β-Endorphin, an endogenous opioid neuropeptide, is an opioid receptor agonist. β-Endorphin binds preferentially to μ-opioid receptors and is produced in certain neurons of the central and peripheral nervous system and is one of three endorphins produced in humans. β-Endorphin can be used to reduce stress and maintain homeostasis in the body and is involved in neurological pain perception regulation.

The herbs of Glebionis coronaria.

Norvaline is a non-proteinogenic branched-chain amino acid. It has previously been reported to be a natural component of an antifungal peptide of Bacillus subtilis. Norvaline and other modified branched chain amino acids have received attention in recent studies as they appear to be incorporated in some recombinant proteins found in E. coli.