Poly-γ-Glutamic Acid from a Novel Bacillus subtilis Strain: Strengthening Skin Barrier and Improving Moisture Retention in Keratinocytes and a Reconstructed Skin Model

Authors:
Preprint
Publisher website
Google Scholar
Abstract
A novel Bacillus subtilis HB-31 strain was isolated from Gotjawal Wetland in Jeju Island, Republic of Korea. A mucus substance produced by this strain was identified as high-molecular weight poly-γ-glutamic acid (γ-PGA) using NMR, Fourier transform infrared spectroscopy, and size-exclusion chromatography/multi-angle light scattering analyses. We evaluated whether γ-PGA improved the skin barrier using keratinocytes and reconstructed skin models. In keratinocytes, γ-PGA treatment increased mRNA expression of skin barrier markers, including filaggrin, involucrin, loricrin, serine palmitoyl transferase, fatty acid synthase, and 3-hydroxy-3-methylglutaryl coenzyme A reductase, dose-dependently. γ-PGA also enhanced hyaluronic acid synthesis by upregulating hyaluronic acid synthase-1,-2,and -3 mRNA levels and promoted aquaporin 3 expression, involved in skin hydration. In reconstructed skin models, 1% γ-PGA topical application elevated filaggrin, involucrin, CD44, and aquaporin 3 expression compared to the control. These results suggest that the newly isolated HB-31 can be used as a commercial production system of high-molecular weight γ-PGA, which can be an effective in-gredient for improving skin barrier and moisture. Further research is needed to explore the long-term effects of γ-PGA on skin health and its application in treating skin disorders.

This publication has 44 references indexed in Scilit: