Structural characterization and immunoregulatory activity of a novel acidic polysaccharide from Scapharca subcrenata

• Published in: International journal of biological macromolecules Vol. 210; pp. 439 - 454
• Main Authors: Li, Hang, Li, Jianhuan, Shi, Hui, Li, Chunlei, Huang, Weijuan, Zhang, Man, Luo, Yuanyuan, Song, Liyan, Yu, Rongmin, Zhu, Jianhua
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15.06.2022
• Subjects: Acidic polysaccharide; Scapharca subcrenata; Structural characterization and immunoregulatory activity; Structural characterization and immunoregulatory activity; Scapharca subcrenata; Acidic polysaccharide
• ISSN: 0141-8130; 1879-0003
• DOI: 10.1016/j.ijbiomac.2022.04.204

A novel acidic polysaccharide named SSPA50–1 was isolated from Scapharca subcrenata using a simulated gastric fluid extraction method. SSPA50–1 is a heteropolysaccharide with an average molecular weight of 44.7 kDa that is composed of galacturonic acid, glucose, galactose, mannose, ribose, rhamnose, fucose, xylose and arabinose at a molar ratio of 1.00:5.40:9.04:3.10:1.59:4.01:2.10:2.21:2.28. The structural characterization based on the methylation and 1D/2D NMR analyses indicated that SSPA50–1 is composed of →3)-β-L-Rhap-(1→, →3)-β-L-2-O-Me-Fucp-(1→, →2)-α-D-Xylp-(1→, →5)-α-L-Araf-(1→, →3)-β-D-Galp-(1→, →6)-α-D-Glcp-(1→, →3,4)-β-D-Manp-(1→, →3,4)-β-D-Galp-(1→, β-D-Ribf-(1→, α-D-Glcp-(1→, and α-D-GalAp6Me-(1→. Furthermore, SSPA50–1 possessed potent immunoregulatory activity by enhancing the phagocytosis and NO, iNOS, TNF-α and IL-6 secretion capacity of RAW264.7 cells. Otherwise, SSPA50–1 significantly promoted the proliferation of splenic lymphocytes and RAW264.7 macrophages. These results indicated that SSPA50–1 could be developed as a potential ingredient for immunostimulatory agents. •The novel acidic Scapharca subcrenata polysaccharide (SSPA50–1) was isolated.•SSPA50–1 is a heteropolysaccharide that composed of 9 types of monosaccharide.•GalA was first found in the polysaccharides of S. subcrenata.•SSPA50–1 promoted the proliferation of RAW264.7 macrophages and splenocytes.•SSPA50–1 increased the secretion of NO, IL-6 and TNF-α in RAW264.7 cells.