Purification, characterization, and in vitro antitumor activity of a novel glucan from the purple sweet potato Ipomoea Batatas (L.) Lam

A novel glucan PSPP-1 (18.3 kDa) was purified from the foot tuber of purple sweet potato Ipomoea Batatas (L.) Lam. Its backbone was composed of -> 4)-alpha-D-Glcp(1 -> glycosyl, and branching at the O-2, O-3, and O-6 positions with alpha-D-Glcp(1 -> residues. X-ray diffraction experiment showed that PSPP-1 existed as an amorphous form. Its microstructure was detected via scanning electron microscopy. Its particle size was mainly concentrated at 230 nm in water. Congo red and circular dichroism experiments showed there was no triple-helix conformation. Atomic force microscopy data suggested that its height and width ranged from 1.0 to 6.1 nm and 65 to 210 nm, respectively; its maximum ring diameter and chain length was-800 nm and-7.0 mu m, respectively. Furthermore, it exhibited inhibitory activities on HepG2, LOVO, and MCF-7 cells. Collectively, our data are useful for understanding the structural characteristics of sweet potato polysaccharides, and their application in foods and pharmaceutical areas.

Automated summary

A novel glucan PSPP-1 was purified from the foot tuber of purple sweet potato, with a backbone composed of alpha-D-Glcp residues and branching at different positions with alpha-D-Glcp residues. Various experiments revealed its amorphous form, microstructure, particle size, and inhibitory activities on different cells. The findings contribute to understanding the structural characteristics and potential applications of sweet potato polysaccharides.