFCs) are an emerging technology for converting organic waste into electricity, thus providing potential solution to energy crises along with eco-friendly wastewater treatment. The electrode properties and biocatalysts are the major factors affecting electricity production in MFC. The electrons generated during microbial metabolism are captured by the anode and transferred towards the cathode via an external circuit, causing the flow of electricity. This flow of electrons is greatly influenced by the electrode properties and thus, much effort has been made towards electrode modification to improve the MFC performance. Different semiconductors, nanostructured metal oxides and their composite materials have been used to modify the anode as they possess high specific surface area, good biocompatibility, chemical stability and conductive properties. The cathode materials have also been modified using metals like platinum and nano-composites for increasing the redox potential, electrical conductivity and surface area. Therefore, this paper reviews the recent developments in the modification of electrodes towards improving the power generation capacity of MFCs., (Copyright © 2021. Published by Elsevier Ltd.)

The discharge of effluents from the textile industry is a multidimensional problem that affects the ecosystem in many ways. Though many new technologies are being developed, it remains to be seen which of those can be practiced in a real scenario. The current investigation attempts to absorb the Malachite Green, an effluent from textile dye using Chinese Fan Palm Seed Biochar. Accordingly, biochar was prepared using fruits of Chinese Fan Palm (Livistona chinensis) tree. The fruit also yielded a significant amount of biochar and bio-oil. 1.346 kg of fresh and cleaned fruit was fast pyrolyzed at 500 °C in a laboratory-scale Pyrolyzer resulting in 0.487 kg of biochar and 0.803 L of bio-oil. The remaining fruit matter was converted to gaseous products. The kinetics of dye removal were studied and the parameters were determined. The study advocates that the Langmuir isotherm model simulates the adsorption experiment, to a good extent. From the plot, the maximum (monolayer) adsorption capacity, Q m was determined to be 21.4 mg/g. The suitability of the Langmuir isotherm model onto biochar was established by the high correlation coefficient, R 2 that was higher than 0.97., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Green macroalgae comprise significant amount of structural carbohydrates for their conversion to liquid biofuels. However, it generally relies on species characteristics and the variability in seasonal profile to determine its route for bioprocessing. Hence, this study was conducted to analyze the indigenous marine macroalgal strain (Ulva prolifera) with respect to periodic trend and reducing sugar extraction. Consequently, in our investigation, the monthly variation in sugar profile and bioethanol yield was assessed between the monsoon and post-monsoon seasons, of which relatively high reducing sugar and fermentative bioethanol yield of about 0.152 ± 0.009 g/gdw and 6.275 ± 0.161 g/L was obtained for the October-month isolate (MITM10). Thereafter, the biochemical profile of this collected biomass (MITM10) revealed carbohydrate 34.98 ± 3.30%, protein 12.45 ± 0.49%, and lipid 1.93 ± 0.07%, respectively, on dry weight basis. Of these, the total carbohydrate fraction yielded the maximum reducing sugar of 0.156 ± 0.005 g/gdw under optimal conditions (11.07% (w/v) dosage, 0.9 M H 2 SO 4 , 121°C for 50 min) for thermal-acid hydrolysis. Furthermore, the elimination of polysaccharides was confirmed using the characterization techniques scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) spectroscopy. Therefore, the present thermochemical treatment method provides a species-specific novel strategy to breakdown the macroalgal cell wall polysaccharides that enhances sugar extraction for its utilization as an efficient bioenergy resource., (© 2021. The Author(s).)

