Abstract
PurposeImprovement in water content and skin barrier function on human skin is believed to be induced by koji amazake, a non-alcoholic beverage derived from rice fermented by Aspergillus oryzae (A. oryzae). In order to scientifically identify the effects of koji amazake on human skin, we performed a randomized, double-blind, placebo-controlled, parallel-group comparative trial and quantified the content of glucosylceramide (GlcCer) which would be responsible for the effects.Participants and MethodsHealthy adults concerned with their skin dryness were divided into koji amazake (N = 30) or placebo group (N = 30). During this test, the test beverages were ingested at 118 g/day. Their water content and trans-epidermal water loss (TEWL) were measured at 0 week (baseline) and 8 weeks. The content of GlcCer in test beverages was quantified by HPLC-ELSD.ResultsIn comparison with the placebo group, the water content in the left cheek of individuals in the koji amazake group was maintained for 8 weeks. In addition, changes in water content from the baseline to 8 weeks differed significantly between the koji amazake (0.19) and placebo groups (−3.98). Unexpectedly, there was no significant difference in the TEWL between koji amazake and placebo group. We analyzed GlcCer in both koji amazake and placebo beverages, which were found to contain 1.35 ± 0.11 and 0.30 ± 0.07 mg/118 g, respectively. The amount of GlcCer in koji amazake was approximately equal to the dosage of plant-derived GlcCer which has the ability to improve water content and TEWL in humans.ConclusionPresent study has shown that intake of koji amazake contributes to maintain the water content only on the left cheek. The content of GlcCer derived from koji amazake was adequate for maintenance of the water content compared to previous reports. Therefore, it was concluded that GlcCer in koji amazake acts as a functional ingredient.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Clinical, Cosmetic and Investigational Dermatology
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
