Enhancing the solubility and stability of Dendrobium officinale flavonoids through interaction with soybean peptides

Flavonoids play a major role in promoting human health, yet their instability in solution greatly limits its industrial utilization. This study aimed to introduce soybean peptides (SP) to improve the stability and solubility of Dendrobium officinale flavonoids (DOFs), and to investigate the effects of their interaction, sterilization and storage. The results revealed that DOFs bind to SP through hydrogen bonding and steric effects, leading to changes in the structure, energy, and activity of DOFs, which resulted in enhanced stability and antioxidant capacity. The sedimentation rate and flavonoid content were measured to be 24.64 ± 0.55%, 3.83 ± 0.14 mg/mL, respectively, at the optimum mass ratio of DOFs and SP of 2:5. After thermal treatment, the flavonoid content and antioxidant activity of the complexes both dramatically enhanced. The optimum sterilization condition was 75 °C for 20 min, while the optimum range of temperatures for storage was 4 ~ 25 °C. These findings provide valuable insights for the processing, preservation and application of flavonoids in the future.