Biopolymers最新文献

Polyhydroxyalkanoates are biodegradable, natural polyesters with the potential to replace petroleum-based plastics. However, high production costs limit their competitiveness. This study assessed the ability of Halomonas boliviensis, a halophilic bacterium, to synthesize polyhydroxybutyrate (PHB) from an agricultural residue, oil palm empty fruit bunch (OPEFB), in highly saline solutions that minimize contamination risk. OPEFB, containing glucose, xylose, and arabinose, offers a cost-effective alternative to pure sugar substrates and aids in waste management. PHB production from OPEFB was compared with fermentations using these sugars. H. boliviensis successfully synthesized PHB from all substrates, achieving the highest PHB content from glucose (54.63%), followed by xylose (40.18%), OPEFB (33.59%), and arabinose (33.52%). Glucose in the OPEFB hydrolysate was entirely depleted after 72 h, while xylose showed minimal consumption. This research highlights the potential of using low-cost carbon sources like OPEFB for PHB production. Future research should focus on optimizing the fermentation process to increase PHB yields, making it a more viable alternative to traditional plastics.

Silicon (Si) is a highly abundant mineral in Earth's crust. It plays a vital role in plant growth, providing mechanical support, enhancing grain yield, facilitating mineral nutrition, and aiding stress response mechanisms. The intricate relationship between silicification and lignin chemistry significantly impacts cell wall structure. Yet, the precise influence of Si on lignin synthesis remains elusive. This study investigated the interaction between Si and lignin model compounds during in vitro synthesis. Employing spectroscopic and microscopic analyses, we delineated how Si concentrations modulate lignin polymerization dynamics, particularly affecting molecular conformation and aggregation behavior over time. Fluctuations in the polymer structure are directly related to both the synthesis time and the concentration of silica. Our results demonstrate that lower Si concentrations promote the aggregation of lignin oligomers into larger particles, while higher concentrations increase the possibility of oligomer repulsion, thus preventing particle growth. These findings elucidate the intricate interplay between Si and lignin, which is crucial for understanding plant cell wall structure and stress resilience. Moreover, the results provide insights for developing lignin-silica materials with increasing applications in industry and medicine.

In this study, scaffolds based on natural polymer gelatin A, blended with polyvinylpyrrolidone were crosslinked by genipin (0.5 and 1 wt%), in order to investigate their mechanical performance and potential for biomedical application. Semi-solid extrusion (SSE) 3D printing technique was used, enabling in situ crosslinking of the blend during processing. Swelling test showed that the swelling ratio reduces with higher concentration of genipin due to an increased crosslinking. The FTIR analysis confirmed the crosslinking of scaffolds by genipin. DSC analysis and mechanical testing have shown improved thermal and mechanical properties. Morphological analysis of scaffolds by FESEM showed increased toughening of the material with the crosslinking. Tensile strength and microhardness showed a significant rise in scaffolds with the increase in genipin content, which was up to 93.8% and 125.3%, respectively. These findings were in accordance with morphological features present in samples. The biological effect of the scaffold matrix system was evaluated by qualitative and quantitative cytotoxicity assessment in vitro, demonstrating the absence of cytotoxicity in tested preparations in a direct test. The cytotoxicity index based on the metabolic activity of cells in an indirect test showed up to 20% reduction of viability compared with the control, confirming the absence of cytotoxicity, which was additionally verified by propidium iodine staining of the cells exposed to scaffolds. The presented gelatin-based crosslinked scaffolds obtained by 3D printing represent good candidates for biomedical application and future research that includes further in vitro and in vivo analysis.

Natural polymers have recently been investigated for various applications, such as 3D printing and healthcare, including treating infections. Among microbial infections, fungal diseases remain overlooked, with limited therapeutic options and high recurrence. Cutaneous cryptococcosis is an opportunistic fungal infection triggered by mechanical inoculation or hematogenous dissemination of the yeast that causes cryptococcal pneumonia and meningitis. Every year, Cryptococcus neoformans endanger the lives of immunosuppressed hosts, resulting in 180,000 deaths per year. Nonetheless, healthy individuals can also be affected by this fungal infection. Cryptococcosis has a restricted and expensive therapeutic regimen with no topical approach to skin manifestations. This study sought to create a 3D printable biodegradable polymeric hydrogel carrying ketoconazole, a low-cost antifungal drug with reported anticryptococcal activity. The developed hydrogel exhibited good 3D printability and rheological properties, including a pseudoplastic behavior. The FTIR spectra of cross-linked hydrogels revealed interactions between alginate and Ca⁺², referred to as the egg-box model, indicated by the decrease in peaks at 1600 and 1410 cm⁻¹. Furthermore, the hydrogel loaded with ketoconazole showed remarkable antifungal activity against C. neoformans strains indicated by inhibition zones, which cross-linking did not seem to affect its antifungal performance. The developed material remained structurally stable for up to 12 days (288 h) in swelling studies, and preliminary cytotoxicity performed with V79 cells indicates potential for in vivo studies and topical application.

The development of multifunctional cotton fabrics that are stain-resistant, antimicrobial, and easy to clean has sparked scientific interest as well as practical usefulness, owing to its medical and healthcare applications. The purpose of this study was to fabricate self-cleaning and antimicrobial cotton for final use by soaking the cotton fabric in nonfluorinated hybrid formulations based on quaternary chitosan-silane using the sol–gel process. The fluorine-free cotton fabric demonstrated high self-cleaning behavior and outstanding bacterial killing efficacy against E. coli and S. aureus bacteria, without altering the desired textile properties of cotton fabric. Remarkably, cotton textiles using the hybrid formulations HTACC-VTES (N-(2-hydroxy)propyl-3-trimethylammonium chitosan chloride-vinyltriethoxy silane) and TMCC-VTES (N, N, N-trimethyl chitosan chloride–vinyltriethoxy silane) demonstrated promising water contact angles of 147° and 142° respectively, indicating a move toward superhydrophobicity. In FTIR spectra, both treated cotton textiles had an absorption peak at 1208 cm⁻¹ (SiOC bending), indicating a stronger interaction between silane binding agents and the cotton substrate. The treated cotton fabric with desirable features retains its stability and endurance after 12 cycles of washing for antibacterial tests and 15 cycles for wettability tests. The manufactured cotton fabric has several potential applications, such as in personal hygiene items and medical applications.