This paper demonstrates the fabrication of silk nanodisc (SND) dispersed chitosan (CS) based new edible coating as a candidate for superior thermal, hydrophobic, optical, mechanical, and physicochemical properties, which further provide remarkable storage quality for banana fruits. Fabrication of SND is attained following acid hydrolysis of silk fibroin (SF), where the successful nanostructures formulations are analyzed by FESEM, FETEM and XRD analysis delivering disc shaped morphology with amplified crystallinity (~95.0%). The SF has been fabricated from waste muga cocoons using the degumming process. The superior thermal stability of SND compared to SF portray a new era in required heat resistant packaging. The effectiveness of SND is investigated on packaging properties of CS biocomposites including thermal, wettability, mechanical, color, surface morphology, and others. Wettability of SND incorporated CS biocomposite enhanced by ~ 10° suggesting improved hydrophobicity. The edible coatings are a new candidate to improve the shelf life of bananas over 7 days at 25 °C for prevailing original weight, optical property, firmness, and others., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Aromatic hydrocarbons (AHCs) are one of the major environmental pollutants introduced from both natural and anthropogenic sources. Many AHCs are well known for their toxic, carcinogenic, and mutagenic impact on human health and ecological systems. Biodegradation is an eco-friendly and cost-effective option as microorganisms (e.g., bacteria, fungi, and algae) can efficiently breakdown or transform such pollutants into less harmful and simple metabolites (e.g., carbon dioxide (aerobic), methane (anaerobic), water, and inorganic salts). This paper is organized to offer a state-of-the-art review on the biodegradation of AHCs (monocyclic aromatic hydrocarbons (MAHs) and polycyclic aromatic hydrocarbons (PAHs)) and associated mechanisms. The recent progress in biological treatment using suspended and attached growth bioreactors for the biodegradation of AHCs is also discussed. In addition, various substrate growth and inhibition models are introduced along with the key factors governing their biodegradation kinetics. The growth and inhibition models have helped gain a better understanding of substrate inhibition in biodegradation. Techno-economic analysis (TEA) and life cycle assessment (LCA) aspects are also described to assess the technical, economical, and environmental impacts of the biological treatment system., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Application of agrochemicals in farming sector to control insects and pests; and use of synthetic organic dyes to color the products are increasing continuously due to the rapid growth of industries. During the application process many industries releases toxic agrochemicals and dyes in to the aquatic environment and on land without the proper treatment. Due to their toxicity the disposal of such chemicals is of utmost importance. Biochar offers the ability to remediate these substances from environmental matrices because of their high sorption ability of pollutants from water and soil. This review highlights the development and advancement of biochar-based treatment for abatement of agrochemicals and synthetic organic dyes, involving its technical aspects and the variables connected with removing these kinds of pollutants. Several optimization parameters like temperature, pH, chemical concentration, biochar properties, time, and co-existing ions have been elaborated. Literature survey shows that most of the researches on biochar application have been conducted in the batch mode. Hence there is an urgent need to apply this beneficial technique for the remediation of pollutants at the larger scale in the real water and soil samples. A comprehensive summary on sorption kinetics and adsorption isotherms with regards to pollutant removal is also presented. This review also covers the cost analysis of various techniques where biochar has been used as an adsorbent. Thus this review makes an easy roadmap for the further development in biochar and biochar based composites and expansion of these demanding areas of research in biochar and their applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021. Published by Elsevier Ltd.)

Antibiotic resistance is a global health emergency linked to unrestrained use of pharmaceutical and personal care products (PPCPs) as prophylactic agent and therapeutic purposes across various industries. Occurrence of pharmaceuticals are identified in ground water, surface water, soils, and wastewater treatment plants (WWTPs) in ng/L to μg/L concentration range. The prevalence of organic compounds including antimicrobial agents, hormones, antibiotics, preservatives, disinfectants, synthetic musks etc. in environment have posed serious health concerns. The aim of this review is to elucidate the major sources accountable for emergence of antibiotic resistance. For this purpose, variety of introductory sources and fate of PPCPs in aquatic environment including human and veterinary wastes, aquaculture and agriculture related wastes, and other anthropogenic activities have been discussed. Furthermore, genetic and enzymatic factors responsible for transfer and appearance of antibiotic resistance genes are presented. Ecotoxicity of PPCPs has been studied in environment in order to present risk imposed to human and ecological health. As per published literature reports, the removal of antibiotics and related traces being difficult, couples the possibility of emergence of antibiotic resistance and hence sustainability in global water resources. Therefore, research on environmental behavior and control strategies should be conducted along with assessing their chronic toxicity to identify potential human and ecological risks., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Continuous discharge and persistence of antibiotics in aquatic ecosystem is identified as emerging environment health hazard. Partial degradation and inappropriate disposal induce appearance of diverse antibiotic resistant genes (ARGs) and bacteria, hence their execution is imperative. Conventional methods including waste water treatment plants (WWTPs) are found ineffective for the removal of recalcitrant antibiotics. Therefore, constructive removal of antibiotics from environmental matrices and other alternatives have been discussed. This review summarizes present scenario and removal of micro-pollutants, antibiotics from environment. Various strategies including physicochemical, bioremediation, use of bioreactor, and biocatalysts are recognized as potent antibiotic removal strategies. Microbial Fuel Cells (MFCs) and biochar have emerged as promising biodegradation processes due to low cost, energy efficient and environmental benignity. With higher removal rate (20-50%) combined/ hybrid processes seems to be more efficient for permanent and sustainable elimination of reluctant antibiotics., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

