This is a working overview of Epitalon, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2026-04-19. Anything still debated is marked as such rather than presented as settled.
Regulatory status varies by country and is not harmonized. Epitalon is not an approved drug in major Western jurisdictions. In some countries it is sold as a research chemical, and in others it has appeared in products marketed for other categories. This inconsistent status means that purity, labeling accuracy, and documentation differ widely between suppliers, and verification of identity and purity through independent analysis is the usual way buyers assess a given lot.
Epitalon appears in the literature primarily through a small number of research groups, most of them associated with the St. Petersburg Institute of Bioregulation and Gerontology. Publications describe cell culture experiments, animal studies, and a limited number of small human studies. Independent replication outside this network is sparse. As a result, reviews of the topic usually separate descriptive reports of observed effects from the question of whether those effects generalize, and they note the difficulty of comparing studies that use different preparations and endpoints.
Analytical characterization of epitalon relies on standard peptide methods. Reverse-phase high-performance liquid chromatography is used to assess purity, and mass spectrometry confirms identity by checking the observed mass against the expected value near 390 daltons. Amino acid analysis can verify composition. Because the peptide is short and hydrophilic, it elutes early on many reverse-phase columns, so method development often requires ion-pairing reagents to achieve adequate retention and resolution from related impurities.
Laboratory-grade epitalon is typically supplied as a lyophilized powder. Purity is commonly assessed with reverse-phase high-performance liquid chromatography, often paired with mass spectrometry to confirm molecular identity. Amino acid analysis and peptide mapping can provide additional confirmation of sequence. Certificates of analysis for research materials frequently report purity above 95 percent, although the methods behind such figures vary between suppliers. The absence of a pharmacopeial monograph means that no single standardized assay defines the compound, so reported results depend on the analytical protocol chosen.
Storage recommendations center on limiting moisture, heat, and light. The dry powder is generally kept at minus 20 degrees Celsius, and some suppliers recommend minus 80 degrees for long-term archival. Once dissolved, solutions are usually aliquoted and frozen to avoid repeated freeze-thaw cycles, which can promote aggregation or degradation. Aqueous stability depends on pH and concentration, and buffered saline is often preferred over plain water for biological work. Stability data specific to epitalon remain limited, so general peptide-handling practices are applied by analogy rather than from product-specific validation.
Epitalon is a synthetic tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, abbreviated AEDG. Its molecular formula is C14H22N4O9 and its calculated monoisotopic mass is approximately 390.35 daltons. The compound does not occur naturally as a free peptide; it is produced by solid-phase peptide synthesis. Because it contains two acidic residues and no basic residues, the neutral form carries a net negative charge at physiological pH. This charge profile influences how the peptide behaves in solution and during chromatographic analysis.
| Property | Value | Notes |
|---|---|---|
| Purity assessment | RP-HPLC | Reported as percent area, often ≥95% |
| Identity confirmation | Mass spectrometry | Observed mass compared with ~390 Da |
| Typical storage temperature | -20 °C or below | Lyophilized powder, desiccated |
| Reconstitution solvent | Sterile water or buffer | Acidic residues aid dissolution |
| Common synonyms | AEDG; epithalon | Spelling varies in literature |
Storage practice centres on limiting moisture, oxygen, and repeated temperature cycling. Freeze-dried powder is generally held desiccated at minus twenty degrees Celsius or colder and protected from light. Reconstituted solutions are markedly less stable, and the aspartate-glycine junction is prone to succinimide formation at neutral to mildly alkaline pH. Portioning material into single-use aliquots reduces degradation compared with repeated freeze-thaw cycles. Stability data specific to this tetrapeptide remain scarce, so most handling guidance is extrapolated from general peptide chemistry rather than measured directly.
Documentation accompanying research peptides usually includes a certificate of analysis listing the batch number, purity figure, and test methods applied. Buyers comparing suppliers should check whether the reported purity refers to chromatographic area or to a mass-balance calculation, because the two are not equivalent. Counter-ion content, residual solvents, and water content are sometimes omitted from such certificates even though they affect the actual peptide mass present. Independent verification through a second laboratory is the most direct way to confirm that a supplied material matches its label.
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.
Epitalon is the common name for a synthetic tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, usually abbreviated AEDG. All four residues are proteinogenic amino acids, and the free peptide has a calculated mass near 390 grams per mole. Because the chain is short and carries no modifications, it is assembled readily by solid-phase synthesis and is distributed mainly as a freeze-dried solid for laboratory work. Catalogue listings use the spellings epitalon, epithalone, and simply AEDG, and the three refer to the same sequence.
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.
==== Diagnostic Statistical Manual assertion ==== DSM-IV lists General diagnostic criteria for a personality disorder guideline that "The pattern must not be better accounted for as a manifestation of another mental disorder, or to the direct physiological effects of a substance (e.g. drug or medication) or a general medical condition (e.g. head trauma).". As a result, AAS users may get misdiagnosed by a psychiatrist not told about their habit.
