antimicrobial action of chitosan, low molar mass chitosan, and chitooligosaccharides on human colonic bacteria

• Published in: Folia microbiologica Vol. 57; no. 4; pp. 341 - 345
• Main Authors: Simnek, Jiri, Brandysova, Vra, Koppova, Ingrid
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer-Verlag 01.07.2012; Springer Netherlands; Springer Nature B.V
• Subjects: anaerobes; Anaerobic bacteria; Anti-Bacterial Agents - chemistry; Anti-Bacterial Agents - pharmacology; antibacterial properties; Antimicrobial activity; Antimicrobial agents; Applied Microbiology; Bacteria; Bacteria - classification; Bacteria - drug effects; Bacteria - genetics; Bacteria - isolation & purification; Bacteriodes; Bacteroides vulgatus; Biomedical and Life Sciences; chitooligosaccharides; chitosan; Chitosan - chemistry; Chitosan - pharmacology; Clostridium; Clostridium beijerinckii; Clostridium paraputrificum; Colon; Colon - microbiology; Dietary supplements; Environmental Engineering/Biotechnology; Faecalibacterium prausnitzii; Growth rate; Humans; Hydrolysates; Immunology; intestinal microorganisms; Life Sciences; Microbial Sensitivity Tests; Microbiology; Microflora; Minimum inhibitory concentration; Molecular Weight; Oligosaccharides - chemistry; Oligosaccharides - pharmacology; Polymerization; Roseburia intestinalis; specific growth rate; Minimum Inhibitory Concentration; GlcN; Specific Growth Rate; Chitosan; Minimal Bactericidal Concentration
• ISSN: 0015-5632; 1874-9356
• DOI: 10.1007/s12223-012-0138-1

Antibacterial effect of chitooligosaccharides (COS) and low molar mass chitosans (LMWC) is considered as one of the most important characteristics of chitosan (CS) hydrolysates. Here, we show the in vitro effect of different COS, LMWC, and CS on representative anaerobic bacteria isolated from human colon as a possibility of targeting modification of colonic microflora composition by supplementation of dietary CS products by humans. Specific growth rate of seven selected nonpathogenic anaerobic bacterial strains (Clostridium paraputrificum, Clostridium beijerinckii, Roseburia intestinalis, Bacteroides vulgatus, Bacteriodes thetaiotaomicron, Faecalibacterium prausnitzii and Blautia coccoides) was determined in the presence of 0.25 and 0.5% COS (2, 3, and 6 kDa), 0.025 and 0.05% of LMWC (10 and 16 kDa), and 0.025 and 0.1% of CS in vitro. The growth rate decreased in all strains in the presence of COS and LMWC in higher concentrations in comparison to control incubations. A relatively higher resistance to CS hydrolyzates was detected in R. intestinalis and F. prausnitzii, and more susceptible were bacteria belonging to Bacteoides sp. and Clostridium sp. The antimicrobial activity, minimum inhibitory concentrations (MIC), and minimal bactericidal concentrations (MBC) were determined. The antimicrobial activity increased with the degree of polymerization (DP). MIC ranged from 0.25 to 4.5% in dependence on bacterial strain and DP of CS/LMWC. MBC also decreased with DP. The most effective antimicrobial action was detected in LMWC with 16 kDa and CS. Weak antimicrobial activity was found in COS with small molecules (2 and 3 kDa).