A novel method to control the balance of skin microflora. Part 1. Attack on biofilm of Staphylococcus aureus without antibiotics.
BACKGROUND
Staphylococcus aureus (SA) is usually present in atopic dry skin, and not only in regions seriously affected by atopic dermatitis. SA discharges various toxins and enzymes that injure the skin, and forms a biofilm from fibrin fiber and glycocalyx; the biofilm is important for adhesion of SA to the skin and for resistance to anti-microbial agents. Even highly effective moisturizers do not work perfectly on atopic dry skin. Staphylococcus epidermidis (SE) is a major constituent of skin microflora on healthy human skin, and provides protection against the growth of pathogenic bacteria.


OBJECTIVE
Since treatment with anti-microbials may lead to re-growth of SA, which grows faster than other Staphylococci and often shows antibiotic resistance, we searched for novel approaches to control the skin-microfloral balance without using conventional anti-microbials.


METHODS
Biofilm formation by SA in vitro was observed in detail using scanning electron microscopy. Approximately 500 substances were screened for a selective effect on SA growth and SA biofilm.


RESULTS
We found that xylitol inhibited the formation of glycocalyx, and farnesol dissolved fibrin fibers. Farnesol suppressed the growth of only SA, and did not affect that of SE. Xylitol and farnesol synergistically inhibited biofilm formation by SA.


CONCLUSIONS
Xylitol and farnesol have potential for controlling the skin-microfloral balance because of their selective effects and inhibition of biofilm formation. They might provide a useful and safe method to care for skin colonized by SA, without using antibiotics.
Katsuyama
Masako
M
Life Science Research Center, Shiseido Co. Ltd., Tsuzuki-ku, Yokohama, Japan. masako.katsuyama@to.shiseido.co.jp
Masako
Katsuyama
K
Ichikawa
Hideyuki
H
Hideyuki
Ichikawa
I
Ogawa
Shigeyuki
S
Shigeyuki
Ogawa
O
Ikezawa
Zenro
Z
Zenro
Ikezawa
I
D000279:Administration, Cutaneous; D001422:Bacterial Adhesion; D018441:Biofilms / Q000187:drug effects / Q000254:growth & development*; D015169:Colony Count, Microbial; D003876:Dermatitis, Atopic / Q000188:drug therapy / Q000382:microbiology; D003879:Dermatologic Agents / Q000008:administration & dosage; D005204:Farnesol / Q000008:administration & dosage / Q000494:pharmacology; D005260:Female; D006801:Humans; D008297:Male; D008855:Microscopy, Electron, Scanning; D012867:Skin / Q000187:drug effects / Q000382:microbiology*; D013211:Staphylococcus aureus / Q000187:drug effects / Q000472:pathogenicity* / Q000502:physiology* / Q000648:ultrastructure; D013212:Staphylococcus epidermidis / Q000187:drug effects / Q000502:physiology; D014993:Xylitol / Q000008:administration & dosage / Q000494:pharmacology
D003879:Dermatologic Agents; D005204:Farnesol; D014993:Xylitol