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The current study demonstrates the nutrient removal efficiency of algal-bacterial photobioreactors in the semi-batch mode for secondary treated domestic wastewater. The experiments were conducted to predict the optimum conditions for running a photobioreactor at a comparatively larger scale. The main focus was on optimizing illumination costs and n...
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... systems are a boon to human development and the only kind of phototrophic organisms which doesn't require land to grow. This aspect of algal system can to be utilized by designing the treatment reactors along vertical axis. A general schematic of cylindrical airlift and cylindrical air bubbling reactors have been pictorially shown in Fig. 3. Several past researches on cylindrical reactor configurations with their salient features are listed in Table 1. Most of the studies conducted were in laboratory scale with very few on larger scales. Solovchenko et al. (2014) have tried to treat 50 l alcohol distillery wastewater and successfully removed more than 97% nitrates and 77% ...
Citations
... These contaminants have been identified in water environments such as biota, sediments, and water in recent decades. Due to their low degradation potential, they have high bioaccumulation and lipophilic nature, and they may cause serious health risks to the aquatic environment (Ashok et al. 2019). As well as they are bioaccumulated in the muscular tissues of benthic and shellfish organisms (Álvarez-Ruiz et al. 2021). ...
... However, at high pH, the loss of pollutants across polymeric membranes has been investigated (Snyder et al. 2007). Apart from bioremediation, an increasingly popular technique involves the application of diverse algal, fungal, plant-based, and bacterial systems (Ashok et al. 2019). Microbial degradation is a more cost-effective and comfortable method of eliminating contaminants from industrial effluent, as it requires fewer operating conditions. ...
The eco-toxicological effects of industrial wastewater in different parts of the global ecosystem have been a prominent matter of concern over the last 20 years. To mitigate these effects, industrial wastewater should be pollutant-free, and as a result, different technologies, including conventional and non-conventional, have been introduced so far. Due to these technologies, conventional treatment technologies are uneconomical due to the high energy demand for removing industrial wastewater pollutants. So, with advancements in technology, non conventional technologies, including bio-electrochemical systems (BES), have been introduced and have proven environmentally sustainable. BES combines biology and electrochemistry to produce bioenergy and degrade pollutants from industrial wastewater. BES consumes energy in the chemical bonds of industrial wastes to efficiently degrade the contaminants. Apart from that, BES faces some major challenges, including high capital costs and scalability. BES scale-up challenges include electrode conductivity, sub-optimal contact, and high internal resistance between electrodes. The global demand for microbial fuel cells (MFC) was $8.60 million in 2017 and grew at a compound yearly growth rate of 11.2%, with a projected increase to $22.38 million by 2026. Thus, this review focuses on the pollutant release mechanisms of different industries that cause eco-toxicity threats to human health and water bodies. In addition, this study extensively discussed the pollution remediation by BES and factors affecting BES-based remediation.
... These fascinating characters are present in plants and it is such natural origin which has carbohydrate in its composition. The carbohydrate found in plants have all properties like biodegradable, biocompatible and non-toxic substances [10][11][12]. ...
The purpose of this study was to synthesize ecofriendly nano-composite in which agricultural waste (seeds of Tamarindus indica) was used to synthesize tamarind seed polysaccharides (TSP) and its composite with copper nanoparticles (Cu-NPs) for the purpose of green and clean environment as well as reduction of green-house gases. Confirmation of extracted TSP, synthesized nanocomposite was carried out using FTIR, SEM, PXRD and EDX techniques. In FTIR analysis TSP gives a strong broad peak at 3331 cm⁻¹ due to –OH group and in case of composite its intensity is reduced which might be due to the interactions between –OH and Cu⁺² ions. SEM analysis gives that TSP have irregular and rough surface while Cu-NPs exhibited spherical morphology and composite showed clustering of spherical shape to rough surface. EDX analysis quantitatively represented copper having atomic ratio 0.57 % which confirms the synthesis of composite. Furthermore, synthesized composite demonstrated excellent antibacterial activity against gram-positive (S.aureus) and gram-negative bacteria (E.coli) even greater than standard medicine (ciprofloxacin). From this study it was revealed that agriculture waste can be utilized to make environment green as well as synthesized composite from agricultural waste seed also displayed excellent antimicrobial activities which directs that they can be utilized in medical field. This study aims to assess the antimicrobial properties of the nanocomposite, aiming to contribute to the development of effective antimicrobial agents. Through these objectives, the research seeks to bridge the gap between green technology and antimicrobial efficacy, offering a promising avenue for both environmental conservation and healthcare advancements.
