Hauserhauser8689

Agar, a gelatinous polysaccharide which is in the cell wall of many red algae, is widely used as food and gelling agent. Agar oligosaccharides (AOs), the hydrolysate of agar, show much more kinds of bio-activities because of its lower molecular weight, better water solubility and higher absorption efficiency. It is indicated that AOs with different structure and degree of polymerization, i.e. series of agaro-oligosaccharides and neoagaro-oligosaccharides, can be obtained under different preparation conditions. In addition, the biological activities of AOs are diversely and closely correlated to the composition and structure. This review aims to comprehensively summarize the preparation, structural characteristics and bio-activities of AOs, so as to provide a reference for applications of AOs as marine natural products in pharmacological, cosmetics and nutraceutical fields.Natural polysaccharides are attractive materials for fabrication of eco-friendly biodsorbents for efficient water remediation. However, scarcity of adsorbents that possess features of high stability and adsorption capacity at various pH conditions, low-cost, eco-friendly, and recycleability at the same time still remains a great challenge. Herein, porous ionically crosslinked biofoams were prepared by freeze-drying of chitosan (CS)/sodium alginate (SA) complex (CSA). FTIR and XRD were used to characterize the structure of the bioadsorbents. SEM observations revealed that adsorbents have a 3D interconnected porous structure, which is a favorable morphology for dye adsorption. Accordingly, CSA and its nanocomposite containing 15 wt% cellulose nanofibers (CSAC15) exhibited a fast and efficient adsorption behavior with qm values of 2015 and 2297 mg/g for adsorption of the Eriochrome black-T (EBT) anionic dye, respectively, which are quite outstanding among the developed EBT adsorbents in the literature so far. The CSAC15 preserved its stability and high adsorption capacity at various pH solutions. The adsorption of EBT onto the bioadsorbents was well-described with the pseudo-second order kinetics and Freundlich isotherm. The proposed CSAC15 bioadsorbent featured repeated dye removal capability after five cycles of adsorption.A novel and eco-friendly chitosan derivative was synthesized as green corrosion inhibitors on C3003 aluminum alloy in 3.5 wt.% NaCl solution. In this paper, CP was prepared by Schiff Base reaction with chitosan and 4-pyridinecarboxaldehyde. Then, TiO2 was dispersed in CP to prepare CPT nanocomposite. The corrosion inhibition effect of CPT on C3003 aluminum alloy at different concentrations were studied with electrochemical techniques and surface analysis. The results showed that the maximum inhibition efficiency of CPT nanocomposite reaches to 94.5 % at 200 ppm after the immersed in 3.5 wt.% NaCl solution for 72 h. Meanwhile, the contact angle increases to 120° due to the formation of hydrophobic substances. The strategy of organic/inorganic hybrid can provide the inspiration for the development of chitosan corrosion inhibitor with low concentration and high efficiency.Plant fungal diseases can lead to yield reduction and quality degradation in crops, which usually cause serious economic losses. Additionally, chemical fungicides used in the prevention and control of plant diseases are increasingly restricted due to resistance development and high toxicity. Therefore, biogenic fungicides such as chitosan with low toxicity and good biocompatibility are receiving increasing attention. This study found that the acid swelling chitosan pretreatment method can accelerate the rate of the specific oxidation of chitosan catalyzed by the TEMPO-NaBr-NaOCl system. This study proved that OCTS induces plant disease resistance, and the control efficiencies achieved in protection and treatment experiments against Botrytis cinerea were 80.6 % and 83.4 %, respectively, at 400 μg/mL OCTS. In addition, OCTS can promote plant growth and enhance plant defense enzyme activities. This research has realized a forward-looking exploration of the application of OCTS in the agricultural field.The present study was focused on investigation of electrokinetic behaviour of lecithin-stabilized oil/water emulsions in the presence of chitosan oligosaccharides (COS). The oligosaccharides give unique opportunity for precisely characterization of the properties of chitosan as a function of the degree of acetylation (DA) and degree of polymerization (DP) of the polymer. For the study were chosen well characterized ultra pure COS molecules with completely acetylated monomers and mixture of COS molecules with acetylated and deacetylated monomers. The obtained results confirmed experimentally for the first time, the suggestion for the predominant contribution of hydrophobic (at high DA) and electrostatic (at low DA) interactions between chitosan monomers and the lecithin-covered droplet surface.Spontaneous formation of protein corona on chitosan-based nano-carriers is inevitable once they enter the blood, which is considered to be an important factor that weakens the delivery efficiency and therapeutic effect of nucleic acid drugs. For this, cyclic RGDyK peptide (cRGD) modified bovine serum albumin (BSA) was designed as a corona to precoat on redox-responsive chitosan-based nano-carriers (TsR NPs) before administration. The effects of the precoating corona on the pharmaceutical properties and delivery efficiency of the nano-carriers and the therapeutic effect of model siRNA (siVEGF) were investigated. The results showed that BSA-cRGD formed steady corona around TsR NPs, which enhanced targeting ability to cancer cells and reduced serum proteins adsorption. The Bc corona improved the stability and biocompatibility of TsR NPs, increased the intracellular uptake, facilitated the lysosomal escape and maintained their redox-sensitive responsiveness, resulting in enhanced gene silencing efficiency and anti-tumor proliferation effects both in vitro and in vivo.Potato is a major food crop with enormous biomass straw, but lignocellulose recalcitrance causes a costly bioethanol conversion. Here, we selected the cytochimera (Cyt) potato samples showing significantly-modified lignocellulose and much increased soluble sugars and starch by 2-4 folds in mature straws. Under two pretreatments (8 min liquid hot water; 5% CaO) at minimized conditions, the potato Cyt straw showed complete enzymatic saccharification. Further performing yeast fermentation with all hexoses released from soluble sugars, starch and lignocellulose in the Cyt straw, this study achieved a maximum bioethanol yield of 24 % (% dry matter), being higher than those of other bioenergy crops as previously reported. https://www.selleckchem.com/products/AZD0530.html Hence, this study has proposed a novel mechanism model on the reduction of major lignocellulose recalcitrance and regulation of carbon assimilation to achieve cost-effective bioethanol production under optimal pretreatments. This work also provides a sustainable strategy for utilization of potato straws with minimum waste release.