Pediatric asthma poses diagnostic challenges due to its variable presentation. Breath analysis could be a game-changer in pediatric allergic asthma management. By identifying unique exhaled metabolic signatures using SIRIUS, researchers developed an approach to diagnose children with allergic asthma. Thiacloprid is a first-generation, widely used, neonicotinoid insecticide. Its persistence in the environment and potential adverse effects on human health have raised significant concerns. Elucidating the impurity profile of pesticides is crucial for assessing their environmental impact and potential risks, and setting acceptable limits for impurities. Using SIRIUS, researchers demonstrated an approach for identifying structurally related impurities in pesticides. Under certain conditions, two bacterial species can thrive together in a dual-species biofilm. The cooperation between P. aeruginosa and S. aureus in cystic fibrosis leads to increased disease severity. Using SIRIUS, researchers identified a metabolite that could be related to the increased pathogenesis of this dual-species biofilm in cystic fibrosis. Our skin hosts a diverse community of microorganisms known as the skin microbiota. Using SIRIUS, researchers identified changes in the skin metabolome that are more pronounced than changes in the microbial composition, suggesting that even subtle shifts in microbial abundance can lead to significant effects on the skin.
== Chemistry == Omeprazole contains a tricoordinated sulfinyl sulfur in a pyramidal structure and therefore can exist as either the (S)- or (R)-enantiomers. Omeprazole is a racemate, an equal mixture of the two.
Soldiers were expected to carry their grain rations and cooking utensils in addition to their weaponry, with their backpacks potentially weighing as much as eighty pounds (36 kg). Without the hindrance of oxen and carts, this enabled Macedonian armies to move faster than their opponents. The grain provided to Macedonian soldiers would be wheat, barley, or millet, which were available throughout Asia and could be stored indefinitely when dried. The soldiers would use grinding mills carried by servants to turn the grain into flour, which could then be made into bread, biscuits, and porridge. They also ate various kinds of dried fruits such as dates and figs, which were readily available throughout much of Asia. Whenever possible, they would eat dried meat, salted fish, and shellfish. In ancient China, soldiers of the Han dynasty ate primarily millet and other grains such as wheat, rice, sorghum, etc. Grains could be eaten as a porridge, boiled, made into a bread or flatbread, smashed and fried in a manner similar to modern fried rice and fried noodles, etc. According to Zhao Chongguo, a military commander of the Han dynasty who served in the first century BC, a force of 10,281 men required 27,363 hu of grain and 308 hu of salt each month, requiring a convoy of 1,500 carts for transport. One hu is equivalent to 19.968 liters, meaning that each soldier would have required 51.9 liters of grain and 0.6 liters of salt per month. Another document at Juyan suggests 3.2 hu, or 63.8 liters, of grain.
Sources: en.wikipedia.org
The medical speciality that studies, diagnoses, and treats diseases caused by allergies is called allergology. An allergist is a physician specially trained to manage and treat allergies, asthma, and other allergic diseases. In the United States, physicians holding certification by the American Board of Allergy and Immunology (ABAI) have completed an accredited educational program and evaluation process, including a proctored examination to demonstrate knowledge, skills, and experience in patient care in allergy and immunology. Becoming an allergist/immunologist requires completion of at least nine years of training. After completing medical school and graduating with a medical degree, a physician will undergo three years of training in internal medicine (to become an internist) or pediatrics (to become a pediatrician). Once physicians have finished training in one of these specialties, they must pass the exam of either the American Board of Pediatrics (ABP), the American Osteopathic Board of Pediatrics (AOBP), the American Board of Internal Medicine (ABIM), or the American Osteopathic Board of Internal Medicine (AOBIM). Internists or pediatricians wishing to focus on the sub-specialty of allergy-immunology then complete at least an additional two years of study, called a fellowship, in an allergy/immunology training program. Allergists/immunologists listed as ABAI-certified have successfully passed the certifying ABAI examination following their fellowship. In the United Kingdom, allergy is a subspecialty of general medicine or pediatrics.
Individual transmembrane adenylyl cyclase isoforms have been linked to numerous physiological functions. Soluble adenylyl cyclase (sAC, AC10) has a critical role in sperm motility. Adenylyl cyclase has been implicated in memory formation, functioning as a coincidence detector. AC-IV was first reported in the bacterium Aeromonas hydrophila, and the structure of the AC-IV from Yersinia pestis has been reported. These are the smallest of the AC enzyme classes; the AC-IV (CyaB) from Yersinia is a dimer of 19 kDa subunits with no known regulatory components (PDB: 2FJT). AC-IV forms a superfamily with mammalian thiamine-triphosphatase called CYTH (CyaB, thiamine triphosphatase). These forms of AC have been reported in specific bacteria (Prevotella ruminicola O68902 and Rhizobium etli Q8KY20, respectively) and have not been extensively characterized. There are a few extra members (~400 in Pfam) known to be in class VI. Class VI enzymes possess a catalytic core similar to the one in Class III.
