The Microstructure, Antibacterial and Antitumor Activities of Chitosan Oligosaccharides and Derivatives

Chitosan obtained from abundant marine resources has been proven to have a variety of biological activities. However, due to its poor water solubility, chitosan application is limited, and the degradation products of chitosan oligosaccharides are better than chitosan regarding performance. Chitosan oligosaccharides have two kinds of active groups, amino and hydroxyl groups, which can form a variety of derivatives, and the properties of these derivatives can be further improved. In this review, the key structures of chitosan oligosaccharides and recent studies on chitosan oligosaccharide derivatives, including their synthesis methods, are described. Finally, the antimicrobial and antitumor applications of chitosan oligosaccharides and their derivatives are discussed.

Chitosan oligosaccharide alleviates the growth inhibition caused by physcion and synergistically enhances resilience in maize seedlings

The use of biopesticides has gradually become essential to ensure food security and sustainable agricultural production. Nevertheless, the use of single biopesticides is frequently suboptimal in agricultural production given the diversity of biotic and abiotic stresses. The present study investigated the effects of two biopesticides, physcion and chitosan-oligosaccharide (COS), alone and in combination, on growth regulation and antioxidant potential of maize seedlings by seed coating. As suggested from the results, physcion significantly inhibited the growth of the shoots of maize seedlings due to the elevated respiration rate. However, COS significantly reduced the growth inhibition induced by physcion in maize seedlings by lowering the respiration rate and increasing the content of photosynthetic pigments and root vigor, which accounted for lower consumption of photosynthesis products, a higher photosynthetic rate and a greater nutrient absorption rate. Thus, an improved growth was identified. As indicated from the in-depth research, the application of physcion and COS combination is more effective in down-regulated the malondialdehyde (MDA) content by facilitating the activities of the antioxidative enzymes (i.e., superoxide dismutase (SOD), catalase (CAT) and guaiacol peroxidase (G-POD)). Such results indicated that the combined use of physcion and COS neither affected the normal growth of maize seedlings, but also synergistically improved the antioxidant potential of the maize plants, resulting in plants with high stress resistance. Thus, the combined use of physcion and COS by seed coating in maize production has great potential to ensure yield and sustainable production of maize.

Removal of Pb(II) ions using Chitosan oligosaccharide/carboxymethyl cellulose/kaolin clay blend

Heavy metal removal from wastewater has become a major environmental concern around the world. The performance of a chitosan-oligosaccharide-based hybrid (chitosan oligosaccharide (COS)/Carboxymethyl cellulose (CMC)/Kaolin clay (KC) ternary blend material prepared in the presence of Glutaraldehyde (Glu) ternary blend material for the adsorptive removal of lead (Pb) from waterwaste was investigated in this study. The structure of COS with amine and hydroxyl groups helps to remove Pb ions. FTIR and X-Ray diffraction were used to characterize of COS/CMC/KC + Glu blend. The removal of ions was assessed using batch adsorption studies, which varied parameters such as the influence of beginning concentration, adsorbent dose, and contact time. The elimination of Pb ions by adsorption was pH-dependent, with a maximum at pH 5. The favorability of the reported experimental values was validated using several theoretical models such as Freundlich and Langmuir isotherms, pseudo-first-order and pseudo-second-order kinetics. The Langmuir isotherm and pseudosecond-order best fitted for the adsorption.