Structural analysis and evaluation of anti-complement and α-amylase inhibitory properties of heteroxylan extracted from Salvia aegyptiaca L. seeds

In the pursuit of novel bioactive compounds, we employed an ethnobotanical approach to explore the potential of Salvia aegyptiaca L. seeds. Polysaccharides isolated from these seeds named PGSA were subjected to characterize utilizing various techniques such as colorimetric assays, FT-IR spectroscopy, TLC, HPLC, and GC/MS-EI. PGSA exhibited notable content (3.65%), with high total carbohydrate (77.34 ± 0.03%), uronic acid (15.17 ± 0.01%), neutral sugar (63.27 ± 0.33%), proteins (6.93 ± 0.01%), and total phenolic components (11.36 ± 0.01%). Predominantly composed of xylose (93%) with traces of galactose (4%), arabinose (1%), and galacturonic acid (2%). We further explored the effects of PGSA and their partial hydrolysis named PGSA_H on anti-complement and α-amylase inhibitory activities. Notably, PGSA_H displayed enhanced anti-complement activity (46.69%) compared to PGSA (40%) and approached that of heparin (53.33%) at 1 mg.mL⁻¹. Additionally, PGSA_H exhibited significant α-amylase inhibitory potential, with an IC50 of 3.3 mg.mL⁻¹, positioning it between PGSA (5 mg.mL⁻¹) and acarbose (0.3 mg.mL⁻¹). These findings underscore the impact of molecular weight on both biological activities. In conclusion, polysaccharides derived from S. aegyptiaca seeds present promising prospects as novel sources of anti-complement agents and enzyme inhibitors, with potential applications in the food and pharmaceutical industries.