The pervasive issue of lead contamination in water systems necessitates the development of advanced and sustainable remediation methodologies. Powdered activated carbon synthesized from Pinus roxburghii has been meticulously evaluated as a high-performance capture medium to remove sequestration of lead ions from aqueous systems through batch adsorption studies. These adsorption dynamics were optimized by Response Surface Methodology integrated with Central Composite Design, enabling precise calibration of crucial influential factors such as pH, contact time, and adsorbent dosage. Morphological analysis conducted using Scanning Electron Microscopy confirmed a highly porous structure, while Fourier Transform Infrared Spectroscopy identified functional groups, such as hydroxyl groups coupled with carbonyl groups, which exhibit strong metal affinity. Under optimal conditions, a pH of 8.2, a time of 140 min, and an adsorbent dosage of 0.03 g/L resulted in a maximum lead removal efficiency of 99.86%. Validation trials substantiated the reproducibility of the process, yielding a marginally diminished efficiency of 98.62 +/- 1.24%. The integration of RSM not only validated the statistical significance of the experimental outcomes but also reinforced the predictive accuracy. This study demonstrates the critical interplay of adsorption parameters and highlights the physicochemical properties of Pinus roxburghii-based activated carbon, emphasizing its potential for advanced water purification processes.

This study focused on synthesizing a low-cost adsorbent via a unique two-step solvothermal slow pyrolysis of Drepanostachyum falcatum plant biomass. It evaluated its adsorption capabilities for removing various textile dyes, including methylene blue (MB), basic fuchsin (BF), and methyl orange (MO), from aqueous solutions. Under conventional and ultrasound-assisted conditions, the adsorption performance was assessed for single, binary, and ternary dye systems. Comprehensive investigations examined the effects of environmental factors such as temperature, pH, humic acid, and interfering ions on adsorption. The findings revealed that ultrasonication significantly accelerated the adsorption process, making it up to six times faster than classical adsorption methods, and equilibrium was reached in one-tenth the time required without ultrasound. The experimental data best fit the pseudo-second-order kinetics model, indicating that chemisorption was the dominant adsorption mechanism. Additionally, the Freundlich isotherm suggested multilayer sorption on the biochar surface. Maximum adsorption capacities under ultrasound were found to be 139.34 mg/g for MB, 75.09 mg/g for MO, and 98.13 mg/g for BF dyes, with a higher affinity observed for cationic dyes compared to anionic dyes. The study provides insights into an efficient, novel synthesis method for converting waste biomass into a valuable adsorbent for dye removal. It also highlights the role of ultrasound in enhancing physicochemical properties, facilitating improved mass transfer, and promoting better interaction between the dyes and the adsorbent.

The worldwide detection of pharmaceutically active compounds in surface water, sub-surface water, and wastewater has become a global concern due to their widespread damaging effects on human and aquatic lives. This study aims to elucidate the role of adsorption techniques, specifically conventional stirring, and ultrasonication, in enhancing the adsorption efficiency of nanostructured hypercrosslinked polymers (HCPs) to remove potential pharmaceutical compounds from water. Here, we have employed a triptycene (THCP, SBET: 2288 m2/g and) -based porous organic polymer (POP) fabricated via a solvent knitting approach and postsynthetically functionalized with sulfonic acid groups to obtain sulfonated POP (STHCP) with a high specific surface area of 1150 m2/g. The adsorption studies showed promising uptake capacities of 591, 349, and 287 mg/ g for diclofenac (DCF), carbamazepine (CBZ), and caffeine (CAF), respectively, through ultrasonication-assisted technique. The experimental data fitted well with the Langmuir adsorption isotherm and pseudo-second-order adsorption model. Moreover, the adsorbent showed reusability for up to 10 cycles without a significant drop in the sorption capacity. Therefore, the prepared STHCP can be a potential adsorbent for efficiently removing pharmaceuticals from water.

Enzymes are playing a central role in many industrial processes like never before. This is mainly due to the significant benefits offered by biocatalysis in terms of moderate reaction conditions and specificity. However, while moving from bench to industrial scale, many small hurdles acquire a significant dimension. For instance, the problem of enzyme recovery, sensitivity to reaction conditions, and product recovery. β-galactosidases, which are essential enzymes in the food industry, are no exception to this. Fortunately, the strategies used in overcoming the challenges faced in the industrial scale-up and taming of other enzymes have been effective in β-galactosidases as well. As advances in material sciences are witnessed, enzyme immobilization technologies also see a revamp as scientists try to make the new matrices work for enzymes. Thus enzyme immobilization is an ever-evolving field necessitating frequent updates.

