Comparative Study of the Structural Characteristics and Bioactivity of Polysaccharides Extracted from Aspidopterys obcordata Hemsl. Using Different Solvents.

The polysaccharides extracted from Aspidopterys obcordata are thought to have anti-urolithiasis activity in Drosophila kidney stones. This study aimed to assess the effects of different extraction solvents on the yield, chemical composition, and bioactivity of polysaccharides from A. obcordata. A. obcordata polysaccharides were extracted by using four solutions: hot water, HCl solution, NaOH solution, and 0.1 M NaCl. The results revealed that the extraction solvents significantly influenced the extraction yields, molecular weight distribution, monosaccharide compositions, preliminary structural characteristics, and microstructures of polysaccharides. The NaOH solution's extraction yield was significantly higher than the other extraction methods. Vitro antioxidant activity assays revealed that the NaOH solution extracted exhibited superior scavenging abilities towards DPPH and ABTS radicals and higher FRAP values than other polysaccharides. The vitro assays conducted for calcium oxalate crystallization demonstrated that four polysaccharides exhibited inhibitory effects on the nucleation and aggregation of calcium oxalate crystals, impeded calcium oxalate monohydrate growth, and induced calcium oxalate dihydrate formation. The NaOH solution extracted exhibited the most pronounced inhibition of calcium oxalate crystal nucleation, while the hot water extracted demonstrated the most significant suppression of calcium oxalate crystal aggregation. Therefore, it can be inferred that polysaccharides extracted with NaOH solution exhibited significant potential as a viable approach for extracting polysaccharides from stems due to their superior yield and the remarkable bioactivity of the resulting products.

Cyclorhizapuana (Apiaceae), a new species from Sichuan, China.

A new species, Cyclorhizapuana J. Zhou & Z.W. Liu (Apiaceae) from Sichuan Province of China, is described and illustrated here. Morphological comparisons with congeneric species revealed that it is distinguished by its slender habit, sparse annular scars, 4-pinnatisect leaf blade with ultimate segments linear (2-4×0.5-1 mm), subequal rays, oblong fruits with slightly thickened ribs, obconic stylopodium and slightly concave seed face. A molecular analysis based on nuclear ribosomal DNA internal transcribed spacer (ITS) sequences indicated that C.puana is genetically distinct from the other two species of the genus. A distribution map, as well as an updated key, are provided for the species of Cyclorhiza.