Structure identification of a polysaccharide in mushroom Lingzhi spore and its immunomodulatory activity

Zhili Sheng; Lingrong Wen; Bao Yang

doi:10.1016/j.carbpol.2021.118939

Structure identification of a polysaccharide in mushroom Lingzhi spore and its immunomodulatory activity

Carbohydr Polym. 2022 Feb 15:278:118939. doi: 10.1016/j.carbpol.2021.118939. Epub 2021 Nov 26.

Authors

Zhili Sheng¹, Lingrong Wen², Bao Yang³

Affiliations

¹ Guangdong Provincial Key Laboratory of Applied Botany, Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, Core Botanical Gardens, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; College of Food Science and Engineering, Jilin Agricultural University, Changchun 130118, China.
² Guangdong Provincial Key Laboratory of Applied Botany, Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, Core Botanical Gardens, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.
³ Guangdong Provincial Key Laboratory of Applied Botany, Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, Core Botanical Gardens, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: yangbao@scbg.ac.cn.

PMID: 34973757
DOI: 10.1016/j.carbpol.2021.118939

Abstract

Ganoderma lucidum spore serves as a well-known immunomodulatory functional food in Asia. The polysaccharides in G. lucidum spore are responsible for the claimed immunomodulatory activity. However, the structural information of polysaccharides remains unclear. In this work, the leading water-soluble polysaccharide in G. lucidum spore (GLSP-I) with a molecular weight of 128.0 kDa was isolated and purified. The monosaccharide composition analysed by gas chromatography indicated that GLSP-I was a glucan. Three side chains, including Glc-(1 → 3)-Glc-(1 → 3)-Glc-(1 → 6)-Glc, Glc-(1 → 6)-Glc-(1 → 6)-Glc-(1 → 6)-Glc and Glc-(1 → 3)-Glc-(1 → 3)-Glc-(1 → 3)-Glc-(1 → 3)-Glc, were identified by UPLC-MS/MS. The structural characteristics were further identified by NMR spectra. The results indicated that the backbone of GLSP-I was (1 → 3)-β-D-glucan, with side chains linking at O-6. The proposed structure was drawn as below. The immunomodulatory activity assay indicated that GLSP-I could activate macrophages in a dose-dependent manner.

Keywords: Ganoderma lucidum spore; Glucan; Macrophage activation; NMR; UPLC-MS/MS.

MeSH terms

Carbohydrate Conformation
Immunologic Factors / chemistry
Immunologic Factors / pharmacology*
Immunomodulation / drug effects*
Polysaccharides / chemistry
Polysaccharides / pharmacology*
Reishi / chemistry*
Spores, Fungal / chemistry*

Substances

Immunologic Factors
Polysaccharides