Even though water covers 75% of the earth's surface, only 0.0067% of it is available for human use. These figures continue to deteriorate as the world's population grows, resulting in an increase in the amount of waste created every year. Worldwide, the desire for clean and safe water has always been a major concern. The pursuit of efficient materials for environmental remediation is a critical scientific and technological concern. Carbon-based materials (CBM) have unique electrical, mechanical, and physicochemical properties, making them ideal for use as environmental adsorbents, sensors, membranes, and catalysts. Basically, CBM includes activated carbon, carbon nanofibre, biochar, carbon aerogel, graphene, carbon nanotubes, and so on. These materials can easily be engineered and functionalized, depending on the chemical nature of the target contaminants, and shows great efficiency towards the removal of hazardous materials. Carbon-based nanocomposites (CBNC) play a vital role in water treatment and environmental remediation due to their higher adsorption capacity, improved permeation, porous nature, and selectivity towards pollutants. This book chapter discusses the effective employment of CBNCs, including their future prospects in the field of water purification for the removal of textile dyes, volatile organic substances, toxic metals, oil, and biological contaminants.

EDITORIAL article Front. Microbiol., 22 August 2023Sec. Extreme Microbiology Volume 14 - 2023 | https://doi.org/10.3389/fmicb.2023.1252921

Harnessing graphene sheets' large surface area, catalytic effect, adsorption capacity, and reactivity, its use in composites for water treatment is on the rise. With ever-increasing newer pollutants in wastewater streams, treatment challenges are huge. Additionally, water scarcity puts an enormous demand on researchers to develop an integrated efficient system for desalination and wastewater purification. Can graphene-based composites and membranes meet water desalination and purification challenges? In this review, we provide a comprehensive report on the current graphene-based composites and membrane research. We laid out a systematic interrogation of present water purification techniques including desalination, shedding light on the prominent techniques that use graphene-based composites and their membranes. Not only are the fundamentals of the water purification mechanism, aspects of filtration device fabrication, and structural alteration parameters elaborated but how conditions affecting water filtration and use of eco-friendly graphene-based evaporators are emphasized. We also discuss underlying commercial aspects relating to the scale-up of the water treatment issues and highlight promising advances. Graphene's use provides cost-effectiveness and sustainability which are keys to its success. Our overall aim has been to connect the dots among the challenges of existing techniques, processability, scalability of graphene-based composites, and membranes for desalination and water purification methodologies.

The rapidly growing population has resulted in increased water demand and generation of high volume of solid wastes. Both excess solid waste and poor water reuse efficiency primarily result from improper management. Accordingly, to reduce the associated environmental burdens, the utilization of waste-derived material for water treatment can be considered as a sustainable approach. The current chapter aims to provide a holistic approach to solid waste management by generating value-added materials and their potential application for water pollution abatement. Different classes of waste, including agriculture, industrial, and electronic, and their possible activation methods are discussed. Also, the potential applications of such waste-derived products in different water treatment techniques, such as adsorption, catalysis, and electrochemical application, are detailed. Overall, the possibilities of utilizing waste to derive value-added products that can be employed for pollution abatement of contaminated water and achieve circular economic concepts are reviewed.

We report here the whole-genome sequence of β-lactamase-producing bacteria Bacillus tropicus EMB20. The genome sequence of Bacillus tropicus EMB20 has a size of 5.8 Mb (G + C content of 35.52

Herewith, we demonstrate a novel top-down approach for the cost-effective consecutive synthesis of 2D/3D graphene-based materials (GBM) from the extract and fibrous parts of the Drepanostachyum falcatum plant, using a two-stage thermal approach. At low temperature (150 °C), the extract of the D. falcatum showed the formation of a fluorescent 2D skeleton of the GBM i.e., metal-doped graphene oxide sheets (MDGOs) in presence of ethanol. On the other hand, the pyrolysis (∼300 °C) of the fibrous part showed the formation of a 3D skeleton of the graphene nanoribbons (GNR) in the N2 atmosphere. The presence of extensive π-π conjugated interactions with oxidative functional moieties in 2D-MDGOs is responsible for their blue fluorescent nature under UV irradiation at 365 nm. Meanwhile, 2D-MDGOs show excellent potential as a bio-imaging probe for non-tumorigenic prostate epithelial RWPE-1 cells. However, the very low cytotoxicity of 2D-MDGOs played a crucial role in upholding their bio-imaging potential. Simultaneously, the hydrophobic nature of 3D-GNR showed better adsorption towards the organic pollutants (dye) from the aqueous phase. The adsorption phenomenon of 3D-GNR was very fast and effective towards the removal of methylene blue (MB). Moreover, the Langmuir adsorption capacity for MB dye was found to be 31.94 mg/gm. This is the first time we are reporting the dual synthesis of 2D and 3D GBMs simultaneously, with different applicative potentials. Further, noticeable and in-depth observations were made for studying the reaction kinetics of the reaction to find a formal analytical connection between productivity, adsorptive, and applicability of 3D-GNR. Moreover, the market-based-cost analysis showed the huge industrial potential of these materials, which also make them inevitable and promising candidates for futuristic growth in their respective application in water purification.

