title: Photodynamic antimicrobial activity of avian eggshell pigments.
abstract: Pigmentation in avian eggshells appears to be associated with shell strength, temperature regulation, and camouflage. The pigments found in eggshells are mainly porphyrins, which have been utilized therapeutically as photosensitizers. Here, we examined the photoinactivation of gram-positive (Staphylococcus aureus, Bacillus cereus) and gram-negative bacteria (Escherichia coli, Salmonella enteritidis) by hen eggshells and their pigments. The results indicated that eggshells have a light-dependent antimicrobial activity against gram-positive, but not gram-negative, bacteria. Our results indicate the possibility that the natural pigments used therapeutically have evolved in nature as a defence system.
authors.affiliation: Department of Animal Science, School of Veterinary Medicine, Kitasato University, Towada, Aomori, Japan. ishikawa@vmas.kitasato-u.ac.jp
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Ishikawa
authors.forename: Kazuto
authors.initials: K
authors.lastname: Suzuki
authors.forename: Eriko
authors.initials: E
authors.lastname: Fukuda
authors.forename: Keizo
authors.initials: K
authors.lastname: Arihara
authors.forename: Yuji
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Takao
authors.initials: T
authors.lastname: Mukai
authors.forename: Makoto
authors.initials: M
authors.lastname: Itoh
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000494:pharmacology*; D001409:Bacillus cereus / Q000187:drug effects / Q000528:radiation effects; D001664:Biliverdine / Q000494:pharmacology; D002645:Chickens; D004528:Egg Shell / Q000737:chemistry*; D004926:Escherichia coli / Q000187:drug effects / Q000528:radiation effects; D005260:Female; D006090:Gram-Negative Bacteria / Q000187:drug effects / Q000528:radiation effects; D006094:Gram-Positive Bacteria / Q000187:drug effects / Q000528:radiation effects; D008027:Light; D008826:Microbial Sensitivity Tests; D050296:Microbial Viability / Q000187:drug effects / Q000528:radiation effects; D017319:Photosensitizing Agents / Q000494:pharmacology; D011166:Porphyrins / Q000494:pharmacology*; D011524:Protoporphyrins / Q000494:pharmacology; D012477:Salmonella enteritidis / Q000187:drug effects / Q000528:radiation effects; D013211:Staphylococcus aureus / Q000187:drug effects / Q000528:radiation effects
chemical_list: D000890:Anti-Infective Agents; D017319:Photosensitizing Agents; D011166:Porphyrins; D011524:Protoporphyrins; C017803:zinc protoporphyrin; C028025:protoporphyrin IX; D001664:Biliverdine