Procyanidin B2 (PCB2), a natural flavonoid found in commonly consumed foods, possess anti-inflammatory, anti-oxidant and anti-cancer activities. Procyanidin B2 activates PPARγ to induce M2 polarization in mouse macrophages. Procyanidin B2 significantly suppresses the activation of NLRP3 inflammasome in the lung tissue induced by paraquat in the rat model.