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Effective management of excessive bleeding requires liquid hemostatic agents, especially in scenarios involving uncompressible and postoperative hemorrhage. This study introduces the microbial exopolysaccharide floccuronic acid (FA) as a liquid hemostatic agent, characterized by a high weight average molecular weight of 2.38 × 108 Da. The investigation focuses on the flocculation effect, hemostatic efficiency in both in vitro and in vivo settings, elucidating its hemostatic mechanism, and assessing its safety profile. Results reveal that FA solution significantly accelerates the coagulation process, leading to the formation of compact clots while specifically interfering with fibrin. Notably, FA demonstrates excellent hemostatic effects in animal liver models and a rat arterial rebleeding model. The biocompatible and biodegradable characteristics further underscore FA's potential as a valuable liquid hemostatic material, particularly suited for non-compressible and re-bleeding scenarios. [ABSTRACT FROM AUTHOR]

Bioflocculants like polysaccharides are excellent alternatives to harmful synthetic flocculants and usability under stricter levels of ecosystem protection. In this study, an exopolysaccharide producing strain Paenibacillus sp. M21629 was isolated. The exopolysaccharide was abundant in carboxylic groups and named floccuronic acid with a high weight average molecular weight of 2.38 × 108 Da. The hexasaccharide repeating units of floccuronic acid were →3)-α-D-Man p -(1 → 3)-4-Suc-β-D-Man p -(1 → 3)-β-D-Glc p -(1 → 4)-β-D-Glc p A-(1 → 4)[4,6-Pyr-β-D-Gal p -(1 → 3)]-β-D-Gal p -(1→. The floccuronic acid at 0.5–1 ppm showed high turbidity removal efficiency in kaolin suspension (99.8%), coal wastewater (98.8%), and high-turbidity drinking water (89.2%). The flocculation ability of floccuronic acid depended on the instability of solid particles. Owing to these encouraging results, floccuronic acid is expected to be a useful bioflocculant applied in wastewater treatment and the utilization of water resources. [Display omitted] • A Paenibacillus isolate produces the exopolysaccharide floccuronic acid with molecular weight of 2.38×108 Da. • The floccuronic acid is composed of mannose, galactose, glucose, and gluconic acid with pyruvic and succinyl substitutions. • The floccuronic acid shows high turbidity removal efficiency in several suspensions. • The bridging mechanism underpins the flocculant action of floccuronic acid. [ABSTRACT FROM AUTHOR]

• Salecan mitigates LPS-induced ALI by preserving alveolar structure, reducing edema, and suppressing inflammation. • Salecan modulates oxidative stress pathways, reversing ALI-associated metabolic alterations. • Salecan may inhibit LPS-induced ALI through Keap1-Nrf2/HO-1 pathway. • Salecan interacts with macrophages, alleviating LPS-triggered apoptosis and inflammation. Acute lung injury (ALI) is a severe clinical condition with high mortality, characterized by rapid onset and limited treatment options. The pathogenesis of ALI involves inflammation and oxidative stress. The polysaccharide salecan, a water-soluble β-(1,3)-D-glucan, has been found to possess numerous pharmaceutical effects, including anti-inflammatory properties, inhibition of oxidative stress, and anti-fatigue effects. This study aims to investigate the protective effect and underlying mechanism of salecan against LPS-induced ALI in mice. Using an in vivo LPS-induced ALI mouse model and an in vitro RAW264.7 cell system, we investigated the role of salecan in ALI with various experimental approaches, including histological staining, quantitative real-time PCR, flow cytometry, western blot analysis, and other relevant assays. Pre-treatment with salecan effectively attenuated LPS-induced ALI in vivo, reducing the severity of pulmonary edema, inflammation, and oxidative stress. NMR-based metabolomic profiling analysis revealed that salecan attenuated LPS-induced metabolic imbalances associated with ALI. Furthermore, salecan downregulated Keap1 and upregulated Nrf2 and HO-1 protein levels, indicating its modulation of the Keap1-Nrf2/HO-1 signaling pathway as a potential mechanism underlying its protective effects against ALI. In vitro studies on RAW264.7 cells revealed that salecan exhibited binding affinity towards macrophages, thereby alleviating LPS-induced apoptosis and inflammation, which underpin its therapeutic potential against ALI. Our study suggests that salecan can alleviate LPS-induced ALI by modulating oxidative stress, inflammatory response, and apoptosis through the activation of the Keap1-Nrf2/HO-1 pathway. These findings provide novel insights into the potential therapeutic use of salecan for the treatment of ALI. [ABSTRACT FROM AUTHOR]