L-Hydroxyproline from China H&Z® is a nonessential amino acid, which means that it is manufactured from other amino acids in the liver; it does not have to be obtained directly through the diet.Hydroxyproline is necessary for the construction of the body's major structural protein, collagen. Defects in carcinoma synthesis lead to easy bruising, physical bleeding, breakdown of connective tissue of the ligaments and tendons, and increased risk to blood vessel damage. Increased spill of hydroxyproline in The urine is generally associated with breakdown of connective tissue due to disease process and may also be a manifestation of vitamin C deficiency.