This study aimed at investigating gastroprotective activity of Hericium erinaceus polysaccharide (HEP) and characterizing one of its bioactive fractions. Acetic acid-induced gastric ulcer (GU) rat model was used to evaluate the gastroprotective activity of HEP, while H2O2-induced injury GES-1 cell model was conducted to screen the bioactive fractions from HEP. Moreover, one of the bioactive fractions was characterized using methylation and 1D/2D NMR analysis. Results indicated HEP treatment could ameliorate acetic acid-induced GU in rats. HEP supplement decreased levels of interleukin-6, tumor necrosis factor-α and malondialdehyde and myeloperoxidase activity, and increased releases of nitric oxide, prostaglandin E2, epidermal growth factor, vascular endothelial growth factor and basic fibroblast growth factor and superoxide dismutase activity in gastric tissues of ulcerated rats. Five purified polysaccharides from HEP were screened to be bioactive fractions with cytoprotection on H2O2-induced injury in GES-1 cells. Among them, RP-S was characterized to be a (1→6)-β-D-glucan, whose backbone was composed of →6)-β-D-Glcp-(1 → residue and branched with T-β-D-Glcp-(1 → residue at O-3 position. In conclusion, HEP possessed gastroprotection against acetic acid-induced GU in rats and one of its bioactive fractions was a β-D-glucan. This study supports the utilization of HEP in anti-GU and provides evidences for the structure of gastroprotective HEP.

polysaccharide, glucan, Hericium erinaceus, bioactive fraction, gastroprotective activity

13C NMR data:
Linkage	Residue	C1	C2	C3	C4	C5	C6
6,6,6	bDGlcp	102.92	72.95	75.47	69.51	74.84	68.71
6,6,3	bDGlcp	102.81	73.04	75.82	69.48	74.69	60.61
6,6	bDGlcp	102.92	72.79	84.11	69.49	74.78	68.50
6	bDGlcp
	bDGlcp	102.92	72.95	75.47	69.51	74.84	68.71


1H NMR data:
Linkage	Residue	H1	H2	H3	H4	H5	H6
6,6,6	bDGlcp	4.51	3.30	3.44	3.71	3.60	3.83-4.18
6,6,3	bDGlcp	4.49	3.27	3.47	3.43	3.62	3.71-3.88
6,6	bDGlcp	4.49	3.52	3.75	3.53	3.65	3.86-4.20
6	bDGlcp
	bDGlcp	4.51	3.30	3.44	3.71	3.60	3.83-4.18


1H/13C HSQC data:
Linkage	Residue	C1/H1	C2/H2	C3/H3	C4/H4	C5/H5	C6/H6
6,6,6	bDGlcp	102.92/4.51	72.95/3.30	75.47/3.44	69.51/3.71	74.84/3.60	68.71/3.83-4.18
6,6,3	bDGlcp	102.81/4.49	73.04/3.27	75.82/3.47	69.48/3.43	74.69/3.62	60.61/3.71-3.88
6,6	bDGlcp	102.92/4.49	72.79/3.52	84.11/3.75	69.49/3.53	74.78/3.65	68.50/3.86-4.20
6	bDGlcp
	bDGlcp	102.92/4.51	72.95/3.30	75.47/3.44	69.51/3.71	74.84/3.60	68.71/3.83-4.18

There is only one chemically distinct structure:

SVGMWSMILES3D molIonize

 

[*]OC[C@H]1O[C@@H](OC[C@H]2O[C@@H](OC[C@H]3O[C@@H](OC[C@H]4O[C@@H]([*])[C@H](O)[C@@H](O)[C@@H]4O)[C@H](O)[C@@H](O)[C@@H]3O)[C@H](O)[C@@H](O[C@@H]3O[C@H](CO)[C@@H](O)[C@H](O)[C@H]3O)[C@@H]2O)[C@H](O)[C@@H](O)[C@@H]1O

810.705 g/mol (C₃₀H₅₀R₂O₂₅, R = next and previous repeats, not counted in mol weight)