Table 4.
Overview of the anti-pathogenic functionalities of COS.
| COS Characteristics + Source | [COS] | Strains Used | Observed Effects | References |
|---|---|---|---|---|
| Chitosan oligosaccharides-from chitosan with DA 89%, DP 3–6 (805) |
0.01–0.5% | Gram-negative: Escherichia coli | Antibacterial activity (anti-growth) and 0.5% completely inhibited the growth of E. coli | [126] |
| Chito-oligosaccharides DA 8.5%, Mw 2–30 kDa |
0.10% |
Gram-negative:
Aggregatibacter actinomycetemcomitans
Gram-positive: Streptococcus mutans |
Pathogenic membrane disruption | [102] |
| Chito-oligosaccharides DA 11% Mw <10, <5, <1 kDa |
0.1–1% |
Gram-negative:Escherichia coli, Salmonella typhimurium, Pseudomonas aeruginosa Gram-positive:Streptococcus mutans, Micrococcus luteus, Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis |
Higher anti-microbial (anti-growth) effect high-Mw COS | [105] |
| Chitosan Mw 5, 8 kDa | 0.01–0.5% | Gram-negative: Escherichia coli | mRNA transcription inhibition | [121] |
| Chitosans (Mw = 1671, 1106, 746, 470, 224, and 28 kDa) Chitosan oligomers (Mw = 22, 10, 7, 4, 2, and 1 kDa) |
1% | Gram-negative: Escherichia coli, Pseudomonas fluorescens, Salmonella typhimurium, Vibrio parahaemolyticus Gram-positive: Listeria monocytogenes, Bacillus megaterium, Bacillus cereus, Staphylococcus aureus | Higher anti-microbial effect (anti-growth) of chitosan compared to COS Chitosan showed stronger bactericidal effects for gram-positive bacteria than gram-negative bacteria |
[93] |
| Chitosan Mw < 5 kDa | 0.25–1% |
Gram-negative:
Escherichia coli
Gram-positive: Staphylococcus aureus |
E. coli growth inhibition (lower Mw more effective) S. aureus growth inhibition (higher Mw more effective) |
[94] |
| Chito-oligosaccharides DA 35.2–37.8% DP 1–6 |
0.1–0.5% |
Gram-negative:
Escherichia coli
Gram-positive: Bacillus cereus |
Growth inhibition and cell membrane disruption | [112] |
| Chito-oligosaccharides DA 3%, DP ~4 |
0.25–2.5% | Gram-negative: VTEC, EPEC, Desulfovibrio desulfuricans | Selective anti-adhesion properties | [116] |
| Chitosan oligosaccharides DA 98.8%, DP 1–16 |
0.0001–0.5% | Gram-positive: Staphylococcus aureus | Cell membrane lysis | [113] |
| Chito-oligosaccharides DA 15–20%, MW <5, <3 kDa |
1–5% |
Gram-negative:
Escherichia coli
Gram-positive: Staphylococcus aureus |
Antimicrobial effect (anti-growth) on Escherichia coli, but not Staphylococcus aureus | [95] |
| Chitosan DA > 90% | 0.0004–6.7% | Gram-negative:Pseudomonas aeruginosa (MDR) | Synergy with sulfamethoxazole treatment (anti-growth effect) | [125] |
| Chitosan oligosaccharides-Mw= 10,000 Da and 1000 Da)-from chitosan with DA 90–95% | 0.5–10 mg/mL | Gram-negative: Vibrio vulnificus | Higher antimicrobial effect (anti-growth) of water-soluble COS with high molecular weight | [127] |
| Chitosan DA >90% | 0.0004–6.7% | Gram-possitive:Staphylococcus aureus (MDR) | Synergy with several AB treatments (anti-growth effect) | [124] |
| Chitosans DA 80–85% Mw = 628, 591 and 107 kDa Chito-oligosaccharides DA 80–85% Mw = <5 and <3 kDa |
0.5% |
Gram-negative:
Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae
Gram-positive: Staphylococcus aureus, Staphylococcus epidermidis |
Higher antimicrobial effect (anti-growth) of the 3 chitosans | [104] |
| Chitin (DA 35, Mw 388 Da) Chitosan (DA 80, Mw 12 Da) COS |
0.003–0.1% |
Gram-negative:
Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium, Vibrio cholerae, Shigella dysenteriae, Enterobacter agglomerans, Prevotella melaninogenica, Bacteroides fragilis
Gram-positive: Staphylococcus aureus, Bacillus subtilis, Bacillus cereus |
Higher antimicrobial effect (anti-growth) COS compared to biopolymers | [114] |
| Chito-oligosaccharides DA ~65%, DP 3–5 |
2% | Gram-negative: Pseudomonas aeruginosa | Anti-growth, anti-biofilm functionalities and synergy with azithromycin | [88] |
| Chito-oligosaccharides DA 9–14%, DP <5–30 | 1–10% |
Gram-negative:
Escherichia coli
Gram-positive: Listeria monocytogenes |
High antimicrobial effect (anti-growth) with high DP | [103] |
| Chito-oligosaccharides-from chitosan with DD 80 and 90%-from chitosan with Mw = 5.1, 14.3 and 41.1 kDa | 0.002–0.064% | Gram-negative: Escherichia coli, Salmonella typhimurium, Salmonella enteritidis | High antimicrobial effect (anti-growth) with low DP, potent ferrous chelating activity at low DP | [128] |