The short version of epithalamin fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2026-06-11 and is reviewed periodically as new material appears.
Several names circulate for the same molecule, including epitalon, epithalone, epithalamin tetrapeptide, and the sequence code AEDG. A CAS registry number, 307297-39-8, is commonly cited for it, though catalogue entries should be checked against supplier documentation because mislabelled records occur. In its usual form the peptide carries free amino and carboxyl termini and is neither glycosylated nor lipidated. Researchers distinguish the defined tetrapeptide from epithalamin itself, a crude pineal preparation containing many peptides that is not chemically characterised.
Material supplied for laboratory use is normally a lyophilised white to off-white powder that dissolves readily in water and in isotonic saline. Lyophilised cakes are hygroscopic and should be equilibrated to room temperature before opening to limit condensation on the solid. Solutions are typically prepared at milligram-per-millilitre concentrations and divided into single-use aliquots, because repeated freeze–thaw cycles degrade short peptides. Aqueous solutions are far less stable than the dry powder, and identity is usually verified by mass spectrometry alongside purity estimation from reversed-phase high-performance liquid chromatography.
No pharmacopoeial monograph exists for this peptide, so quality rests on the supplier's internal specifications and on whatever independent testing a purchaser arranges. Certificates of analysis differ widely in which tests they report and in the limits applied. The counter-ion introduced during purification, commonly acetate or trifluoroacetate, changes the net peptide content of a given mass of powder, so two samples of equal weight may not contain equal amounts of the active sequence. Third-party laboratories can verify purity, identity, residual solvents, and counter-ion content for a fee, which makes documentation more informative than labelling.
Verification of a sample usually begins with reversed-phase high-performance liquid chromatography, which resolves the peptide from truncated sequences and other impurities and expresses purity as a percentage of total peak area. Mass spectrometry by electrospray ionisation or matrix-assisted laser desorption supplies an independent check, because the measured mass can be compared against the theoretical value for AEDG. Amino acid analysis or tandem mass spectrometry sequencing can confirm residue order. Each of these methods answers a different question: a purity figure does not establish identity, and an identity match does not establish how much of the material is intact peptide.
The molecule is a short, linear, hydrophilic peptide that dissolves readily in water or aqueous buffer. Its principal chemical liabilities are hydrolytic rather than oxidative, since it contains no cysteine, methionine, or tryptophan residues. The aspartate–glycine step is a recognised site for aspartimide formation under mildly acidic or basic conditions, generating isoaspartate and succinimide-related products over time. Desiccated lyophilised powder held at −20 °C is comparatively stable, whereas dilute solutions degrade faster and are best frozen as single-use aliquots rather than thawed repeatedly.
| Property | Value | Notes |
|---|---|---|
| Amino acid sequence | Ala-Glu-Asp-Gly | Linear tetrapeptide, also written AEDG |
| Molecular mass | About 390.35 g/mol | Value calculated from the sequence |
| Appearance | White to off-white powder | Lyophilised material forms a loose cake |
| Solubility | Freely soluble in water | Also dissolves in isotonic saline |
| Storage | -20 °C, desiccated | Aliquot solutions to avoid freeze–thaw cycling |
The compound is generally presented as a synthetic fragment of epithalamin, a pineal gland extract investigated in the former Soviet Union from the 1970s onward. Vladimir Khavinson and colleagues in Saint Petersburg developed short peptides modelled on such extracts, and epitalon became the most widely cited of those sequences. Most primary reports appeared in Russian-language journals or in proceedings with limited international circulation. Independent replication in laboratories outside that network remains sparse, and much repeated secondary material traces back to a small number of originating groups.
Laboratory work has examined effects on telomerase activity in cultured cells, on melatonin rhythms in animals, and on markers of oxidative stress. Some experiments report measurable changes while others show none, and the reported findings rest largely on small studies. The absence of large independent trials means the generality of these results is unresolved rather than settled. Review articles occasionally apply the label geroprotector, a term that reflects a research hypothesis about ageing rather than an established clinical finding.
