Sanghuangporus baumii, is a widely used medicinal fungus. The polyphenols extracted from this fungus exert antioxidant, anti-inflammatory, and hypoglycemic effects. In this study, polyphenols from the fruiting bodies of S. baumii were obtained using the deep eutectic solvent (DES) extraction method. The factors affecting the extraction yield were investigated at different conditions. Based on the results from single-factor experiments, response surface methodology was used to optimize the extraction conditions. The scavenging ability of the polyphenols on •OH, DPPH, and ABTS⁺ was determined. The results showed that the DES system composed of choline chloride and malic acid had the best extraction yield (6.37 mg/g). The optimal extraction parameters for response surface methodology were as follows: 42 min, 58 ℃, 1:34 solid–liquid (mg/mL), and water content of 39%. Under these conditions, the yield of polyphenols was the highest (12.58 mg/g). At 0.30 mg/mL, the scavenging ability of the polyphenols on •OH, DPPH, and ABTS⁺ was 95.71%, 91.08%, and 85.52%, respectively. Thus, the method using DES was more effective than the conventional method of extracting phenolic compounds from the fruiting bodies of S. baumii. Moreover, the extracted polyphenols exhibited potent antioxidant activity.

Background: Antrodia cinnamomea, a rare medicinal fungus, has been increasingly studied in recent years because of its abundant secondary metabolites which are beneficial to humans. However, there is a lack of research on its polyphenols which are of good research value due to their antioxidant, anti-inflammatory, hypoglycemic and other activities. Results: In this study, the effects of different extraction conditions on the yield of its polyphenols were investigated. Deep-Eutectic Solvents composed of choline chloride and malonic acid had the best extraction efficiency, with the optimal extraction conditions being as follows: a solid–liquid ratio of 40 mg/mL, an extraction temperature of 55 °C, an extraction time of 70 min and a DES with 20% water content. Under these conditions, the extraction yield of polyphenols reached 22.09 mg/g which was about 2 times that of alcohol-based extraction (10.95 mg/g). In vitro antioxidant test results further showed that polyphenols from A. cinnamomea had strong antioxidant activities. When the concentration of polyphenols reached 0.1 mg/mL of polyphenols, the scavenging activity of free radical basically reached its maximum, with values of 94.10%, 83.34% and 95.42% for DPPH, ABTS⁺ and ·OH scavenging. In this case, the corresponding IC₅₀ values were 0.01, 0.014 and 0.007 mg/mL, respectively. Conclusions: This study lays the foundation for the efficient extraction and application of polyphenols from A. cinnamomea.