Metacresol (m-cresol or 3-methylphenol) is colorless, yellowish liquid. It is used as a bactericide for control of crown gall and olive knot on certain fruit and nut trees and ornamentals and the genetic/physiological disorder burr knot on apples. Currently, one product is registered which contains both m-cresol and xylenol. Used as disinfectant/bacteriocide/germicide for animal pathogenic bacteria (G- and G+ vegetative) in households, sickrooms, hospitals, veterinary clinics, and veterinary hospitals; on surgical instruments, diagnostic instruments/equipment and on hospital critical rubber/plastic items. Used as an insecticide and miticide on dogs for treatment of lice and fleas. It is also used for making synthetic resins; in photographic developers, explosives. Additionally, m-cresol is chemical intermediate for thymol used in cough/cold medicinals, synthetic pyrethroid insecticides, 3-methyl-6-t-butylphenol, trinitro-m-cresol for explosives, and phenolic resins; disinfectant ingredient; ore flotation agent; solvent. m-Cresol, either pure or mixed with p-cresol, is important in the production of contact herbicides. m-Cresol is also a precursor to the pyrethroid insecticides. Furthermore, many flavor and fragrance compounds, such as (-)-methanol and musk ambrette, are derived from m-cresol. Several important antioxidants including synthetic vitamin E are produced from m-cresol. m-cresol is used as a topical dental antiseptic. m-cresol is an effective antimicrobial preservative and is used at low levels (0.3%) in multi-dose peptide and protein formulations. m-cresol has been shown to cause protein aggregation.

Phenylalanine is a biologically essential amino acid that acts as a precursor to tyrosine and the catecholamines (epinephrine, norepinephrine, dopamine, and tyramine), and is a constituent of many central nervous system neuropeptides. Normal dietary levels of phenylalanine are approximately 1-2 grams daily. Phenylalanine appears in two forms which are identical mirror images of each other: L-phenylalanine, a nutritional supplement, and D-phenylalanine, an effective painkiller and antidepressant due to its ability to inhibit the breakdown of enkephalins, the brain’s natural pain killers.

Isoleucine is an essential α-amino acid that is used in the biosynthesis of proteins. L-isoleucine is commonly used in parenteral and enteral nutrition. It is used in combination with the other branched chain amino acids to improve the nutritional status of patients with hepatic diseases. BCAAs serve as important fuel sources for skeletal muscle during periods of metabolic stress

Lysing is an essential basic amino-acid encoded by codone AAA and AAG, and used in the biosynthesis of proteins. The daily requirement for lysine is 38 mg/kg body weight. The most rich source of lysine is fish, beef, chicken. In a clinical study lysine supplements was found to be an effective for reduction of occurrence, severity and healing time for recurrent HSV infection, however Cochrane Review concluded that the evidence is insufficient. Lysine was investigated for improving anxiety, ameliorating angina prectoris. Lysine acetylsalicylate has been used to treat pain and to detoxify the body after heroin use. Lysine clonixinate has been used for its analgesic properties for the treatment of migraine headaches and other painful conditions. However, limited clinical trials exist for these conditions.

Histidine is an essential amino acid. L-histidine is converted to histamine by histidine decarboxylase, a pyridoxal 5'-phosphate-dependent enzyme. The copper(II)–l-histidine (1:2 complex at physiological pH) has been widely used in the treatment of Menkes disease (a genetic neurodegenerative disorder that leads to early death in the children due to impaired copper metabolism) and more recent use has been reported in the treatment of infantile hypertrophic cardioencephalomyopathy (a condition caused by mutations in SCO2, a cytochrome c oxidase assembly gene). CUSTODIOL HTK (Histidine-tryptophan-ketoglutarate) Solution is indicated for perfusion and flushing of donor kidneys, liver, and heart prior to removal from the donor or immediately after removal from the donor.

Beta-carotene is found in many foods and is sold as a dietary supplement. Beta-carotene is a carotenoid, weak antioxidant; precursor of vitamin A, which is essential for vision and growth. Used to reduce the severity of photosensitivity reactions in patients with erythropoietic protoporphyria (EPP). Has been used in high-dose antioxidant supplements containing ascorbic acid and vitamin E with zinc in high-risk patients with age-related macular degeneration. Beta-carotene is also used to decrease asthma symptoms caused by exercise; to prevent certain cancers, heart disease, cataracts; and to treat AIDS, alcoholism, Alzheimer’s disease, depression, epilepsy, headache, heartburn, high blood pressure, infertility, Parkinson’s disease, rheumatoid arthritis, schizophrenia, and skin disorders including psoriasis and vitiligo.

Tyrosine (L-form) is a non-essential amino acid, which is primarily required for the protein synthesis. This amino acid is the precursor of dopamine, norepinephrine, and epinephrine; therefore the lower concentration of tyrosine could be a peripheral marker of the hyperdopaminergic condition hypothesized to explain psychosis. Tyrosine supplements can improve cognition, increase energy, reduce anxiety, reduce depression, reduce levels of pain.

Pelargonic acid (also called as nonanoic acid), a naturally found in a variety of plants and food products is a cosmetic ingredient, that function as skin-conditioning agent. The Food and Drug Administration (FDA) has approved pelargonic acid as a food additive, and as an ingredient in solutions used commercially to peel fruits and vegetables. FDA considers it safe for humans to eat food containing small amounts of pelargonic acid.