Enzymic preparation of water-soluble chitosan and their antitumor activity

Qin, Caiqin; Du, Yumin; Xiao, Ling; Liu, Zhan; Gao, Xiaohai

doi:10.1016/s0141-8130(02)00064-8

Cited by 279 publications

(136 citation statements)

References 25 publications

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“…Slits were programmed to yield 10 Å (1 Å = 10 −10 m) bandwidth at each wavelength so that the resolution was more or less constant. The spectra were recorded between 200 and 240 nm and baseline was obtained using 0.1 M HClO 4 . After accumulation of scans, the spectra were standardized to mean residual ellipticity expressed as θ in degree · cm 2 per residue using the mean residual mass of GlcNAc [17].…”

Section: CDmentioning

confidence: 99%

“…In spite of its abundance and various biofunctionalities, utilization of chitosan is restricted, owing to its high molecular mass, high viscosity and, thus, low absorption for in vivo applications [2]. Recent studies on chitosan depolymerization have drawn considerable attention, since the products obtained are easily water-soluble and also possess versatile biofunctional properties such as antitumour [3][4][5], immuno-stimulating [2] and antimicrobial activities [6,7] and are being used for alleviating problems due to osteoarthritisgastritis [8].…”

Section: Introductionmentioning

confidence: 99%

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Characterization of chito-oligosaccharides prepared by chitosanolysis with the aid of papain and Pronase, and their bactericidal action against Bacillus cereus and Escherichia coli

Kumar

Varadaraj

Gowda

et al. 2005

Biochemical Journal

201

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Papain (from papaya latex; EC 3.4.22.2) and Pronase (from Streptomyces griseus; EC 3.4.24.31) caused optimum depolymerization of chitosan at pH 3.5 and 37• C, resulting in LMMC (low molecular mass chitosan) and chito-oligomeric-monomeric mixture. The yield of the latter was 14-16 % and 14-19 % respectively for papain-and Pronase-catalysed reactions, depending on the reaction time (1-5 h). HPLC revealed the presence of monomer(s) and oligomers of DP (degree of polymerization) 2-6, which was also confirmed by matrix-assisted laser-desorption ionization-time-of-flight MS. Along with the chito-oligomers, the appearance of only GlcNAc (N-acetylglucosamine) in Pronasecatalysed chitosanolysis was indicative of its different action pattern compared with papain. Fourier-transform infrared, liquidstate 13 C-NMR spectra and CD analyses of chito-oligomericmonomeric mixture indicated the release of GlcNAc/GlcNAc-rich oligomers. The monomeric sequence at the non-reducing ends of chito-oligomers was elucidated using N-acetylglucosaminidase. The chito-oligomeric-monomeric mixture showed better growth inhibitory activity towards Bacillus cereus and Escherichia coli compared with native chitosan. Optimum growth inhibition was observed with chito-oligomers of higher DP having low degree of acetylation. The latter caused pore formation and permeabilization of the cell wall of B. cereus, whereas blockage of nutrient flow due to the aggregation of chito-oligomers-monomers was responsible for the growth inhibition and lysis of E. coli, which were evidenced by scanning electron microscopy analysis. The spillage of cytoplasmic enzymes and native PAGE of the cellfree supernatant of B. cereus treated with chito-oligomeric-monomeric mixture further confirmed bactericidal activity of the latter. Use of papain and Pronase, which are inexpensive and easily available, for chitosanolysis, is of commercial importance, as the products released are of considerable biomedical value.

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Section: CDmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Characterization of chito-oligosaccharides prepared by chitosanolysis with the aid of papain and Pronase, and their bactericidal action against Bacillus cereus and Escherichia coli

Kumar

Varadaraj

Gowda

et al. 2005

Biochemical Journal

201

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“…It is a polysaccharide widely distributed in nature as the principal component of exoskeletons of crustaceans and insects as well as of cell walls of some bacteria and fungi (Senel and McClure, 2004). Because of its unique polycationic nature, chitosan has been found to possess antifungal activity (Roller and Covill 1999) antibacterial activity (Helander et al 2001;Liu et al 2006) and antitumor activity (Qin et al 2001). Recently, the conversion of chitin and chitosan to oligosaccharides has attracted interest because oligosaccharides are not only water-soluble but also possess versatile functional properties such as antitumor activity, immuno-enhancing effects, enhancement of protective effects against infection with some pathogens, antifungal activity, and antimicrobial activity.…”

Section: Discussionmentioning

confidence: 99%

Effects of Chitosan-oligosaccharide on diarrhoea in Hanwoo calves

Alam¹,

Kim²,

Kim³

et al. 2012

Vet. Med.

