Quercetin, Bromelain, Vitamin C complex. Quercetin is one of the most well known Non-Citrus bioflavonoids. Flavonoids help maintain normal capillary permeability. Bromelain is the famous enzyme from Pineapple and has been valued for many years. Vitamin C is an important nutrient and provides nutritive support for normal, healthy collagen synthesis, supports the development of cartilage and bone, immune function, capillary and blood vessel integrity, healthy skin, and nerve impulse transmission.