Antibacterial activity of shrimp chitosan against Escherichia coli, Salmonella, and Pseudomonas aeruginosa isolated from seafoods
Antibacterial activity of shrimp chitosan against Escherichia coli, Salmonella, and Pseudomonas aeruginosa isolated from seafoods
Date
2006
Authors
Kumar, R.
Surendran, P.K.
Thankappan, T.K.
Journal Title
Journal ISSN
Volume Title
Publisher
Society of Fisheries Technologists(India), Cochin
Abstract
Antibacterial activity of shrimp shell based chitosan was determined against three food borne pathogens viz., Escherichia coli, Salmonella, and Pseudomonas aeruginosa isolated from seafoods. Tests were carried out in phosphate buffered saline (PBS) at pH 6.0. Four different concentrations, 0.01%, 0.03%, 0.05% and 0.1% (w/v) of chitosan were used against E.coli and Salmonella, and 0.01%, 0.05%, 0.5% and 1% were against P.aeruginosa. Chitosan showed stronger bactericidal activity against Salmonella compared to E.coli and P.aeruginosa as evidenced by 3 log cfu.ml super(-1) reduction in Salmonella count with 0.01% chitosan concentration. There was complete elimination of 5 log cfu.ml super(-1) cell count of Salmonella within 24 h at 0.1% chitosan level. There was 3 log reduction in E.coli count at 0.01% chitosan, but not completely inhibited even at the maximum used concentration (0.1%). The inhibition concentration against P.aeruginosa was higher level compared to Enterobacteriaceae and it was found that reduction in 5 log cfu.ml super(-1) was achieved only at 72 h of chitosan exposure. Different chitosan concentrations 0.05%, 0.1% and 1% had almost same inhibition pattern for P.aeruginosa at 6h. 18h 36h and 72h of exposure. The effectiveness of chitosan against tested pathogens showed Salmonella was most susceptible towards chitosan followed by E.coli and P.aeruginosa.
Description
Keywords
antibacterial activity, chitosan, shrimp, salmonella, E.coli, seafoods
Citation
Fishery Technology 2006:43(1), 79-84