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Rouse Hardison posted an update 6 months, 1 week ago
High amounts of toxic textile dyes are released into the environment due to coloring and wastewaters treatment processes’ inefficiency. To remove dyes from the environment and wastewaters, researchers focused on applying immobilized enzymes due to mild reaction conditions and enzyme nontoxicity. Laccases are oxidases with wide substrate specificity, capable of degradation of many different dye types. Laccase from Streptomyces cyaneus was expressed on the surface of Saccharomyces cerevisiae EBY100 cells. The specific activity of surface-displayed laccase was increased by toluene-induced lysis to 3.1 U/g of cell walls. For cell wall laccase immobilization within hydrogel beads, alginate was modified by dopamine using periodate oxidation and reductive amination and characterized by UV-Vis, FTIR, and NMR spectroscopy. Cell wall laccase was immobilized within alginate and dopamine-alginate beads additionally cross-linked by oxygen and laccase. The immobilized enzyme’s specific activity was two times higher using dopamine-alginate compared to native alginate beads, and immobilization yield increased 16 times. Cell wall laccase immobilized within dopamine-alginate beads decolorized Amido Black 10B, Reactive Black 5, Evans Blue, and Remazol Brilliant Blue with 100% efficiency and after ten rounds of multiple-use retained decolorization efficiency of 90% with Evans Blue and 61% with Amido Black.Combining biodegradable materials with natural plant components for wound dressing has been receiving significant attention. ART is a sesquiterpene lactone compound extracted from Artemisia annua L., possessing multiple pharmacological effects including antibacterial activity and anti-inflammatory property. Herein, the blended polylactic acid glycolic acid (PLGA)/silk fibroin (SF) membranes loaded with artemisinin (ART) are fabricated through electrospinning. With aid of SF, the fabricated membranes have a good sustained-release effect, and the accumulated ART release can reach 69% after three weeks. PLGA/SF/ART membranes exhibit favorable anti-inflammatory and cell compatibility in vitro evaluations. The in vivo experiment indicates that PLGA/SF/ART2 membranes can shorten the inflammation period and enhance skin regeneration in a full-thickness wound model through down-regulating the expressions of pro-inflammatory cytokines IL-1β and TNF-α. To sum up, the fabricated PLGA/SF/ART2 composite membranes with anti-inflammatory properties can be a proposal wound dressing for chronic wound healing.Most existing hydrogel wound dressings lack gentle detachment property. In this work, novel hydrogels with anti-bacterial and induced detachment properties were prepared. Both gelatin (G) and sodium alginate (SA) are natural polymer materials. The G/SA hydrogels were prepared by dual cross-linking. The addition of SA significantly improves the mechanical properties of composite hydrogels. The tensile modulus and elongation at break of the G/SA hydrogels with 2.0% SA could reach 99.23 ± 2.18 kPa and 85.47 ± 5.01%, respectively. In addition, the interconnected porous network and high swelling ratio (over 9.99 ± 0.33) are beneficial to the transmission of oxygen and absorption of exudates to accelerate the healing of wound. Subsequently, berberine (BBR) was loaded into the G/SA hydrogels. The BBR/G/SA hydrogels show sustained drug release for 168 h and exhibit anti-bacterial effect against Staphylococcus aureus. The results of L929 cells cultured with the hydrogel extracts indicate good biocompatibility. Finally, results of EDTA-induced detachment performances demonstrate that the hydrogels could be removed from the wound as the internal structure destroyed. All illustrated results above demonstrated the BBR carried G/SA hydrogels have potential used as wound dressing materials in future.The heterogeneous structure of lignocellulosic biomass makes it difficult to dissolve its main components (cellulose, hemicelluloses, and lignin) by solvent action with the aim of further applying the mixture of the biological macromolecules generated in the solvent medium. In the present study, the dissolution efficiency (DE) of lignocellulosic sisal fibers in the lithium chloride/dimethylacetamide solvent system (LiCl/DMAc) was evaluated for further application in the formation of hydrogels. MEK inhibitor Catalytic amounts of trifluoroacetic acid (TFA) were used in some experiments, which increased the DE from 40% to 90%. The regeneration of the solutions, either previously filtered or not, led to hydrogels based on sisal lignocellulosic biomass. In brief, the properties of the hydrogels were influenced by the content of the lignocellulosic components in the hydrogels, present both in the dissolved fraction and in the incorporated undissolved fraction (when nonfiltered solutions were used). Hydrogels presented water absorption up to 7479% and resorption content in the lyophilized hydrogel up to 2133%. Extracts obtained from preselected hydrogels exhibited cell viability up to 127% compared to the control group when in contact with fibroblast cultures, exhibiting their noncytotoxic properties. This attribute increased the range of possible applications of these hydrogels, ranging from agriculture to biocompatible materials.Acute or chronic brain injuries promote deaths and the life-long debilitating neurological status where, despite advances in therapeutic strategies, clinical outcome hardly achieves total patient recovery. In recent decades, brain tissue engineering emerged as an encouraging area of research for helping in damaged central nervous system (CNS) recovery. Polysaccharides are abundant naturally occurring biomacromolecules with a great potential enhancement of advanced technologies in brain tissue repair and regeneration (BTRR). Besides carrying rich biological information, polysaccharides can interact and communicate with biomolecules, including glycosaminoglycans present in cell membranes and many signaling moieties, growth factors, chemokines, and axon guidance molecules. This review includes a comprehensive investigation of the current progress on designing and developing polysaccharide-based soft matter biomaterials for BTRR. Although few interesting reviews concerning BTRR have been reported, this is the first report specifically focusing on covering multiple polysaccharides and polysaccharide-based functionalized biomacromolecules in this emerging and intriguing field of multidisciplinary knowledge.