Preparation of chitooligosaccharides from chitosan by a complex enzyme

Production and Characterization of Partially Purified Chitosanase Enzyme of <i>Bacillus cereus</i> A4/B4 Isolated from Biowaste Soil Samples:Bioactive Chitooligosaccharide

“…Liu et al [16] reported that the chitooligosaccharide dissolved in water, ethanol, ethyl acetate and glacial acetic and not in diethyl ether where as in the present investigation the chitooligosaccharide dissolved only in water.…”

“…The reaction was stopped by heating at 100°C for 5minutes and after cooling the mixture was mixed with 0.25M of sodium hydroxide and was centrifuged for 20 minutes at 1,000 X g. The supernatant chitooligosaccharides was collected [15]. A portion of the mixture was mixed with concentrated alkali and precipitate formation was observed [16]. Then the aliquots were lyophilized.…”

The effects of chitosan oligosaccharide on the activation of murine spleen CD11c+ dendritic cells via Toll-like receptor 4

“…COS was prepared from enzymic hydrolysis chitosan according to our previous methods (Zhang et al, 1999). In brief, chitosan (5 g) was dissolved in 2% AcOH (100 ml), and then the pH of the solution was adjusted to 5.6.…”

“…Chitosan is the deacetylated derivative of chitin, and previous works revealed that chitosan plays a role in immune responses for plant and animal cells (Porporatto, Bianco, & Correa, 2005;Villiers et al, 2009). Chitosan oligosaccharide (Chitooligosaccharides, COS), derived from chitosan by enzymatic hydrolysis (Zhang, Du, Yu, Mitsutomi, & Aiba, 1999), is a new kind of biofunctional material which exhibits improved biological activities when compared with chitosan (Cho et al, 2008;Moon et al, 2007;Nam, Kim & Shon, 2007;PalmaGuerrero, Jansson, Salinas, & Lopez-Llorca, 2008;Rahman et al, 2008;Yoon, Moon, Park, Im, & Kim, 2007), such as inhibiting growth of bacteria and fungi, exerting anti-tumor activity, and acting as immunopotentiating effectors.…”

Metal-coordinating controlled oxidative degradation of chitosan and antioxidant activity of chitosan-metal complex

“…Enzymatic degradation (such as chitosanase, lipase, proteinase, polysaccharase), physical degradation (by X-ray, light, microwave), chemical methods, including acidic hydrolysis with some inorganic acid (such as HCl, HF, H 2 SO 4 , H 3 PO 4 , HNO 2 ) or some organic acid (such as HOAc, formic acid) and oxidative hydrolysis with oxidant (such as H 2 O 2 , O 3 , CH 3 COOOH), are the usual methods for chitosan degradation. [8][9][10][11][12][13][14][15][16] Except degradation with chitosanase, which can get chitosan oligomer with 6-8 glucose residues, other methods often produce the low molecular weight chitosan with large molecular weight distribution, and so the yield of low molecular weight chitosan with particular molecular weight is low. In addition, the degradation with chitosanase has some other restrictions, such as, the loss of chitosanase activity, difficult product separation, and so on.…”