DL-5-hydroxytryptophan, 5-HTP is a serotonin precursor. It was discovered on the rats, that the pharmacological responses and changes in brain 5-hydroxytryptamine (5-HT) concentration elicited following the administration of 5-HTP did not reflect changes in the concentration of endogenous brain 5-HT. The biochemical and pharmacological properties of the 5-HTP-induced increases in brain 5-HT concentration were distinctly different from those of increases in the endogenous content of the amine. In normal rats, administered 5-HTP, observable pharmacological responses were not elicited, despite equal or even larger increases in brain 5-HT concentration.

3-Tyrosine, in contrast to the para isomer, is readily racemized. The majority of the load was metabolized to m-hydroxyphenylacetic acid but m-hydroxymandelic acid and 3,4-dihydroxyphenylacetic acid were also detected. Low circulating levels of m-tyrosine in the plasma suggest that most of the load is held due to a first pass effect somewhere in the enterohepatic system and that this portion of the load is not in equilibrium with the plasma m-tyrosine. The metabolism of a m-tyrosine may give further insight into the deficiencies of the phenylalanine hydroxylating system found in the various phenotypes of phenylketonuria. 3-Tyrosine has been used experimentally as a substitute for L-DOPA in the treatment of Parkinsonism. 3-tyrosine mimics the action of Dopa in two experimental animal models. It was also obvious from the experiments with d,l- and l-m-tyrosine that only the l-isomer (3-Tyrosine) is active.

Gibberellic acid was first discovered in Japan in 1935 as a result of the study of a condition common in rice plants called "foolish seedling" disease, which caused the plants to grow much taller than normal. The effects of gibberellins weren't widely understood until years later. Gibberellic acid, GA3 is a naturally occurring plant hormone that regulates the growth of plants, including triggering seed germination. Gibberellic Acid is not manufactured; it's a natural product extracted from the Gibberella fujikuroi fungus. There are over 100 known forms of gibberellic acid; GA3 is the most effective. Gibberellic acid (GA3) is used extensively in Egypt and other countries, to increase the growth of many fruits (such as strawberries and grapes) and vegetables (such as tomatoes, cabbages and cauliflower). Carcinogenic effect of Gibberellic acid has being demonstrated in several studies. Gibberellic acid increased the activity of testicular 3β-HSD and 17β-HSD and elevated testosterone content in rats, acting as an agonist of steroidogenesis in male rats. Gibberellic acid has being suggested to promote ulcer-healing, healing of surgical wounds or open fractures and treatment of bronchitis or thrombophlebitis in animals including humans.