Metal complexes activated by light can combat infections by triggering the photodynamic inactivation of bacteria. Herein, we report six mixed-ligand nickel(II) complexes with the formulation [Ni(NN)(L)] (1-6), where NN represents an N,N-donor phenanthroline ligand, specifically 1,10-phenanthroline (phen in 1, 2), dipyrido[3,2-d:2',3'-f]quinoxaline (dpq in 3, 4), and dipyrido[3,2-a:2',3'-c]phenazine (dppz in 5, 6), while L is an O,O donor bidentate ligand derived from catechol (cat, in 1, 3, 5) or esculetin (esc, in 2, 4, 6). The paramagnetic d octahedral complexes demonstrated good dark and photostability in the solution phase and exhibited significant light absorption in the visible (400-700 nm) region.
View Article and Find Full Text PDFThree novel polypyridyl-Co(III)-vitamin B complexes viz., [Co(CF-phtpy)(SBVB)]Cl (Co1), [Co(anthracene-tpy)(SBVB)]Cl (Co2), [Co(NMe-phtpy)(SBVB)]Cl (Co3), where 4'-(4-(trifluoromethyl)phenyl)-2,2':6',2''-terpyridine=CF-phtpy, 4'-(anthracen-9-yl)-2,2':6',2''-terpyridine=anthracene-tpy;, 4-([2,2':6',2''-terpyridin]-4'-yl)-N,N-dimethylaniline=NMe-phtpy, (E)-5-(hydroxymethyl)-4-(((2-hydroxyphenyl)imino)methyl)-2-methylpyridin-3-ol=HSBVB were successfully developed for aPDT (antibacterial photodynamic therapy) applications. Co1-Co3 exhibited an intense absorption band at ca.
View Article and Find Full Text PDFDiamond-type silicon has a work function of ≈4.8 eV, and conventional n- or p-type doping modifies the value only between 4.6 and 5.
View Article and Find Full Text PDFGeneration of voluminous single-use plastic waste and byproducts from agricultural harvests such as rice straws (RSs) are major global challenges due to their disposal issues, contributing to greenhouse gas emissions, and affecting the ecological system with threats to human health. A scalable, low-cost, and eco-friendly strategy for fabricating cellulose-silica-based drinking straws, free from microplastics and adhesive, through strategic valorization of RS is reported. Functionalization by delignification--crosslinking of RS leads to development of straws with high water stability (∼5 days), solvothermal stability (0°C-95°C), tensile strength (128 MPa), low migration values (<60 mg/kg), improved biodegradability (∼126 days) with reduced wettability and hydrophobicity.
View Article and Find Full Text PDFRice husk (RH) is a common agricultural waste generated during the rice milling process; however, a major portion is either burned or disposed of in landfills, posing significant environmental risks. In this study, RH waste was transformed into bio-based catalysts delignification cum growth of MoS (DRH-MoS) for efficient pollutant dye removal and microbial decontamination. The developed DRH-MoS exhibits nanoflower-like structures with a 2H-MoS phase and a narrow band gap of 1.
View Article and Find Full Text PDFIn the present work, phosphorylated cellulose (PC) gel has been produced following an environmentally benign approach using agro-based chemicals with improved yield. The PC gels produced were transparent, negatively charged with high consistency, charge content (1133.33 mmol/kg), degree of substitution (DS) of 0.
View Article and Find Full Text PDFIn this study, sugarcane bagasse (SB) was strategically subjected to a delignification process followed by the in situ growth of multi-layered molybdenum disulfide (MoS) nanosheets with hexagonal phase (2H-phase) crystal structure via hydrothermal treatment. The MoS nanosheets underwent self-assembly to form nanoflower-like structures in the aligned cellulose inter-channels of delignified sugarcane bagasse (DSB), the mechanism of which was understood through FTIR and XPS spectroscopic studies. DSB, due to its porous morphology and abundant hydroxyl groups, shows remediation capabilities of methylene blue (MB) dye through physio-sorption but shows a low adsorption capacity of 80.
