The Use of Algae and Fungi for Removal of Pharmaceuticals by Bioremediation and Biosorption Processes: A Review

Impact of veterinary pharmaceuticals on environment and their mitigation through microbial bioremediation

Veterinary medications are constantly being used for the diagnosis, treatment, and prevention of diseases in livestock. However, untreated veterinary drug active compounds are interminably discharged into numerous water bodies and terrestrial ecosystems, during production procedures, improper disposal of empty containers, unused medication or animal feed, and treatment procedures. This exhaustive review describes the different pathways through which veterinary medications enter the environment, discussing the role of agricultural practices and improper disposal methods. The detrimental effects of veterinary drug compounds on aquatic and terrestrial ecosystems are elaborated with examples of specific veterinary drugs and their known impacts. This review also aims to detail the mechanisms by which microbes degrade veterinary drug compounds as well as highlighting successful case studies and recent advancements in microbe-based bioremediation. It also elaborates on microbial electrochemical technologies as an eco-friendly solution for removing pharmaceutical pollutants from wastewater. Lastly, we have summarized potential innovations and challenges in implementing bioremediation on a large scale under the section prospects and advancements in this field.

Searching for Chemical Agents Suppressing Substrate Microbiota in White-Rot Fungi Large-Scale Cultivation

Edible fungi are a valuable resource in the search for sustainable solutions to environmental pollution. Their ability to degrade organic pollutants, extract heavy metals, and restore ecological balance has a huge potential for bioremediation. They are also sustainable food resources. Edible fungi (basidiomycetes or fungi from other divisions) represent an underutilized resource in the field of bioremediation. By maximizing their unique capabilities, it is possible to develop innovative approaches for addressing environmental contamination. The aim of the present study was to find selective chemical agents suppressing the growth of microfungi and bacteria, but not suppressing white-rot fungi, in order to perform large-scale cultivation of white-rot fungi in natural unsterile substrates and use it for different purposes. One application could be the preparation of a matrix composed of wooden sleeper (contaminated with PAHs) and soil for further hazardous waste bioremediation using white-rot fungi. In vitro microbiological methods were applied, such as, firstly, compatibility tests between bacteria and white-rot fungi or microfungi, allowing us to evaluate the interaction between different organisms, and secondly, the addition of chemicals on the surface of a Petri dish with a test strain of microorganisms of white-rot fungi, allowing us to determine the impact of chemicals on the growth of organisms. This study shows that white-rot fungi are not compatible to grow with several rhizobacteria or bacteria isolated from soil and bioremediated waste. Therefore, the impact of several inorganic materials, such as lime (hydrated form), charcoal, dolomite powder, ash, gypsum, phosphogypsum, hydrogen peroxide, potassium permanganate, and sodium hydroxide, was evaluated on the growth of microfungi (sixteen strains), white-rot fungi (three strains), and bacteria (nine strains) in vitro. Charcoal, dolomite powder, gypsum, and phosphogypsum did not suppress the growth either of microfungi or of bacteria in the tested substrate, and even acted as promoters of their growth. The effects of the other agents tested were strain dependent. Potassium permanganate could be used for bacteria and Candida spp. growth suppression, but not for other microfungi. Lime showed promising results by suppressing the growth of microfungi and bacteria, but it also suppressed the growth of white-rot fungi. Hydrogen peroxide showed strong suppression of microfungi, and even had a bactericidal effect on some bacteria, but did not have an impact on white-rot fungi. The study highlights the practical utility of using hydrogen peroxide up to 3% as an effective biota-suppressing chemical agent prior to inoculating white-rot fungi in the large-scale bioremediation of polluted substrates, or in the large-scale cultivation for mushroom production as a foodstuff.

The biotechnological potential of the Chloroflexota phylum

In the next decades, the increasing material and energetic demand to support population growth and higher standards of living will amplify the current pressures on ecosystems and will call for greater investments in infrastructures and modern technologies. A valid approach to overcome such future challenges is the employment of sustainable bio-based technologies that explore the metabolic richness of microorganisms. Collectively, the metabolic capabilities of Chloroflexota, spanning aerobic and anaerobic conditions, thermophilic adaptability, anoxygenic photosynthesis, and utilization of toxic compounds as electron acceptors, underscore the phylum's resilience and ecological significance. These diverse metabolic strategies, driven by the interplay between temperature, oxygen availability, and energy metabolism, exemplify the complex adaptations that enabled Chloroflexota to colonize a wide range of ecological niches. In demonstrating the metabolic richness of the Chloroflexota phylum, specific members exemplify the diverse capabilities of these microorganisms: Chloroflexus aurantiacus showcases adaptability through its thermophilic and phototrophic growth, whereas members of the Anaerolineae class are known for their role in the degradation of complex organic compounds, contributing significantly to the carbon cycle in anaerobic environments, highlighting the phylum's potential for biotechnological exploitation in varying environmental conditions. In this context, the metabolic diversity of Chloroflexota must be considered a promising asset for a large range of applications. Currently, this bacterial phylum is organized into eight classes possessing different metabolic strategies to survive and thrive in a wide variety of extreme environments. This review correlates the ecological role of Chloroflexota in such environments with the potential application of their metabolisms in biotechnological approaches.

Evaluation of surfactant-aided polycyclic aromatic hydrocarbon biodegradation by molecular docking and molecular dynamic simulation in the marine environment

Marine oil spills directly cause polycyclic aromatic hydrocarbons (PAHs) pollution and affect marine organisms due to their toxic property. Chemical and bio-based dispersants composed of surfactants and solvents are considered effective oil spill-treating agents. Dispersants enhance oil biodegradation in the marine environment by rapidly increasing their solubility in the water column. However, the effect of dispersants, especially surfactants, on PAHs degradation by enzymes produced by microorganisms has not been studied at the molecular level. The role of the cytochrome P450 (CYP) enzyme in converting contaminants into reactive metabolites during the biodegradation process has been evidenced, but the activity in the presence of surfactants is still ambiguous. Thus, this study focused on the evaluation of the impact of chemical and bio-surfactants (i.e., Tween 80 (TWE) and Surfactin (SUC)) on the biodegradation of naphthalene (NAP), chrysene (CHR), and pyrene (PYR), the representative components of PAHs, with CYP enzyme from microalgae Parachlorella kessleri using molecular docking and molecular dynamics (MD) simulation. The molecular docking analysis revealed that PAHs bound to residues at the CYP active site through hydrophobic interactions for biodegradation. The MD simulation showed that the surfactant addition changed the enzyme conformation in the CYP-PAH complexes to provide more interactions between the enzyme and PAHs. This led to an increase in the enzyme's capability to degrade PAHs. Binding free energy (ΔG‌‌Bind) calculations confirmed that surfactant treatment could enhance PAHs degradation by the enzyme. The SUC gave a better result on NAP and PYR biodegradation based on ΔG‌‌Bind, while TWE facilitated the biodegradation of CHR. The research outputs could greatly facilitate evaluating the behaviors of oil spill-treating agents and oil spill response operations in the marine environment.

