title: The effect of UV-C pasteurization on bacteriostatic properties and immunological proteins of donor human milk.
abstract: BACKGROUND
  Human milk possesses bacteriostatic properties, largely due to the presence of immunological proteins. Heat treatments such as Holder pasteurization reduce the concentration of immunological proteins in human milk and consequently increase the bacterial growth rate. This study investigated the bacterial growth rate and the immunological protein concentration of ultraviolet (UV-C) irradiated, Holder pasteurized and untreated human milk.
  
  
  METHODS
  Samples (n=10) of untreated, Holder pasteurized and UV-C irradiated human milk were inoculated with E. coli and S. aureus and the growth rate over 2 hours incubation time at 37°C was observed. Additionally, the concentration of sIgA, lactoferrin and lysozyme of untreated and treated human milk was analyzed.
  
  
  RESULTS
  The bacterial growth rate of untreated and UV-C irradiated human milk was not significantly different. The bacterial growth rate of Holder pasteurized human milk was double compared to untreated human milk (p<0.001). The retention of sIgA, lactoferrin and lysozyme after UV-C irradiation was 89%, 87%, and 75% respectively, which were higher than Holder treated with 49%, 9%, and 41% respectively.
  
  
  CONCLUSIONS
  UV-C irradiation of human milk preserves significantly higher levels of immunological proteins than Holder pasteurization, resulting in bacteriostatic properties similar to those of untreated human milk.
authors.affiliation: School of Chemistry and Biochemistry, Faculty of Science, The University of Western Australia, Crawley, Western Australia, Australia ; Carag AG, Baar, Switzerland.
authors.forename: Lukas
authors.initials: L
authors.lastname: Christen
authors.affiliation: School of Chemistry and Biochemistry, Faculty of Science, The University of Western Australia, Crawley, Western Australia, Australia.
authors.forename: Ching Tat
authors.initials: CT
authors.lastname: Lai
authors.affiliation: Perron Rotary Express Milk Bank, King Edward Memorial Hospital, Subiaco, Western Australia, Australia ; Centre for Neonatal Research and Education, The University of Western Australia, Crawley, Western Australia, Australia.
authors.forename: Ben
authors.initials: B
authors.lastname: Hartmann
authors.affiliation: School of Chemistry and Biochemistry, Faculty of Science, The University of Western Australia, Crawley, Western Australia, Australia.
authors.forename: Peter E
authors.initials: PE
authors.lastname: Hartmann
authors.affiliation: School of Chemistry and Biochemistry, Faculty of Science, The University of Western Australia, Crawley, Western Australia, Australia.
authors.forename: Donna T
authors.initials: DT
authors.lastname: Geddes
mesh_terms: D000704:Analysis of Variance; D004926:Escherichia coli / Q000254:growth & development / Q000528:radiation effects; D005260:Female; D005514:Food Irradiation / Q000379:methods*; D006801:Humans; D007071:Immunoglobulin A, Secretory / Q000378:metabolism; D007781:Lactoferrin / Q000378:metabolism; D008895:Milk, Human / Q000276:immunology* / Q000382:microbiology* / Q000528:radiation effects*; D009113:Muramidase / Q000378:metabolism; D061352:Pasteurization / Q000379:methods*; D013211:Staphylococcus aureus / Q000254:growth & development / Q000528:radiation effects; D014466:Ultraviolet Rays; D061349:Unrelated Donors
chemical_list: D007071:Immunoglobulin A, Secretory; D009113:Muramidase; D007781:Lactoferrin