... These contaminants have been identified in water environments such as biota, sediments, and water in recent decades. Due to their low degradation potential, they have high bioaccumulation and lipophilic nature, and they may cause serious health risks to the aquatic environment (Ashok et al. 2019). As well as they are bioaccumulated in the muscular tissues of benthic and shellfish organisms (Álvarez-Ruiz et al. 2021). ...
... However, at high pH, the loss of pollutants across polymeric membranes has been investigated (Snyder et al. 2007). Apart from bioremediation, an increasingly popular technique involves the application of diverse algal, fungal, plant-based, and bacterial systems (Ashok et al. 2019). Microbial degradation is a more cost-effective and comfortable method of eliminating contaminants from industrial effluent, as it requires fewer operating conditions. ...
The eco-toxicological efects of industrial wastewater in diferent parts of the global ecosystem have been a prominent matter
of concern over the last 20 years. To mitigate these efects, industrial wastewater should be pollutant-free, and as a result,
diferent technologies, including conventional and non-conventional, have been introduced so far. Due to these technologies,
conventional treatment technologies are uneconomical due to the high energy demand for removing industrial wastewater
pollutants. So, with advancements in technology, non-conventional technologies, including bio-electrochemical systems
(BES), have been introduced and have proven environmentally sustainable. BES combines biology and electrochemistry
to produce bioenergy and degrade pollutants from industrial wastewater. BES consumes energy in the chemical bonds of
industrial wastes to efciently degrade the contaminants. Apart from that, BES faces some major challenges, including high
capital costs and scalability. BES scale-up challenges include electrode conductivity, sub-optimal contact, and high internal
resistance between electrodes. The global demand for microbial fuel cells (MFC) was $8.60 million in 2017 and grew at a
compound yearly growth rate of 11.2%, with a projected increase to $22.38 million by 2026. Thus, this review focuses on
the pollutant release mechanisms of diferent industries that cause eco-toxicity threats to human health and water bodies. In
addition, this study extensively discussed the pollution remediation by BES and factors afecting BES-based remediation
... This occurs when the CO 2 is injected into the photobioreactor system. It dissolves in an aqueous medium forming carbonic acid, which is then assimilated by the grown cyanobacteria through ionic equilibrium into bicarbonate ion [33,49]. The lowest remaining DIC content in the growth medium ranged from 2.1 ×10 − 05 to 4.68 ×10 − 05 kg observed in experiment with PFD 300 µmol/ (m 2 .s) ...
Innovative methods for effectively sequestering significant amounts of carbon dioxide (CO2) are required to address the ongoing problem of greenhouse gas emissions, which have increased in tandem with industrial development. Optimisation of the performance of the photobioreactor remains a challenge, despite the potential of using photobioreactors and cyanobacteria for bio sequestration. A potential solution lies in the development of a hybrid photobioreactor design. Thus, this study aims to develop a hybrid design of the photobioreactor equipped with tailor-made real-time monitoring system known as FCB2022 for cultivating Spirulina platensis. The performance is evaluated by monitoring real-time data such as pH, dissolved oxygen (DO), and temperature, alongside assessing the growth kinetic of cyanobacterium, CO2 sequestration, oxygen release rate and mass carbon balance. These assessments are conducted under varying photon flux densities (PFD) of 100µmol/ (m2.s), 200µmol/ (m2.s), and 300µmol/ (m2.s). The result demonstrates that FCB2022 exhibited high hydrodynamic performance with parameters like mixing time, circulation time, Reynold number, and empty bed residence time showing favourable values. The optimal ranges for temperature, pH, and dissolved oxygen are determined to be between 23.56 and 29.11 ⁰C, 9.03–9.58, and 6.57–6.89 mgO2/L, respectively. Under the conditions of 15% CO2 and PFD of 300µmol/ (m2.s), the specific growth rates reach 0.36±0.004 /day and maximum biomass concentration attains 1.52±0.03 kg/m3. Notably, the PFD of 300µmol/ (m2.s) yields the highest conversion of carbon into biomass, ranging from 1.09×10 02 kg to 1.26×10 02kg, representing the yield of 31–83% in each CO2 injection treatment.
