A neutral heteropolysaccharide (PCIPS2) was isolated and purified from mycelium of Paecilomyces cicadae, which was investigated to be mainly composed of D-mannose, L-rhamnose, 3-O-methyl-D-galactose, D-glucose and D-galactose with a molar ratio of 47.9:3.1:6.4:0.9:0.8. It had a backbone of 1,4-linked α-L-Rhap residues and 1,6-linked α-D-Manp residues with branches at O-3 of α-D-Manp residues. Its side chain was comprised of minor terminal β-D-glucose and 1,4-linked α-3-O-Me-D-Galp residues terminated by α-D-galactose. Furthermore, its chain information on the values of weight-average molar mass (Mw), root mean square radius ([Formula: see text]), hydrodynamic radius (Rh) and intrinsic viscosity ([η]) for PCIPS2 were analyzed to be 3.09 × 10(4)g/mol, 7.8 nm, 3.6 nm and 8.5 mL/g, respectively. The structural exponent α of 0.57 indicated that PCIPS2 existed as a flexible chain conformation with a coil-like structure in 0.1M NaNO3 at 25 °C. In terms of known theory for worm-like chains, the model parameters for PCIPS2 were as following: molar mass per unit contour length (ML) = 379 nm(-1), persistence length (q) = 0.74 nm and hydrodynamic diameter of cylinder (d) = 0.82 nm, which were further evidenced by atomic force microscopy (AFM).

heteropolysaccharide, AFM, Structural characterization, Chain conformation, Paecilomyces cicadae

There is only one chemically distinct structure:

SVGMWSMILES3D molIonize

 

Warning = sub-repeat ending at aDManp: large unit count (45) was reduced to 5
CO[C@H]1[C@@H](O[C@H]2O[C@H](CO)[C@H](O[C@H]3O[C@H](CO)[C@H](O[C@H]4O[C@H](CO)[C@H](O[C@H]5O[C@H](CO)[C@H](O[C@H]6O[C@H](CO)[C@H](O[C@H]7O[C@H](CO)[C@H](O)[C@H](O)[C@H]7O)[C@H](OC)[C@H]6O)[C@H](OC)[C@H]5O)[C@H](OC)[C@H]4O)[C@H](OC)[C@H]3O)[C@H](OC)[C@H]2O)[C@@H](CO)O[C@H](O[C@@H]2[C@H](O)[C@@H](OC[C@H]3O[C@H](OC[C@H]4O[C@H](OC[C@H]5O[C@H](OC[C@H]6O[C@H](OC[C@H]7O[C@H](OC[C@H]8O[C@H](O)[C@@H](O)[C@@H](O)[C@@H]8O)[C@@H](O)[C@@H](O)[C@@H]7O)[C@@H](O)[C@@H](O)[C@@H]6O)[C@@H](O)[C@@H](O)[C@@H]5O)[C@@H](O)[C@@H](O)[C@@H]4O)[C@@H](O)[C@@H](O)[C@@H]3O)O[C@H](CO[C@H]3O[C@H](CO[C@@H]4O[C@@H](C)[C@H](O[C@@H]5O[C@@H](C)[C@H](O[C@@H]6O[C@@H](C)[C@H](O)[C@@H](O)[C@H]6O)[C@@H](O)[C@H]5O)[C@@H](O)[C@H]4O)[C@@H](O)[C@H](O[C@@H]4O[C@H](CO)[C@@H](O)[C@H](O)[C@H]4O)[C@@H]3O)[C@H]2O)[C@@H]1O

3134.859 g/mol (C₁₂₀H₂₀₄O₉₃)

Sanghuang is a well-known edible and medicinal fungus consumed in Asia for centuries. In the present study, a novel exopolysaccharide named as mannan (SSEPS2) was isolated from the liquid culture broth of Sanghuangporus sanghuang by using ethanol precipitation, anion-exchange chromatography, and size-exclusion chromatography, which was exclusively composed of D-mannose with the molecular weight 94300 g/mol. The structural analysis suggested that SSEPS2 consisted of 1,3-linked and 1,2-linked α-D-mannopyranose (Manp), with substitution at O-6 of 1,2-linked α-D-Manp by 1,6-linked α-D-Manp residues and terminal α-D-Manp residues. The exponent of α (0.58) indicated that SSEPS2 existed in a flexible chain conformation, with a coil-like structure in 0.1 M NaNO3 at 25 °C, which was further confirmed by the atomic force microscopy images and a three-dimensional molecular model. It exhibited potential antitumor activity against the growth of HepG2 (human hepatoma) and MCF-7 cell lines in vitro. The IC50 values for inhibiting HepG-2 cells and MCF-7 cells proliferation were 365 and 340 μg/mL, which showed its potential application in the development of anticancer therapeutics.

