-
Houston Kring posted an update 11 hours, 29 minutes ago
Sulfonated cellulose nanocrystals (S-CNCs) can be used to encapsulate thyme white essential oil (EO) that is volatile and immiscible with water. S-CNCs form a Pickering emulsion (PE) with EOs and the micron-scale PEs are embedded in sodium alginate (SA) to form macroscale hydrogel beads. MER-29 order The incorporation of PEs with SA is confirmed with FTIR, XRD, SEM and confocal microscopic characterizations and the release behavior is monitored to understand the time-dependent biological activity of the EOs. The larvicidal performance of the SA-PE composite hydrogel beads is investigated with Aedes albopictus (Skuse) larvae. The larvicidal activity is higher for SA/PE hydrogel beads prepared at 0.5 % CaCl2 than 0.75 or 1.0 % CaCl2 due to their higher release rate.Two novel polysaccharides, namely CMPP-1 and CMPP-2, from kiwano (Cucumis metuliferus) peels were isolated through hot-water extraction, followed by ethanol precipitation and column chromatography. The results showed that CMPP-1 and CMPP-2 were hetero-galacturonans with different molecular weights of 7.35 kDa and 6.90 kDa, respectively. Both of CMPP-1 and CMPP-2 were mainly composed of glucuronic acid (45.93 % and 51.75 %, respectively), and other monosaccharides including rhamnose, arabinose, galactose, glucose, xylose, fucose, mannose, galacturonic acid, and mannuronic acid. The results of structural characterization from FT-IR and NMR confirmed that CMPP-1 and CMPP-2 were pectin with highly branched structure. Furthermore, both CMPP-1 and CMPP-2 possessed immune-enhancing activity and could enhance the secretion of nitric oxide and cytokines (TNF-α, IL-6) in a dose-dependent manner. Especially, CMPP-1 had higher immune activity than CMPP-2 as the minimum effective concentration were 0.78 μg/mL and 6.25 μg/mL, respectively. These findings provide a scientific basis for further utilization of polysaccharide from kiwano peels.Ti3C2Tx MXenes with excellent metallic conductivity have proved promising in its application of electromagnetic interference (EMI) shielding. A hierarchical hybrid film with ultrathin thickness composed of Ti3C2Tx MXene layers embedded with yarn-ball-shaped microspheres of cellulose nanofibrils (CNF) and multiwalled carbon nanotube (MWCNT) was designed to improve the absorption of electromagnetic waves (EMWs). The addition of yarn-ball-shaped microspheres is to shield more EMWs via multiple reflections in the inner space and reduce the undesirable emissions into the air. After thermal annealing treatment, the ultrathin film with intercalation of the carbonized yarn-ball-shaped CNF/MWCNT microspheres exhibited enhanced EMWs absorption as an important part of shielding effectiveness (45.1±0.9 dB) as well as excellent mechanical stability (≈0.9 million bending times). Thus, the well-designed structure of multilayered hybrid films with intercalated conductive microspheres can be a good candidate for higher absorption in EMI shielding effectiveness and outstanding mechanical properties.Pectin is natural biopolymer derived from various plant sources and its activity is driven by functional groups. Affinity of pectin and chemical interactions of the active sites to chemicals in media determines fate of adjuvant molecules. Pectin is appropriate co-polymer in modulation of drawbacks of other biopolymers such as low glass transition temperature, low water solubility, and susceptibility to human digestive tract. However, functionality of pectin is improved by its optimized complexation with other chemicals especially in food packaging and tissue engineering. In the last decade, several technical and health-related functions of pectin have been studied through which some products designed and marketed progressively. Pectin-based formulations were commercialized in food, medicine, and radioprotection sectors. It is also advised for alleviation of constipation symptoms. Cost-effectiveness of this multifunctional biopolymer compared to the others that are currently used, has introduced it as a potential alternative for the next years.Capsular polysaccharides (CPS) are the key virulent factors in the pathogenesis of Streptococcus pneumoniae. The previously unknown CPS structures of the pneumococcal serotype 28F and 28A were thoroughly characterized by NMR spectroscopy, chemical analysis and AF4-MALS-dRI. The following repeat unit structures were determined -4)[α-l-Rhap-[4-P-2-Gro]]-(1-3)-α-d-Sug-[6-P-Cho]-(1-3)-β-l-Rhap-[2-OAc]-(1-4)-β-d-Glcp-(1-; 28F Sug = Glcp, Mw 540.5 kDa; 28A Sug = GlcpNAc, Mw 421.9 kDa; The correlation of CPS structures with biosynthesis showed that glycosyltransferase WciU in serotypes 28F and 28A had different sugar donor specificity toward α-d-Glcp and α-d-GlcNAcp, respectively. Furthermore, latex agglutination tests of de-OAc and de-PO4 CPS were conducted to understand cross-reactions between serogroup 28 with factor antiserum 23d. Interestingly, the de-OAc 28F and 28A CPS can still weakly react with factor antiserum 23d, while de-PO4 CPS did not react with factor antiserum 23d. This indicated that OAc group could affect the affinity and P-2-Gro was crucial for cross-reacting with factor antiserum 23d.In this study, hydric and biodegradability properties of cassava starch-based bioplastics reinforced with crude kaolin or treated kaolinitic clay at 700 °C called metakaolin were investigated using water adsorption and microbiological tests. Non-reinforced bioplastics (BP) and those containing 5 wt.% crude kaolin (BPKB) or metakaolin (BPMKB) were manufactured using the casting/evaporation method. Results obtained showed a decrease in the solubility and in the water diffusion and permeability of clay-reinforced bioplastics with respect to the ones without reinforcement. This improvement of the hydric properties has been attributed to the reduction in the free volumes existing between the starch macromolecules due to their interactions with clay platelets. These interactions might favor a more homogeneous and compact microstructure. The biodegradability of the clay reinforced bioplastics was significantly improved due to the bacterial proliferation. The thermal treatment of kaolinitic clay further improved the hydric and biodegradability properties of starch-based bioplastics.