Wallerbarnes8448

Here, a simple and efficient strategy to produce porous and hydrophilic chitosan/cellulose sponge using surfactant and pore-forming agent is demonstrated. The preparation of composite sponge by LiOH/KOH/urea solvent system effectively solve the problems of uneven distribution of chitosan, poor softness and acid residue caused by soaking in chitosan acid solution. The obtained chitosan/cellulose sponges exhibit high water absorption capacity and rapid shape recoverability, as well as good mechanical properties. Effective inhibitory on Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa are particularly proved. Besides, the result of the dynamic whole blood clotting time indicated that the chitosan/cellulose composite sponge has better coagulation ability than those of traditional gauze and gelatin sponge. Animal experiment further showed that rapid hemostasis within 34 s can be reached with the composite sponge. Better biocompatibility of the composite sponge is proved by the results of hemocompatibility and cytotoxicity, indicating an excellent candidate for rapid hemostasis in massive haemorrhage.Green biocomposites based on corn starch plasticized with isosorbide and glycerol and filled with microcrystalline cellulose (MCC) were processed. The structural interactions, dynamomechanical properties, water absorption, and soil biodegradability were investigated by different techniques considering the effect of the type and amount of plasticizer and the MCC addition. The changes along the time of the structural interactions and the dynamomechanical properties of these materials and the influence of the retrogradation phenomenon were also studied. The use of isosorbide as plasticizer instead of glycerol improved the stiffness, the water absorption and the biodegradation rate of thermoplastic starch (TPS). Moreover, no evidence of retrogradation for isosorbide was observed. An isosorbide content of 35% and the addition of MCC filler enhanced in a greater extent these properties with a complete biodegradability in 7 month. These green biocomposites can be an alternative for food packaging applications.Basil seeds are widely cultivated throughout the world because of their extensive applications in various fields of life. The Basil seeds mucilage (BSM) exhibits remarkable physical and chemical properties like high water absorbing capacity, emulsifying, and stabilizing properties. The extraction of this mucilage from the seed surface has always been done by physical and chemical methods, which has certain drawbacks. Here, we report for the first time a chemical method for the effective extraction of this mucilage using ionic liquids (ILs); the green solvents. Pyridinium chloride based ILs were investigated for the effective extraction of mucilage and the process was optimized for various variables i.e. time, temperature, basil seed loading, co-solvents, anti-solvents. The extraction yield (up to 25% w/w of mucilage per basil seeds dry weight) was obtained at optimum conditions. Extracted mucilage was characterized by analytical techniques. The extracted BSM was used to prepare AuNps/BSM nanocomposite by stabilizing the gold nanoparticles. The AuNps/BSM nanocomposite was applied for the catalytic degradation of dyes (congo red; 12 min, methyl orange; 4 min, whereas 4-nitrophenol; 6 min).Removal of organic pollutants such as aromatic nitro compounds and dyes from wastewaters is very significant for environment, and the best strategy is their reduction/degradation in the presence of a metal catalyst. In this study, a new palladium nanocatalyst (GA-Sch-Pd) was prepared derived from modified gum arabic and characterized by FT-IR, TGA, FE-SEM, EDS, TEM, and XRD analyses. Then, the catalytic potential of GA-Sch-Pd nanocatalyst was tested in the catalytic reductions of different organic pollutants such as o-nitroaniline (o-NA), p-nitrophenol (p-NP), p-nitro-o-phenylenediamine (p-NPDA), p-nitroaniline (p-NA), congo red (CR), methylene blue (MB), and methyl orange (MO) by using NaBH4 in water. These tests showed GA-Sch-Pd nanocatalyst had high activity against reduction of nitroarenes and organic dyes at very short reaction durations. Moreover, GA-Sch-Pd nanocatalyst was easily separated and reused for several times. This study shows that GA-Sch-Pd nanocatalyst has a high potential for remediation of environmental pollutants in wastewaters.Bacteriocins are a subclass of antibacterial peptides considered to be the most promising alternative to antibiotics. A large number of unknown bacteriocins are hidden in lactic acid bacteria. In this study, by combining the genome with LC-MS/MS, 14 novel bacteriocins produced by Lactobacillus rhamnosus LS-8 were detected. Moreover, these bacteriocins were successfully cloned via plasmid pET-28a(+) and pET-30a(+) and heterologously expressed in Escherichia coli BL21. Escherichia coli ATCC25922 and Staphylococcus aureus ATCC25923 were used to confirm their antibacterial activity. Subsequently, the four bacteriocins (pH 25, S68, S81, and S137) with the strongest antibacterial ability were selected, and their expression conditions were optimized. Purification was performed by cation exchange chromatography and high performance liquid chromatography, and the active parts were collected and analyzed by mass spectrometry. The mass spectrometry analysis revealed that peptide coverage was >71.39%. The MICs of the four bacteriocins against four pathogenic bacteria ranged from 5.38 to 19.84 μg/mL. In addition, these bacteriocins significantly inhibited the growth of four standard pathogenic bacteria. They also exhibited broad-spectrum bacteriostasis on