This work highlights the potential of corncob biochar (CCBC) and Brevibacillus parabrevis for the decolorization of brilliant green (BG) dye from synthetically prepared contaminated wastewater. The CCBC was characterized by proximate, Fourier-transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction, and Brunauer-Emmett-Teller analysis, respectively. Different parameters affecting the adsorption process were evaluated. The experimental results were analyzed by the Langmuir and Freundlich isotherm models. Kinetic results were examined by different models; pseudo-second-order model has shown the best fit to the experimental data. Anew positive values of ΔH o (172.58 kJ/mol) and ΔS o (569.97 J/K/mol) in the temperature range of 303-318  K revealed that the adsorption process was spontaneous and endothermic. The present investigation showed that the bacteria immobilized with CCBC showed better BG dye degradation. The kinetic parameters, μ max , Ks , and μ max , were found to be 0.5 per day, 39.4 mg/day, and 0.012 L/mg/day using Monod model, respectively. The adsorbent with bacteria showed good potential for the removal of cationic BG dye and can be considered for the remediation of industrial effluent.

Winter varieties of plants can flower only after exposure to prolonged cold. This phenomenon is known as vernalization and has been widely studied in the model plant Arabidopsis thaliana as well as in monocots. Through the repression of floral activator genes, vernalization prevents flowering in winter. In Arabidopsis, FLOWERING LOCUS C or FLC is the key repressor during vernalization, while in monocots vernalization is regulated through VRN1, VRN2 and VRN3 (or FLOWERING LOCUS T). Interestingly, VRN genes are not homologous to FLC but FLC homologs are found to have a significant role in vernalization response in cereals. The presence of FLC homologs in monocots opens new dimensions to understand, compare and retrace the evolution of vernalization pathways between monocots and dicots. In this review, we discuss the molecular mechanism of vernalization-induced flowering along with epigenetic regulations in Arabidopsis and temperate cereals. A better understanding of cold-induced flowering will be helpful in crop breeding strategies to modify the vernalization requirement of economically important temperate cereals., (© 2020 Scandinavian Plant Physiology Society.)

The biodegradation of naphthalene using low-density polyethylene (LDPE) immobilized Exiguobacterium sp. RKS3 (MG696729) in a packed bed bioreactor (PBBR) was studied. The performance of a continuous PBBR was evaluated at different inlet flow rates (IFRs) (20-100 mL/h) under 64 days of operation. The maximum naphthalene removal efficiency (RE) was found at low IFR, and it further decreased with increasing IFRs. In a continuous PBBR, the external mass transfer (EMT) aspect was analysed at various IFRs, and experimental data were interrelated between Colburn factor (J D ) and Reynolds number (N Re ) as [Formula: see text] . A new correlation [Formula: see text] was obtained to predict the EMT aspect of naphthalene biodegradation. Andrew-Haldane model was used to evaluate the bio-kinetic parameters of naphthalene degradation, and kinetic constant ν max , J s , and J i were found as 0.386 per day, 13.6 mg/L, and 20.54 mg/L, respectively., Competing Interests: Declaration of competing interest I declare that this is an original research work of the authors and all the authors have contributed in completion of this work, which is embedded in this paper. I also confirm that this work has not been published elsewhere nor it is currently under consideration for publication elsewhere. I have no any conflict of interest., (Copyright © 2020. Published by Elsevier Inc.)

