Study on antibacterial effects of chitosan oligosaccharide and pectin oligosaccharide

NIE Xiaoyu; MEI Yihao; HUANG Chong; WANG Rongyue; LIU Juan

doi:10.13557/j.cnki.issn1002-2813.2025.24.018

Abstract：The experiment aimed to investigate the antibacterial effects and mechanisms of two oligosaccharides on six tested strains.The antibacterial effects of chitosan oligosaccharides(COS)and pectin oligosaccharides(POS)on six test strains were determined by the double dilution method and the Oxford cup method in the experiment,and the antibacterial mechanism was preliminarily expounded by measuring the permeability of cell membranes.The results showed that the two oligosaccharides had inhibitory effects of varying degrees on all six tested strains.The minimum inhibitory concentration(MIC)of COS against Escherichia coli,Bacillus subtilis,Rhodotorula diobovata,Aeromonas hydrophila,Shewanella marisflavi,and Vibrio splendidus were all≤18 g/L,demonstrating significant broad-spectrum inhibitory activity.The MIC of POS against Escherichia coli,Bacillus subtilis,Shewanella marisflavi,and Vibrio splendidus were≤40 g/L,but the inhibitory effect on Rhodotorula diobovata and Aeromonas hydrophila was relatively weak,and the MIC was not detected within the test concentration range.The inhibition zone test further confirmed the above results,and the antibacterial effect increased with the increase of oligosaccharide concentration.The antibacterial mechanisms of both COS and POS were to disrupt the permeability of the bacterial cell membrane,causing the contents to leak out and thereby affecting their metabolic activity and inhibiting bacterial growth.With the increase of oligosaccharide concentration,the activity of alkaline phosphatase and the content of macromolecular substances in the bacterial liquid were increased,and the antibacterial performance was stronger.The study indicates that both oligosaccharides have excellent antibacterial effects and can inhibit bacterial growth by disrupting the permeability of bacterial cell membranes.