Isotope masses from: Wang, Meng; Huang, W.J.; Kondev, F.G.; Audi, G.; Naimi, S. (2021). "The AME 2020 atomic mass evaluation (II). Tables, graphs and references*". Chinese Physics C. 45 (3) 030003. doi:10.1088/1674-1137/abddaf. Isotopic compositions and standard atomic masses from: Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3) 030001. doi:10.1088/1674-1137/abddae. de Laeter, John Robert; Böhlke, John Karl; De Bièvre, Paul; Hidaka, Hiroshi; Peiser, H. Steffen; Rosman, Kevin J. R.; Taylor, Philip D. P. (2003). "Atomic weights of the elements. Review 2000 (IUPAC Technical Report)". Pure and Applied Chemistry. 75 (6): 683–800. doi:10.1351/pac200375060683. Wieser, Michael E. (2006). "Atomic weights of the elements 2005 (IUPAC Technical Report)". Pure and Applied Chemistry. 78 (11): 2051–2066. doi:10.1351/pac200678112051. "News & Notices: Standard Atomic Weights Revised". International Union of Pure and Applied Chemistry. 19 October 2005. Half-life, spin, and isomer data selected from the following sources. Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3) 030001. doi:10.1088/1674-1137/abddae. National Nuclear Data Center. "NuDat 3.0 database". Brookhaven National Laboratory. Holden, Norman E. (2004). "11. Table of the Isotopes". In Lide, David R. (ed.). CRC Handbook of Chemistry and Physics (85th ed.). Boca Raton, Florida: CRC Press. ISBN 978-0-8493-0485-9.
Sources: en.wikipedia.org
Manufacturing facilities must maintain a clean and hygienic manufacturing area. Manufacturing facilities must maintain controlled environmental conditions in order to prevent cross-contamination from adulterants and allergens that may render the product unsafe for human consumption or use. Manufacturing processes must be clearly defined and controlled. All critical processes are validated to ensure consistency and compliance with specifications. Manufacturing processes must be controlled, and any changes to the process must be evaluated. Changes that affect the quality of the drug are validated as necessary. Instructions and procedures must be written in clear and unambiguous language using good documentation practices. Operators must be trained to carry out and document procedures. Records must be made, manually or electronically, during manufacture that demonstrate that all the steps required by the defined procedures and instructions were in fact taken and that the quantity and quality of the food or drug was as expected. Deviations must be investigated and documented. Records of manufacture (including distribution) that enable the complete history of a batch to be traced must be retained in a comprehensible and accessible form. Any distribution of products must minimize any risk to their quality. A system must be in place for recalling any batch from sale or supply.
== External links == CID 16132316 from PubChem – β-endorphin CID 3081525 from PubChem – β-endorphin (1-9) CID 133304 from PubChem – β-endorphin (2-9) β-endorphin at the U.S. National Library of Medicine Medical Subject Headings (MeSH)
== Cost == An effective vaccine for COVID‑19 could save trillions of dollars in global economic impact, according to economists Arnab Acharya and Sanjay Reddy who advocate suspending patent protections for vaccines temporarily and compensating the affected companies. Any price tag in the billions would therefore look small in comparison. In early stages of the pandemic, it was not known if it would be possible to create a safe, reliable and affordable vaccine for this virus, and it was not known exactly how much the vaccine development could cost. Even with several vaccines on the market, the antigenicity changes in new variants of the virus mean that the billions of dollars could still be invested without success. Before an effective vaccine was developed, it was clear that billions of doses would need to be manufactured and distributed worldwide. In April 2020, the Gates Foundation estimated that manufacturing and distribution could cost as much as US$25 billion. Gates also admitted "Ideally, there would be global agreement about who should get the vaccine first, but given how many competing interests there are, this is unlikely to happen". From Phase I clinical trials, 84–90% of vaccine candidates fail to make it to final approval during development, and from Phase III, 25.7% fail – the investment by a manufacturer in a vaccine candidate may exceed US$1 billion and end with millions of useless doses given advanced manufacturing agreements. In the case of the Oxford-AstraZeneca COVID-19 vaccine, 97% of this came from public financing.
Sources: en.wikipedia.org
Identity is normally confirmed by mass spectrometry, which checks the measured mass against the expected value near 390 daltons. Reverse-phase high-performance liquid chromatography is used alongside it to assess purity. Amino acid analysis can provide additional composition data.
The powder is generally kept refrigerated or frozen, protected from light and moisture. Vials should reach room temperature before opening to prevent condensation. Reconstituted solutions are usually stored cold and used within a limited window because dilute solutions can degrade or support microbial growth.
Epitalon is not an approved drug in major Western regulatory jurisdictions. Its legal status differs between countries, and it is often distributed as a research chemical. This means product documentation and purity vary considerably between suppliers.
Epitalon is a synthetic tetrapeptide built from four amino acids: alanine, glutamate, aspartate, and glycine. It is not extracted from a natural source but made in the laboratory by chemical synthesis. Its short length makes it relatively straightforward to produce at high purity.