Deep eutectic solvent extraction of Tremella fuciformis polysaccharide and the extract's antioxidant activity

No study has, until now, examined the deep eutectic solvent (DES) extraction of Tremella fuciformis polysaccharide (TFP). In this study, a DES composed of choline chloride and citric acid (1:1 molar ratio) was prepared for TFP extraction. Artificial neural network optimization based on genetic and sparrow search algorithms was applied, yielding the polysaccharide TFP-1 with an average molecular weight of 13 152 Da.

The TFP-1 polysaccharide exhibited a triple-helix structure, and its polymer chains comprised glucose, mannose, xylose, and galactose in a molar ratio of 90.82:5.68:3.06:0.44. The main chain structure was →(6)-β-d-Glcp-(1→, →4)-α-d-Glcp-(1→, →3,6)-α-d-Glcp-(1→, →4,6)-α-d-Glcp-(1→). In a cigarette smoke extract (CSE)-induced oxidative injury cell model, the TFP-1-based extract (TFP-1-E) decreased interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and nuclear factor erythroid 2-related factor 2 (Nrf2) levels, while increasing superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) activity at 50-100 μg mL⁻¹ compared with the model group. RNA sequencing (RNA-Seq) analysis identified 1343 differentially expressed genes between the CSE and TFP-1-E groups, which were primarily mapped to a five-gene sub-network comprising CARD17, CARD18, CASP1, MINDY3, and MINDY2.

These data suggest that TFP-1-E could alleviate inflammation and oxidative stress and could be used for the development of functional foods or biomedicines. © 2025 Society of Chemical Industry.