Identity testing for epitalon relies on reversed-phase high-performance liquid chromatography for purity and mass spectrometry for mass confirmation. Because the sequence contains no tryptophan or tyrosine, ultraviolet detection at 280 nanometres is insensitive, so chromatographic methods usually monitor absorbance near 214 nanometres, where the peptide backbone absorbs. Electrospray ionisation or matrix-assisted laser desorption/ionisation then checks the intact mass against the expected value near 390 daltons. Peptide mapping or amino acid analysis after acid hydrolysis can supplement these measurements, although such confirmatory work is seldom reported on commercial certificates of analysis.
Stability of the tetrapeptide follows ordinary peptide chemistry rather than any unusual structural feature. The aspartate-glycine pair is prone to aspartimide formation under mildly basic or neutral conditions, and deamidation can follow, altering both mass and chromatographic retention. Dry lyophilised powder kept at or below minus twenty degrees Celsius is the usual handling recommendation, with repeated freeze-thaw cycles avoided. Once dissolved in neutral aqueous buffer, degradation proceeds over days to weeks depending on pH and temperature, while acidic conditions generally slow the aspartimide route. A formal stability-indicating study has not been published in the indexed literature.
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Reversed-phase liquid chromatography (RP-LC) is a mode of liquid chromatography in which non-polar stationary phase and polar mobile phases are used for the separation of organic compounds. In the reversed phase mode, the more hydrophobic sample components are retained in the system for longer. The vast majority of separations and analyses using high-performance liquid chromatography (HPLC) in recent years are done using the reversed phase mode. First developed for separating biomolecules, it is now a general technique with many stationary phases available for use in RP-LC, allowing great flexibility in the development of the separation methods. Some factors affect how the components are retained and separated in RP-LC:
Dermatological/integumental: oily skin, acne vulgaris, acne conglobata, seborrhea, stretch marks (due to rapid muscle enlargement), hypertrichosis (excessive body hair growth), androgenic alopecia (pattern hair loss; scalp baldness), fluid retention/edema. Reproductive/endocrine: libido changes, reversible infertility, hypogonadotropic hypogonadism. Male-specific: spontaneous erections, nocturnal emissions, priapism, erectile dysfunction, gynecomastia (mostly only with aromatizable and hence estrogenic AAS), oligospermia/azoospermia, testicular atrophy, intratesticular leiomyosarcoma, prostate hypertrophy, prostate cancer. Female-specific: masculinization, irreversible voice deepening, hirsutism (excessive facial/body hair growth), menstrual disturbances (e.g., anovulation, oligomenorrhea, amenorrhea, dysmenorrhea), clitoral enlargement, breast atrophy, uterine atrophy, teratogenicity (in female fetuses). Child-specific: premature epiphyseal closure and associated short stature, precocious puberty in boys, delayed puberty and contrasexual precocity in girls. Psychiatric/neurological: mood swings, irritability, aggression, violent behavior, impulsivity/recklessness, hypomania/mania, euphoria, depression, anxiety, dysphoria, suicidality, delusions, psychosis, withdrawal, dependence, neurotoxicity, cognitive impairment. Musculoskeletal: muscle hypertrophy, muscle strains, tendon ruptures, rhabdomyolysis.
=== Template-Directed Synthesis === Template-directed methods employ molecular templates to guide cage formation around a specific guest molecule. This approach can enhance selectivity and yield while providing control over cage size and shape. The template can either be removed post-synthesis or remain as a functional component of the final structure. The choice of template is crucial and depends on several factors including size compatibility, chemical affinity, and reversible binding capability. Common templates include metal ions, organic molecules, and solvent molecules. The template effect can operate through various mechanisms, such as geometric pre-organization of building blocks, electronic effects, or hydrogen bonding interactions. After cage formation, template removal strategies must be carefully considered to maintain the integrity of the cage structure.
Great consumption of fresh produce, especially cut fruits and vegetables. Wider distribution. Improved electronic reporting of outbreaks. An aging population more susceptible to foodborne illness. Unlike meat, which can be rid of bacteria through proper cooking, fresh produce is often meant to be consumed raw.
