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  • Yildiz Arsenault posted an update 1 year, 6 months ago

    A neutral polysaccharide (LCPS) was obtained from Lobelia chinensis via hot water extraction and ethanol precipitation. After separation and purification, the homogeneous polysaccharide was obtained with a molecular weight of 2.6 × 103 Da. The chemical composition of the extracted polysaccharide contains fructose and glucose with protein-free identified by gas chromatography-mass spectrometer (GC-MS) method. Chemical structure of LCPS was indicated by nuclear magnetic resonance (NMR) spectroscopy. Data indicated that LCPS was an inulin-type fructan with α-D-Glcp-(1→[1)-β-D-Fruf-(2]15 linkage. LCPS intake reduced at significant level high fat diet (HFD)-induced body weight gain, liver weight, total cholesterol and triglyceride in serum and hepatic tissue, respectively. The lipid droplet accumulation in hepatic tissue was similar between lean and LCPS groups lower than in HFD-induced mice from tissue section staining results. Together, polysaccharides from Lobelia chinensis could be a new source of natural anti-obesity agent against obesity with potential value in the manufacturing supplements and drugs.A novel microwave-assisted green method that synchronously synthesizes silver nanoparticles (AgNPs) and AgNPs decorated holocellulose nanofibrils (AgNPs/HCNF) within a minute and without using a reducing agent is reported. As obtained nanomaterials were well characterized using various analytical techniques. AgNPs applied as a colorimetric probe for the selective recognition of Hg(II) (linear range 10-200 μg L-1, detection limit 1.16 μg L-1). The probe was able to quantify Hg(II) in spiked tap, bore, and lake water samples and paper strips were developed to facilitate the onsite detection. Furthermore, freeze-drying of the AgNPs/HCNF nanocomposite produced aerogel that served as an excellent catalyst for the reduction of Congo red and methylene blue. The aerogel was easily recovered and reused without a decrease in activity or deterioration of its structure for five cycles. These results indicate the great potential of the AgNPs/HCNF aerogel for waste water treatment and catalytic applications.Recently, graphene oxide(GO) has gained much attention for heavy metal removal due to its high surface area and lots of functional groups on the surface. However, GO itself in powder form is far away from practical adsorbents because it remains dispersed in liquid phase which causes difficulty in the separation from effluent. In this study, GO/carboxymethyl cellulose nanofibril (CMCNF) composite fiber(CF) is developed as an efficient and durable adsorbent. Cross-linked GO/CMCNF CF was continuously produced by employing Fe3+ ion as a coagulant during a typical wet-spinning process. Based on multiple interactions such as ionic bonding and electrostatic interactions between Fe3+ and carboxyl group on CMCNF, the CF exhibits enhanced mechanical property than pure GO fiber. GO/CMCNF-Fe3+ CF showed efficient lead (Pb2+) uptake with successful adsorbent recovery, which indicates durable and cost-competitive fiber type adsorbent for heavy metal ions.In this study, we found that a new artificial crystalline structure was fabricated from an amylose analog polysaccharide without hydroxy groups at the C-2 position, i.e., 2-deoxyamylose. The polysaccharide with a well-defined structure was synthesized by facile thermostable α-glucan phosphorylase-catalyzed enzymatic polymerization. Powder X-ray diffraction (XRD) analysis of the product indicated the formation of a specific crystalline structure that was completely different from the well-known double helix of the natural polysaccharide, amylose. Molecular dynamics simulations showed that the isolated chains of 2-deoxyamylose spontaneously assembled to a novel double helix based on building blocks with controlled hydrophobicity arising from pyranose ring stacking. The simulation results corresponded with the XRD patterns.The new coronavirus pneumonia, named COVID-19 by the World Health Organization, has become a pandemic. It is highly pathogenic and reproduces quickly. There are currently no specific drugs to prevent the reproduction and spread of COVID-19. Some traditional Chinese medicines, especially the Lung Cleansing and Detoxifying Decoction (Qing Fei Pai Du Tang), have shown therapeutic effects on mild and ordinary COVID-19 patients. Polysaccharides are important ingredients in this decoction. This review summarizes the potential pharmacological activities of polysaccharides isolated by hot water extraction from Lung Cleansing and Detoxifying Decoction, which is consistent with its production method, to provide the theoretical basis for ongoing research on its application.Twin-screw extrusion (TSE) is a rather recent method to produce cellulose nanofibrils (CNFs) at a high solid content under continuous feeding. Here, never-dried commercial eucalyptus pulp was used as starting material to produce CNFs by TSE after a chemical pretreatment to introduce carboxylic groups via TEMPO-mediated oxidation and carboxymethylation. Five samples with a carboxyl content ranging from 800 to 1300 μmol.g-1 were produced to explore how the carboxyl content affects the aptitude of cellulose fibers to be broken down to nanoscale. The properties of the resulting CNFs in terms of nanosized fraction, morphology and rheological properties were investigated. A critical carboxyl content of 700 μmol.g-1was a prerequisite for the successful conversion of cellulose fibers into a CNF gel by TSE, regardless the pretreatment method. The degree of swelling of the fibers was put forward to account for this critical parameter.In this study, the effect of bioreactor size was evaluated with respect to the production and characteristics of the nanocellulose membranes produced by two different bioreactors one with an 1800 cm2 cross-sectional area (BC-B44) and a lab-scale bioreactor with a 41 cm2 cross-sectional area (BC-B1). The culture conditions were kept the same, and the substrate consisted of overripe bananas, which are inexpensive because they are unsuitable for human consumption. The X-ray diffraction pattern showed that the two samples had similar crystalline structures, but changes were observed at the morphological level in the nanofibers that make up the BNC membranes. These changes generated, in turn, variations in the mechanical and thermal properties of the samples. click here This result represents a novel scale-up effect related to the static mode fermentation of BNC.