RESUMEN
This study investigated the impact of ultrasonic extraction (UE) on the structure and inâ vitro antibacterial activity of polysaccharides from sugarcane leaves (SLW). Native sugarcane leaf polysaccharides were treated with ultrasound (480â W) for 3 h to yield sugarcane leaf polysaccharides (SLU). Compared to SLW (33.59â kDa), the molecular weight of SLU (13.08â kDa) was significantly decreased, while the monosaccharide composition of SLU was unchanged. The results of SEM and XRD indicated that UE significantly changed the surface morphology of SLW and destroyed its inner crystalline structure. In vitro experiments showed that SLU had stronger antibacterial activity. These findings revealed that UE treatment could alter the tertiary structure of SLW but had no impact on its primary structure. Furthermore, the antibacterial activity of SLW could be greatly enhanced after UE treatment. As a bioactive additive, SLU has great application potential in functional foods, cosmetics, and pharmaceuticals.