The changes of integral hair lipid induced by UV irradiation on three ethnic hairs

Abstract

[영문]Purpose: The goal of this project is to investigate lipid changes after UV irradiation in three ethnic hairs.Materials/Methods: We studied UV irradiation induced hair damage in hairs of three ethnic groups. UV irradiation has been performed with self-manufactured phototherapy system. Damaged hair samples were prepared at 12 and 48 hours after UVA and UVB irradiation. We evaluated the changes of hair lipid using SEM, TEM, lipid TEM and HP-TLC.Results: After UV irradiation, hair surface damage was shown. African hair showed more severe damage on hair surface. The lipid composition of three normal ethnic hairs were similar, but Asian hair had more integral hair lipid than other ethnic hairs as a whole. Especially, free fatty acid contents were higher than other lipids. After UV irradiation, lipid contents were decreased. These patterns were shown in all three ethnic hairs. Conclusion: Asian hair has more integral hair lipid than other ethnic hairs. After the UV irradiation, African and Caucasian hair has more damage because they have less integral hair lipid. However, Asian hair has less damage. Therefore we conclude that integral hair lipid may protect the hair against the UV light.