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Storage, Assay, And Regulatory Framework — Reference Sheet

By Editorial Desk · published 2025-09-20 · last reviewed 2025-10-30 · Guide

The short version of Epithalamin fits in a sentence. The long version — which is the one that helps — is below.

Reviewed 2025-10-30. Anything still debated is marked as such rather than presented as settled.

Storage, Assay, and Regulatory Framework

Identity and purity are checked by reversed-phase high-performance liquid chromatography, usually with ultraviolet detection near 214 nanometres, where the peptide bond absorbs. Mass spectrometry confirms the expected mass and reveals whether truncation products or adducts are present. Acid hydrolysis followed by amino acid analysis gives the residue ratio, which should approximate one alanine, one glutamate, one aspartate and one glycine. Counter-ions such as acetate or trifluoroacetate remain in the dried product and lower net peptide content, so a stated purity figure on a label does not by itself describe how much peptide a vial holds.

Regulatory treatment differs by country. No formulation of epitalon holds a marketing authorisation as a medicine in the United States or the European Union, where material sold for laboratory use is handled as a research chemical and is not intended for human consumption. In Russia, several short peptide preparations from the same institute's peptide series are registered medicinal products, and epitalon appears in that national context. Elsewhere it is frequently offered as a cosmetic ingredient, a category with lighter requirements. Advertising claims about longevity or disease prevention are restricted in most jurisdictions, which limits how sellers describe the compound.

Chemical Identity and Research Background

In its supplied form epitalon is a white to off-white powder, usually lyophilized and often hygroscopic. It dissolves readily in water and in aqueous buffers, and it is commonly handled as the acetate or trifluoroacetate salt to improve stability during purification and drying. The amide backbone is labile in aqueous media, so solutions are less durable than the dry solid. Handling notes in the chemical literature therefore emphasize keeping the powder dry, cool and shielded from light until it is dissolved.

Epitalon is a synthetic tetrapeptide whose sequence is alanine-glutamate-aspartate-glycine, written in single-letter code as AEDG. The four residues are joined by three peptide bonds, giving a linear backbone with no branching and no disulfide bridges. Its calculated molecular mass for the free form is approximately 390.3 daltons, a figure that rises when the compound is supplied as an acetate or trifluoroacetate salt. Because the chain is short, the molecule is defined entirely by its residue order rather than by any folded three-dimensional structure.

The compound is described in the literature as a derivative of epithalamin, a preparation obtained from bovine pineal tissue. Work on this peptide family was carried out mainly by a research group in Saint Petersburg beginning in the 1980s, and the substance was later registered for clinical use in Russia under the name Epitalon. Outside that region it is generally treated as a research chemical rather than an approved medicine. Statements about its biological activity rest on a relatively small number of studies, and independent replication remains limited.

Epitalon at a glance

PropertyValueNotes
Storage temperature, solidApproximately -20 CSealed, desiccated, protected from light
Typical identity methodElectrospray mass spectrometryProtonated ion expected near 391
Typical purity methodReversed-phase HPLCUltraviolet detection near 214 nm
Common synonymsEpithalon, epithalone, AEDGSpelling variants appear in supplier catalogues
Solution stabilityDays at 2-8 CHydrolysis and deamidation limit shelf life

Analytical Methods And Handling

Purity assessment of peptide reagents normally relies on reversed-phase high-performance liquid chromatography. A gradient of acetonitrile in water with trifluoroacetic acid, paired with a C18 stationary phase, separates the target tetrapeptide from truncated sequences and deletion analogues. Detection at 214 nanometres exploits absorbance of the peptide backbone, since the molecule contains no aromatic residue. Results are expressed as a percentage of total peak area. Values above ninety-five percent are typical for research-grade material, although reporting conventions vary between suppliers.

Identity confirmation uses mass spectrometry, usually electrospray ionisation in positive mode or matrix-assisted laser desorption. The protonated free peptide produces a signal near three hundred and ninety-one daltons, while salt adducts shift that value slightly. Tandem mass spectrometry or amino acid analysis supplies sequence-level confirmation, which a single mass measurement cannot. Peptides containing aspartate can cyclise into succinimide intermediates that hydrolyse to isoaspartate isomers of identical mass. Because those isomers are difficult to separate chromatographically, identity and purity results carry more weight when interpreted together.

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Background and Chemical Identity

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.

