Oligopeptide-34 — a synthetically manufactured peptide containing 13 amino acids (including arginine). Oligopeptide-34 decreases melanin synthesis and tyrosinase enzyme activity in melanocytes, decreasing the transfer of melanosomes to new keratinoycte cells. Studies in the laboratory using human melanocytes and Melanocyte-Stimulating Hormone (MSH, the hormone that signals the melanocyte to start melanin production) show expected production of melanin in 72 hours. In test tubes where Oligopeptide-34 was added, the amount of melanin production was significantly reduced by about 33%. Additional studies indicated a reduction in tyrosinase enzyme activity by 65%. Studies comparing Oligopeptide-34 to Vitamin C and Arbutin showed Oligopeptide-34 to be superior; Vitamin C and Arbutin reduced pigmentation by 27% and 40%, respectively, while Oligopeptide-34 reduced pigmentation by 47%.