Design, synthesis, and bioactivity evaluation of PABA-based five- and six-membered heterocyclic Schiff base quaternary ammonium chitosan derivatives.

This study reports the green and efficient synthesis of two novel categories of quaternary ammonium chitosan derivatives via ion-exchange, aiming to enhance their biological activities and expand potential applications. Para-aminobenzoic acid (PABA) was reacted with five- and six-membered heteroaromatic aldehydes to form Schiff bases, which were ionized and introduced into two types of quaternary ammonium chitosan: N-(2-hydroxypropyl) trimethylammonium chloride chitosan (HACC) and N, N, N-trimethyl chitosan iodide (TMCI). by replacing chloride and iodide ions.

Innovative pH-responsive chitosan hydrogel: A systematic study on VB12 controlled release and multifunctional biological effects via synergistic grafting of cysteine and arginine.

In this study, a chitosan-based hydrogel (CDA) was developed by crosslinking with difunctional aldehyde polyethylene glycol (DFPEG) and functionalizing with cysteine and arginine, aiming to construct a pH-responsive delivery system for Vitamin B12 (VB12). The modifications significantly enhanced the water solubility, antibacterial activity, and bioactivity of chitosan, while DFPEG crosslinking formed a stable three-dimensional network, enabling excellent pH sensitivity and sustained release capability. Structural and physicochemical characterization via H NMR, FTIR, XRD, TGA, SEM, and rheological analysis confirmed the hydrogel's uniform network, superior mechanical strength, and favorable flow adaptability.

Synthesis and performance optimization of dual-modified chitosan Derivatives: Effects of novel zwitterionic and quaternary ammonium groups on antibacterial, antioxidant, and biocompatibility properties.

In this study, a series of halogenated zwitterionic-quaternary ammonium chitosan derivatives were synthesized through a dual-modification strategy. Their structures were confirmed by Fourier-transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (H NMR), thermogravimetric analysis (TGA), and X-ray diffraction (XRD) analyses. Antibacterial assays demonstrated that these derivatives possess broad-spectrum activity against Escherichia coli and Staphylococcus aureus, with favorable MIC, MBC, and inhibition rate values.

Prodigiosin pigment-producing Streptomyces diastaticus on Semi-solid media and anticancer activity against colorectal (COLO-205) cell line.

The present study insights into the copious application of Prodigiosin as a bio-colorant produced by Actinomycetes using semisolid low-cost substrate media. Reddish pink pigment-producing Actinomycetes were isolated from the rhizosphere soil of the peanut plant and characterized by morphological, biochemical, and molecular analysis. Molecular analysis unveiled that the pigment-producing isolate was identified as Streptomyces diastaticus.

Design and synthesis of novel zwitterionic-quaternary ammonium chitosan derivatives of distinct categories: Strategies for enhancing antibacterial, antioxidant, and biocompatible properties.

To enhance the bioactivity of chitosan and broaden its application scope, two distinct types of zwitterionic-quaternary ammonium derivatives and four specific configurations of dual-modified zwitterionic and quaternary ammonium chitosan derivatives were synthesized. The resulting products were structurally characterized using Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (H NMR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). Their antibacterial, antioxidant properties, and biocompatibility were also evaluated.

On-demand dual-stimuli-responsive hydrogels for localized and sustained delivery of MP-L [I5R8] to treat bacterial wound infections.

This study presents the development of two novel injectable dual-responsive polyanionic hydrogels (DRPHs) based on N-isopropylacrylamide (NIPAM), incorporating carboxylic acid comonomers for temperature- and pH-responsive drug release. These hydrogels were designed for the sustained and localized delivery of the antimicrobial peptide MP-L [I5R8], targeting multidrug-resistant bacteria (MDRB) in wound infections. The physicochemical characterization confirmed polymer formation and comonomer integration through Fourier-transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR).

Regulatory effects of different spacer alkyl chains on the in vitro antioxidant and antibacterial activities of chitosan quaternary ammonium/phosphonium salt derivatives.

In this study, three chitosan quaternary phosphonium salts and three chitosan quaternary ammonium salts with varying spacer chain lengths were synthesized. Structure characterization of the obtained products was conducted using Fourier-transform infrared spectroscopy, nuclear magnetic resonance, thermogravimetric analysis, and elemental analysis. Additionally, the in vitro scavenging efficiency of these derivatives against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and superoxide radicals, as well as their antibacterial activities against Escherichia coli (E.