View Article and Find Full Text PDFBackground: Pulmonary tuberculosis has emerged as one of the leading causes of deaths across the globe. The prevalence of Mycobacterium tuberculosis has also shown an increasing trend over the time which may be attributed to the increase in multidrug resistant strains and HIV epidemics. There are several factors like change in the gene structure and cellular activities of the host and the bacterium which may have changed the host response towards tuberculosis.
View Article and Find Full Text PDFThe glycoside hydrolase family 39 (GH39) proteins are renowned for their extremophilic and multifunctional enzymatic properties, yet the molecular mechanisms underpinning these unique characteristics continue to be an active subject of research. In this study, we introduce WsuXyn, a GH39 protein with a molecular weight of 58 kDa, originating from the thermophilic Geobacillus sp. WSUCF1.
View Article and Find Full Text PDFHerein, five novel polypyridyl-based Co(III) complexes of Schiff bases, , [Co(dpa)(L)]Cl (1), [Co(dpa)(L)]Cl (2), [Co(L)(L)]Cl (3), [Co(L)(L)]Cl (4), and [Co(L)(L)]Cl (5), where dpa (dipicolylamine) = bis(2-pyridylmethyl)amine; HL = ()-2-((2-hydroxybenzylidene)amino)phenol; HL = ()-5-(hydroxymethyl)-4-(((2-hydroxyphenyl)imino)methyl)-2-methylpyridin-3-ol; L = 4'-phenyl-2,2':6',2''-terpyridine (ph-tpy); and L = 4'-ferrocenyl-2,2':6',2''-terpyridine (Fc-tpy), were synthesized and characterized. Complexes 1, 3, and 4 were structurally characterized by single-crystal XRD, indicating an octahedral CoNO coordination core. The absorption bands of these complexes were observed in the visible range with a at ∼430-485 nm.
View Article and Find Full Text PDFThe increase in antibacterial drug resistance is threatening global health conditions. Recently, antibacterial photodynamic therapy (aPDT) has emerged as an effective antibacterial treatment with high cure gain. In this work, three Zn(II) complexes viz.
View Article and Find Full Text PDFSoy protein isolate (SPI) has received widespread attention of the biomedical research community primarily due to its good biocompatibility, biodegradability, high availability and low cost. Herein, glutaraldehyde cross-linked microporous sponge-like SPI scaffolds were prepared using the cryogelation technique for tissue engineering applications. The prepared SPI scaffolds possess an interconnected porous structure with approximately 90% porosity and an average pore size in the range of 45-92 μm.
View Article and Find Full Text PDFTypically, transition metals are considered as the centers for the activation of dinitrogen. Here we demonstrate that the nitride hydride compound Ca CrN H, with robust ammonia synthesis activity, can activate dinitrogen through active sites where calcium provides the primary coordination environment. DFT calculations also reveal that an associative mechanism is favorable, distinct from the dissociative mechanism found in traditional Ru or Fe catalysts.
View Article and Find Full Text PDFFour new Co complexes, [Co(bpy) (acac)]Cl (1), [Co(phen) (acac)]Cl (2), [Co(bpy) (cur)]Cl (3), [Co(phen) (cur)]Cl (4), where bpy=2,2'-bipyridine (1 and 3), phen=1,10-phenanthroline (2 and 4), acac=acetylacetonate (1 and 2), cur=curcumin monoanion (3 and 4) have been designed, synthesized and fully characterized. The X-ray crystal structures of 1 and 2 indicated that the CoN O core has a distorted octahedral geometry. The photoactivity of these complexes was tuned by varying the π conjugation in the ligands.
View Article and Find Full Text PDFMonitoring of food products by government agencies for their compliance to regulatory limits is an essential step in controlling foodborne outbreaks. For monitoring purposes, an extensive setup of the surveillance system is used, which involves ISO 17025:2017 accredited laboratories for food testing. Participation in proficiency testing (PT) programs is a requirement of ISO 17025:2017, which ensures data accuracy and analyst competency.