Sources: en.wikipedia.org
=== Production and fermentation === First, raw milk (either from cattle, goats or sheep) is mixed and pasteurized at 72 °C (162 °F) for 15 seconds. Then, acidification occurs: a starter culture, such as Streptococcus lactis, is added in order to change lactose to lactic acid, thus changing the acidity of the milk and turning it from liquid to solid. The next step is coagulation, where rennet, a mixture of rennin and other materials found in the stomach lining of a calf is added to solidify the milk further. Following this, thick curds are cut typically with a knife to encourage the release of liquid or whey. The smaller the curds are cut, the thicker and harder the resulting cheese will become. After the curds have been ladled into containers in order to be drained and formed into a full wheel of cheese, the Penicillium roqueforti inoculum is sprinkled on top of the curds along with Brevibacterium linens. Then, the curd granules are knit in molds to form cheese loaves with a relatively open texture. Next, whey drainage continues for 10–48 hours in which no pressure is applied, but the molds are inverted frequently to promote this process. Salt is then added to provide flavor as well as to act as a preservative so the cheese does not spoil through the process of brine salting or dry salting for 24–48 hours. The final step is ripening the cheese by aging it. When the cheese is freshly made, there is little to no blue cheese flavor development. Usually, a fermentation period of 60–90 days is needed before the flavor of the cheese is typical and acceptable for marketing.
== Foods and dietary supplements == As part of an overall diet, minimally processed foods provide a number of different naturally occurring vitamers. This is frequently in contrast to fortified foods and dietary supplements which generally provide vitamins as a single vitamer. Vitamin E, vitamin B6, and vitamin B9 are three examples.
variegation Variation or irregularity in a particular phenotype, especially a conspicuous visible trait such as color or pigmentation, occurring simultaneously in different parts of the same individual organism due to any of a variety of causes, such as X-inactivation, mitotic recombination, transposable element activity, position effects, or infection by pathogens.
Dissatisfied with the audio quality of their initial album recording sessions, the group re-recorded and remixed the material at Toronto Sound in late 1973 with the more experienced Terry Brown, which marked the beginning of a ten-year creative partnership. To help raise the $9,000 required to complete the album, Danniels sold his interest in his management company. Although Rutsey was originally tasked with writing the lyrics, he tore up his drafts immediately prior to the vocal sessions; Lee subsequently composed a new set of lyrics based on earlier versions to complete the album's final takes. Rutsey looked back on this incident with regret, and put it down to feeling "very confused about what I really wanted to do." Following a delay attributed to a provincial vinyl shortage, the self-titled debut, Rush, was released in March 1974. An initial pressing of 3,500 copies sold out quickly, and the album eventually reached No. 86 on the RPM Top Albums chart. While contemporary critics often critisised the album as derivative of Led Zeppelin, it gained traction in the United States after Donna Halper, music director and DJ at WMMS in Cleveland, had received a copy and added "Working Man" to the station's rotation. The song's blue-collar themes resonated with the city's industrial workforce, triggering a surge in demand for the Canadian import. To capitalise on this regional interest, Danniels secured a slot for the band opening for ZZ Top at Cleveland's Allen Theatre in June 1974.
Sources: en.wikipedia.org
It is a synthetic tetrapeptide. Its sequence was derived from research on peptide fractions of bovine pineal extract, and the intact AEDG sequence has not been demonstrated as an abundant free peptide in human tissue.
AEDG is the one-letter code for the four amino acids alanine, glutamate, aspartate and glycine in that order. The same molecule is written in three-letter form as Ala-Glu-Asp-Gly.
Identity is normally confirmed by mass spectrometry against the calculated mass of roughly 390.35 g/mol. Purity is then estimated by reversed-phase high-performance liquid chromatography with ultraviolet detection.
Mass spectrometry provides the identity check, because the observed mass is compared with the theoretical mass of the AEDG sequence. Chromatography separates and quantifies impurities but does not by itself prove which peptide is present. The two techniques are normally used together.