Structure of a highly branched galacturonoglucan from fruits of Schisandra chinensis (Turcz.) Baill.

A novel galacturonoglucan, named SCP-1, is isolated and purified from Schisandra chinensis fruits. The structure of SCP-1 is systematically investigated by a combination of monosaccharide compositions, absolute M-w, methylation analysis, partial acid hydrolysis, isoamylase degradations, and nuclear magnetic resonance spectroscopy. The structure of SCP-1 is theoretically described as follows: (i) Glc and GalA in a molar ratio of 17:3; (ii). 4)-alpha-Glcp-(1 ->.-> 4,6)-alpha-Glcp-(1 ->,-> 3,4,6)-alpha-Glcp-(1 ->, alpha-Glcp-(1 ->,-> 4)-alpha-GalAp-6-OMe-(1 ->, alpha-GalAp-6-OMe-(1 ->, beta-Glcp-(1 ->,-> 6-)-ss-Glcp-(1 -> and -> 3,4)-ss-Glcp-(1 -> in a molar ratio of 48:5:3:3:10:5:12:5:9; (iii) a repeating unit of -> 4)-alpha-Glcp-(1 -> as a backbone with branched points at C-3 and C-6, substituted by different types of acidic and neutral side chains to form multiple branches; and (iv) a rigid rod configuration deduced from alpha value of 1.26 in Mark-Houwink equation ([eta] = kM(alpha)). Anti-tumor assay investigated the effects of SCP-1 on human HepG2 cancer cell lines in vitro. This is for the first time to report a galacturonoglucan in S. chinensis fruits.

Automated summary

A novel galacturonoglucan, SCP-1, is isolated and characterized from Schisandra chinensis fruits. The structure of SCP-1 is systematically investigated using various analytical techniques and is described as a complex repeating unit with specific monosaccharide compositions and branching points. In vitro anti-tumor assays demonstrate the potential of SCP-1 in inhibiting human HepG2 cancer cell growth.