Removal of contaminants of emerging concern from pig manure in different operation stages of a thin-layer cascade photobioreactor. Relationship with concentrations in microalgae and manure

The performance of a pilot-scale thin-layer cascade photobioreactor, operated in semicontinuous mode, for the removal of veterinary drug residues and other contaminants of emerging concern (CECs) from pig manure has been assessed in six operation stages. Chlorella sp. (70-90%), Scenedesmus sp. (10-25%) and Diatomea (<5%) comprise the microalgae species present during the stages. The global performance to remove the total CEC content in the photobioreactor effluent varied from 62 to 86% on each stage, while an CEC mean amount close to 8% was accumulated in the photobioreactor biomass. A relation with weather conditions was not observed. Elimination ratio was not related to the concentration in the influent which reached up to 8000 ng L-1 for some CECs. As expected, the concentrations of veterinary drugs were higher than those of non-veterinary CECs. The concentrations accumulated in the grown biomass were relative low, lower than 10 ng per fresh g excepting for a few cases. However, statistical data suggested that the linkage of CECs to microalgae biomass boosted their removal from the influent. Furthermore, it was observed that the manure liquid phase contained higher amounts of CECs than the solid phase.

A Sustainable Banana Peel Activated Carbon for Removing Pharmaceutical Pollutants from Different Waters: Production, Characterization, and Application

Due to the growing concerns about pharmaceutical contamination and its devastating impact on the economy and the health of humans and the environment, developing efficient approaches for removing such contaminants has become essential. Adsorption is a cost-effective technique for removing pollutants. Thus, in this work, banana peels as agro-industrial waste were utilized for synthesizing activated carbon for removing pharmaceuticals, namely amoxicillin and carbamazepine from different water matrices. The chemically activated carbon by phosphoric acid (H3PO4) was carbonized at temperatures 350 °C, 450 °C and 550 °C. The material was characterized by several techniques such as scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS), Fourier transform infrared spectroscopy (FTIR), Boehm titration, point of zero charge (pHPZC), BET surface area (SBET), the proximate and ultimate analyses, X-ray powder diffraction (XRD), and thermos-gravimetric analysis (TGA). The SEM of banana peel activated carbon (BPAC) depicted a semi-regular and heterogeneous morphology, characterized by an abundance of pores with diverse forms and sizes. Boehm titration revealed an increase in the amounts of acidic groups by 0.711 mmol/g due to activation by H3PO4. FTIR recorded different peaks suggesting significant modifications in the spectroscopic characteristics of the BPAC surface due to the successful activation and adsorption of the pollutant molecules. The pHpzc of BPAC was calculated to be 5.005. The SBET surface area dramatically increased to 911.59 m2/g after the activation. The optimum conditions were 25 °C, a materials dosage of 1.2 g/L, a saturation time of 120 min, a pollutants mixture of 25 mg/L, and a pH of 5. Langmuir exhibits a slightly better fit than Freundlich with a low value of the residual sum of squares (SSE) and the data were better fitted to the pseudo-second-order kinetic. Furthermore, the efficacy of BPAC in eliminating pharmaceuticals from Milli Q water, lake water, and wastewater was successfully investigated over the seven cycles. The results of the present work highlighted a potential usage of agro-industrial waste in eliminating organic micropollutants while exhibiting sustainable management of this waste.

Pharmaceutically active micropollutants: origin, hazards and removal

Pharmaceuticals, recognized for their life-saving potential, have emerged as a concerning class of micropollutants in the environment. Even at minute concentrations, chronic exposure poses a significant threat to ecosystems. Various pharmaceutically active micropollutants (PhAMP), including antibiotics, analgesics, and hormones, have been detected in underground waters, surface waters, seawater, sewage treatment plants, soils, and activated sludges due to the absence of standardized regulations on pharmaceutical discharge. Prolonged exposureof hospital waste and sewage treatment facilities is linked to the presence of antibiotic-resistant bacteria. Conventional water treatment methods prove ineffective, prompting the use of alternative techniques like photolysis, reverse osmosis, UV-degradation, bio-degradation, and nano-filtration. However, commercial implementation faces challenges such as incomplete removal, toxic sludge generation, high costs, and the need for skilled personnel. Research gaps include the need to comprehensively identify and understand various types of pharmaceutically active micropollutants, investigate their long-term ecological impact, develop more sensitive monitoring techniques, and explore integrated treatment approaches. Additionally, there is a gap in understanding the socio-economic implications of pharmaceutical pollution and the efficacy of public awareness campaigns. Future research should delve into alternative strategies like phagotherapy, vaccines, and natural substance substitutes to address the escalating threat of pharmaceutical pollution.

An investigation on protein and amino acid contents in scales and muscles of pomfret Parastromateus niger (Bloch, 1795) and Pampus argenteus (Eupharasen, 1788)

Abstract The present investigation was aimed to examine the percentage quantity of protein and amino acids in scales and muscles of Pampus argenteus and Parastromateus niger gathered from the local fish market of district Quetta of Balochistan. About 80 specimens of these two species, i.e., Pampus argenteus (N=40) and Parastromateus niger (N = 40), were collected from April 2017 to May 2018. In general, crude protein content was high in scales, that is, 71.03% in Parastromateus niger and 52.11% in Pampus argenteus, as well as in muscles of two Pomfret species of fishes i.e., 63.44% in Pampus argenteus and 60.99% in Parastromateus niger on a dry-weight basis, respectively. Likewise, the muscles and scales of Parastromateus niger reveal well compositions of amino acids that include proline was found to be high, and methionine was less than other amino acids, whereas threonine was found high in the scales of Pampus argenteus, but methionine was observed in lesser amount. However, the amino acids found in Pampus argenteus muscles also showed different compositions, such as lysine was found to be high, but histidine was less, respectively. In comparison, amino acids like tryptophan and cysteine were not detected in both scales and muscles of thesePomfret species of fishes. Thus, this study was based on analyzing the utilization of both Pomfret species of scales and meat whether they could have values as good supplements of both protein and certain kinds of essential amino acids in animal diets.

Environmental fate of aquatic pollutants and their mitigation by phycoremediation for the clean and sustainable environment: A review

Emerging pollutants such as natural and manufactured chemicals, insecticides, pesticides, surfactants, and other biological agents such as personal care products, cosmetics, pharmaceuticals, and many industrial discharges hamper the aquatic environment. Nanomaterials and microplastics, among the categories of pollutants, can directly interfere with the marine ecosystem and translate into deleterious effects for humans and animals. They are either uncontrolled or poorly governed. Due to their known or suspected effects on human and environmental health, some chemicals are currently causing concern. The aquatic ecology is at risk from these toxins, which have spread worldwide. This review assesses the prevalence of emerging and hazardous pollutants that have effects on aquatic ecosystems and contaminated water bodies and their toxicity to non-target organisms. Microalgae are found to be a suitable source to remediate the above-mentioned risks. Microalgae based mitigation techniques are currently emerging approaches for all such contaminants, including the other categories that are discussed above. These studies describe the mechanism of phycoremediation, provide outrage factors that may significantly affect the efficiency of contaminants removal, and discuss the future directions and challenges of microalgal mediated remediations.