Epitalon is a synthetic linear tetrapeptide with the sequence alanine–glutamate–aspartate–glycine, abbreviated AEDG. Its molecular formula is C14H22N4O9 and the calculated mass is approximately 390.35 g/mol. The compound is made by solid-phase peptide synthesis rather than extracted from tissue, although early work described it as a short fragment of a peptide fraction obtained from bovine pineal extract. In the research literature the spelling epitalon and the variant epithalone both appear, while AEDG is the standard code used in peptide nomenclature.

Supporting material

=== Amateur === The North Carolina Tigers compete as an Australian rules football club in the United States Australian Football League, in the Eastern Australian Football League. The Raleigh Cú Chulainn Gaelic Athletic Association competes in men's and women's Gaelic Football, Hurling, and Camogie. It is a member in the Southeast Division of the United States Gaelic Athletic Association and the Gaelic Athletic Association based in Ireland. The Raleigh GAA won the Junior B Men's Football national championship in 2014. The Raleigh GAA and the North Carolina Tigers Australian rules football clubs compete in the annual Oak City Cup where both clubs compete under the compromise football rules adapted by Ireland and Australia for international competition. Raleigh is also home to one of the Cheer Extreme All Stars gyms. In 2009 and again in 2010, Cheer Extreme Raleigh's Small Senior Level 5 Team were silver medalists at the Cheerleading Worlds Competition in Orlando, Florida, and in 2012 they received the bronze medal. Raleigh is also home to one of the Southeast's premier Hardcourt Bike Polo clubs. Because of the area's many billiards rooms, Raleigh is home to one of the largest amateur league franchises for playing pool, the Raleigh, Durham, Chapel Hill American Poolplayers Association. There are leagues available in formats for players of any skill level.

Note: + = Positive, - =Negative P. aeruginosa is a Gram-negative, aerobic (and at times facultatively anaerobic), rod-shaped bacterium with unipolar motility. It has been identified as an opportunistic pathogen of both humans and plants. P. aeruginosa is the type species of the genus Pseudomonas. Identification of P. aeruginosa can be complicated by the fact individual isolates often lack motility. The colony morphology itself also displays several varieties. The main two types are large, smooth, with a flat edge and elevated center and small, rough, and convex. A third type, mucoid, can also be found. The large colony can typically be found in clinal settings while the small is found in nature. The third, however, is present in biological settings and has been found in respiratory and in the urinary tract. Furthermore, mutations in the gene lasR drastically alter colony morphology and typically lead to failure to hydrolyze gelatin or hemolyze. In certain conditions, P. aeruginosa can secrete a variety of pigments, including pyocyanin (blue), pyoverdine (yellow and fluorescent), pyorubin (red), and pyomelanin (brown). These can be used to identify the organism.

Quick fixes have included applying chewed tobacco from cigarettes, cigars, or pipes. Making cuts around the puncture or sucking out the venom had been thought helpful in the past, but this course of treatment is now strongly discouraged, due to the risk of self-envenomation through knife cuts or cuts in the mouth (suction cups from snake bite kits can be used, but suctioning seldom provides any measurable benefit).

Secretin is a hormone that regulates water homeostasis throughout the body and influences the environment of the duodenum by regulating secretions in the stomach, pancreas, and liver. It is a peptide hormone produced in the S cells of the duodenum, which are located in the intestinal glands. In humans, the secretin peptide is encoded by the SCT gene. Secretin helps regulate the pH of the duodenum by inhibiting the secretion of gastric acid from the parietal cells of the stomach and stimulating the production of bicarbonate from the ductal cells of the pancreas. It also stimulates the secretion of bicarbonate and water by cholangiocytes in the bile duct, protecting it from bile acids by controlling the pH and promoting the flow in the duct. Meanwhile, in concert with secretin's actions, the other main hormone simultaneously issued by the duodenum, cholecystokinin (CCK), stimulates the gallbladder to contract, delivering its stored bile. Prosecretin is a precursor to secretin, which is present in digestion. Secretin is stored in this unusable form, and is activated by gastric acid. This indirectly results in the neutralisation of duodenal pH, thus ensuring no damage is done to the small intestine by the aforementioned acid. In 2007, secretin was discovered to play a role in osmoregulation by acting on the hypothalamus, pituitary gland, and kidney.

In one well-known 1974 case series, 8 people accidentally insufflated two "lines" of nearly pure LSD powder that they thought were cocaine. The exact doses of LSD were unknown, but were considered to be massive. For context, a typical "line" of cocaine for insufflation is 50 to 100 mg. The individuals reported to the hospital within 10 to 15 minutes, with five of them comatose, three requiring intubation and mechanical ventilation, and the conscious individuals experiencing severe hallucinogenic effects, among other toxic symptoms. All of them completely recovered within 12 hours and there were no deaths. A subsequent 2020 case similarly involved accidental insufflation of a confirmed 55 mg dose of LSD instead of cocaine, which was without adverse health consequences. In other reports, a 5 mg overdose of LSD produced severe nausea and vomiting along with severe behavioral disturbances, while a 10 mg overdose was also non-fatal. Despite acting as non-selective serotonin receptor agonists, major psychedelics like LSD and psilocybin do not cause serotonin syndrome even with extreme overdose. This is thought to be because they act as partial agonists of serotonin receptors like the serotonin 5-HT2A receptor relative to serotonin itself. Conversely, NBOMe psychedelics like 25I-NBOMe are more efficacious and have been uniquely associated with serotonin syndrome-like toxicity. A 2018 retrospective analysis of 3,554 LSD-only exposures reported to poison control centers in the United States between 2000 and 2016 found that serious toxicity was infrequent.

Sources: en.wikipedia.org

Notes from published material

The Census Bureau's 2006–2010 American Community Survey showed that (in 2010 inflation-adjusted dollars) median household income was $105,625 (with a margin of error of +/− $14,945) and the median family income was $128,382 (+/− $16,732). Males had a median income of $95,795 (+/− $24,665) versus $72,188 (+/− $16,155) for females. The per capita income for the borough was $56,485 (+/− $6,202). About 2.4% of families and 4.0% of the population were below the poverty line, including 1.8% of those under age 18 and 9.4% of those age 65 or over.

Herbivores have developed a diverse range of physical structures to facilitate the consumption of plant material. To break up intact plant tissues, mammals have developed teeth structures that reflect their feeding preferences. For instance, frugivores (animals that feed primarily on fruit) and herbivores that feed on soft foliage have low-crowned teeth specialized for grinding foliage and seeds. Grazing animals that tend to eat hard, silica-rich grasses, have high-crowned teeth, which are capable of grinding tough plant tissues and do not wear down as quickly as low-crowned teeth. Most carnivorous mammals have carnassial teeth (of varying length depending on diet), long canines and similar tooth replacement patterns. The stomach of even-toed ungulates (Artiodactyla) is divided into four sections: the rumen, the reticulum, the omasum and the abomasum (only ruminants have a rumen). After the plant material is consumed, it is mixed with saliva in the rumen and reticulum and separates into solid and liquid material. The solids lump together to form a bolus (or cud), and is regurgitated. When the bolus enters the mouth, the fluid is squeezed out with the tongue and swallowed again. Ingested food passes to the rumen and reticulum where cellulolytic microbes (bacteria, protozoa and fungi) produce cellulase, which is needed to break down the cellulose in plants. Perissodactyls, in contrast to the ruminants, store digested food that has left the stomach in an enlarged cecum, where it is fermented by bacteria.

=== Broadcasting === While attending college in Drury, Barker worked his first media job at KTTS-FM Radio in Springfield. He and his wife left Springfield and moved to Lake Worth Beach, Florida, and Barker was news editor and announcer at nearby WWPG 1340 AM in Palm Beach (now WPBR in Lantana). In 1950, he moved to California to advance his broadcasting career. Barker was given his own radio show, The Bob Barker Show, which ran for the next six years from Burbank. He was hosting an audience-participation radio show on KHJ (AM) in Los Angeles when game show producer Ralph Edwards, who was looking for a new host to replace Jack Bailey on the daytime-television version of his long-running show, Truth or Consequences, happened to be listening and liked Barker's voice and style.

Larter next appeared as Zerelda Mimms in the western comedy American Outlaws. Directed by Les Mayfield and co-starring Irish actor Colin Farrell and Scott Caan, the film was poorly received by critics and at the box office making only $13 million. She also starred in Kevin Smith's Jay and Silent Bob Strike Back. In 2001, Larter appeared on the cover of Maxim magazine and performed in the stage play The Vagina Monologues in Manhattan, New York. In Spring 2002, Larter moved from Los Angeles to New York. "I was too young and impressionable to handle the pressures of L.A." Larter later recalled in an interview: "I'm a woman now. I am no longer the little girl who could be easily influenced (back then)." While in New York City, she made herself available for independent film projects and being in theater. Larter's first project in New York City was to reprise her role as Clear Rivers in the sequel to Final Destination entitled Final Destination 2. In an interview with IGN, Larter said, "When New Line asked me to come back, I thought it was great. They showed me the script and let me have some input, and it was really terrific." The film made $90 million worldwide with a mixed critical reception. In 2004, Larter served as an associate producer of and starred in the thriller Three Way.