Synthesis, crystal structure, characterization and antimicrobial activities of ternary chiral mononuclear Schiff base copper(II) complexes.

[CuL(tmen)] is a sequence of four ternary mononuclear Schiff base copper(II) complexes that are derived from L-valine, suitable 5'-substituted-2'-hydroxyacetophenones (where the substituents are -Cl for L, -Me for L, -OMe for L, and -H for L), and tmen (where tmen-N,N,N',N' tetramethyl ethylenediamine). Without isolating the Schiff base ligand or producing any other intermediate products, all of the complexes were synthesised. These compounds were identified using elemental analysis, molar conductance, UV-Vis, FTIR, EPR, VSM-RT, and CD spectra.

Hydrogel-antimicrobial peptide association: A novel and promising strategy to combat resistant infections.

Infections from multi-drug resistant bacteria (MDRB) have raised a worldwide concern, with projections indicating that fatalities from these infections could surpass those from cancer by 2050. This troubling trend is influenced by several factors, including the scarcity of new antibiotics to tackle challenging infections, the prohibitive costs of last-resort antibiotics, the inappropriate use of antimicrobial agents in agriculture and aquaculture, and the over-prescription of antibiotics in community settings. One promising alternative treatment is the application of antimicrobial peptides (AMPs) against MDRB.

Shark chondroitin sulfate gold nanoparticles: A biocompatible apoptotic agent for osteosarcoma.

Osteosarcoma is a highly aggressive tumor that originates in the bone and often infiltrates nearby bone cells. It is the most prevalent type of primary bone cancer among the various bone malignancies. Traditional cancer treatment methods such as surgery, chemotherapy, immunotherapy, and radiotherapy have had restricted success.

Comprehensive study of Biginelli's compounds show antibacterial activity against Vibrio parahaemolyticus of two strains: In vitro and computational approaches.

This study addresses the critical challenges faced by global aquatic industries such as overfishing, habitat destruction, pollution, climate change, and unsustainable aquaculture practices. It focuses on developing effective solutions by synthesizing potent inhibitors against Vibrio parahaemolyticus of two strains namely: MTCC-451 (A) and Vp-S14 (B). Biginelli's compounds (B1-4) were identified as promising inhibitors with confirmed antibacterial activity through in silico and in vitro studies.

Novel ionic chitosan derivatives based on pyridinium sulfonate: Synthesis, characterization, and studies on antimicrobial, antioxidant, and biocompatibility properties.

To improve the solubility, antimicrobial efficacy, antioxidant capacity, and biocompatibility of chitosan for broader applications, a series of novel ionic chitosan derivatives were synthesized in this study by amidating chitosan with carboxyl pyridinium sulfonate. These derivatives were characterized through various analytical techniques, including FTIR, H NMR, UV, TGA, and XRD. Proton NMR was particularly utilized to determine the degree of substitution.

Efficacy of chondroitin sulfate as an emerging biomaterial for cancer-targeted drug delivery: A short review.

The global increase in cancer incidence over the past decade highlights the urgent need for more effective therapeutic strategies. Conventional cancer treatments face challenges such as drug resistance and off-target toxicity, which affect healthy tissues. Chondroitin sulfate (CHDS), a naturally occurring bioactive macromolecule, has gained attention because of its biocompatibility, biodegradability, and low toxicity, positioning it as an ideal candidate for cancer-targeted drug delivery systems.

Advances in bioinspired nanomaterials managing microbial biofilms and virulence: A critical analysis.

Microbial virulence and biofilm formation stand as a big concern against the goal of achieving a green and sustainable future. Microbial pathogenesis is the process by which the microbes (bacterial, fungal, and viral) cause illness in their respective host organism. 'Nanotechnology' is a state-of-art discipline to address this problem.

Nanomaterial in controlling biofilms and virulence of microbial pathogens.

The escalating threat of antimicrobial resistance (AMR) poses a grave concern to global public health, exacerbated by the alarming shortage of effective antibiotics in the pipeline. Biofilms, intricate populations of bacteria encased in self-produced matrices, pose a significant challenge to treatment, as they enhance resistance to antibiotics and contribute to the persistence of organisms. Amid these challenges, nanotechnology emerges as a promising domain in the fight against biofilms.