Background: Accretion of organic and inorganic contaminants in soil interferes in the food chain, thereby posing a serious threat to the ecosystem and adversely affecting crop productivity and human life. Both endophytic and rhizospheric microbial communities are responsible for the biodegradation of toxic organic compounds and have the capability to enhance the uptake of heavy metals by plants via phytoremediation approaches. The diverse set of metabolic genes encoding for the production of biosurfactants and biofilms, specific enzymes for degrading plant polymers, modification of cell surface hydrophobicity and various detoxification pathways for the organic pollutants, plays a significant role in bacterial driven bioremediation. Various genetic engineering approaches have been demonstrated to modulate the activity of specific microbial species in order to enhance their detoxification potential. Certain rhizospheric bacterial communities are genetically modified to produce specific enzymes that play a role in degrading toxic pollutants. Few studies suggest that the overexpression of extracellular enzymes secreted by plant, fungi or rhizospheric microbes can improve the degradation of specific organic pollutants in the soil. Plants and microbes dwell synergistically, where microbes draw benefit by nutrient acquisition from root exudates whereas they assist in plant growth and survival by producing certain plant growth promoting metabolites, nitrogen fixation, phosphate solubilization, auxin production, siderophore production, and inhibition or suppression of plant pathogens. Thus, the plant-microbe interaction establishes the foundation of the soil nutrient cycle as well as decreases soil toxicity by the removal of harmful pollutants., Conclusion: The perspective of integrating genetic approach with bioremediation is crucial to evaluate connexions among microbial communities, plant communities and ecosystem processes with a focus on improving phytoremediation of contaminated sites., (© 2020 Bentham Science Publishers.)

The degrees of mineral carbonation in (a) construction and demolition waste (C&DW) and (b) a mixture of cement and fly ash were studied through a dynamic experimental method to determine the variation in the rate and extent of CO 2 sequestration achievable under simulated outdoor conditions. A number of experiments were performed in a self-designed rotating batch reactor by churning the two samples together with CO 2 , which was passed through the mixtures by using water vapor as the medium of transfer. At an injection flow rate of 1 L/min for CO 2 , the theoretical extent of carbonation was observed to be 39.1% for the mixture of cement and fly ash and 25% for C&DW. It was further observed that upon increasing the CO 2 flow rate to 10 L/min, the carbonation in the mixture of cement and fly ash increased by 37.2% after 15 h of rotation at 60 rounds per hour (rph) for a temperature of 40 °C. Weighing, scanning electron microscopy (SEM), and energy dispersive spectrometry (EDS) were performed for the samples before and after the batch reaction to study the quantitative, qualitative and morphological aspects of the process.