The utilization of nanoformulations derived from natural products for the treatment of many human diseases, including cancer, is a rapidly developing field. Conventional therapies used for cancer treatment have limited efficacy and a greater number of adverse effects. Hence, it is imperative to develop innovative anticancer drugs with superior effectiveness. Among the diverse array of natural anticancer compounds, resveratrol, curcumin, and epigallocatechin gallate (EGCG) have gained considerable attention in recent years. Despite their strong anticancer properties, medicinally significant phytochemicals such as resveratrol, curcumin, and EGCG have certain disadvantages, such as limited solubility in water, stability, and bioavailability problems. Encapsulating these phytochemicals in poly(lactic-co-glycolic acid) (PLGA), a polymer that is nontoxic, biodegradable, and biocompatible, is an effective method for delivering medication to the tumor location. In addition, PLGA nanoparticles can be modified with targeting molecules to specifically target cancer cells, thereby improving the effectiveness of phytochemicals in fighting tumors. Combining plant-based medicine (phytotherapy) with nanotechnology in a clinical environment has the potential to enhance the effectiveness of drugs and improve the overall health outcomes of patients. Therefore, it is crucial to have a comprehensive understanding of the different aspects and recent advancements in using PLGA-based nanocarriers for delivering anticancer phytochemicals. This review addresses the most recent advancements in PLGA-based delivery systems for resveratrol, EGCG, and curcumin, emphasizing the possibility of resolving issues related to the therapeutic efficacy and bioavailability of these compounds.

This investigation validated iodine binding in combination with lintnerization for studying the structural nature of the amorphous areas in starch granules. Lintners of four iodine vapor-stained and non-stained amylose-containing starches and their waxy counterparts were analyzed by high-performance anion-exchange chromatography (HPAEC). The composition of the lintners was strongly affected by the absence of amylose in barley and potato starch but not in maize and cassava starch. Iodine-stained waxy lintners possessed increased number of long B2 chains. β-Limit dextrins of the lintners were very variable in composition. Iodine inclusion complexes washed out from the granular residues in the lintners (mostly from amylose-containing barley and maize starches) were also analyzed. Acid-soluble complexes from both amylose-containing and waxy starches possessed a lot of material with a degree of polymerization (DP) around 60 and a periodicity in size of DP 8–12. Such long chains were only minor components in water-soluble complexes of amylose-containing barley and maize starch lintners, and they lacked the size periodicity. Models of the principal structure of the acid and water-soluble complexes are suggested. It is concluded that acid hydrolysis of iodine-stained starch granules is a useful tool in structural analyses of the molecular composition of amorphous parts of starch granules.

In recent years, hydrogels have found a special place in regenerative medicine for tissue repair, rehabilitation, and drug delivery. To be used in regenerative medicine, hydrogels must have desirable physical, chemical, and biological properties. In this study, a new biomonomer based on hydroxyethyl methacrylate-succinic acid-polyethylene glycol 200 (HEMA-Suc-PEG) was synthesized and characterized. Then, using the synthesized monomers and different ratios of polyethylene glycol diacrylate (PEGDA) as a crosslinker, biocompatible hydrogels were synthesized through thermal and UV curing methods. The mechanical, physical, chemical, and biological properties of the hydrogels and the behavior of endothelial cells, an essential component of the cardiovascular system, were evaluated. The results showed that the hydrogel synthesized with 0.2 g of PEGDA (UV curing) has desirable mechanical and physical properties. Biological tests showed that these hydrogels are not only nontoxic to cells but also enhance cell adhesion. Therefore, the hydrogel containing the synthesized monomer HEMA-Suc-PEG and 0.2 g of PEGDA has the potential to be used in the cardiovascular system.

Potential therapies for wound management remain one of the most challenging affairs to date. Biopolymer hydrogels possess inherent properties that facilitate the healing of damaged tissue by creating a supportive and hydrated environment. Chitosan/fibroin hydrogels were formulated with poly (vinyl pyrrolidone) and cross-linked using 3-aminopropyl (diethoxy) methylsilane (APDEMS) for the aforementioned function. The hydrogels were characterized through Fourier transform infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy, and their swelling response was observed using a variety of solvents. Additionally, hydrogels were investigated for biomedical applications. As the amount of fibroin added to the hydrogels increased, the swelling ratio decreased. The analysis of chorioallantoic membrane (CAM) assay revealed that higher concentrations of fibroin in the hydrogel were directly correlated with increased angiogenesis. The intragroup comparison showed that the vascular number in the CPF5 group was significantly increased (p ≤ 0.05) compared to other hydrogel groups. The wound healing efficiency of the prepared hydrogels showed that the rate of wound reduction (99.06%) was remarkably (p ≤ 0.05) high in the hydrogel group with a greater fibroin content against control (67.03%). Histological findings of wounded tissues corroborate the abovementioned results, showing dense fibrous connective tissues in the fibroin group compared to the control. The results of this work provide thorough preclinical evidence that chitosan-fibroin biopolymers are involved in enhanced angiogenesis in growing chicks and speed up wound healing in mice without any obvious toxicity.