Hydrochar-nanoparticle integration for arsenic removal from wastewater: Challenges, possible solutions, and future horizon.

Arsenic (As) contamination poses a significant threat to human health, ecosystems, and agriculture, with levels ranging from 12 to 75% attributed to mine waste and stream sediments. This naturally element is abundant in Earth's crust and gets released into the environment through mining and rock processing, causing ≈363 million people to depend on As-contaminated groundwater. To combat this issue, introducing a sustainable hydrochar system has achieved a remarkable removal efficiency of over 92% for arsenic through adsorption. This comprehensive review presents an overview of As contamination in the environment, with a specific focus on its impact on drinking water and wastewater. It delves into the far-reaching effects of As on human health, ecosystems, aquatic systems, and agriculture, while also exploring the effectiveness of existing As treatment systems. Additionally, the study examines the potential of hydrochar as an efficient adsorbent for As removal from water/wastewater, along with other relevant adsorbents and biomass-based preparations of hydrochar. Notably, the fusion of hydrochar with nanoparticle-centric approaches presents a highly promising and environmentally friendly solution for achieving the removal of As from wastewater, exceeding >99% efficiency. This innovative approach holds immense potential for advancing the realms of green chemistry and environmental restoration. Various challenges associated with As contamination and treatment are highlighted, and proposed solutions are discussed. The review emphasizes the urgent need to advance treatment technologies, improve monitoring methods, and enhance regulatory frameworks. Looking outlook, the article underscores the importance of fostering research efforts, raising public awareness, and fostering interdisciplinary collaboration to address this critical environmental issue. Such efforts are vital for UN Sustainable Development Goals, especially clean water and sanitation (Goal 6) and climate action (Goal 13), crucial for global sustainability.

Divulging the anti-acetylcholinesterase activity of Colletotrichum lentis strain KU1 extract as sustainable AChE active site inhibitors.

Alzheimer's disease (AD), also called senile dementia is a neurodegenerative disease seen commonly in the elderly and is characterised by the formation of ß-amyloid plaques and neurofibrillary tangles (NFT). Though a complete understanding of the disease is lacking, recent studies showed the role of the enzyme acetylcholinesterase (AChE) in pathogenesis. Finding new lead compounds from natural sources has always been a quest for researchers. Endophytic fungi are a set of microbes that reside within plants without causing any harm. This study focuses on screening endophytes for the production of active acetylcholinesterase inhibitors. Five endophytic fungi were isolated from Catharanthus roseus and screened for AChE inhibitory activity. Three isolates were found to inhibit AChE inhibitory activity and were distinguished based on molecular and microscopic methods. The mycelial extract was taken for the bioassay-guided column chromatography and TLC was performed on the active fraction. The GC-MS and NMR analysis identified the active compounds in the extract as 9-hexadecen-1-ol and erucamide. Molecular docking studies revealed that the compounds are thermodynamically feasible and have significant glide scores. Computational studies revealed that the hydroxyl group of 9-hexadecen-1-ol forms a hydrogen bond with Ser 293 in the active site of AChE, whereas the active site interactions were predominantly hydrophobic in the case of erucamide and are reflected in AChE inhibition assays.

Molecular modeling study of tectoquinone and acteoside from Tectona grandis linn: a new SARS-CoV-2 main protease inhibitor against COVID-19.

Coronavirus disease 2019 (COVID-19), a highly contagious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has drastically changed the lifestyle of people around the globe. Due to the lack of specific and effective antiviral drugs, transmission of the disease increases exponentially and makes it more serious and harder to control. Drugs that were assumed to be effective against COVID-19 have failed in various stages of clinical trials and this made the scientific community more disappointed. But, the race of researchers for developing new and effective antiviral to stop the disease progression still continues and our work is one among them. This study is an attempt to analyze the action of Tectoquinone and Acteoside; an important phytocompound, on SARS-CoV2 viral protease via in silico approach. The compounds were selected on the basis of their molecular docking values and they were subjected to molecular dynamics simulations about 50 ns to determine the stability and the thermodynamic feasibility between the target and the ligands. Binding energies like hydrogen bonding, hydrophobic and electrostatic interactions of the complexes were determined after MD simulations. The Pharmacokinetics and drug likeness evaluation of the compounds provide a strong evidence for the use of these compounds in developing drugs for clinical trials. Thus, the current study reveals the potential phytoconstituents present in Tectona grandis Linn to inhibit COVID-19 viral protease and thereby act as a lead therapeutic agent.Communicated by Ramaswamy H. Sarma.

Identification of sustainable trypsin active-site inhibitors from Nigrospora sphaerica strain AVA-1.

Trypsin is a protein-digesting enzyme that is essential for the growth and regeneration of bone, muscle, cartilage, skin, and blood. The trypsin inhibitors have various role in diseases such as inflammation, Alzheimer's disease, pancreatitis, rheumatoid arthritis, cancer prognosis, metastasis and so forth. From 10 endophytic fungi isolated, we were able to screen only one strain with the required activity. The fungus with activity was obtained as an endophyte from Dendrophthoe falcata and was later identified as Nigrospora sphaerica. The activity was checked by enzyme assays using trypsin. The fungus was fermented and the metabolites were extracted and further purified by bioassay-guided chromatographic methods and the compound isolated was identified using gas chromatography-mass spectrometry. The compound was identified as quercetin. Docking studies were employed to study the interaction. The absorption, distribution, metabolism, and excretion analysis showed satisfactory results and the compound has no AMES and hepatotoxicity. This study reveals the ability of N. sphaerica to produce bioactive compound quercetin has been identified as a potential candidate for trypsin inhibition. The present communication describes the first report claiming that N. sphaerica strain AVA-1 can produce quercetin and it can be considered as a sustainable source of trypsin active-site inhibitors.

Copolymerization of Styrene and Pentadecylphenylmethacrylate (PDPMA): Synthesis, Characterization, Thermomechanical and Adhesion Properties.

The copolymerization of styrene (St) with a bioderived monomer, pentadecylphenyl methacrylate (PDPMA), via atom transfer radical polymerization (ATRP) was studied in this work. The copolymerization reactivity ratio was calculated using the composition data obtained from 1H NMR spectroscopy, applying Kelen-Tudos and Finemann-Ross methods. The reactivity ratio of styrene (r1 = 0.93) and PDPMA (r2 = 0.05) suggested random copolymerization of the two monomers with alternation. The copolymerization conversion increased with increasing PDPMA concentration of the feed, upto 70 wt % PDPMA, but decreased thereafter. The molecular weight determined by gel permeation chromatography was lower than the theoretical values and the polydispersity increased from 1.32 to 2.19, with increasing PDPMA content in the feed. The influence of styrene content on the glass transition and thermal decomposition behavior of the copolymers was studied by differential scanning calorimetry (DSC) and thermogravimetric analysis, respectively. Morphological characterization by transmission electron microscopy (TEM) revealed a phase separated soft core-hard shell type structure. The complex viscosity and adhesion properties like peel strength and lap shear strength of the copolymer on different substrates increased with increasing styrene content.