Acetaminophen-traces bioremediation with novel phenotypically and genotypically characterized 2 Streptomyces strains using chemo-informatics, in vivo, and in vitro experiments for cytotoxicity and biological activity

We isolated two novel bacterial strains, active against the environmental pollutant acetaminophen/Paracetamol®. Streptomyces chrestomyceticus (symbol RS2) and Flavofuscus (symbol M33) collected from El-Natrun Valley, Egypt-water, sediment, and sand samples, taxonomically characterized using a transmission electron microscope (TEM). Genotypic identification, based on 16S rRNA gene sequence analysis followed by BLAST alignment, were deposited on the NCBI as 2 novel strains https://www.ncbi.nlm.nih.gov/nuccore/OM665324  and https://www.ncbi.nlm.nih.gov/nuccore/OM665325 . The phylogenetic tree was constructed. Acetaminophen secondary or intermediate product's chemical structure was identified by GC/LC MS. Some selected acetaminophen secondary-product extracts and derived compounds were examined against a panel of test micro-organisms and fortunately showed a good anti-microbial effect. In silico chemo-informatics Swiss ADMET evaluation was used in the selected bio-degradation extracts for absorption (gastric), distribution (to CNS), metabolism (hepatic), excretion (renal), and finally not toxic, being non-mutagenic/teratogenic or genotoxic, virtually. Moreover, in vitro cytotoxic activity of these selected bio-degradation secondary products was examined against HepG2 and MCF7 cancer cell lines, where M33 and RS2 extract effects on acetaminophen/paracetamol bio-degradation products were safe, with higher IC50 on HepG2 and MCF7 than the acetaminophen/paracetamol IC50 of 108.5 μg/ml. Moreover, an in vivo oral acute single-dose toxicity experiment was conducted, to confirm these in vitro and in silico lower toxicity (better safety) than acetaminophen/paracetamol.

Combining computational tools and experimental studies towards endocrine disruptors mitigation: A review of biocatalytic and adsorptive processes

The endocrine disruptors (EDCs) are an important group of emerging contaminants, and their mitigation has been a huge challenge due to their chemistry complexity and variety of these compounds. The traditional treatments are inefficient to completely remove EDCs, and adsorptive processes are the major alternative investigated on their removal. Also, the use of EDCs degrading enzymes has been encouraged due to ecofriendly approach of biocatalytic processes. This paper highlights the occurrence, classification, and toxicity of EDCs with special focus in the use of enzyme-based and adsorptive technologies in the elimination of EDCs from ambiental matrices. Numerous prior reviews have focused on the discussions toward these technologies. However, the literature lacks theoretical discussions about important aspects of these methods such as the mechanisms of EDCs adsorption on the adsorbent surface or the interactions between degrading enzymes - EDCs. In this sense, theoretical calculations combined to experimental studies may help in the development of more efficient technologies to EDCs mitigation. In this review, we point out how computational tools such as molecular docking and molecular dynamics have to contribute to the design of new adsorbents and efficient catalytic processes towards endocrine disruptors mitigation.

Pollutants in aquatic system: a frontier perspective of emerging threat and strategies to solve the crisis for safe drinking water

Water is an indispensable natural resource and is the most vital substance for the existence of life on earth. However, due to anthropogenic activities, it is being polluted at an alarming rate which has led to serious concern about water shortage across the world. Moreover, toxic contaminants released into water bodies from various industrial and domestic activities negatively affect aquatic and terrestrial organisms and cause serious diseases such as cancer, renal problems, gastroenteritis, diarrhea, and nausea in humans. Therefore, water treatments that can eliminate toxins are very crucial. Unfortunately, pollution treatment remains a difficulty when four broad considerations are taken into account: effectiveness, reusability, environmental friendliness, and affordability. In this situation, protecting water from contamination or creating affordable remedial techniques has become a serious issue. Although traditional wastewater treatment technologies have existed since antiquity, they are both expensive and inefficient. Nowadays, advanced sustainable technical approaches are being created to replace traditional wastewater treatment processes. The present study reviews the sources, toxicity, and possible remediation techniques of the water contaminants.

Removal of organic and inorganic contaminants from the air, soil, and water by algae

Rapid increases in human populations and development has led to a significant exploitation of natural resources around the world. On the other hand, humans have come to terms with the consequences of their past mistakes and started to address current and future resource utilization challenges. Today's primary challenge is figuring out and implementing eco-friendly, inexpensive, and innovative solutions for conservation issues such as environmental pollution, carbon neutrality, and manufacturing effluent/wastewater treatment, along with xenobiotic contamination of the natural ecosystem. One of the most promising approaches to reduce the environmental contamination load is the utilization of algae for bioremediation. Owing to their significant biosorption capacity to deactivate hazardous chemicals, macro-/microalgae are among the primary microorganisms that can be utilized for phytoremediation as a safe method for curtailing environmental pollution. In recent years, the use of algae to overcome environmental problems has advanced technologically, such as through synthetic biology and high-throughput phenomics, which is increasing the likelihood of attaining sustainability. As the research progresses, there is a promise for a greener future and the preservation of healthy ecosystems by using algae. They might act as a valuable tool in creating new products.

Dechlorination of wastewater from shell-based glucosamine processing by mangrove wetland-derived fungi

Wastewater from processing crustacean shell features ultrahigh chloride content. Bioremediation of the wastewater is challenging due to the high chloride ion content, making it inhospitable for most microorganisms to survive and growth. In this study, mangrove wetland-derived fungi were first tested for their salt tolerance, and the highly tolerant isolates were cultured in shrimp processing wastewater and the chloride concentration was monitored. Notably, the filamentous fungal species Aspergillus piperis could remove over 70% of the chloride in the wastewater within 3 days, with the fastest biomass increase (2.01 times heavier) and chloride removal occurring between day one and two. The chloride ions were sequestered into the fungal cells. The genome of this fungal species contained Cl- conversion enzymes, which may have contributed to the ion removal. The fungal strain was found to be of low virulence in larval models and could serve as a starting point for further considerations in bioremediation of shell processing wastewater, promoting the development of green technology in the shell processing industry.

Biochar-layered double hydroxide composites for the adsorption of tetracycline from water: synthesis, process modeling, and mechanism

Antibiotic-contaminated water is a crucial issue worldwide. Thus, in this study, the MgFeCa-layered double hydroxides were supported in date palm-derived biochar (B) using co-precipitation, hydrothermal, and co-pyrolysis methods. It closes gaps in composite design for pharmaceutical pollutant removal, advances eco-friendly adsorbents, and advances targeted water cleanup by investigating synthesis methodologies and gaining new insights into adsorption. The prepared B-MgFeCa composites were investigated for tetracycline (TC) adsorption from an aqueous solution. The B-MgFeCa composites synthesized through co-precipitation and hydrothermal methods exhibited better crystallinity, functional groups, and well-developed LDH structure within the biochar matrix. However, the co-pyrolysis method resulted in the LDH structure breakage, leading to the low crystalline composite material. The maximum adsorption of TC onto all B-MgFeCa was obtained at an acidic pH range (4-5). The B-MgFeCa composites produced via hydrothermal and co-pyrolysis methods showed higher and faster TC adsorption than the co-precipitation method. The kinetic results can be better described by Langmuir kinetic and mixed order models at low and high TC concentrations, indicating that the rate-limiting step is mainly associated with active binding sites adsorption. The Sip and Freundlich models showed better fitting with the equilibrium data. The TC removal by B-MgFeCa composites prepared via hydrothermal, the highest estimated uptake which is around 639.76 mg.g-1 according to the Sips model at ambient conditions, and co-pyrolysis was mainly dominated by physical and chemical interactions. The composite obtained via the co-precipitation method adsorbed TC through chemical bonding between surface functional groups with anionic species of TC molecule. The B-MgFeCa composite showed excellent reusability performance for up to five cycles with only a 30% decrease in TC removal efficiency. The results demonstrated that B-MgFeCa composites could be used as promising adsorbent materials for effective wastewater treatment.

