Isolation, structural characterization and immunomodulatory activity on RAW264.7 cells of a novel exopolysaccharide of Dictyophora rubrovalvata

Mingyang Song; Jiawen Wang; Kaisheng Bao; Chong Sun; Xiaolei Cheng; Tengda Li; Shanshan Wang; Siqiang Wang; Tingchi Wen; Zhenyuan Zhu

doi:10.1016/j.ijbiomac.2024.132222

Isolation, structural characterization and immunomodulatory activity on RAW264.7 cells of a novel exopolysaccharide of Dictyophora rubrovalvata

Int J Biol Macromol. 2024 May 8;270(Pt 2):132222. doi: 10.1016/j.ijbiomac.2024.132222. Online ahead of print.

Authors

Affiliations

¹ State Key Laboratory of Food Nutrition and Safety, Tianjin University of Science and Technology, Tianjin 300457, PR China; Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin University of Science and Technology, Tianjin 300457, PR China; College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457, PR China.
² Guizhou Panzheng Agriculture Ltd., PR China; National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Guiyang 550025, PR China; The Engineering Research Center of Southwest Bio-Pharmaceutical Resources, Ministry of Education, Guizhou University, Guiyang 550025, PR China.
³ State Key Laboratory of Food Nutrition and Safety, Tianjin University of Science and Technology, Tianjin 300457, PR China; Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin University of Science and Technology, Tianjin 300457, PR China; College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457, PR China; Guizhou Panzheng Agriculture Ltd., PR China. Electronic address: zhyuanzhu@tust.edu.cn.

PMID: 38729468
DOI: 10.1016/j.ijbiomac.2024.132222

Abstract

Fungal polysaccharides have been explored by many for both structural studies and biological activities, but few studies have been done on the extracellular polysaccharides of Dictyophora rubrovalvata, so a new exopolysaccharide was isolated from Dictyophora rubrovalvata and its structure and its immunological activity were investigated. The crude exopolysaccharide (EPS) was purified by DEAE52 cellulose and Sephadex G-200 to obtain a new acidic polysaccharide (DR-EPS). DR-EPS (2.66 × 10³ kDa) was consisted mainly of mannose, glucose, galactose and glucuronic acid with a molar ratio of 1: 0.86: 0.20: 0.01. In addition, DR-EPS increased the phagocytic activity of RAW264.7 cells up to 2.67 times of the blank control group. DR-EPS improved intracellular nucleic acid and glycogen metabolism as observed by AO and PAS staining. DR-EPS(40 μg/mL) promoted NO production up to 30.66 μmol, enhanced acid phosphatase (ACP) and superoxide dismutase (SOD) activities, with activity maxima of 660 U/gprot and 96.27 U/mgprot, respectively, and DR-EPS (160 μg / mL) significantly increased the lysozyme content as 2.73 times of the control group. The good immunological activity of extracellular polysaccharides of Dictyophora rubrovalvata provides directions for the use of fermentation broths.

Keywords: Dictyophora rubrovalvata; Extracellular polysaccharide; Immunomodulatory activity; RAW264.7 cells; Structural characterization.