View Article and Find Full Text PDFTopochemical reactions have led to great progress in the discovery of new metastable compounds with novel chemical and physical properties. With these reactions, the overall crystal structure of the host material is generally maintained. Here we report a topochemical synthesis of a hexagonal nitride hydride, h-Ca CrN H, by heating an orthorhombic nitride, o-Ca CrN , under hydrogen at 673 K, accompanied by a rotational structural transformation.
View Article and Find Full Text PDFTransparent wood, a sustainable material, holds the potential to replace conventional petroleum-based polymers because of its renewable and biodegradable properties. It has been recently used for construction, energy storage, flexible electronics, and packaging applications. Life cycle analysis (LCA) of transparent wood would provide the environmental impacts during its production and end-of-life (EOL).
View Article and Find Full Text PDFCellulose is one of the most abundant renewable biopolymer in nature and is present as major constituent in both plant cell walls as well as synthesized by some microorganisms as extracellular products. In both the systems, cellulose self-assembles into a hierarchical ordered architecture to form micro to nano-fibrillated structures, on basis of which it is classified into various forms. Nanocellulose (NCs) exist as rod-shaped highly crystalline cellulose nanocrystals to high aspect ratio cellulose nanofibers, micro-fibrillated cellulose and bacterial cellulose (BC), depending upon the origin, structural and morphological properties.
View Article and Find Full Text PDFEvolving testing methods in food Microbiology have resulted in the need for different types of microbiological reference materials. Based on the research articles available in this area, it is evident that development has been quite substantial in chemical testing compared to Microbiology. The primary reason could be the ease of spiking, and recovery in chemical RM as compared to microbiological RM.
View Article and Find Full Text PDFTuberculosis (TB) is one of the major infectious disease that causes threat to human health and leads to death in most of the cases. Mycobacterium tuberculosis is the causative agent that can affect both pulmonary and extra pulmonary regions of the body. This infection can be presented either as an active or latent form in the patients.
View Article and Find Full Text PDFEmergence of "severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)" causing "COVID-19" or "coronavirus disease 19" as pandemic has got worldwide attention towards hygiene as the first line of defense for the infection control. It is first line of defense not only from COVID-19 but also from other infectious diseases caused by deadly pathogens such as cholera, hepatitis, tuberculosis, polio, etc. Absence of any particular vaccine or treatment let World Health Organization (WHO) recommend to the public to maintain social distancing along with regularly washing their hands with soap, sanitize their hands (where washing is not possible), and disinfect their belongings and buildings to avoid the infection.
View Article and Find Full Text PDFInt J Biol Macromol
September 2019
A highly thermostable laccase from Geobacillus sp. strain WSUCF1 was cloned into Escherichia coli (E. coli) using pRham N-His SUMO expression system.
View Article and Find Full Text PDFCatalytic dehydrogenation of hydrazine was achieved over iminopyridine ligated ruthenium-arene complexes, where the release of H gas, as confirmed by GC-TCD, from hydrazine depends on reaction temperature, base, and solvents. NMR and MS studies indicated an in situ generation of a hydrazine-coordinated ruthenium species, a key intermediate of hydrazine dehydrogenation, via a coordination-assisted activation pathway.
View Article and Find Full Text PDFCore-shell ZIF-8@ZIF-67- and ZIF-67@ZIF-8-based zeolitic imidazolate frameworks (ZIFs) were synthesized solvothermally using a seed-mediated methodology. Transmission electron microscopy-energy-dispersive X-ray spectrometry, line scan, elemental mapping, X-ray photoelectron spectroscopy, and inductively coupled plasma-atomic emission spectroscopy analyses were performed to confirm the formation of a core-shell structure with the controlled Co/Zn elemental composition of ∼0.50 for both the core-shell ZIFs.
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