Gram-positive and Gram-negative bacteria. Therefore, these new bacteriocins have great potential in the study of alternative antibiotics.There is an array of methodologies to prepare nanocellulose (NC) and its fibrillated form (CNF) with enhanced physicochemical characteristics. However, acids, bases or organosolv treatments on biomass are far from green, and seriously threaten the environment. Current approach to produce NC/CNF from biomass should be revised and embrace the concept of sustainability and green chemistry. Although hydrothermal process, high-pressure homogenization, ball milling technique, deep eutectic solvent treatment, enzymatic hydrolysis etc., are the current techniques for producing NC, the route designs remain imperfect. Herein, this review highlights the latest methodologies in the pre-processing and isolating of NC/CNF from lignocellulose biomass, by largely focusing on related papers published in the past two years till date. This article also explores the latest advancements in environmentally friendly NC extraction techniques that cooperatively use ball milling and enzymatic hydrolytic routes as an eco-efficient way to produce NC/CNF, alongside the potential applications of the nano-sized celluloses.Herein, the natural extract of garlic, allicin (Alli), was added into chitosan (CS)/polyvinyl alcohol (PVA)/graphene oxide (GO) composites to develop the nanofibrous membranes with strong antibacterial activity and sustained-release properties by electrospinning technology. Vitro Alli release test showed that the release rate and amount of Alli could be regulated by the content of GO in the nanofibrous membrane. The antibacterial activity test against Staphylococcus aureus was performed and revealed the antibacterial activity of nanofibrous membranes loading with Alli. SCR7 price Compared with the nanofibrous membrane without GO, the CS/PVA/Alli nanofibrous membrane with 0.1 wt% GO still had nice antibacterial activity after 48 h. The water contact angle of nanofibrous membranes dropped significantly with the addition of GO and Alli, which showed the nanofibrous membrane had highly hydrophobic. The CS/PVA/GO nanofibrous membrane loading with Alli had great hygroscopicity and moisture-retention capacity. The essential characteristics of nanofibrous membranes were evaluated by SEM, FTIR, XRD. link2 The above results indicate that the membrane has a strong antimicrobial activity and long-lasting efficacy, so the developed natural nanofibrous membranes hold potential as promising antibacterial wound dressing and tissue engineering.Hydrogels derived from silk fibroin (SF) are attractive soft materials in biomedical applications such as drug delivery and tissue engineering. link3 However, SF hydrogels reported so far are generally brittle in tension limiting their load-bearing applications. We present here a novel strategy for preparing stretchable SF hydrogels by incorporating flexible polymer chains into the brittle SF network, which strengthen the interconnections between SF globules. We included N, N-dimethylacrylamide (DMAA) monomer and ammonium persulfate initiator into an aqueous SF solution containing a diepoxide cross-linker to in situ generate flexible poly (N,N-dimethylacrylamide) (PDMAA) chains. Moreover, instead of SF, methacrylated SF was used for the gel preparation to create an interconnected SF/PDMAA network. The free-radical polymerization of DMAA leads to the formation of PDMAA chains interconnecting globular SF molecules via their pendant vinyl groups. Incorporation of 2 w/v% DMAA into the SF network turns the brittle hydrogel into a stretchable one sustaining up to 370% elongation ratio. The mechanical properties of SF hydrogels could be adjusted by the amount of PDMAA incorporated into the SF network. The stretchable and tough SF hydrogels thus developed are suitable as a scaffold in tissue engineering and offer an advantage as a biomaterial over other SF-based biomaterials.We formulated a traditional Chinese medicine (TCM) prescription, Hanshiyi Formula (HSYF), which was approved and promoted by the Wuhan Municipal Health Commission for treating mild and moderate coronavirus disease 2019 (COVID-19). We aimed to evaluate the effect of HSYF on the progression to severe disease in mild and moderate COVID-19 patients. We conducted a retrospective cohort study of patients with mild and moderate COVID-19 in a quarantine station in Wuchang District, Wuhan. Using the real-time Internet information collection application and Centers for Disease Control for the Wuchang District, patient data were collected through patient self-reports and follow-ups. HSYF intervention was defined as the exposure. The primary outcome was the proportion of patients who progressed to a severe disease status, and a stratification analysis was performed. Univariate and multivariate regression analyses were performed to identify influencing factors that may affect the outcome. Further, we used propensity score matching (PSM) to assess the effect of HSYF intervention on the conversion of mild and moderate to a severe disease status. Totally, 721 mild and moderate COVID-19 patients were enrolled, including 430 HSYF users (exposed group) and 291 non-users (control group). No cases in the exposed group and 19 (6.5 %, P 48 years) [odds ratio (OR) 1.044; 95 % CI 1.001-1.088; P = 0.044] were independent risk factors for conversion to severe disease. Therefore, HSYF can significantly reduce the progression to severe disease in patients with mild and moderate COVID-19, which may effectively prevent and treat the disease. However, further larger clinical studies are required to verify our results.