The performance of a moving bed biofilm reactor (MBBR) with bio-carriers made of polypropylene-polyurethane foam (PP-PUF) was evaluated for the collective removal of phenol and ammonia. Three independent variables, including pH (5.0-8.0), retention time (2.0-12.0 h), and airflow rate (0.8-3.5 L/min) were optimized using central composite design (CCD) of response surface methodology (RSM). The maximum removal of phenol and ammonia was obtained to be 92.6, and 91.8%, respectively, in addition to the removal of 72.3% in the chemical oxygen demand (COD) level at optimum conditions. First-order and second-order kinetic models were analyzed to evaluate the pollutants removal kinetics in a MBBR. Finally, a second-order model was found to be appropriate for predicting reaction kinetics. The values of second-order rate constants were obtained to be 2.35, 0.25, and 1.85 L 2 /gVSS gCOD h for phenol, COD, and ammonia removal, respectively., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The present studies aimed for the removal of Methylene blue (MB) dye using the rice husk biochar (RHB), cow dung biochar (CDB) and domestic sludge biochar (SB) synthesized through slow pyrolysis at 500 °C. The biochar was used for the adsorption of synthetic aqueous MB dye. The removal efficiencies of MB by CDB, RHB and SB in a batch experiment were 97.0-99.0; 71.0-99.0 and 73.0-98.9% at conditions, pH (2.0-11.0); Biochar dosage (0.5-6.0 g/100 mL) for 5 days. Adsorption isotherm of Langmuir constant (K L ) were obtained 0.101, 0.583 and 0.128 for RHB, CDB and SB respectively. Further, adsorption kinetics of pseudo first order for RHB, CDB and SB were 0.068, 0.018, and 0.066 while it was 0.031, 0.023 and 0.273 for pseudo second order kinetics. Thus, CDB was more effective adsorbent for the dye removal. The pHz values were 7.8, 6.3 and 6.0 for the CDB, RHB, and SB, respectively., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The biodegradation of Congo red dye was performed using polyurethane foam-polypropylene immobilized Bacillus sp. MH587030.1 in a moving bed biofilm reactor (MBBR). The central composite design (CCD) based response surface methodology (RSM) was used to optimize the process parameters; pH, Congo red concentration, and media filling ratio, and optimum conditions were observed to be 7.0, 50 mg/L, and 45%, respectively in batch MBBR. At optimum condition, MBBR was operated in continuous mode at different flow rates (25-100 mL/h) over a period of 564 h. The maximum removal efficiency (RE) and elimination capacity (EC) were obtained as 95.7% and 57.6 mg/L·day, respectively under steady-state. The kinetics of Congo red biodegradation at various flow rates were evaluated by a modified Stover-Kincannon model, and kinetic constants; K B and U max were found to be 0.253 g/L·day and 0.263 g/L·day, respectively., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The main aim of this work was to evaluate the performance of a biofilter packed with a mixture of compost and activated carbon, for gas-phase toluene removal under very high loading rates. Plaster of Paris was used as a binder to improve the mechanical strength and durability of the packing media. The biofilter was operated continuously for a period of ∼110 days and at four different flow rates (0.069, 0.084, 0.126 and 0.186 m -3  h -1 ), corresponding to toluene loading rates of 160-8759 g m -3  h -1 . The maximum elimination capacity (EC) achieved in this study was 6665 g m -3  h -1 , while the removal efficiency (RE) varied from ∼70 to >95% depending on the loading rate tested. The biofilter was able to remove >99% of toluene using Pseudomonas sp. RSST (MG 279053) as the dominant toluene degrading biocatalyst., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

In this work, modified plastic carriers; polypropylene (PP), low-density polyethylene- polypropylene (LDPE-PP), and polyurethane foam-polypropylene (PUF-PP) were developed and used in moving bed bioreactor (MBBR) for the wastewater treatment containing naphthalene. To optimized the process parameters using response surface methodology (RSM), two numerical variables; pH (5.0-9.0) and hydraulic retention time (HRT) (1.0-5.0 day) along with the type of carriers (PP, LDPE-PP, and PUF-PP) were selected as a categorical factor. At 7.0 pH and 5 days HRT, maximum removal efficiencies were observed to be 72.4, 84.4, and 90.2% for MBBR packed with PP, LDPE-PP, and PUF-PP carriers, respectively. Gas chromatography-mass spectrometry (GC-MS) analysis reveals catechol and 2-naphthol were observed as intermediate metabolites for naphthalene degradation. Modified Stover-Kincannon model was applied for biodegradation kinetic and constants were observed as U max : 0.476, 0.666, and 0.769 g/L.day and K B : 0.565, 0.755, and 0.874 g/L.day for PP, LDPE-PP, PUF-PP, respectively., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Bacterial species for metabolizing dye molecules were isolated from dye rich water bodies. The best microbial species for such an application was selected amongst the isolated bacterial populations by conducting methylene blue (MB) batch degradation studies with the bacterial strains using NaCl-yeast as a nutrient medium. The most suitable bacterial species was Alcaligenes faecalis (A. faecalis) according to 16S rDNA sequencing. Process parameters were optimized and under the optimum conditions (e.g., inoculum size of 3 mL, temperature of 30 °C, 150 ppm, and time of 5 days), 96.2% of MB was removed. Furthermore, the effectiveness for the separation of MB combining bio-film with biochar was measured by a bio-sorption method in a packed bed bioreactor (PBBR) in which microbes was immobilized. The maximum MB removal efficiencies, when tested with 50 ppm dye using batch reactors containing free A. faecalis cells and the same cells immobilized on the biochar surface, were found to be 81.5% and 89.1%, respectively. The PBBR operated in continuous recycle mode at high dye concentration of 500 ppm provided 87.0% removal of MB through second-order kinetics over 10 days. The % removal was found in the order of PBBR>Immobilized batch>Free cell. The standalone biochar batch adsorption of MB can be described well by the pseudo-second order kinetics (R 2 ≥ 0.978), indicating the major contribution of electron exchange-based valence forces in the sorption of MB onto the biochar surface. The Langmuir isotherm suggested a maximum monolayer adsorption capacity of 4.69 mg g -1 at 40 °C which was very close to experimentally calculated value (4.97 mg g -1 ). Moreover, the Casuarina seed biochar was reusable 5 times., (Copyright © 2019. Published by Elsevier Inc.)

