Cinnamic acid, a naturally occurring aromatic fatty acid of low toxicity, has a long history of human exposure. The cinnamic acid induces cytostasis and a reversal of malignant properties of human tumor cells in vitro. The cinnamic acid was found to induce cell differentiation as evidenced by morphological changes and increased melanin production in melanoma cells (65). Cinnamic acid does not influence the fungal growth but decreases the yield of the pigment from the mycelium (66).