The potential of fungi in the bioremediation of pharmaceutically active compounds: a comprehensive review

The ability of fungal species to produce a wide range of enzymes and metabolites, which act synergistically, makes them valuable tools in bioremediation, especially in the removal of pharmaceutically active compounds (PhACs) from contaminated environments. PhACs are compounds that have been specifically designed to treat or alter animal physiological conditions and they include antibiotics, analgesics, hormones, and steroids. Their detrimental effects on all life forms have become a source of public outcry due their persistent nature and their uncontrolled discharge into various wastewater effluents, hospital effluents, and surface waters. Studies have however shown that fungi have the necessary metabolic machinery to degrade PhACs in complex environments, such as soil and water, in addition they can be utilized in bioreactor systems to remove PhACs. In this regard, this review highlights fungal species with immense potential in the biodegradation of PhACs, their enzymatic arsenal as well as the probable mechanism of biodegradation. The challenges encumbering the real-time application of this promising bioremediative approach are also highlighted, as well as the areas of improvement and future perspective. In all, this paper points researchers to the fact that fungal bioremediation is a promising strategy for addressing the growing issue of pharmaceutical contamination in the environment and can help to mitigate the negative impacts on ecosystems and human health.

Insights into Recent Advances of Biomaterials Based on Microbial Biomass and Natural Polymers for Sustainable Removal of Pharmaceuticals Residues

Pharmaceuticals are acknowledged as emerging contaminants in water resources. The concentration of pharmaceutical compounds in the environment has increased due to the rapid development of the pharmaceutical industry, the increasing use of human and veterinary drugs, and the ineffectiveness of conventional technologies to remove pharmaceutical compounds from water. The application of biomaterials derived from renewable resources in emerging pollutant removal techniques constitutes a new research direction in the field. In this context, the article reviews the literature on pharmaceutical removal from water sources using microbial biomass and natural polymers in biosorption or biodegradation processes. Microorganisms, in their active or inactive form, natural polymers and biocomposites based on inorganic materials, as well as microbial biomass immobilized or encapsulated in polymer matrix, were analyzed in this work. The review examines the benefits, limitations, and drawbacks of employing these biomaterials, as well as the prospects for future research and industrial implementation. From these points of view, current trends in the field are clearly reviewed. Finally, this study demonstrated how biocomposites made of natural polymers and microbial biomass suggest a viable adsorbent biomaterial for reducing environmental pollution that is also efficient, inexpensive, and sustainable.

A review on algae biosorption for the removal of hazardous pollutants from wastewater: Limiting factors, prospects and recommendations

Heavy metals, dyes and pharmaceutical pollutants in water environment are considered as serious threat to the human and animal health globally. Rapid development of industrialization and agricultural activities are the major source for eliminating the toxic pollutants into the aquatic environment. Several conventional treatment methods have been suggested for the removal of emerging contaminants from wastewater. Algal biosorption, among other strategies and techniques, is demonstrating to be a limited technical remedy that is more focused and inherently more efficient and helps remove dangerous contaminants from water sources. The different environmental effects of harmful contaminants, including heavy metals, dyes, and pharmaceutical chemicals, as well as their sources, were briefly compiled in the current review. This paper provides a comprehensive definition of the future possibilities in heavy compound decomposition by using algal technology, from aggregation to numerous biosorption procedures. Functionalized materials produced from algal sources were clearly proposed. This review further highlights the limiting factors of algal biosorption to eliminate the hazardous material. Finally, this study showed how the existence of algae indicates a potential, effective, affordable, and sustainable sorbent biomaterial for minimizing environmental pollution.

Ligninolytic enzyme activity and removal efficiency of pharmaceuticals in a water matrix by fungus Rhizopus sp. Isolated from cassava

Residual amounts of pharmaceutical compounds (PhCs) and by-products are continually released into surface water with effluents from conventional wastewater treatment plants (WWTPs). This study evaluated the ability of fungal isolate to remove selected PhCs [carbamazepine (CBZ), diclofenac (DCF) and ibuprofen (IBP)] from wastewater. The fungus used was Rhizopus sp. which was isolated from tuberous roots of cassava (Manihot esculenta). The isolate exhibited an important removal efficiency up to 100% and this was linked to ligninolytic enzymatic activity for lignin peroxidase (15.29 ± 2.69U/L) and manganese peroxidase (85.22 ± 4.26U/L), except laccase. This activity was optimum on day 9 of treatment. PhC metabolites were identified during the experiment revealing the existence of a biotransformation process catalysed by the isolated fungus. The disappearance of PhCs was attributed to their biosorption and biotransformation. However, it was not possible to establish a relationship between the ligninolytic enzymatic activity and the removal efficiency, which leads to the conclusion that there are other fungal metabolites which also play an important role in the biotransformation and biodegradation of the selected PhCs.

Improvements in Bioremediation Agents and Their Modified Strains in Mediating Environmental Pollution

Environmental pollution has been a significant concern around the globe as the release of toxic pollutants is associated with carcinogenic, mutagenic, and teratogenic impacts on living organisms. Since microorganisms have the natural potential to degrade toxic metabolites into nontoxic forms, an eco-friendly approach known as bioremediation has been used to tackle toxic-induced pollution. Bioremediation has three fundamental levels, i.e., natural attenuation, bio-augmentation, and biostimulation in which the synthetic biology approach has been lately utilized to enhance the conventional bioremediation techniques. Recently, a more advanced approach of programmable nucleases such as zinc finger nucleases, tale-like effector nucleases, and clustered regularly interspaced short palindromic repeats Cas is being employed to engineer several bacterial, fungal, and algal strains for targeted mutagenesis by knocking in and out specific genes which are involved in reconstructing the metabolic pathways of native microbes. These genetically engineered microorganisms possess heavy metal resistance, greater substrate range, enhanced enzymatic activity, and binding affinity which accelerate the biodegradation of toxic pollutants to environmentally safe levels. This review provides a comprehensive understanding of how we can correlate the novel genetics-based approaches employed to produce genetically engineered microorganisms to enhance the biodegradation of hazardous pollutants, hence, developing a clean and sustainable ecosystem.

Recent innovations and challenges in the eradication of emerging contaminants from aquatic systems

Presence of emerging pollutants (EPs), aka Micropollutants (MPs) in the freshwater environments is a severe threat to the environment and human beings. They include pharmaceuticals, insecticides, industrial chemicals, natural hormones, and personal care items and the pollutants are mostly present in wastewater generated from urbanization and increased industrial growth. Even concentrations as low as ngL^-1 or mgL^-1 have proven ecologically lethal to aquatic biota. For several years, the biodegradation of various Micropollutants (MPs) in aquatic ecosystems has been a significant area of research worldwide, with many chemical compounds being discovered in various water bodies. As aquatic biota spends most of their formative phases in polluted water, the impacts on aquatic biota are obvious, indicating that the environmental danger is substantial. In contrast, the impact of these contaminants on aquatic creatures and freshwater consumption is more subtle and manifests directly when disrupting the endocrine system. Research and development activities are expected to enable the development of ecologically sustainable, cost-effective, and efficient treatments for practical systems in the near future. Therefore, this review aims to understand recent emerging pollutants discovered and the available treatment technologies and suggest an innovative and cost-effective method to treat these EPs, which is sustainable and follows the circular bioeconomy.

