Skin wounds occur frequently in everyday life, and severe wounds can be life-threatening. Portulaca oleracea L. is a medicinal plant widely used in moisturisers and other skincare products, and polysaccharides are considered its principal active constituents. However, research on the wound-healing effects of P. oleracea polysaccharides and their underlying molecular mechanisms remains limited. In this study, a novel polysaccharide designated WPOP-1-1 was isolated from P. oleracea L., and characterised. The weight-average molecular weight (Mw) of WPOP-1-1 was 7.4 kDa. The backbone of WPOP-1-1 is mainly composed of 1,4-linked glucopyranose (Glcp) and 1,4-linked galactopyranose (Galp) repeating units, with 1,5-linked arabinofuranose (Araf) or terminal glucopyranose (t-Glcp) branches attached at O-6 of the glucopyranose units. Combined in vitro and in vivo assays verified that WPOP-1-1 boosted keratinocyte and fibroblast migration, accelerated mouse wound closure, restored epidermal barrier and alleviated inflammatory infiltration. Proteomic enrichment, immunofluorescence, and western blot results collectively suggested that WPOP-1-1 may upregulate proteins of the Notch pathway. Collectively, these findings indicate that WPOP‑1‑1 may contribute to wound healing by modulating Notch signaling, providing preliminary evidence for its potential use in wound repair and skincare products.
Microbial exopolysaccharides (EPS) are promising sustainable carbohydrate polymers for aqueous biomaterial and skincare-related formulations; however, achieving high production efficiency together with favorable physicochemical and functional properties remains challenging. In this study, an EPS-producing Bacillus licheniformis strain, CPS3, was isolated from peony flowers and improved by N-methyl-N′-nitro-N-nitrosoguanidine mutagenesis to obtain the high-yield mutant CPS3–3. Subsequent sucrose-centered medium optimization using response surface methodology increased EPS production to 34.2 g/L. The purified EPS produced under optimized sucrose-rich conditions was predominantly composed of fructose (96.55%) with minor glucose (3.45%), suggesting a fructose-rich levan-type polysaccharide. Gel permeation chromatography revealed a low weight-average molecular weight of 7.82 kDa and a narrow molecular weight distribution. FT-IR, ¹H NMR, and XRD analyses further supported its polysaccharide characteristics and predominantly amorphous structure. The EPS showed excellent water solubility, moderate viscosity, water absorption capacity, and favorable long-term water-retention ability, indicating good compatibility with aqueous formulation systems. In UVB-damaged HaCaT keratinocytes, EPS treatment improved cell viability to approximately 70%, reduced intracellular ROS levels from approximately 550% to 380% at 200 μg/mL, and restored epidermal barrier-related gene expression, including FLG, CASP14, and LOR. These findings demonstrate that CPS3–3-derived low-molecular-weight levan-type EPS is a promising microbial carbohydrate polymer for hydration-related and UVB-protective formulation applications.
Despite advances in wound care, developing multifunctional biomimetic dressings that promote tissue regeneration while controlling bacterial infection remains challenging. Biomimetic scaffolds that combine structural support, bioactive cues, and antibacterial properties have emerged as promising candidates for addressing this need. In this study, bacterial cellulose (BC), a carbohydrate-based polymer with a hydrated nanofibrous architecture, was biosynthesized and characterized before integration into the bilayer scaffold. To enhance the biological functionality of the scaffold, decellularized small intestinal submucosa (SIS) was blended with polyvinyl alcohol (PVA) to improve fiber formation and mechanical properties, and with ciprofloxacin (Cip) to impart antibacterial activity, followed by electrospinning into composite nanofibers. Herein, a functionally compartmentalized bilayer wound dressing was designed by integrating a bacterial cellulose layer with SIS/PVA/Cip electrospun nanofibers for complementary structural, regenerative, and antibacterial functions within a single construct. Comparative characterization revealed differences in swelling, wettability, mechanical properties, and degradation among the tested groups, while the bilayer scaffold exhibited sustained ciprofloxacin release. In vitro studies confirmed strong antibacterial activity and excellent cytocompatibility. Furthermore, in vivo experiments revealed accelerated re-epithelialization and increased collagen deposition relative to both negative and positive control groups. Collectively, these findings highlight the potential of bacterial cellulose-based bilayer scaffold for multifunctional wound-dressing applications.
Hypoxia impairs infected diabetic wound healing by suppressing angiogenesis, sustaining inflammation, and delaying tissue repair. We developed CSZM, a self-moisturizing, adhesive, and injectable calcium-crosslinked sodium alginate hydrogel containing ZnO2 and MnO2 nanoparticles. In acidic wound microenvironments, ZnO2 releases antibacterial Zn2+ and H2O2, whereas MnO2 converts H2O2 into O2 and limits peroxide accumulation. At pH 5.5, dissolved O₂ remained at 1.302 ± 0.027 mg/L after 48 h. Released Zn2+ coordinated with alginate carboxylate groups, increasing crosslinking density, restricting excessive swelling, and enhancing water retention. CSZM exhibited a porous structure, shear-thinning and self-healing behavior, a storage modulus of approximately 507.5 Pa at 10 rad s−1, and 93.1% modulus recovery after three alternating-strain cycles. In vitro, CSZM protected HUVECs from hypoxic injury, enhanced migration and VEGF- and CD31-associated angiogenic responses, favored a CD206-associated pro-reparative macrophage phenotype, and inhibited planktonic bacteria and biofilms, achieving antibacterial efficiencies of 78% against S. aureus and over 83% against Escherichia coli. In infected diabetic wounds, CSZM reduced bacterial burden and inflammation, increased angiogenesis-associated marker expression and collagen deposition, and achieved 98.3 ± 0.5% wound closure by day 14 with favorable biocompatibility. This study provides a promising multifunctional oxygen-generating hydrogel platform for the treatment of infected diabetic wounds.
