DL-Arginine is an alpha amino-acid and can be found as a metabolite and as a reagent for biological molecules.

Dimethylsulfoxide (DMSO) is a very polar organic compound that is useful in organic chemistry for solubilizing organic and inorganic compounds. DMSO is also used as a cryoprotectant for cell media, preventing the formation of ice crystals, which would otherwise damage cells. DMSO can be used in PCR reactions to inhibit the self-complementation of DNA or PCR primers and increase amplification, especially for DNA sequences, which have GC rich sequences.

Hydrocortisone is a glucocorticoid primarily produced by the adrenal cortex. It is used as an anti-inflammatory and is researched for its immunosuppressive and for glucose metabolism regulation. Hydrocortisone completes its action on a wide scale by binding glucocorticoid receptors which upregulates anti-inflammatory protein synthesis.

Idebenone is a synthetic analog of ubiquinone (CoQ10). It scavenges free radicals and acts as an antioxidant. Idebenone differs from ubiquinone by having a shorter, less lipophilic tail and thus can function in multiple cellular environments. In contrast to ubiquinone, idebenone acts as a competitive inhibitor of complex I in the electron transport chain and is capable of facilitating cellular respiration that is independent of a functioning complex I. It can accept electrons from the glycerophosphate shuttle, NADH-quinone oxidoreductase, and complex II of the electron transport chain. Idebenone was originally developed to treat cognitive disorders such as Alzheimer’s disease, but was not found to be effective so other uses are being explored.

L-Arabinose is an arabinose isomer widely found in nature, while D-arabinose is less common. L-Arabinose is a constituent of many biopolymers that make up plant cell walls.

This monosaccharide is often used in cell culture media, serving as a bacterial carbon source, and can be used to distinguish between bacteria based on their fermentation abilities.

L-Arabinose, in the absence of glucose, induces transcription of the ara operon in E. coli that encodes L-arabinose catabolizing enzymes. It does this by binding to the AraC protein and activating the PBAD promoter. The PBAD promoter is used in plasmid vectors as a switch for protein expression that can be turned on by L-arabinose or turned off by addition of glucose.

L-Arabitol is the reduced alcohol form of L-arabinose. It is produced by some fungus from enzymatic reduction of L-arabinose. L-Arabitol is metabolized by a variety of different bacteria and fungus utilizing an arabitol dehydrogenase enzyme. Arabitol dehydrogenase genes have been introduced into plants to serve as a positive selection marker for transgenic cells. L-Arabitol has been shown to be an inducer of a hydrolytic xylanase enzyme used for catabolism of L-xylose in the saprophytic fungus Hypocrea jecorina.

Arginine is an essential amino acid found in food and plant sources, and many biological systems and is one of only 3 amino acids with basic side chains. Arginine is typically classified as a semi-essential or conditionally essential amino acid. Administered intravenously, Arginine has been shown to stimulate the secretion of human growth hormone and is frequently used in growth hormone stimulation tests. L-Arginine is a substrate of nitric oxide synthase, which is converted to citrulline and nitric oxide and is known to Induces insulin release by a nitric oxide-dependent mechanism.

L-Lactic acid is the biologically active isomer of Lactic Acid. In animals, it is constantly produced from pyruvate via the enzyme lactate dehydrogenase (LDH) in a process of fermentation during normal metabolism and exercise. It can also be used to create biodegradable polymers.

Sorbose is a ketose belonging to the group of sugars known as monosaccharides. L-Sorbose is the configuration of the naturally-occurring sugar and has a sweetness equivalent to that of sucrose. L-Sorbose is often used as a starting reagent for the biosynthesis of ascorbic acid and forms a colorless, clear solution when dissolved in water.

Tryptophan is an essential amino acid in the human diet. Its functions as a serotonin precursor have increased interest in its ability to treat depression and epilepsy; however, there has been inconclusive evidence in clinical trials regarding its efficacy in humans. Safety has also been a concern.

It is widely used in molecular genetics as an auxotrophic genetic marker in yeast gene disruption experiments.