... Microalgae use photosynthesis to convert light into chemical energy, fueling their metabolic activities. Therefore, an adequate and consistent supply of light is essential to support microalgae growth and optimize their remediation capabilities [133,134]. Microalgae cultivation typically involves constructing open ponds or closed bioreactors, which must be exposed to sunlight for extended periods. The land area required can be significant, especially when aiming to achieve high biomass productivity and efficient pollutant removal. ...
The textile industry is a growing sector worldwide and has immense opportunity in terms of providing employment and boosting a nation’s economy. However, there exist severe environmental risks associated with textile effluents that impact the surrounding ecosystem. This review offers an approach for sustainable water management using phycoremediation to treat dye-laden wastewater and recover bio-based pigments from the residual biomass. Microalgae such as Chlorella, Scenedesmus, Phormidium, and macroalgae like Sargassum, Enteromorpha, and Codium has been extensively used in several phycoremediation-based studies, and their residual biomass could be a potent source for extraction of bio-based pigments. This review also recommends studies involving the algal-bacterial consortia approach for treating dye-laden wastewater as an alternative to conventional, biobased methods. The outcome of this study will provide policymakers and researchers with new insight to manage water and wastewater resources sustainably. Furthermore, this review also enhances our understanding of nature-based decontamination approaches for treating dye-laden wastewater through algal-based technologies.
... The correlations between the biodegradation efficiency of SMX and CAP and the surface area of BC and MBC were analyzed (Fig. 2a, b). The biodegradation efficiencies were positively correlated with the surface of BC (r = 0.631, p < 0.01) (Fig. 2a) and MBC (r = 0.749) (Fig. 2b), indicating that the surface area of BC and MBC could be used as the carrier to increase the bacterial growth and improve the biodegradation efficiencies of SMX and CAP (Ashok et al. 2019). In particular, the content of BDOM was markedly linearly correlated with the biodegradation efficiency of SMX and CAP (r = 0.857, Fig. 2c), resulting in BDOM released from BC being a key factor influencing the biodegradation efficiency of SMX and CAP under the alternating conditions of xenon lamp irradiation and avoiding light. ...
The influence of biochar-released dissolved organic matter (BDOM) on the transcription of gene (DEG) in Pseudomonas stutzeri and Shewanella putrefacien during sulfamethoxazole (SMX) and chloramphenicol (CAP) biodegradation under visible light was investigated in this study. The results indicated that BDOM components would be nutrients for bacterial amplification and growth under the culture conditions of xenon lamp irradiation and avoiding light, especially BDOM from low temperatures. Additionally, visible light irradiation would improve the saturated fatty acid by stimulating the cell membrane of the microorganism, thus promoting the biodegradation of antibiotics through altering P. stutzeri and S. putrefaciens reoxidative and catabolism processes and significantly inhabiting the copy number of their genes. Moreover, the upregulated genes and enzymes related to SMX and CAP-metabolic and catabolic processes were enriched, which were involved in the pathways of biodegradation, further improving biodegradation efficiency. In particular, interaction network analysis between the top 100 dominant functional genes from P. stutzeri and S. putrefaciens and the molecular types of BDOM, e.g., CHO, CHON, and CHOS ( p < 0.05), indicated that the genes of molecular function showed a high positive or negative correlation with the CHO type of BDOM. The results revealed that the CHO type of BDOM affected the functional genes of molecular function, cellular component, and biological process from P. stutzeri and S. putrefaciens , influencing the biodegradation of SMX and CAP. This study provided an basis for BDOM playing a role in antibiotic removal from the aqueous solution using biochar combined with photobiodegradation.
Graphical Abstract
... Bioremediation of xenobiotics compounds is one of the emerging practices. Efforts are being made to remove various types of pollutants and nutrient recovery using different bacteriological, fungal, algal, and plant-based bioremediation systems [9,88,91]. Biological degradation and transformation of recalcitrant or persistent compounds are very slow or nearly impossible. Tremendous efforts are being made to adapt various types of microorganisms to such substrates. ...
