Structure, selenization modification, and antitumor activity of a glucomannan from Platycodon grandiflorum

Platycodon grandiflorum is consumed popularly as a nutritional and healthy plant in East Asia, which has multiple medicinal functions. As an exploration to elucidate the beneficial ingredients, an acetylated glucomannan (PGP40-1) was purified from P. grandiflorum. Structural analysis showed that PGP40-1 was composed of →4)-β-Manp-(1→, →4)-β-Glcp-(1→, →6)-β-Glcp-(1→, and terminal α-Glcp-(1→. PGP40-1 was found to possess weak antitumor activity in vitro, which was thus modified to afford a selenized polysaccharide (Se-PGP40-1) by the HNO