The state-space model is identified using the identification tool of MATLAB, and the best fit of 99% of measured and simulated data was obtained. Further, state-space model was converted to a transfer function model and finally simplified to an unstable second order time-delay transfer function model. Internal model control based proportional integral derivative (IMC-PID) controller design method was proposed for unstable second order time delay with RHP zero (USOPDT) and successfully tested to the nonlinear bioreactor process model. The temperature of the bioreactor was successfully controlled by proposed controller in both cases setpoint and disturbance change. The performance of the controller was evaluated in terms of IAE, ISE, ITAE and the corresponding values of 20.99, 49.02 and 292.50 were obtained respectively. Proposed method shows better closed-loop performance in terms of IAE and settling time than the other reported methods for temperature control of bioreactor.

The rampant industrialization and unchecked growth of modern textile production facilities coupled with the lack of proper treatment facilities have proliferated the discharge of effluents enriched with toxic, baleful, and carcinogenic pollutants including dyes, heavy metals, volatile organic compounds, odorants, and other hazardous materials. Therefore, the development of cost-effective and efficient control measures against such pollution is imperative to safeguard ecosystems and natural resources. In this regard, recent advances in biotechnology and microbiology have propelled bioremediation as a prospective alternative to traditional treatment methods. This review was organized to address bioremediation as a practical option for the treatment of dyes by evaluating its performance and typical attributes. It further highlights the current hurdles and future prospects for the abatement of dyes via biotechnology-based remediation techniques., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The progress in modern agricultural practices could not have been realized without the large-scale contribution of assorted pesticides (e.g., organophosphates and nonorganophosphates). Precise tracking of these chemicals has become very important for safeguarding the environment and food resources owing to their very high toxicity. Hence, the development of sensitive and convenient sensors for the on-site detection of pesticides is imperative to overcome practical limitations encountered in conventional methodologies, which require skilled manpower at the expense of high cost and low portability. In this regard, the role of novel, advanced functional materials such as metal-organic frameworks (MOFs) has drawn great interest as an alternative for conventional sensory systems because of their numerous advantages over other nanomaterials. This review was organized to address the recent advances in applications of MOFs for sensing various pesticides because of their tailorable optical and electrical characteristics. It also provides in-depth comparison of the performance of MOFs with other nanomaterial sensing platforms. Further, we discuss the present challenges (e.g., potential bias due to instability under certain conditions, variations in the diffusion rate of the pesticide, chemical interferences, and the precise measurement of luminesce quenching) in developing robust and sensitive sensors by using tailored porosity, functionalities, and better framework stability.

During the past decade, biochar has attracted immense scientific interest for agricultural and environmental applications. A broad range of biochars with advantageous properties (e.g., high surface area, flexible architecture, and high porosity) has been developed for pollution abatement. Nevertheless, biochar suffers from certain drawbacks (e.g., limited sorption capacity for anions and poor mechanical properties) that limit their practical applicability. This review focuses on recent advancements in biochar technology, especially with respect to its technical aspects, the variables associated with removing phosphates from water, and the challenges for such abatement. The attention paid to the specific remediation of phosphate from water using biochar is limited (n=1114 - Scopus) compared to the application of biochar to other common water pollutants (n=3998 - Scopus). The subject warrants immediate rigorous research because of the undesirable effects of excess phosphate in water bodies. This review will thus facilitate the construction of a roadmap for further developments and the expansion of this challenging area of research., (Copyright © 2017 Elsevier B.V. All rights reserved.)

