title: Effects of Fab' fragments of specific egg yolk antibody (IgY-Fab') against Shewanella putrefaciens on the preservation of refrigerated turbot.
abstract: BACKGROUND
  In our previous studies the specific egg yolk antibody (IgY) against Shewanella putrefaciens (one of the specific spoilage organisms for marine products during aerobic chilling storage) demonstrated significant activity to prolong the shelf life of refrigerated fish. The exploitation of the antigen-binding fragment plus the hinge region (IgY-Fab') is now considered a promising method for improving the efficiency of such natural antimicrobial agents.
  
  
  RESULTS
  The antimicrobial activity of IgY-Fab' against S. putrefaciens was investigated using refrigerated turbot as samples. By microbial, chemical and sensory tests, it was shown to be able to effectively inhibit bacterial growth and prolong the shelf life of samples, with an efficiency evaluated significantly higher than that of whole IgY with the same molarity. The interaction between IgY agents and S. putrefaciens cells was also investigated, and the IgY-Fab' showed a much greater ability to damage cell membranes than the whole IgY.
  
  
  CONCLUSIONS
  Compared to whole IgY with the same molarity, IgY-Fab' demonstrated higher and more durable antimicrobial efficiency. Such a result was assumed to be closely related to its structural properties (such as the much lower molecular weight), which may enhance its ability to influence physiological activities of antigen bacteria, especially the property or/and structure of cell membranes.
authors.affiliation: Food Safety Laboratory, Ocean University of China, Qingdao, 266003, People's Republic of China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Zhang
authors.forename: Hong
authors.initials: H
authors.lastname: Lin
authors.forename: Jianxin
authors.initials: J
authors.lastname: Sui
authors.forename: Jingxue
authors.initials: J
authors.lastname: Wang
authors.forename: Limin
authors.initials: L
authors.lastname: Cao
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents; D003080:Cold Temperature; D004530:Egg Yolk / Q000276:immunology*; D005412:Flatfishes / Q000382:microbiology*; D005519:Food Preservation / Q000379:methods*; D007140:Immunoglobulin Fab Fragments / Q000276:immunology / Q000494:pharmacology*; D007136:Immunoglobulins / Q000276:immunology / Q000494:pharmacology*; D017747:Seafood / Q000382:microbiology; D020614:Shewanella putrefaciens / Q000187:drug effects* / Q000276:immunology
chemical_list: D000890:Anti-Infective Agents; C016512:IgY; D007140:Immunoglobulin Fab Fragments; D007136:Immunoglobulins
keywords: IgY-Fab′; antimicrobial activity; preservation; refrigerated turbot