Performance of Platycladus orientalis Leaves Yeast Fermented Solution on Human Dermal Papilla Cells

Platycladus orientalis exhibits significant potential as an antioxidant, anti-inflammatory, and hair growth-promoting ingredient, while the low bioavailability of raw Platycladus orientalis leaves extracts limits their further application. In this study, yeast fermentation was employed to prepare Platycladus orientalis Leaves Yeast Fermented Solution (PYFS). Its performance on human dermal papilla cells (HDPCs) was systematically investigated. The optimal fermentation strain was screened using the methyl thiazolyl tetrazolium (MTT) assay, and Saccharomycopsis fibuligera RTNY119002 (SF) was identified as the most suitable strain for fermentation. The effects of PYFS on the cell cycle distribution, growth factors, inflammatory factors of HDPCs, as well as its hair growth-promoting mechanism, were investigated. Experiments revealed that after fermentation, the proportion of cells in the G0/G1 phase decreased by 11.09%, while the proportion of cells in the S phase increased by 35.44%. Additionally, the level of the growth factor VEGF increased by 42.34%, while the level of the inflammatory factor TGF-β1 decreased by 23.81%. Moreover, the fermentation process correlates with altered mRNA expression of Wnt/β-catenin pathway-related genes by upregulating the mRNA expression levels of β-catenin, DVL1, and LEF1, and downregulating the mRNA expression level of DKK-1. Finally, non-targeted metabolomics technology was used to analyze the metabolite changes after fermentation. The most significant differential metabolites mainly include flavonoids, amino acids and their derivatives, and organic acids and their derivatives. This study utilized microbial fermentation technology to prepare the yeast fermentation solution, selected the optimal fermentation strain, and demonstrated that its fermentation product significantly promotes HDPC metabolic activity, supports hair follicle health by regulating the balance of growth factors, alters expression patterns of Wnt/β-catenin pathway-related genes, and substantially alters the metabolite composition of Platycladus orientalis leaves extract through fermentation.