Immobilization of Diatom Phaeodactylum tricornutum with Filamentous Fungi and Its Kinetics

Immobilizing microalgae cells in a hyphal matrix can simplify harvest while producing novel mycoalgae products with potential food, feed, biomaterial, and renewable energy applications; however, limited quantitative information to describe the process and its applicability under various conditions leads to difficulties in comparing across studies and scaling-up. Here, we demonstrate the immobilization of both active and heat-deactivated marine diatom Phaeodactylum tricornutum (UTEX 466) using different loadings of fungal pellets (Aspergillus sp.) and model the process through kinetics and equilibrium models. Active P. tricornutum cells were not required for the fungal-assisted immobilization process and the fungal isolate was able to immobilize more than its original mass of microalgae. The Freundlich isotherm model adequately described the equilibrium immobilization characteristics and indicated increased normalized algae immobilization (g algae removed/g fungi loaded) under low fungal pellet loadings. The kinetics of algae immobilization by the fungal pellets were found to be adequately modeled using both a pseudo-second order model and a model previously developed for fungal-assisted algae immobilization. These results provide new insights into the behavior and potential applications of fungal-assisted algae immobilization.

Review on rewiring of microalgal strategies for the heavy metal remediation - A metal specific logistics and tactics

Phycoremediation of heavy metals are gaining much attention and becoming an emerging practice for the metal removal in diverse environmental matrices. Still, the physicochemical state of metal polluted sites is often found to be complex and haphazard in nature due to the irregular discharge of wastes, that leads to the lack of conjecture on the application of microalgae for the metal bioremediation. Besides, the foresaid issues might be eventually ended up with futile effect to the polluted site. Therefore, this review is mainly focusing on interpretative assessment on pre-existing microalgal strategies and their merits and demerits for selected metal removal by microalgae through various process such as natural attenuation, nutritional amendment, chemical pretreatment, metal specific modification, immobilization and amalgamation, customization of genetic elements and integrative remediation approaches. Thus, this review provides the ideal knowledge for choosing an efficient metal remediation tactics based on the state of polluted environment. Also, this in-depth description would provide the speculative knowledge of counteractive action required for pass-over the barriers and obstacles during implementation. In addition, the most common metal removal mechanism of microalgae by adsorption was comparatively investigated with different metals through the principal component analysis by grouping various factor such as pH, temperature, initial metal concentration, adsorption capacity, removal efficiency, contact time in different microalgae. Conclusively, the suitable strategies for different heavy metals removal and addressing the complications along with their solution is comprehensively deliberated for metal removal mechanism in microalgae.

Fungal assisted bio-treatment of environmental pollutants with comprehensive emphasis on noxious heavy metals: Recent updates

In the present time of speedy developments and industrialization, heavy metals are being uncovered in aquatic environment and soil via refining, electroplating, processing, mining, metallurgical activities, dyeing and other several metallic and metal based industrial and synthetic activities. Heavy metals like lead (Pb), mercury (Hg), cadmium (Cd), arsenic (As), Zinc (Zn), Cobalt (Co), Iron (Fe), and many other are considered as seriously noxious and toxic for the aquatic environment, human, and other aquatic lives and have damaging influences. Such heavy metals, which are very tough to be degraded, can be managed by reducing their potential through various processes like removal, precipitation, oxidation-reduction, bio-sorption, recovery, bioaccumulation, bio-mineralization etc. Microbes are known as talented bio-agents for the heavy metals detoxification process and fungi are one of the cherished bio-sources that show noteworthy aptitude of heavy metal sorption and metal tolerance. Thus, the main objective of the authors was to come with a comprehensive review having methodological insights on the novel and recent results in the field of mycoremediation of heavy metals. This review significantly assesses the potential talent of fungi in heavy metal detoxification and thus, in environmental restoration. Many reported works, methodologies and mechanistic sights have been evaluated to explore the fungal-assisted heavy metal remediation. Herein, a compact and effectual discussion on the recent mycoremediation studies of organic pollutants like dyes, petroleum, pesticides, insecticides, herbicides, and pharmaceutical wastes have also been presented.

The emerging potential of natural and synthetic algae-based microbiomes for heavy metal removal and recovery from wastewaters

Heavy Metal (HM) bioremoval by microbes is a successful, environment-friendly technique, particularly at low concentrations of HMs. Studies using algae, bacteria, and fungi reveal promising capabilities in isolation and when used in consortia. Yet, few reviews have emphasized individual and collective HM removal rates and the associated mechanisms in natural or synthetic microbiomes. Besides discussing the limitations of conventional and synthetic biology approaches, this review underscores the utility of indigenous microbial taxon, i.e., algae, fungi, and bacteria, in HM removal with adsorption capacities and their synergistic role in microbiome-led studies. The detoxification mechanisms studied for certain HMs indicate distinctive removal pathways in each taxon which points to an enhanced effect when used as a microbiome. The role and higher efficacies of the designer microbiomes with complementing and mutualistic taxa are also considered, followed by recovery options for a circular bioeconomy. The citation network analysis further validates the multi-metal removal ability of microbiomes and the restricted capabilities of the individual counterparts. In precis, the study reemphasizes increased metal removal efficiencies of inter-taxon microbiomes and the mechanisms for synergistic and improved removal, eventually drawing attention to the benefits of ecological engineering approaches compared to other alternatives.

Literature Review: Evaluation of Drug Removal Techniques in Municipal and Hospital Wastewater

There are several techniques for the removal of pharmaceuticals (drugs) from wastewater; however, strengths and weaknesses have been observed in their elimination processes that limit their applicability. Therefore, we aimed to evaluate the best techniques for the removal of pharmaceuticals from municipal and hospital wastewater. For this, a non-experimental, descriptive, qualitative-quantitative design was used, corresponding to a systematic review without meta-analysis. Based on established inclusion and exclusion criteria, 31 open-access articles were selected from the Scopus, ProQuest, EBSCOhost, and ScienceDirect databases. The results showed that high concentrations of analgesics such as naproxen (1.37 mg/L) and antibiotics such as norfloxacin (0.561 mg/L) are frequently found in wastewater and that techniques such as reverse osmosis, ozonation, and activated sludge have the best removal efficiency, achieving values of 99%. It was concluded that reverse osmosis is one of the most efficient techniques for eliminating ofloxacin, sulfamethoxazole, carbamazepine, and diclofenac from municipal wastewater, with removal rates ranging from 96 to 99.9%, while for hospital wastewater the activated sludge technique proved to be efficient, eliminating analgesics and antibiotics in the range of 41-99%.

Biosorption Potential of Microbial and Residual Biomass of Saccharomyces pastorianus Immobilized in Calcium Alginate Matrix for Pharmaceuticals Removal from Aqueous Solutions

Two types of biosorbents, based on Saccharomyces pastorianus immobilized in calcium alginate, were studied for the removal of pharmaceuticals from aqueous solutions. Synthetized biocomposite materials were characterized chemically and morphologically, both before and after simulated biosorption. Ethacridine lactate (EL) was chosen as a target molecule. The process performance was interpreted as a function of initial solution pH, biosorbent dose, and initial pharmaceutical concentration. The results exhibited that the removal efficiencies were superior to 90% for both biosorbents, at the initial pH value of 4.0 and biosorbent dose of 2 g/L for all EL initial concentrations tested. Freundlich, Temkin, Hill, Redlich-Peterson, Sips, and Toth isotherms were used to describe the experimental results. The kinetic data were analyzed using kinetic models, such as pseudo-first order, pseudo-second order, Elovich, and Avrami, to determine the kinetic parameters and describe the transport mechanisms of EL from aqueous solution onto biosorbents. Among the tested equations, the best fit is ensured by the pseudo-second-order kinetics model for both biosorbents, with the correlation coefficient having values higher than 0.996. The many potential advantages and good biosorptive capacity of Saccharomyces pastorianus biomass immobilized in calcium alginate recommend these types of biocomposite materials for the removal of pharmaceuticals from aqueous solutions.

