Syno-Vital Oral Hyaluronic Acid Plus Vitamin C sachets provide Hyaluronic Acid from a vegetarian source. Hyaluronic Acid is a special mucopolysaccharide occurring naturally throughout the human body. It is found in the greatest concentrations in the synovial fluid of joints, the vitreous humour (fluid) of the eye, and most abundantly in the skin. As we age, our bodies may produce less and less hyaluronic Acid.