On a global scale, food waste generation has set an alarming signal demanding its proper management and utilization. The present study investigates different types of bakery wastes used as a source of the high amount of reducing sugars for lactic acid production. As a result, bread waste (BW) containing 598 mg, reducing sugars/g waste was used for lactic acid production from several lactic acid bacteria (LAB). Out of these, SKL-9 (Lactobacillus paracasei), SKL-11 (Lactobacillus paracasei), and SKL-21 (Lactobacillus paracasei) were found to produce 53 mg/g BW (26.4 g/L), 56 mg/g BW (28 g/L), and 54 mg/g BW (27 g/L) of lactic acid, respectively under simultaneous saccharification and fermentation conditions. The selected strains were further tested for simultaneous saccharification and solid state fermentation (SSF) under semi-sterile conditions yielding 212, 223, and 250 mg/g BW of lactic acid by SKL-9, SKL-11, and SKL-21, respectively. Furthermore, the lactic acid produced was purified by employing the phase partitioning method giving a high recovery of 85%. Thus, the current approach is promising for the valorization of bakery waste into value-added lactic acid in an inexpensive one-pot process.

Solvent tolerance is a novel trait among halotolerant bacteria and their enzymes. However, the solvent response mechanisms in Gram-positive bacteria remain less investigated. The Exiguobacterium indicum (TBG-PICH-001) was isolated from the sediment of Pichavaram estuary. It possessed halotolerance and could prove to be a suitable candidate for solvent tolerance studies. The present study extensively explores possible cellular mechanisms in a Gram-positive bacterium when exposed to the organic solvents. The isolate was highly tolerant towards hydrophobic solvents with high log P value such as tetradecane, dodecane, decane compared to the other hydrophobic solvents having low log P value, viz. octane, heptane, isooctane, and hexane. The electron micrographs showed less conspicuous differences in the bacterial cell membrane exposed to highly hydrophobic organic solvents. In contrast, anomalous cell aggregation and cell membrane disorganization was observed in the presence of comparatively less hydrophobic solvents. The spectroscopic assay for cell permeability and viability advocated the toxic effects of the solvents on the cells and their corresponding adaptability. Additionally, the microbe produced a high yield of alkaline protease (900 U/mL) in the presence of hydrophobic solvents. Such solvent stable proteases could find applications in solvent-mediated biosynthesis of peptides, while the solvent stable bacterial isolate might be an efficient biosystem for such bioprocesses. The significant level of cell tolerance could provide the response mechanism insights, while stable protease yield offers the cost-effective development of bioprocesses through non-aqueous enzymology and whole-cell bio-transformations.

Antimicrobial resistance (AMR) is one of the serious global public health threats that require immediate action. With the emergence of new resistance mechanisms in infection-causing microorganisms such as bacteria, fungi, and viruses, AMR threatens the effective prevention and treatment of diseases caused by them. This has resulted in prolonged illness, disability, and death. It has been predicted that AMR will lead to over ten million deaths by 2050. The rapid spread of multidrug-resistant bacteria is also causing old antibiotics to become ineffective. Among the diverse factors contributing to AMR, intrinsic biofilm development has been highlighted as an essential contributing facet. Moreover, biofilm-derived antibiotic tolerance leads to serious recurrent chronic infections. Therefore, the discovery of novel bioactive molecules is a potential solution that can help combat AMR. To achieve this, sustained mining of novel antimicrobial leads from actinobacteria, particularly marine actinobacteria, can be a promising strategy. Given their vast diversity and different habitats, the extraordinary capacity of actinobacteria can be tapped to synthesize new antibiotics or bioactive molecules for biofilm inhibition. Advanced screening strategies and novel approaches in the field of modern biochemical and molecular biology can be used to detect such new compounds. In view of this, the present review focuses on understanding some of the recent strategies to inhibit biofilm formation and explores the potential role of marine actinobacteria as sources of novel antibiotics and biofilm inhibitor molecules.

Purified preparations of enzymes are requisite for their application as well as decoding their basic characteristics and mechanisms. The chapter presents the purification protocols employed to purify a range of industrially useful enzymes mainly sourced from extremophiles (solvent-tolerant and halophilic microbes). Single-step Phenyl Sepharose 6 Fast Flow hydrophobic interaction chromatography for extremophilic enzymes and affinity precipitation by alginate for carbohydrate-active enzymes were adopted by us. A single-step purification protocol is economical, and better enzyme recovery is obtained. Pseudomonas aeruginosa PseA, our laboratory isolate, turned out to be a versatile solvent-tolerant microbe. Three potential enzymes, protease, lipase, and aminopeptidase, were produced, purified, and characterized from it and was potentiated for use in nonaqueous enzymology. Proteases, lipase, and amylase from halophiles were also purified and characterized. Halophilic enzymes are industrially desirable as, in addition to salt-stability other polyextremophilic properties are found in these enzymes. The experiences gained by purifying these enzymes will come in handy for developing successful purification procedures for other proteins.