Pharmaceuticals in the Aquatic Environment: A Review on Eco-Toxicology and the Remediation Potential of Algae

The pollution of the aquatic environment has become a worldwide problem. The widespread use of pesticides, heavy metals and pharmaceuticals through anthropogenic activities has increased the emission of such contaminants into wastewater. Pharmaceuticals constitute a significant class of aquatic contaminants and can seriously threaten the health of non-target organisms. No strict legal regulations on the consumption and release of pharmaceuticals into water bodies have been implemented on a global scale. Different conventional wastewater treatments are not well-designed to remove emerging contaminants from wastewater with high efficiency. Therefore, particular attention has been paid to the phycoremediation technique, which seems to be a promising choice as a low-cost and environment-friendly wastewater treatment. This technique uses macro- or micro-algae for the removal or biotransformation of pollutants and is constantly being developed to cope with the issue of wastewater contamination. The aims of this review are: (i) to examine the occurrence of pharmaceuticals in water, and their toxicity on non-target organisms and to describe the inefficient conventional wastewater treatments; (ii) present cost-efficient algal-based techniques of contamination removal; (iii) to characterize types of algae cultivation systems; and (iv) to describe the challenges and advantages of phycoremediation.

Progress in microalgal mediated bioremediation systems for the removal of antibiotics and pharmaceuticals from wastewater

Worldwide demand for antibiotics and pharmaceutical products is continuously increasing for the control of disease and improvement of human health. Poor management and partial metabolism of these compounds result in the pollution of aquatic systems, leading to hazardous effects on flora, fauna, and ecosystems. In the past decade, the importance of microalgae in micropollutant removal has been widely reported. Microalgal systems are advantageous as their cultivation does not require additional nutrients: they can recover resources from wastewater and degrade antibiotics and pharmaceutical pollutants simultaneously. Bioadsorption, degradation, and accumulation are the main mechanisms involved in pollutant removal by microalgae. Integration of microalgae-mediated pollutant removal with other technologies, such as biodiesel, biochemical, and bioelectricity production, can make this technology more economical and efficient. This article summarizes the current scenario of antibiotic and pharmaceutical removal from wastewater using microalgae-mediated technologies.

Fluoxetine and Nutrients Removal from Aqueous Solutions by Phycoremediation

The tertiary treatment using microalgae offers an attractive alternative to the removal of low but relevant concentrations of pharmaceuticals from domestic wastewaters. The removal of fluoxetine from aqueous solutions by living and non-living (lyophilized) Chlorella vulgaris was assessed. The determination of the pH at the point of zero charge, Fourier transmittance infrared analysis, and scanning electron microscopy were performed to characterize the microalgae biomass. Kinetic and equilibrium experiments were performed. The pseudo-second-order model described the kinetics of fluoxetine. The corresponding kinetic constants indicated that biosorption was faster onto non-living biomass than onto living biomass. The equilibrium results showed that the systems followed the Langmuir isotherm model. The maximum capacity of living microalgae (1.9 ± 0.1 mg·g⁻¹) was slightly higher than the non-living microalgae (1.6 ± 0.2 mg·g⁻¹). Living Chlorella vulgaris, free and immobilized in calcium-alginate, were also used to remove fluoxetine and nutrients (nitrogen and phosphorus) from treated municipal wastewater in a batch system. In both experiments, fluoxetine was completely removed within six days. The total phosphorus (TP) and total nitrogen (TN) removal efficiencies achieved for free and immobilized cells were, null and 65.0 ± 0.1%, and 86.2 ± 0.1% and 81.8 ± 3.1, respectively.

A comprehensive review on current technologies for removal of endocrine disrupting chemicals from wastewaters

In the recent years, endocrine disrupting compounds (EDCs) has received increasing attention due to their significant toxic effects on human beings and wildlife by affecting their endocrine systems. As an important group of emerging pollutant, EDCs have been detected in various aquatic environments, including surface waters, groundwater, wastewater, runoff, and landfill leachates. Their removal from water resources has also been an emerging concern considering growing population as well as reducing access to fresh water resources. EDC removal from wastewaters is highly dependent on physicochemical properties of the given EDCs present in each wastewater types as well as various aquatic environments. Due to chemical, physical and physicochemical diversities in these parameters, variety of technologies consisting of physical, biological, electrochemical, and chemical processes have been developed for their removal. This review highlights that the effectiveness of EDC removal is highly dependent of selecting the appropriate technology; which decision is made upon a full wastewater chemical characterization. This review aims to provide a comprehensive perspective about all the current technologies used for EDCs removal from various aquatic matrices along with rising challenges such as the antimicrobial resistance gene transfer during EDC treatment.

A comprehensive review on the use of algal-bacterial systems for wastewater treatment with emphasis on nutrient and micropollutant removal

The scarcity of water resources and environmental pollution have highlighted the need for sustainable wastewater treatment. Existing conventional treatment systems are energy-intensive and not always able to meet stringent disposal standards. Recently, algal-bacterial systems have emerged as environmentally friendly sustainable processes for wastewater treatment and resource recovery. The algal-bacterial systems work on the principle of the symbiotic relationship between algae and bacteria. This paper comprehensively discusses the most recent studies on algal-bacterial systems for wastewater treatment, factors affecting the treatment, and aspects of resource recovery from the biomass. The algal-bacterial interaction includes cell-to-cell communication, substrate exchange, and horizontal gene transfer. The quorum sensing (QS) molecules and their effects on algal-bacterial interactions are briefly discussed. The effect of the factors such as pH, temperature, C/N/P ratio, light intensity, and external aeration on the algal-bacterial systems have been discussed. An overview of the modeling aspects of algal-bacterial systems has been provided. The algal-bacterial systems have the potential for removing micropollutants because of the diverse possible interactions between algae-bacteria. The removal mechanisms of micropollutants - sorption, biodegradation, and photodegradation, have been reviewed. The harvesting methods and resource recovery aspects have been presented. The major challenges associated with algal-bacterial systems for real scale implementation and future perspectives have been discussed. Integrating wastewater treatment with the algal biorefinery concept reduces the overall waste component in a wastewater treatment system by converting the biomass into a useful product, resulting in a sustainable system that contributes to the circular bioeconomy.

Microalgal drugs: A promising therapeutic reserve for the future

Over the decades, a variety of chemically synthesized drugs are being used to cure existing diseases but often these drugs could not be effectively employed for the treatment of serious and newly emerging diseases. Fortunately, in nature there occurs immense treasure of plants and microorganisms which are living jewels with respect to their richness of medically important metabolites of high value. Hence, amongst the existing microorganism(s), the marine world offers a plethora of biological entities that can contribute to alleviate numerous human ailments. Algae are one such photosynthetic microorganism found in both marine as well as fresh water which are rich source of metabolites known for their nutrient content and health benefits. Various algal species like Haematococcus, Diatoms, Griffithsia, Chlorella, Spirulina, Ulva, etc. have been identified and isolated to produce biologically active and pharmaceutically important high value compounds like astaxanthin, fucoxanthin, sulphur polysaccharides mainly galactose, rhamnose, xylose, fucose etc., which show antimicrobial, antifungal, anti-cancer, and antiviral activities. However, the production of either of these bio compounds is favored under conditions of stress. This review gives detailed information on various nutraceutical metabolites extracted from algae. Additionally focus has been made on the role of these bio compounds extracted from algae especially sulphur polysaccharides to treat several diseases with prospective treatment for SARS-CoV-2. Lastly it covers the knowledge gaps and future perspectives in this area of research.

