Extraction, selenylation modification and antitumor activity of the glucan from Castanea mollissima Blume

The present study aimed to characterize the glucan from C. mollissima Blume fruits and its selenium derivative, then investigate their antitumor activity in vitro. A glucan, designated as CPA, was firstly isolated from the fruits of C. mollissima Blume. Structure analysis indicated that CPA was a linear 1,6-alpha-D-glucan with the average molecular weight about 2.0 x 10(3) kDa. The selenylation modification derivative of CPA (sCPA), exhibited a stronger antiproliferative effect on tumor cells than CPA in vitro. CPA and sCPA could induce HeLa cells apoptosis and decrease mitochondrial membrane potential. sCPA could also arrest HeLa cells in S phase, promote reactive oxygen species generation and activate caspase-3 activity in HeLa cells. These results manifest that CPA and sCPA inhibit the proliferation of HeLa cells via different mechanisms, which is meaningful for their potential use as antitumor drugs.