Biomedical and ecosafety assessment of marine fish collagen capped silver nanoparticles.

In the rapidly evolving landscape of silver nanoparticles (Ag NPs) synthesis, the focus has predominantly been on plant-derived sources, leaving the realm of biological or animal origins relatively uncharted. Breaking new ground, our study introduces a pioneering approach: the creation of Ag NPs using marine fish collagen, termed ClAg NPs, and offers a comprehensive exploration of their diverse attributes. To begin, we meticulously characterized ClAg NPs, revealing their spherical morphology, strong crystalline structure, and average diameter of 5 to 100 nm.

Evaluation of heavy metal removal and antibiofilm efficiency of biologically synthesized chitosan- silver Nano-bio composite by a soil actinobacterium Glutamicibacter uratoxydans VRAK 24.

Biological synthesis of nanoparticles is cost-effective as well as safer than physical and chemical methods. This study focuses on the biological synthesis of silver nanoparticles using Glutamicibacter uratoxydans which remains still unexplored. The synthesized silver nanoparticles are encapsulated with chitosan to prepare nanobiocomposite.

Synthesis and in vitro characteristics of biogenic-derived hydroxyapatite for bone remodeling applications.

The inorganic component of bone matrix, hydroxyapatite (HAp) (with formula Ca(PO)(OH)), can be obtained from inexpensive waste resources that serve as excellent calcium precursors. In the present study, HAp nano-powder was synthesized from eggshells (ES) and crab shells (CS) by wet chemical precipitation method. Also, a hybrid sample was considered which is a mixture of HAp nano-powder synthesized from eggshells (25%) and crab shells (75%) (EC).

Bacterial Polyhydroxyalkanoates-based Therapeutics-delivery Nano-systems.

Microbial polyhydroxyalkanoates (PHAs) are bio-based aliphatic biopolyester produced by bacteria as an intracellular storage material of carbon and energy under stressed conditions. PHAs have been paid attention to due to their unique and impressive biological properties including high biodegradability, biocompatibility, low cytotoxicity, and different mechanical properties. Under this context, the development of drug-delivery nanosystems based on PHAs has been revealed to have numerous advantages compared with synthetic polymers that included biocompatibility, biodegradability, non-toxic, and low-cost production, among others.

Biocompatible polysaccharide fabricated graphene oxide nanoparticles: A versatile nanodrug carrier to deliver κ- carrageenan against cancer cells.

A graphene oxide mediated hybrid nano system for pH stimuli-responsive and in vitro drug delivery targeted for cancer was described in this study. Graphene oxide (GO) functionalized Chitosan (CS) mediated nanocarrier capped with xyloglucan (XG) was fabricated with and without Kappa carrageenan (κ-C) from red seaweed, Kappaphycus alverzii, as an active drug. FTIR, EDAX, XPS, XRD, SEM and HR-TEM studies were carried out for GO-CS-XG nanocarrier loaded with and without active drugs to understand the physicochemical properties.

Effect of a polyherbal formulation on L-thyroxine induced hyperthyroidism in a rat model: In vitro and in vivo analysis and identification of bioactive phytochemicals.

An excess of thyroid hormones in the blood characterizes hyperthyroidism. Long-term use of prescription medications to treat hyperthyroidism has substantial adverse effects and when discontinued, the symptoms frequently recur. Several plant species have been utilized to cure hyperthyroidism.

Rational Design of Hydrogels for Cationic Antimicrobial Peptide Delivery: A Molecular Modeling Approach.

In light of the growing bacterial resistance to antibiotics and in the absence of the development of new antimicrobial agents, numerous antimicrobial delivery systems over the past decades have been developed with the aim to provide new alternatives to the antimicrobial treatment of infections. However, there are few studies that focus on the development of a rational design that is accurate based on a set of theoretical-computational methods that permit the prediction and the understanding of hydrogels regarding their interaction with cationic antimicrobial peptides (cAMPs) as potential sustained and localized delivery nanoplatforms of cAMP. To this aim, we employed docking and Molecular Dynamics simulations (MDs) that allowed us to propose a rational selection of hydrogel candidates based on the propensity to form intermolecular interactions with two types of cAMPs (MP-L and NCP-3a).