Enhanced removal efficiency of sulfamethoxazole by acclimated microalgae: Tolerant mechanism, and transformation products and pathways

This study utilized sulfamethoxazole (SMX) acclimatization to enhance the tolerance and biodegradation capacity of Chlorella vulgaris. Compared to wild C. vulgaris, the growth inhibition and oxidative damage induced by SMX evidently decreased in acclimated C. vulgaris, and meanwhile photosynthetic and antioxidant activities were significantly promoted. The physiological analyses with the aid of principal component analysis revealed the increase of catalase and glutathione reductase activities was the critical tolerant mechanism of acclimated C. vulgaris. As the consequence, the acclimated C. vulgaris exhibited enhanced efficiency and (pseudo-first-order) kinetic rate for removal of SMX. The distribution analysis of residual SMX demonstrated the biodegradation was the major removal mechanism of SMX by C. vulgaris, while bioadsorption and bioaccumulation made pimping contributions. During the degradation process of SMX, nine transformation products (TPs) were identified. Based on the identified TPs, a possible transformation pathway was proposed.

Fluoxetine Removal from Aqueous Solutions Using a Lignocellulosic Substrate Colonized by the White-Rot Fungus Pleurotus ostreatus

One of the main challenges in both the design of new wastewater treatment plants and the expansion and improvement of existing ones is the removal of emerging pollutants. Therefore, the search for economic and sustainable treatments is needed to enhance the removal of pharmaceuticals. The potential of a lignocellulosic substrate colonized by Pleurotus ostreatus, a waste from mushroom production, to remove fluoxetine from aqueous solutions was studied. Batch assays were performed to remove 600 µg∙L⁻¹ fluoxetine from aqueous solutions using the colonized mushroom substrate (CMS) and crude enzyme extracts. The removal efficiencies achieved were, respectively, ≥83.1% and 19.6% in 10 min. Batch assays with sterilized CMS and 1-aminobenzotriazole (to inhibit cytochrome P450 enzymes) showed that the higher removal efficiencies achieved in the CMS assays may be attributed to the synergistic contribution of biosorption onto the CMS and lignin modifying enzymes activity, namely laccase activity. A column assay was performed with the CMS, fed with 750 µg∙L⁻¹ fluoxetine aqueous solution. The removal efficiency was 100% during 30 min, decreasing to a final value of 70% after 8 h of operation. The results suggested that CMS can be a promising eco-friendly alternative to remove fluoxetine from aqueous solutions.

Pharmaceuticals and personal care products in aquatic environments and their removal by algae-based systems

The consumption of pharmaceuticals and personal care products (PPCPs) has been widely increasing, yet up to 90-95% of PPCPs consumed by human are excreted unmetabolized. Moreover, the most of PPCPs cannot be fully removed by wastewater treatment plants (WWTPs), which release PPCPs to natural water bodies, affecting aquatic ecosystems and potentially humans. This study sought to review the occurrence of PPCPs in natural water bodies globally, and assess the effects of important factors on the fluxes of pollutants into receiving waterways. The highest ibuprofen concentration (3738 ng/L) in tap water was reported in Nigeria, and the highest naproxen concentration (37,700 ng/L) was reported in groundwater wells in Penn State, USA. Moreover, the PPCPs have affected aquatic organisms such as fish. For instance, up to 24.4 × 10³ ng/g of atenolol was detected in P. lineatus. Amongst different technologies to eliminate PPCPs, algae-based systems are environmentally friendly and effective because of the photosynthetic ability of algae to absorb CO₂ and their flexibility to grow in different wastewater. Up to 99% of triclosan and less than 10% of trimethoprim were removed by Nannochloris sp., green algae. Moreover, variable concentrations of PPCPs might adversely affect the growth and production of algae. The exposure of algae to high concentrations of PPCPs can reduce the content of chlorophyll and protein due to producing reactive oxygen species (ROS), and affecting expression of some genes in chlorophyll (rbcL, psbA, psaB and psbc).

Algae-mediated antibiotic wastewater treatment: A critical review

The existence of continually increasing concentrations of antibiotics in the environment is a serious potential hazard due to their toxicity and persistence. Unfortunately, conventional treatment techniques, such as those utilized in wastewater treatment plants, are not efficient for the treatment of wastewater containing antibiotic. Recently, algae-based technologies have been found to be a sustainable and promising technique for antibiotic removal. Therefore, this review aims to provide a critical summary of algae-based technologies and their important role in antibiotic wastewater treatment. Algal removal mechanisms including bioadsorption, bioaccumulation, and biodegradation are discussed in detail, with using algae-bacteria consortia for antibiotic treatment, integration of algae with other microorganisms (fungi and multiple algal species), hybrid algae-based treatment and constructed wetlands, and the factors affecting algal antibiotic degradation comprehensively described and assessed. In addition, the use of algae as a precursor for the production of biochar is highlighted, along with the modification of biochar with other materials to improve its antibiotic removal capacity and hybrid algae-based treatment with advanced oxidation processes. Furthermore, recent novel approaches for enhancing antibiotic removal, such as the use of genetic engineering to enhance the antibiotic degradation capacity of algae and the integration of algal antibiotic removal with bioelectrochemical systems are discussed. Finally, some based on the critical review, key future research perspectives are proposed. Overall, this review systematically presents the current progress in algae-mediated antibiotic removal technologies, providing some novel insights for improved alleviation of antibiotic pollution in aquatic environments.

Algae bioprocess to deal with cosmetic chemical pollutants in natural ecosystems: A comprehensive review

Elevated demand and extensive exploitation of cosmetics in day-to-day life have hiked up its industrial productions worldwide. Organic and inorganic chemicals like parabens, phthalates, sulfates, and so forth are being applied as constituents towards the formulations, which tend to be the mainspring ecological complication due to their enduring nature and accumulation properties in various sections of the ecosystem. These cosmetic chemicals get accrued into the terrestrial and aquatic systems on account of various anthropogenic activities involving agricultural runoff, industrial discharge, and domestic effluents. Recently, the use of microbes for remediating persistent cosmetic chemicals has gained immense interest. Among different forms of the microbial community being applied as an environmental beneficiary, algae play a vital role in both terrestrial and aquatic ecosystems by their biologically beneficial metabolites and molecules, resulting in the biobenign and efficacious consequences. The use of various bacterial, fungal, and higher plant species has been studied intensely for their bioremediation elements. The bioremediating property of the algal cells through biosorption, bioassimilation, biotransformation, and biodegradation has made it favorable for the removal of persistent and toxic pollutants from the environment. However, the research investigation concerned with the bioremediation potential of the algal kingdom is limited. This review summarizes and provides updated and comprehensive insights into the potential remediation capabilities of algal species against ecologically hazardous pollutants concerning cosmetic chemicals.

