Red Yeast Rice Derived Carbon Dots with Antiviral Activity to Block Coronavirus Infection

Abstract Red yeast rice (RYR), fermented from Monascus purpureus , has demonstrated anti‐inflammatory, anticancer, antibacterial properties, and potential antiviral activity. However, its low water solubility hampers its broader application. With the growing interest in carbon dots (CDs) for antiviral research, efforts to create new antiviral CDs that are highly compatible with living organisms and have strong antiviral properties have been sped up. In this study, the hydrothermal approach was employed to synthesize highly biocompatible CDs (abbreviated as RYR‐CDs) using red yeast rice as the precursor. Using porcine epidemic diarrhea virus (PEDV), a coronavirus model, RYR‐CDs were shown to reduce PEDV proliferation by two orders of magnitude, as evidenced by virus titers and N protein expression analysis. Further studies have shown that RYR‐CDs can inhibit absorption, while also triggering the antiviral innate immune response. Additionally, RYR‐CDs have antioxidant ability and can inhibit the increase of ROS content caused by viral infection and inhibit cell apoptosis caused by changes in mitochondrial membrane potential. These findings suggest that RYR‐CDs exert potent antiviral effects through a multifaceted inhibition mechanism, offering food‐derived materials as promising candidates for the treatment of PEDV infections.