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ABSTRACT:The therapeutic effect of Chitosan-oligosaccharide (COS) on calf diarrhoea was investigated in Korean native (Hanwoo) calves (n = 86). The calves were divided into two groups; the untreated/control (n = 40) having routine diet only and the treated group (n = 46) receiving COS (50 ml/day) in addition to the routine diet for five days. Blood samples from each animal were collected before and after five days treatment and were subjected to complete blood count (CBC), chemistry screening (CS) and plasma protein assay (PPA). The in vitro efficacy of COS against the most common causal agents of calf diarrhoea (Escherichia coli and Salmonella typhimurium) was evaluated. Among the CBC parameters a significantly higher total red blood cell count (tRBC), haemoglobin (Hb) and packed cell volume (PCV) were noticed in the untreated group. In the CS parameters higher levels of blood urea nitrogen (BUN), creatinine and total bilirubin (TBL), and lower glucose were found in the untreated group. Significantly higher levels of albumin and α-globulin along with lower γ-globulin were noted in the untreated group. Among the treated group 41 (out of 46) calves recovered completely from diarrhoea and in the untreated group five calves (out of 40) spontaneously recovered after five days, revealing that the COS has a good therapeutic effect on diarrhoea in calves. The COS was found to effectively inhibit bacterial growth and pathogenicity up to 1:64 and 1:256 dilutions in the case of S. typhimurium and E. coli respectively. The results of this study revealed that the levels of different parameters of CBC (tRBC, Hb, PCV), CS (BUN, creatinine, TBL) and PPA (albumin, α-globulin, γ-globulin) profiles can reflect the severity of diarrhoea and dehydration and that COS can be successfully used for the clinical management of diarrhoea in Hanwoo calves.

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“…Lipophility is one of the most important physicochemical parameters of the active molecules expressing permeation ability through the biological membranes (Qin et al, 2002;Kweon et al, 2003). Classical partition coefficients (p) obtained using n-octanol as the organic solvent show a pH dependency as predicted by the basic nature of Doxepine with a pK a of nine.…”

Section: Lipophylicity Of Doxepinmentioning

confidence: 99%

Design, development and characterization of buccal bioadhesive films of Doxepin for treatment of odontalgia

et al. 2014

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Tricyclic antidepressants, as doxepin hydrochloride (DH), may have analgesic local effect due to its biochemical mechanism of action. Delivery of DH directly to the oral cavity could be an interesting alternative for toothache due to its analgesic local effect. One problem associated with the mucosal administration routes is the short residence time of the dosage form on the mucosal membranes. In this sense, we have developed new doxepin mucoadhesive films able of reducing pain and increasing the effectiveness of treatment. For this purpose, we tested three different polymers: chitosan, sodium hydroxypropylmethylcellulose (HPMC) and sodium carboxymethylcellulose (SCMC) in film elaboration. The results obtained show that all films are hydrophilic matrices that absorb water when placed in an aqueous media. All the films hydrated very quickly, reaching high percentage of swelling after just few minutes (5 min for SCMC, 2 min for HPMC and 30 min for chitosan). Moreover, the SCMC and HPMC films were dissolved whereas chitosan was not dissolved. Dissolution also leads to viscous liquids with a higher retention time over mucosal surfaces what may lead to adhesive interactions. In vitro permeation studies showed that for all the formulations studied, SCMC (19.91%), HPMC (69.5%) and chitosan (24.17%), the percentage of drug permeated increased compared to the drug solution (8.26%). Specifically the HPMC film presents greater amounts of doxepin permeated (49.27 ± 4.47 mg/cm 2 ).

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Enzymic preparation of water-soluble chitosan and their antitumor activity

Cited by 279 publications

References 25 publications

Characterization of chito-oligosaccharides prepared by chitosanolysis with the aid of papain and Pronase, and their bactericidal action against Bacillus cereus and Escherichia coli

Characterization of chito-oligosaccharides prepared by chitosanolysis with the aid of papain and Pronase, and their bactericidal action against Bacillus cereus and Escherichia coli

Effects of Chitosan-oligosaccharide on diarrhoea in Hanwoo calves

Design, development and characterization of buccal bioadhesive films of Doxepin for treatment of odontalgia

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