Algae-mediated processes for the treatment of antiretroviral drugs in wastewater: Prospects and challenges

The prevalence of pharmaceuticals (PCs), especially antiretroviral (ARV) drugs in various aquatic ecosystems has been expansively reported, wherein wastewater treatment plants (WWTPs) are identified as the primary point source. Consequently, the occurrence, ecotoxicity and treatment of ARV drugs in WWTPs have drawn much attention in recent years. Numerous studies have shown that the widely employed activated sludge-based WWTPs are incapable of removing ARV drugs efficiently from wastewater. Recently, algae-based wastewater treatment processes have shown promising results in PCs removal from wastewater, either completely or partially, through different processes such as biosorption, bioaccumulation, and intra-/inter-cellular degradation. Algal species have also shown to tolerate high concentrations of ARV drugs than the reported concentrations in the environmental matrices. In this review, emphasis has been given on discussing the current status of the occurrence of ARV drugs in the aquatic environment and WWTPs. Besides, the current trends and future perspectives of PCs removal by algae are critically reviewed and discussed. The potential pathways and mechanisms of ARV drugs removal by algae have also been discussed.

Evaluation of the Potential of Sewage Sludge Mycobiome to Degrade High Diclofenac and Bisphenol-A Concentrations

One of the most challenging environmental threats of the last two decades is the effects of emerging pollutants (EPs) such as pharmaceutical compounds or industrial additives. Diclofenac and bisphenol A have regularly been found in wastewater treatment plants, and in soils and water bodies because of their extensive usage and their recalcitrant nature. Due to the fact of this adversity, fungal communities play an important role in being able to safely degrade EPs. In this work, we obtained a sewage sludge sample to study both the culturable and non-culturable microorganisms through DNA extraction and massive sequencing using Illumina MiSeq techniques, with the goal of finding degraders adapted to polluted environments. Afterward, degradation experiments on diclofenac and bisphenol A were performed with the best fungal degraders. The analysis of bacterial diversity showed that Dethiosulfovibrionaceae, Comamonadaceae, and Isosphaeraceae were the most abundant families. A predominance of Ascomycota fungi in the culturable and non-culturable population was also detected. Species such as Talaromyces gossypii, Syncephalastrum monosporum, Aspergillus tabacinus, and Talaromyces verruculosus had remarkable degradation rates, up to 80% of diclofenac and bisphenol A was fully degraded. These results highlight the importance of characterizing autochthonous microorganisms and the possibility of selecting native fungal microorganisms to develop tailored biotransformation technologies for EPs.

Fate of active pharmaceutical ingredients in a northern high-rate algal pond fed with municipal wastewater

Active pharmaceutical ingredients (APIs) are vital to human health and welfare, but following therapeutic use, they may pose a potential ecological risk if discharged into the environment. Today's conventional municipal wastewater treatment plants are not designed to remove APIs specifically, and various techniques, preferably cost-effective and environmentally friendly, are being developed and evaluated. Microalgae-based treatment of wastewater is a sustainable and low-cost approach to remove nutrients and emerging contaminants. In this study, a North Sweden high-rate algal pond (HRAP) using municipal untreated wastewater as medium, was investigated in terms of API distribution and fate. Three six-day batches were prepared during 18 days and a total of 36 APIs were quantified within the HRAP of which 14 were removed from the aqueous phase above 50% and seven removed above 90% of their initial concentrations. Twelve APIs of a hydrophobic nature were mostly associated with the algal biomass that was harvested at the end of each batch. HRAPs treatment successfully removed 69% of studied APIs (25 of 36 studied) in six day time. The distribution of various APIs between the aqueous phase and biomass suggested that several removal mechanisms may occur, such as hydrophobicity driven removal, passive biosorption and active bioaccumulation.

Distinct mechanisms underlying the assembly of microeukaryotic generalists and specialists in an anthropogenically impacted river

Microeukaryotic communities are sensitive to environmental changes; and are considered essential for microbial food webs and biogeochemical cycles. Therefore, understanding the community responses of microeukaryotes to environmental changes is of great ecological significance. Very little is known about the assembly mechanisms underlying the microeukaryotic communities, especially for the key ecological groups (e.g., habitat generalists/specialists) in the riverine ecosystems. Here, we employed 18S rDNA amplicon sequencing to study the assembly processes governing the microeukaryotic communities and their habitat generalists and specialists across three hydrological seasons in a subtropical river in China. The results showed that deterministic and stochastic processes jointly shaped the microeukaryotic communities, where the relative importance of stochastic processes decreased in the following order: wet > normal > dry seasons. However, deterministic processes played more important role in shaping the microeukaryotic communities than those of prokaryotes. Meanwhile, stochastic and deterministic processes were responsible for structuring the microeukaryotic habitat generalists and specialists, respectively. Generally, the pure effects of physicochemical factors on the microeukaryotic communities and their key ecological groups were ~ 1.7 folds than those of the micropollutants. However, several micropollutants (e.g., acetaminophen, benzophenone-3, bisphenol A, sulfadiazine, triclocarban and triclosan) were found to have a strong effect on the habitat specialists. Altogether, we suggested that the ecological responses of the riverine microeukaryotes to micropollutants may vary among species due to the intrinsic differences in their environmental plasticity.

Biosorption of dicloxacillin from pharmaceutical waste water using tannin from Indian almond leaf: Kinetic and equilibrium studies

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The maximum adsorption capacity was 86.93 %.

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Experimental data were in agreement with pseudo-second-order kinetics.

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Experimental data were followed Langmuir isotherm model.

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Biosorption of dicloxacilin onto T. catappa L. biomass is possible, spontaneous and exothermic process.

This study focused on the use of Indian almond leaf biomass, a local plant widely found in Thailand, on removal of dicloxacillin from pharmaceutical waste water by biosorption. The biosorption characteristics of dicloxacillin were investigated in terms of equilibrium, kinetics and thermodynamics. Optimum biosorption conditions were determined from pH, initial dicloxacillin concentration, biomass dosage, contact time, and temperature. The maximum adsorption capacity was 86.93 % (pH 6.0, 0.1 g/L biomass, dicloxacillin concentration 20 mg/L, contact time 24 h, temperature 283.15 K). The thermodynamic parameters (298.15 K), free energy change, enthalpy change and entropy change were -3475.79 J/mol, −25.36 kJ/mol, and −73.40 J/mol/K, respectively. The best interpretation for the experimental data was given by the Langmuir isotherm with correlation coefficient of 0.965. The results were found to tie in well with pseudo-second-order kinetics. Considering the cost-effectiveness, Indian almond leaf biomass is considered to be suitable to remove dicloxacillin from pharmaceutical waste water.

Chemically Modified Biosorbents and Their Role in the Removal of Emerging Pharmaceutical Waste in the Water System

Presence of pharmaceutically active compounds (PACs) as emerging contaminants in water is a major concern. Recent reports have confirmed the presence of PACs in natural and wastewater systems, which have caused several problems indicating the urgent need for their removal. The current review evaluates the role of chemically modified biosorbents in the removal of PACs in water. Reported biosorbents include plant and animal solid waste, microorganisms and bio-composite. Bio-composites exhibited better prospects when compared with other biosorbents. Types of chemical treatment reported include acid, alkaline, solvent extraction, metal salt impregnation and surface grafting, with alkaline treatment exhibiting better results when compared with other treatments. The biosorption processes mostly obeyed the pseudo-second-order model and the Langmuir isotherm model in a process described mainly by ionic interaction. Desorption and regeneration capacity are very important in selecting an appropriate biosorbent for the biosorption process. Depending on the type of biosorbent, the cost of water treatment per million liters of water was estimated as US $10–US $200, which presents biosorption as a cheap process compared to other known water treatment processes. However, there is a need to conduct large-scale studies on the biosorption process for removing PACs in water.