=== Persian period === In 537–520 BCE, Zerubbabel became Yehud's governor and started work on the Second Temple, which was stopped. In 520–516 BCE, Haggai and Zechariah goaded the Judahites to resume work on the Temple. Upon completion, Joshua became its high priest. In 458–433 BCE, Ezra and Nehemiah led another group of Judahites to Yehud, with Artaxerxes's permission. Nehemiah rebuilt the temple after some unspecified disaster and removed foreign influence from the Judahite community. That said, some Judahites elected to stay in Persia, where they almost faced annihilation. This period is covered by the entirety of the Book of Ezra, Book of Nehemiah, the Book of Esther, the Book of Haggai, the Book of Zechariah, and the Book of Malachi.

Sources: en.wikipedia.org

Background from the literature

Much of the Gulf states' food is imported – for example, over 90 per cent in Qatar. These factors have led to fears of food insecurity not only in Gulf states, but around the world. As of 28 March, analysts fear that another hard oil crisis is unfolding that is expected to be very decisive to the global economy. Oil prices increased on September 13 due to market stability after recent declines. Investors are awaiting potential U.S.-Iran talks at the UN General Assembly. Analysts believe the price rise may result from traders adjusting their positions rather than a change in market trends.

=== Censorship === Twitter Blue Checkmarks have been removed or suspended from verified accounts as a form of censorship. Laura Loomer, a political activist, conspiracy theorist and Internet personality, was opposed to H-1B visas and then lost her blue checkmark on 27 December 2024. Gavin Mario Wax, ConservativePAC, and Owen Shroyer also affected.

==== Zebrafish ==== Being model organisms, zebrafish myomeres have been extensively studied. The tail-bending maneuver generated by myomeres in zebrafish requires innervation from motor neurons for both the hypaxial and epaxial muscle regions. It has been found that timing/intensity of neurons firing in these two regions varies, respectively. This process is mediated by a circuit that controls motor neuron activation during swimming behaviors, which, in turn, affects force generation. Similar to this idea, one study found that hypaxial and epaxial myomere activation did not always correlate with myomeric fibers closer to the horizontal septum itself.

=== Psychological === Early theories of the cause of anorexia linked it to childhood sexual abuse or dysfunctional families; evidence is conflicting, and well-designed research is needed. The fear of food is known as sitiophobia or cibophobia, and is part of the differential diagnosis. Other psychological causes of anorexia include low self-esteem, feeling as if there is lack of control, depression, anxiety, and loneliness. People with anorexia are, in general, highly perfectionistic and most have obsessive compulsive personality traits which may facilitate sticking to a restricted diet. It has been suggested that patients with anorexia are rigid in their thought patterns, and place a high level of importance upon being thin. In the context of anorexia nervosa, this cognitive rigidity refers to the diminished ability to adapt one's behavioral approaches in response to changing circumstances. This weaker cognitive flexibility is a result of neurobiological factors, such as structural differences in prefrontal cortex connectivity, that contribute to the persistence of anorexic behaviors. Although the prevalence rates vary greatly, between 37% and 100%, there appears to be an association between traumatic events and eating disorder diagnosis. Approximately 72% of individuals with anorexia report experiencing a traumatic event prior to the onset of eating disorder symptoms, with binge-purge subtype reporting the highest rates.

Sources: en.wikipedia.org

Frequently asked questions

How should epitalon be stored?

The solid is kept cold, dry and dark, typically at minus twenty degrees Celsius, in a sealed container with desiccant. Dissolved material is kept refrigerated and used promptly. Freezing and thawing a solution repeatedly is avoided because it accelerates degradation.

How is the purity of a sample verified?

Reversed-phase chromatography with ultraviolet detection gives a purity percentage, while mass spectrometry confirms identity. Amino acid analysis checks the residue composition. Buyers typically request a certificate of analysis showing these measurements for the specific lot.

Is epitalon a licensed medicine?

It is not authorised as a medicine in the United States or the European Union. Material is sold there as a research chemical or cosmetic ingredient. Some related short peptides are registered drugs in Russia, which is a distinct national situation rather than a general approval.

Which amino acids make up epitalon?

The peptide contains four residues in the order alanine, glutamate, aspartate and glycine, abbreviated AEDG. The chain is linear and held together by three peptide bonds. Its calculated mass for the uncharged free form is about 390.3 daltons.

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