Xenobiotics are considered toxic and a major threat to human beings by finding their way to various segments of the environment. Conventional wastewater treatment is uneconomical in removing these contaminants due to high energy demands. The technological advent has shifted towards applying the bioelectrochemical system (BES) for the integrated treatment of wastewater. BES, being an environment-friendly process, has promising potential in the bioremediation of xenobiotics. The BES technology has dual advantages of treating the contaminants present in wastewater with the support of electrochemically active microbes and bioenergy production. BES utilizes the energy stored in the chemical bonds of wastes for the treatment of these wastes. The MFC has gained prominence as it can simultaneously treat wastewater and generates electricity. The BES's major limitations are its scalability and high capital cost. The challenges for the scale-up of the BES include a high internal resistance, limited electrode conductivity, and sub-optimal contacts between the electrodes. The global market for microbial fuel cells (a type of BES) has accounted for $8.60 million in 2017 and grew at a compound annual growth rate of 11.2%, which is anticipated to increase to $22.38 million by 2026.
... The effect of flashing light and continuous light from red light-emitting diodes in a biofilm reactor using a microalgae consortium was evaluated for CO 2 fixation, observing that flashing light increases CO 2 uptake in bioreactors type (Martín-Girela et al. 2017). The use of biofilm reactors has also shown favorable results in removing phosphorus, nitrogen, and ammonia, showing that light intensity and retention time are the main factors that affect the ability of microalgae to remove pollutants (Ashok et al. 2019). ...
Due to growing pollution concerns over the years, researchers are evaluating various optimization strategies to develop efficient bioremediation alternatives. Bioremediation encompasses numerous process types and each type and pollutant target require a different optimization approach. This chapter intends to provide an overview of knowledge gained from the bioremediation optimization studies performed to treat the most common pollutants. Available literature was classified according to bioremediation types affected by similar processing factors, viz., phytoremediation, bioaugmentation and biostimulation (in-situ bioremediation) and bioreactors, biosorption and enzymatic treatment (ex-situ bioremediation). We discussed and compared the optimization approach followed in each bioremediation type, critical factors affecting the processes, quality targets and process design. This chapter will provide a scientific and technical basis that can assist in the selection of design, process improvement, optimization and implementation of the bioremediation technology.
... The effect of flashing light and continuous light from red light-emitting diodes in a biofilm reactor using a microalgae consortium was evaluated for CO 2 fixation, observing that flashing light increases CO 2 uptake in bioreactors type (Martín-Girela et al. 2017). The use of biofilm reactors has also shown favorable results in removing phosphorus, nitrogen, and ammonia, showing that light intensity and retention time are the main factors that affect the ability of microalgae to remove pollutants (Ashok et al. 2019). ...
Pollution is an ever-increasing global problem linked with industrialization, urbanization, and population growth. Bioremediation is a sustainable method to curb this threat with minimum adverse effect on the environment. The chapter reviews the recent bioremediation approaches to eliminate the contaminants in water, soil, and air. Genetics and phenotypic properties of extremophiles provide a wealth of knowledge to grey-biotechnology to develop novel biological strategies for bioremediation. From this point of view, novel advances in biotechnology focusses on genetic engineering of organisms and proteins to improve their capabilities in degrading pollutants and restoring natural environment. Genetically modified organisms have been successfully introduced into contaminated sites worldwide. However, special attention is necessary to determine the direct and indirect risks associated with the release of genetically engineered organisms into sensitive environments. This chapter further describes the future strategies to improve the efficiency of bioremediation.
... The effect of flashing light and continuous light from red light-emitting diodes in a biofilm reactor using a microalgae consortium was evaluated for CO 2 fixation, observing that flashing light increases CO 2 uptake in bioreactors type (Martín-Girela et al. 2017). The use of biofilm reactors has also shown favorable results in removing phosphorus, nitrogen, and ammonia, showing that light intensity and retention time are the main factors that affect the ability of microalgae to remove pollutants (Ashok et al. 2019). ...
Pollutants and toxicants in the environment are a major source of concern through around the world; pollutants include heavy metals, pesticides, organic compounds, dye, oil or industrial waste. There have been a slew of reports over last decades on cost effective waste cleanup technologies. Pollutant removal from the ecosystem is problematic due to their longevity, inability to biodegrade and pervasiveness. Environmental pollutant removal through the microbial perspective is apprises eco-friendly as well as a better alternative to conventional approaches. Microbes remove toxins by enzymatic or metabolic reactions such as eradication, immobilization, oxidation or detoxification. Various biotic or abiotic factors may influence the degradation mechanism, but various in situ or ex situ bioremediation techniques are used to degrade toxins all over the planet. Maximum bioremediation processes occurs in aerobic conditions, but for recalcitrant molecules anaerobic conditions are suitable. Microbial aided remediation demonstrates novel strategies for reducing pollutant and toxicant level in environment.