conformation, mannan, Sanghuangporus sanghuang

13C NMR data:
Linkage	Residue	C1	C2	C3	C4	C5	C6
3,2,2	aDManp	103.35-103.47	70.84	79.23-79.80	67.44-67.75	72.45-74.56	62.41
3,2,6,6	aDManp	103.35	71.23	71.83	68.22	74.47	62.41
3,2,6	aDManp	103.26	71.34	71.83	68.22	72.45	66.87
3,2	aDManp	99.49	79.99	71.52	68.21	72.45	66.87
3	aDManp	101.77	79.50	71.52	68.22	74.56	62.41
	aDManp	103.35-103.47	70.84	79.23-79.80	67.44-67.75	72.45-74.56	62.41


1H NMR data:
Linkage	Residue	H1	H2	H3	H4	H5	H6
3,2,2	aDManp	4.95-5.03	4.13-4.14	3.82-3.86	3.69-3.73	3.69	3.65-3.80
3,2,6,6	aDManp	4.96	3.97	3.74	3.55	3.70	3.65-3.80
3,2,6	aDManp	5.05	3.96	3.74	3.60	3.67	3.74-3.93
3,2	aDManp	5.00	3.94	3.80	3.62	3.67	3.74-3.93
3	aDManp	5.20	4.02	3.81	3.57	3.74	3.65-3.80
	aDManp	4.95-5.03	4.13-4.14	3.82-3.86	3.69-3.73	3.69	3.65-3.80


1H/13C HSQC data:
Linkage	Residue	C1/H1	C2/H2	C3/H3	C4/H4	C5/H5	C6/H6
3,2,2	aDManp	103.35-103.47/4.95-5.03	70.84/4.13-4.14	79.23-79.80/3.82-3.86	67.44-67.75/3.69-3.73	72.45-74.56/3.69	62.41/3.65-3.80
3,2,6,6	aDManp	103.35/4.96	71.23/3.97	71.83/3.74	68.22/3.55	74.47/3.70	62.41/3.65-3.80
3,2,6	aDManp	103.26/5.05	71.34/3.96	71.83/3.74	68.22/3.60	72.45/3.67	66.87/3.74-3.93
3,2	aDManp	99.49/5.00	79.99/3.94	71.52/3.80	68.21/3.62	72.45/3.67	66.87/3.74-3.93
3	aDManp	101.77/5.20	79.50/4.02	71.52/3.81	68.22/3.57	74.56/3.74	62.41/3.65-3.80
	aDManp	103.35-103.47/4.95-5.03	70.84/4.13-4.14	79.23-79.80/3.82-3.86	67.44-67.75/3.69-3.73	72.45-74.56/3.69	62.41/3.65-3.80

There is only one chemically distinct structure:

SVGMWSMILES3D molIonize

 

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

972.846 g/mol (C₃₆H₆₀R₂O₃₀, R = next and previous repeats, not counted in mol weight)

A neutral polysaccharide (SSIPS1) was isolated and purified from cultured mycelia of Sanghuangporus sanghuang by DEAE Sepharose Fast Flow and Sephacryl S-100 columns. Basic monosaccharide composition indicated that SSIPS1 was mainly composed of D-glucose. The results of methylation and 2D-NMR analysis suggested that the glycosidic linkages of SSIPS1 were elucidated to consisted of 1,4-linked α-D-glucopyranose (Glcp) residues with two branched points at O-6. The two branches were composed of 1,4-linked α-D-Glcp terminated with α-D-Glcp, 1,4-linked α-D-Glcp and 1,4-linked β-Galp terminated by α-D-Glcp. Moreover, its chain conformation was revealed to present a flexible chain conformation in 0.1 NaNO3 with a hydrodynamic radius and radius of gyration of 3.26 and 6.45 nm by multi-angle laser light scattering, with a single chain of 0.559 nm observed by atomic force microscopy. Further, SSIPS1 exhibited a potential inhibitory activity against α-amylase and α-glucosidase, and it had hypoglycemic effects on in vitro insulin resistance of HepG2 cells as well.

structure, polysaccharide, AFM, hypoglycemic activity, Sanghuangporus sanghuang

13C NMR data:
Linkage	Residue	C1	C2	C3	C4	C5	C6
4	aDGlcp	101.28	73.15	74.93	78.35	72.77	61.87
4,4,4,4	aDGlcp	101.28	73.15	74.93	78.35	72.77	61.87
4,4,4,6,4	aDGlcp	101.28	73.40	74.33	70.94	73.42	61.89
4,4,4,6	aDGlcp	100.19	73.40	74.93	78.35	71.97	61.89
4,4,4	aDGlcp	101.37	73.42	74.93	79.24	71.78	69.37
4,4,6,4,4	aDGlcp	101.28	73.40	74.33	70.94	73.42	61.89
4,4,6,4	bDGalp	105.96	74.41	74.87	79.24	76.11	62.34
4,4,6	aDGlcp	100.19	73.40	74.93	78.35	71.97	61.89
4,4	aDGlcp	101.37	73.42	74.93	79.24	71.78	69.37
	aDGlcp	101.28	73.15	74.93	78.35	72.77	61.87


