Dextran '70' 6% / Sodium chloride 0.9% infusion 500ml bags

Global concerns about environmental pollution, poor waste management, and the rise in antimicrobial resistance due to uncontrolled antibiotic use have driven researchers to seek alternative, multifaceted solutions. Plants, animals, microorganisms, and their processing wastes serve as valuable sources of natural biopolymers and bioactive compounds. Through nanotechnology, these can be assembled into formulations with enhanced antimicrobial properties, high safety, and low toxicity. This review explores polysaccharides, including chitosan, alginate, starch, pectin, cellulose, hemicellulose, gums, carrageenan, dextran, pullulan, and hyaluronic acid, used in nanotechnology, highlighting their advantages and limitations as nanocarriers. Addressing the global urgency for alternative antimicrobials, we examined natural compounds derived from plants, microorganisms, and animals, such as phytochemicals, bacteriocins, animal antimicrobial peptides, and proteins. Focusing on their protection and retained activity, this review discusses polysaccharide-based nanoformulations with natural antimicrobials, including nanoparticles, nanoemulsions, nanocapsules, nanoplexes, and nanogels. Special emphasis is placed on strategies and formulations for the encapsulation, entrapment, and conjugation of natural compounds using polysaccharides as protective carriers and delivery systems, including a brief discussion on their future applications, prospects, and challenges in scaling up.

Abstract licence: CC BY

Thin film hydration methods are widely used to assemble giant unilamellar vesicles (GUVs), but their efficiency drops sharply in solutions of physiological ionic strength due to enhanced adhesion between stacked lipid bilayers, which suppresses bud and foam-like mesophase formation. Here, polymer-coated nanocellulose paper (PCP) is introduced as a nanostructured substrate that overcomes this limitation. Hydration of lipid films on PCP, termed PCP-assisted hydration, achieves high GUV yields across a broad temperature range (4 °C-45 °C) using diverse soluble polymers, including ultralow-gelling agarose, hyaluronic acid, dextran, carrageenan, and polylysine. The nanoscale curvature of the cellulose fibers and the osmotic pressure generated by polymer dissolution act synergistically to promote membrane budding even under physiological salt conditions. The approach is scalable-supporting GUV production from millimeter-sized pieces to large-format sheets-and biocompatible, enabling encapsulation of complex biochemical systems such as cell-free expression mixtures and actin-fascin assemblies. PCP-assisted hydration thus provides a robust, versatile, and high-yielding platform for generating functional GUVs under physiological conditions.

Abstract licence: CC BY

Active endolysosomal pH regulation is essential for optimal enzymatic activity. To measure acidification, pH sensors can be delivered to acidic compartments using labeled dextran polymers or proteins. However, commercial probes have limited sensitivity in the acidic endolysosomal range or their fluorescence undergoes degradation. Herein, we introduce the new pH-sensitive probe ApHID, a green-emitting sensor with optimal dynamic range matching the acidity of endosomes and lysosomes. Acid pH indicator dye (ApHID) has a pKa near 5, increasing brightness with acidity, and withstands oxidation and photobleaching. We used ApHID dextrans to measure endolysosomal pH in macrophages and compared it to other commercially available sensors. ApHID reported pH accurately and stably over time in cell culture and was sensitive to subtle variations in organelle acidification in real time. Overall, ApHID circumvents limitations of currently available commercial probes and can provide utility in demanding applications such as intravital imaging of tissues.

Abstract licence: CC BY

Neurodegenerative diseases, which pose significant challenges for effective treatment, often involve risk variants of lysosomal gene products that disrupt lysosomal function, leading to the accumulation of indigestible materials and damage to brain cells. The lysosome is a degradative organelle and a signaling hub that senses nutrient availability. How lysosomal dysfunction contributes to neurodegenerative diseases is an important open question. In this study, we identified CLN3 (ceroid lipofuscinosis, neuronal 3), an endolysosomal protein that is linked to Batten disease, as an evolutionarily conserved protein that facilitates lysosomal chloride efflux. Additionally, we report that a natural compound with anti-inflammatory properties-the curcumin analog C1, which is a TFEB (transcription factor EB) activator-could enhance CLN3 activity and improve lysosomal function. These findings provide new insight into the role of CLN3 in lysosomal ion homeostasis and raise the possibility that modulation of the TFEB-CLN3 signaling axis may hold therapeutic potential for lysosomal storage disorders.

Abstract licence: CC BY