Structure and Bioactivity of Purified Polysaccharides of Cassia occidentalis Linn. from Different Geographical Origins

As the area of origin may influence the polysaccharide properties of plants, we aimed to comprehensively compare composition of polysaccharides from Cassia occidentalis Linn. (a “famine food”) grown in different regions in China. We collected Cassia occidentalis Linn. specimens form Yunnan and Shandong and investigated previously unreported structural and functional differences among their purified fractions. Crude polysaccharide yields obtained from C. occidentalis from Yunnan (11.07 ± 1.09%) and Shandong (3.15 ± 0.45%) were significantly different (P < 0.05). No compositional differences were observed between the ration of purified fractions obtained via an ion exchange column, indicating that the polysaccharides obtained from both regions were similar in composition. However, Fourier-transform infrared spectroscopy, High-performance liquid chromatography, Nuclear magnetic resonance spectroscopy, and atomic force microscope images revealed several structural differences between the purified polysaccharides obtained from Yunnan and Shandong. Evaluation of antioxidant abilities using the radical scavenging method and the H2O2-induced cell oxidative damage model also revealed structural differences. The study illustrated that the effects exerted by environmental abiotic factors on the composition of these plants.