1H NMR data:
Linkage	Residue	H1	H2	H3	H4	H5	H6
4	aDGlcp	5.32	3.56	3.89	3.57	3.77	3.70-3.78
4,4,4,4	aDGlcp	5.32	3.56	3.89	3.57	3.77	3.70-3.78
4,4,4,6,4	aDGlcp	5.32	3.52	3.63	3.34	3.70	3.70-3.78
4,4,4,6	aDGlcp	4.90	3.52	3.93	3.57	3.96	3.68-3.81
4,4,4	aDGlcp	5.28	3.58	3.90	3.55	3.83	3.82-3.86
4,4,6,4,4	aDGlcp	5.32	3.52	3.63	3.34	3.70	3.70-3.78
4,4,6,4	bDGalp	4.56	3.60	3.70	4.09	3.65	3.66-3.78
4,4,6	aDGlcp	4.90	3.52	3.93	3.57	3.96	3.68-3.81
4,4	aDGlcp	5.28	3.58	3.90	3.55	3.83	3.82-3.86
	aDGlcp	5.32	3.56	3.89	3.57	3.77	3.70-3.78


1H/13C HSQC data:
Linkage	Residue	C1/H1	C2/H2	C3/H3	C4/H4	C5/H5	C6/H6
4	aDGlcp	101.28/5.32	73.15/3.56	74.93/3.89	78.35/3.57	72.77/3.77	61.87/3.70-3.78
4,4,4,4	aDGlcp	101.28/5.32	73.15/3.56	74.93/3.89	78.35/3.57	72.77/3.77	61.87/3.70-3.78
4,4,4,6,4	aDGlcp	101.28/5.32	73.40/3.52	74.33/3.63	70.94/3.34	73.42/3.70	61.89/3.70-3.78
4,4,4,6	aDGlcp	100.19/4.90	73.40/3.52	74.93/3.93	78.35/3.57	71.97/3.96	61.89/3.68-3.81
4,4,4	aDGlcp	101.37/5.28	73.42/3.58	74.93/3.90	79.24/3.55	71.78/3.83	69.37/3.82-3.86
4,4,6,4,4	aDGlcp	101.28/5.32	73.40/3.52	74.33/3.63	70.94/3.34	73.42/3.70	61.89/3.70-3.78
4,4,6,4	bDGalp	105.96/4.56	74.41/3.60	74.87/3.70	79.24/4.09	76.11/3.65	62.34/3.66-3.78
4,4,6	aDGlcp	100.19/4.90	73.40/3.52	74.93/3.93	78.35/3.57	71.97/3.96	61.89/3.68-3.81
4,4	aDGlcp	101.37/5.28	73.42/3.58	74.93/3.90	79.24/3.55	71.78/3.83	69.37/3.82-3.86
	aDGlcp	101.28/5.32	73.15/3.56	74.93/3.89	78.35/3.57	72.77/3.77	61.87/3.70-3.78

There is only one chemically distinct structure:

SVGMWSMILES3D molIonize

 

Warning = sub-repeat ending at aDGlcp: large unit count (8) was reduced to 5
[*]O[C@@H]1[C@@H](CO)O[C@H](O[C@@H]2[C@@H](CO[C@H]3O[C@H](CO)[C@@H](O[C@H]4O[C@H](CO)[C@@H](O)[C@H](O)[C@H]4O)[C@H](O)[C@H]3O)O[C@H](O[C@@H]3[C@@H](CO[C@H]4O[C@H](CO)[C@@H](O[C@@H]5O[C@H](CO)[C@H](O[C@H]6O[C@H](CO)[C@@H](O)[C@H](O)[C@H]6O)[C@H](O)[C@H]5O)[C@H](O)[C@H]4O)O[C@H](O[C@@H]4[C@@H](CO)O[C@H](O[C@@H]5[C@@H](CO)O[C@H](O[C@@H]6[C@@H](CO)O[C@H](O[C@@H]7[C@@H](CO)O[C@H](O[C@@H]8[C@@H](CO)O[C@H](O[C@@H]9[C@@H](CO)O[C@H]([*])[C@H](O)[C@H]9O)[C@H](O)[C@H]8O)[C@H](O)[C@H]7O)[C@H](O)[C@H]6O)[C@H](O)[C@H]5O)[C@H](O)[C@H]4O)[C@H](O)[C@H]3O)[C@H](O)[C@H]2O)[C@H](O)[C@H]1O

2269.974 g/mol (C₈₄H₁₄₀R₂O₇₀, R = next and previous repeats, not counted in mol weight)