Quantitative detection of β-glucans in Cordyceps species using a validated Congo red assay

β-Glucan is extensively utilized in the food industry for its functional benefits, including blood glucose and lipid regulation, enhanced food texture, and a prolonged shelf life. In the pharmaceutical field, it serves as a potent immune modulator, anti-tumor agent, and vaccine adjuvant, highlighting its significant biological potential. Despite its wide-ranging applications, standardized methods for detecting β-glucan in Cordyceps species have been lacking. To address this deficiency, the current study developed a Congo Red Ultraviolet Spectrophotometry assay for β-glucan quantification. The optimal conditions for extraction were identified as dimethyl sulfoxide (DMSO) being the solvent, a pH of 7.0, a temperature of 65 °C, and a reaction time of 60 min. Validation tests confirmed the method's precision, reproducibility, and stability, demonstrating its reliability for β-glucan analysis. The assay was applied to three Cordyceps species, i.e., Cordyceps militaris, C. cicadae, and C. fumosorosea. Results revealed a marginally higher β-glucan content in C. fumosorosea compared to the other species. This efficient and cost-effective method offers a valuable tool for β-glucan analysis, with potential applications in quality control and product development for medicinal and edible fungi. Future research should extend to additional Cordyceps species and compare results with alternative analytical techniques to further enhance standardization and broaden the applicability of this method.