In the present study, bacterial species capable of degrading colour waste were isolated from the water bodies located near the carpet cluster in the Bhadohi district of U.P., India. Among the isolated species best one was selected on the basis of its capability to degrade Congo red in batch experiments using NaCl-Yeast as the nutrient media and further it was identified as Brevibacillus parabrevis using 16S rDNA sequencing. The process parameters were optimized for maximum degradation in batch experiments and found out to be: Inoculum size: 3 ml, Temperature: 30 °C, Time: 6 days leading to a removal of 95.71% of dye sample. The experiment showed that bacteria immobilized with coconut shell biochar in continuous mode showed much better degradation than batch study without immobilization. The kinetics parameters μ max , Ks, and μ max K s were found to be 0.461 per day, 39.44 mg/day, and 0.0117 L/mg/day using Monod model., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Benzene removal in free and immobilized cells on polyurethane foam (PUF) and polyvinyl alcohol (PVA)-alginate beads was studied using an indigenous soil bacterium Bacillus sp. M3 isolated from petroleum-contaminated soil. The important process parameters (pH, temperature and inoculums size) were optimized and found to be 7, 37°C and 6.0×10 8 CFU/mL, respectively. Benzene removals were observed to be 70, 84 and 90% within 9days in a free cell, immobilized PVA-alginate beads and PUF, respectively under optimum operating conditions. FT-IR and GC-MS analysis confirm the presence of phenol, 1,2-benzenediol, hydroquinone and benzoate as metabolites. The important kinetic parameter ratios (µ max /K s ; L/mg·day ) calculated using Monod model was found to be 0.00123 for free cell, 0.00159 for immobilized alginate beads and 0.002016 for immobilized PUF. Similarly inhibition constants (K i ; mg/L) calculated using Andrew-Haldane model was found to be 435.84 for free cell, 664.25 for immobilized alginate beads and 724.93 for immobilized PUF., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The main objective of this study was to evaluate the performance of wood charcoal as biofilter media under transient and high loading condition. Biofiltration of xylene was investigated for 150days in a laboratory scale unit packed with wood charcoal and inoculated with mixed microbial culture at the xylene loading rates ranged from 12 to 553gm -3 h -1 . The kinetic analysis of the xylene revealed absence of substrate inhibition and possibility of achieving higher elimination under optimum condition. The pH, temperature, pressure drop and CO 2 production rate were regularly monitored during the experiments. Throughout experimental period, the removal efficiency (RE) was found to be in the range of 65-98.7% and the maximum elimination capacity (EC) was 405.7gm -3 h -1 . Molecular characterization results show Bacillus sp. as dominating microbial group in the biofilm., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Removal of hydrogen sulfide (H 2 S) from biogas was investigated in a biochar column integrated with a bench-scale continuous-stirred tank reactor (CSTR) treating sulfate-laden wastewater. Synthetic wastewater containing sulfate concentrations of 200-2000mg SO 4 2- /L was used as substrate, and the CSTR was operated at an organic loading rate of 1.5g chemical oxygen demand (COD)/L·day and a hydraulic retention time (HRT) of 20days. The biochar was able to remove about 98.0 (±1.2)% of H 2 S for the ranges of concentrations from 105-1020ppmv, especially at high moisture content (80-85%). Very high H 2 S adsorption capacity (up to 273.2±1.9mg H 2 S/g) of biochar is expected to enhance the H 2 S oxidation into S 0 and sulfate. These findings bring a potentially novel application of sulfur-rich biochar as a source of sulfur, an essential but often deficient micro-nutrient in soils., (Copyright © 2017 Elsevier Ltd. All rights reserved.)