Cystine is the oxidized dimer form of the amino acid cysteine. Cystine serves two biological functions, a site of redox reactions and a mechanical linkage that allows proteins to retain their 3-dimensional structure. It is common in many foods such as eggs, meat, dairy products, and whole grains as well as skin, horns and hair. Human hair and skin contain approximately 10–14% cystine by mass. Cysteine supplements are sometimes marketed as anti-aging products with claims of improved skin elasticity. Cysteine is more easily absorbed by the body than cystine, so most supplements contain cysteine rather than cystine. N-acetyl-cysteine (NAC) is better absorbed than other cysteine or cystine supplements.

Cholesterol is a sterol (a combination steroid and alcohol) and a lipid found in the cell membranes of all body tissues, and transported in the blood plasma of all animals. The high level of cholesterol in the blood is a marker of hypercholesterolemia, also called dyslipidemia. As a part of homeopathic product, it helps to support general liver and gallbladder health, and is used for temporary relief of symptoms related to adrenal glands such as fatigue and low energy. Cholesterol binds to and affects the gating of a number of ion channels such as the nicotinic acetylcholine receptor (nAChR) Inwardly-rectifying K+ channels (Kir); Transient receptor potential vanilloid 1 channels (TRPV1) and Large-conductance Ca2+-sensitive voltage-gated K+ channels (BK). It was shown the new mechanistic insights into the role of cholesterol in the regulation of nAChR, showing that cholesterol regulates the channels by two distinct mechanisms: stabilization of the channels in a resting state that depends on specific lipid-protein interactions and facilitation of the transitions between uncoupled and coupled states that depends on the hydrophobic thickness of the membrane

Colfosceril palmitate (dipalmitoylphosphatidylcholine) is a synthetic pulmonary surfactant, which is used in infants with respiratory distress syndrome it was approved in 1990, but nowadays it is under the state of canceled post-marketing. Colfosceril palmitate is reducing the tension and stabilizing the alveoli from collapsing.

D-Xylose is a sugar originally isolated from wood. D-Xylose is a colorless to white crystalline powder that is used in food products such as breads, butter, and beverage industry as flavoring agent and sweetener. Specifically, D-Xylose is used to sweeten products intended for use by obese and diabetic customers because it is a non-caloric sweetener. It has a cool and refreshing taste and has the same sweetness as sucrose, and it is often used to sweeten a wide variety of foods and beverages such as spices, meat products, butter, etc. D-Xylose is a sugar widely used as diabetic sweetener in food and beverage. is a sugar first isolated from wood, and named for it. Xylose is classified as a monosaccharide of the aldopentose type, which means that it contains five carbon atoms and includes a formyl functional group. It is derived from hemicellulose, one of the main constituents of biomass. Like most sugars, it can adopt several structures depending on conditions. With its free carbonyl group, it is a reducing sugar. D-xylose absorbtion test has been used for diagnosis of intestinal malabsorption.

Tryptophan is alpha-aminoacid that is used in the biosynthesis of proteins. It is essential aminoacid in humans, meaning the body cannot synthesize and it must be obtained from the diet. Tryptophan is a precursor of serotonin, and as such is sold over the counter in many countries as a dietary supplement for use as an antidepressant, anxiolytic and sleep aid, however application of tryptophan in these indications is not approved by FDA.

Alanine is a non-essential aminoacid encoded by GCU, GCC, GCA, and GCG codons. Besides being a building block of proteins, alanine plays a key role in glucose-alanine cycle. Alanine is medically used as a dietary supplement for conditions such as fructose intolerance, muscle atrophy, low birth weight.

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.