Structural properties and anti-inflammatory activity of purified polysaccharides from Hen-of-the-woods mushrooms (Grifola frondosa)

Xiaoyi Liu; Shuai Chen; Huijuan Liu; Jiao Xie; K M Faridul Hasan; Qibing Zeng; Shaofeng Wei; Peng Luo

doi:10.3389/fnut.2023.1078868

Structural properties and anti-inflammatory activity of purified polysaccharides from Hen-of-the-woods mushrooms (Grifola frondosa)

Front Nutr. 2023 Feb 7:10:1078868. doi: 10.3389/fnut.2023.1078868. eCollection 2023.

Authors

Xiaoyi Liu¹, Shuai Chen², Huijuan Liu¹, Jiao Xie¹, K M Faridul Hasan³, Qibing Zeng¹, Shaofeng Wei¹, Peng Luo¹

Affiliations

¹ The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Department of Nutrition and Food Hygiene, School of Public Health, Guizhou Medical University, Guiyang, China.
² Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Guizhou Medical University, Guiyang, China.
³ Simonyi Károly Faculty of Engineering, University of Sopron, Sopron, Hungary.

Abstract

Grifola frondosa is an edible medicinal mushroom that has been proven to have a variety of health benefits. The main active ingredients of this mushroom are polysaccharides. In this study, ultrasonic-assisted extraction was used to obtain crude Grifola frondosa polysaccharides (GFPs). Then, purified GFP was obtained after purification. The optimum extraction conditions were an extraction time of 71 min, an extraction temperature of 90°C in a solid-to-liquid ratio of 1:37 g/mL, and an ultrasonic power of 500 W. GFP was purified using DEAE-52 and Sephadex G-100. The structural characterization of GFP was performed using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), ion chromatography (IC), and ultraviolet (UV) visible photometry. The morphology of GFP was analyzed by scanning electron microscopy (SEM), thermogravimetric differential scanning calorimetry (TG-DSC), and Congo red testing. In addition, the administration of GFP in oxazolone (OXZ)-induced ulcerative colitis (UC) in mice was found to prevent weight loss. Different doses of GFP (80, 160, and 320 mg/kg body weight) were used, and sulfapyridine (SASP) was used as a positive control (370 mg/kg body weight) for the treatment of OXZ-induced UC. After treatment, the mice were killed, and blood and colon tissue samples were collected. GFP was found to prevent decreases in colon length and the levels of leukocytes, platelets, and neutrophils in UC mice. Moreover, GFP also decreased the expression of pro-inflammatory cytokines [tumor necrosis factor (TNF)-α and interleukin (IL)-1 β], increased IL-10, and reduced colon injury in UC mice. The results showed that Under these conditions, the predicted polysaccharide yield was 21.72%, and the actual extraction rate was 21.13%. The polysaccharide composition (molar ratio) was composed of fucose (0.025), glucosamine hydrochloride (0.004), galactose (0.063), glucose (0.869), and mannose (0.038). GFP was also found to have a typical absorption peak, and the GFP extracted using the ultrasound-assisted extraction protocol was mainly β-glucan. These results indicate that ultrasound-assisted extraction of GFP could reduce OXZ-induced intestinal inflammation as a promising candidate for the treatment of UC, with the potential for development as a food supplement to improve intestinal diseases.

Keywords: Grifola frondosa polysaccharides; anti-inflammatory activity; structural properties; ulcerative colitis; ultrasound-assisted extraction.

Grants and funding

This work was supported by the Guizhou Science and Technology Department Support Plan Project (Guizhou Science and Technology Combined Support [2021]134), the National Natural Science Foundation of China (8176057), and the First-Class Discipline Construction Project in Guizhou Province (Public Health and Preventive Medicine, 2017).