Although our previous research has indicated that the ultrasound-assisted extraction–deep eutectic solvent method possessed the highest extraction yield for Polygonatum sibiricum Polysaccharide, it is uncertain whether the Polygonatum sibiricum Polysaccharide that was extracted by the ultrasound-assisted extraction–deep eutectic solvent method possesses the same performance as that extracted by other methods and whether separation and purification affect the performance of Polygonatum sibiricum Polysaccharide. This paper aimed to compare the differences in performance among the Polygonatum sibiricum Polysaccharides extracted using different methods, including the ultrasound-assisted extraction–deep eutectic solvent method, which was the first method used by our team to extract Polygonatum sibiricum Polysaccharide. This paper also aimed to compare the differences in Polygonatum sibiricum Polysaccharides before and after they were separated and purified. The extraction yield, structural composition, and antioxidant activity of Polygonatum sibiricum Polysaccharides were compared, respectively. The extraction yield (45.08%) obtained by the ultrasound-assisted extraction–deep eutectic solvent method was the highest (p < 0.05), the structural compositions of Polygonatum sibiricum Polysaccharides extracted using different methods were similar, and the separated and purified Polygonatum sibiricum Polysaccharide was a neutral polysaccharide. The 2,2–diphenyl–1–picrylhydrazyl and 2,20–azino–bis (3–ethylbenzothiazoline–6–sulfoniacid) levels in the Polygonatum sibiricum Polysaccharide extracted by the ultrasound-assisted extraction–deep eutectic solvent method were significantly higher than those obtained using other methods (p < 0.05), and the antioxidant activity of the Polygonatum sibiricum Polysaccharide extracted by this method was significantly higher after it was separated and purified (p < 0.05). This study not only proved that the ultrasound-assisted extraction–deep eutectic solvent method could increase the extraction yield and keep the structural composition and antioxidant activity of Polygonatum sibiricum Polysaccharide at the maximum levels but also confirmed that the extracted Polygonatum sibiricum Polysaccharide should not be further separated and purified, providing a potential technique to extract Polygonatum sibiricum Polysaccharide. This study will further promote the application of Polygonatum sibiricum Polysaccharides in the health product industry.

The main active component of Polygonatum sibiricum (P. sibiricum) rhizome is Polygonatum sibiricum Polysaccharide (PsP) with antioxidant function. At present, only the mature rhizome of P. sibiricum is used to extract PsP, while the young rhizome of by-product is discarded directly as waste, resulting in significant wastage of P. sibiricum resources. We used ultrasound-assisted extraction-deep eutectic solvents (UAE-DESs) method to extract PsP of young and mature rhizomes, respectively. The extraction rate, structure composition and antioxidant ability of PsP between young and mature rhizomes were compared, so as to provide references for comprehensive utilization of P. sibiricum resources. The PsP extraction rate (33.88 ± 1.95%) of young rhizome was close to that (45.08 ± 1.92%) of mature rhizomes. The main component (PsP-2) of the PsP in young rhizome contained six kinds of monosaccharides, which belonged to acidic polysaccharides. The above characteristics of the PsP of young rhizome were similar to those of mature rhizome. The PsP of young rhizome also exhibited similar biological activity to that of the mature rhizome, which indicated even more advantages in DPPH free radical scavenging ability. The results of this study support the utility of the young rhizome, consequently helping to avoid unnecessary waste and provide reference for comprehensive utilization of P. sibiricum.

Oxidative stress is closely associated with sarcopenia obesity (SO). As the primary active component of Polygonatum sibiricum, Polygonatum sibiricum polysaccharide (PsP) is recognized as a potent antioxidant and has become a focus of research for potential therapeutic strategies against SO. Our previous study demonstrated that ultrasound-assisted deep eutectic solvents (UAE-DESs) significantly improve the extraction efficiency of PsP; however, the antioxidant effect of PsP extracted using UAE-DESs was unexplored. This study investigated the effects of PsP extracted by UAE-DESs on an oxidative stress model in L6 cells induced by palmitic acid (PA). The results revealed that PsP enhanced the ability of L6 cells to resist PA-induced effects, including ectopic lipid deposition, changes in reactive oxygen species (ROS) levels, malondialdehyde (MDA) contents, and the activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and catalase (CAT). Additionally, PsP upregulated the expression of myosin heavy chain (MHC) and myoblast differentiation (MyoD) protein, while increasing myotube cell diameter. These findings suggested that PsP extracted by UAE-DESs can enhance the antioxidant capacity of L6 cells against PA-induced oxidative stress in a simulated SO model, providing a potential therapeutic agent for the prevention and treatment of SO.