Fine structure characterization and cosmetic efficacy evaluation of polysaccharides from rose essential oil processing waste.

In this study, rose waste liquid polysaccharides (RPSL) were extracted from rose essential oil processing waste (rose waste liquid) to investigate their fine structure and their cosmetically relevant biological activities. The fraction with the highest in vitro antioxidant capacity, designated RPSL-2, had a molecular weight of 5.06 × 104 Da. Its monosaccharide composition was determined to be Ara:Glc:Gal:Rha:Gal-A:Man:Xyl:Glc-A:Fuc in a molar ratio of 91.60:49.69:41.16:16.00:13.64:4.24:3.18:1.71:1.00, respectively. Methylation and NMR experiments showed that RPSL-2 was mainly composed of →4)-β-D-Galp-(1→, →4)-α-D-Glcp-(1→, →5)-α-L-Araf-(1→, →3,5)-α-L-Araf-(1→, →4)-α-D-GalpA-(1→ and →3,6)-β-D-Glcp-(1→, interconnected to form the main chain. The side-branch chains consisted of α-L-Araf-(1→ attached at the O-3 position of the sugar residue →3,5)-α-L-Araf-(1→, and α-L-Araf-(1→ attached at the position of the sugar residue →3,6)-β-D-Glcp-(1→O-6. Skin-health-related activity evaluation using zebrafish models indicates that RPSL-2 inhibits skin melanin formation by regulating the expression of the dct, oca2, and silv genes, promotes skin tissue growth by regulating the expression of the collagen biosynthesis-related genes, col1a1a and col1a2, and promotes the formation of red blood cells. Therefore, the polysaccharides extracted from rose waste liquid have biological activities potentially applicable in cosmetic applications, such as skin whitening, ameliorating skin wrinkling and blood replenishment.