CO2N2 Gas Separating Utilizing PebaxZIF7PSf Composite Walls

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A homogeneous polysaccharide named SHNP with apparent molecular weight of 8.4 kDa was purified from brown algae Sargassum henslowianum using ethanol precipitation, ion-exchange chromatography, and gel-filtration column chromatography. Structural analyses reveal that SHNP is completely composed of glucose, and its backbone consists of β-D-(1→3)-Glcp with side chains comprising t-β-D-Glcp attached at the O-6 position. Thus, SHNP is a laminarin-type polysaccharide. In vitro fermentation test results showed that SHNP was digested by gut microbiota; the pH value in the fecal culture of SHNP was significantly decreased; and total short-chain fatty acids, acetic, propionic and n-butyric acids were significantly increased. Furthermore, SHNP regulated the intestinal microbiota composition by stimulating the growth of species belonging to Enterobacteriaceae while depleting Haemophilus parainfluenzae and Gemmiger formicilis. Taken together, these results indicate that SHNP has the potential for regulating gut microbiota, but its specific role in the regulation requires to be further investigated.Pectins are a part of daily diet as well as food additives that are indigestible polysaccharides by human enzymes, however, they can be easily degraded by gut bacteria with the production of short chain fatty acids (SCFAs). Knowledge of pectin gut homeostasis and further how pectin affect gut bacterial communities is insufficient and limited. This review focuses on providing the whole story of how pectin functions as prebiotics in the gut. Understanding the interplay between functional and immunological responses inside animal or human gut as influenced by pectin in diets is provided. The interaction between pectin and gut microbiota is presented from both sides, in terms of how pectin affects gut microbiome and or the fermentation products produced in response by gut bacteria. This knowledge can be used to define preferred dietary pectins, targeting beneficial bacteria, and favoring balanced microbiota communities in the gut to maximize pectins' health benefits.In this work, carbon dot (CD) was in-situ synthesized and attached to cellulose nanofiber (CNF) via hydrothermal process. The in-situ synthesized CD uniformly enveloped the CNF surface by means of amide bonding, without significant changes of the chemical structure of CNF. The prepared CD@CNF composite showed rough and bumpy morphology. The attached CD increased the interaction between the fibers and enhanced the thermal stability and the dimensional stability in aqueous solution. CD@CNF showed excellent performance as a dye-rejection membrane with high-water flux (∼32 LMH bar-1) and high rejection rate (∼99.8 %), as well as the selective removal of cationic dye. This study suggests a novel synthesizing method of durable CNF membrane by envelopment of CD for effective water treatment.Cellulose and TEMPO-oxidized cellulose fibers (TOCF) from the wheat straw were prepared with ultrasonic and chemical treatments to investigate structure and functionalities. Sol-gel transition of TOCF suspensions has been investigated using rheology to unveil the roles of ultrasonic pretreatment and temperature at various concentration. It was found that TOCF extracted with or without ultrasonic pretreatment exhibit similar functional groups in FTIR. learn more However, different crystal structures and thermal stabilities were revealed in XRD and TGA, respectively. The gelation was independent of the ultrasonic pretreatment, while the rheological properties were highly infuenced by the concentration and temperature of the TOCF suspensions. TOCF suspensions presented a strain thinning behavior in large amplitude oscillatory shear tests. Lissajous curves showed that the elastoplastic behavior was predominantly modulated by the fiber concentration and strain amplitude other than the ultrasonic pretreatment. These results could improve the understanding of the relationships between TOCF structure and rheological properties.Graphene displays various properties like optical, electrical, mechanical, etc. resulting in a large range of applications in biosensing, bio-imaging, medical and electronic devices. The graphene-based nanomaterials show disadvantages like hydrophobic surface, degradation of biomolecules (proteins and amino acids) and toxicity to the human and microbes by permeating into the cells and thus, limiting the use in the biomedical field. Conjugation of carbohydrates like chitin, cyclodextrins and cellulose with graphene results in thermal stability, oxygen repulsive ability, fire-retardant and gelling properties with better biodegradability, biocompatibility and safety leading to the formation of environment-friendly biopolymers. This article delivers an overview of the molecular interaction of different carbohydrates-derived from natural sources like marine, plants and microbes with graphene nanosheets to extend the applications in tissue engineering, surgical materials, biosensing and novel drug delivery for prolonged action in the treatment of breast and hepatic cancers.Prebiotics are known for their ability to modulate the composition of the human microbiome and mediate health-promoting benefits. Endo-levanases, which hydrolyze levan into short-chain FOS, could be used for the production of levan-based prebiotics. The novel endo-levanase (LevB2286) from Azotobacter chroococcum DSM 2286, combines an exceptionally high specific activity with advantageous hydrolytic properties. Starting from levan isolated from Timothy grass, LevB2286 produced FOS ranging from DP 2 - 8. In contrast to endo-levanases described in the literature, LevB2286 formed minor amounts of fructose and levanbiose, even with greatly extended incubation. The combined activity of LevB2286 and the levansucrase LevS1417 from Gluconobacter japonicus LMG 1417 led to a one-step synthesis of levan-type FOS from sucrose. 387.4 ± 17.3 g L-1 FOS were produced within 48 h by the production strategy based on crude cell extract of recombinant Escherichia coli expressing levS1417 and levB2286 simultaneously.Cellulose nanofibrils were efficiently produced from eucalyptus fibers using a combined NaOH and enzymatic treatment followed by a pilot scale grinding process. The structural changes of fibers were assessed after NaOH treatments at 5, 10 and 15 wt% concentrations. A progressive shift from a cellulose I to a cellulose II crystalline structure was observed with X-ray diffraction (XRD) and nuclear magnetic resonance (NMR). The further enzymatic hydrolysis was improved for the NaOH treated samples. The increase of crystallinity indices due to enzymatic hydrolysis was of + 4.7 %, + 3.5 %, and +10.3 % for samples treated with NaOH 5, 10 and 15 wt% respectively, and DP values were drastically reduced to 340, 190 and 166 respectively. A morphological analysis underlined an optimum with the combination of NaOH 10 wt% and enzymatic hydrolysis. This treatment followed by the grinding process resulted in CNF with a rigid structure, with diameters ranging from 10 to 20 nm and lengths between 150 and 350 nm. A multi-scale analysis enabled to study the impact of this combined treatment on CNF properties and energy consumption.