If you have been reading about lyophilised powder and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2025-08-16. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
Freeze-dried epitalon is normally kept at minus twenty degrees Celsius in a sealed, desiccated container, protected from light. Short excursions at ambient temperature during shipping are generally tolerated, but repeated warming and cooling cycles encourage moisture uptake, which shortens shelf life. Once dissolved, the peptide is far less stable than the solid: aqueous solutions are subject to hydrolysis and to deamidation at the aspartate and glutamate residues. Working solutions are therefore held refrigerated and used within days, and repeated freezing and thawing of the same vial is best avoided.
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.
Chemically, the molecule consists of four amino acid residues joined by three peptide bonds, with a free N-terminal amino group and a free C-terminal carboxyl group. Its molecular formula is C14H22N4O9, and its monoisotopic mass is approximately 390 daltons. The acidic glutamate and aspartate side chains give the peptide a net negative charge near neutral pH, a property that shapes its chromatographic behaviour and solubility profile. No disulfide bridges or other post-translational modifications are present, so the primary sequence alone defines the structure.
Most experimental work has been carried out in cell culture and animal models. Several reports describe changes in telomerase activity and proliferation in cultured cells, while rodent studies have examined lifespan, melatonin rhythm and reproductive endpoints. Human data remain limited, and much of the published clinical material consists of small trials with incomplete reporting of methods and controls. Whether the cell and animal findings translate into measurable effects in people is an open question, and the mechanistic basis of the reported telomerase changes is not fully established.
| Property | Value | Notes |
|---|---|---|
| Storage temperature, solid | Approximately -20 C | Sealed, desiccated, protected from light |
| Typical identity method | Electrospray mass spectrometry | Protonated ion expected near 391 |
| Typical purity method | Reversed-phase HPLC | Ultraviolet detection near 214 nm |
| Common synonyms | Epithalon, epithalone, AEDG | Spelling variants appear in supplier catalogues |
| Solution stability | Days at 2-8 C | Hydrolysis and deamidation limit shelf life |
Verification of research-grade material involves comparing a supplier chromatogram against an in-house reference, checking the observed mass against the calculated value, and where possible confirming residue order by tandem mass spectrometry or enzymatic peptide mapping. Purity claims should be read alongside the method used to obtain them, because detection wavelength and integration settings alter the result. Batch-specific data, rather than a generic grade statement, is the informative part of a certificate.
Identity and purity of epitalon samples are normally established by reversed-phase high-performance liquid chromatography with ultraviolet detection near 214 nanometres, combined with mass spectrometry. The mass spectrum confirms the expected molecular ion and can reveal truncated or oxidised by-products. Amino acid analysis after acid hydrolysis verifies that the four residues are present in the expected ratio. Certificates typically report a purity figure taken from chromatographic peak area, expressed as a percentage of total integrated signal.
Lyophilised epitalon is generally held at minus twenty degrees Celsius in a sealed container kept dry and dark. Cooler conditions are sometimes recommended for long-term archives. The solid takes up moisture readily enough that repeated opening of a vial introduces water, so dividing a batch into smaller portions before storage lowers degradation risk. Aqueous solutions are less durable than the dry powder and are usually prepared shortly before use, then kept cold and shielded from light to slow hydrolysis and oxidation.
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.
It has been estimated that only 10.33% of all municipal solid waste (MSW), which makes up to 30.3% of the total waste, is recycled into new products globally. However, depending on the level of packaging and the materials that are being used during their manufacturing, the end-of-life of a package may differ completely. Despite the fact that a recycling process is usually the desired path, lots of complications may lead to less sustainable destines.
India had a large, consumption-driven middle class and witnessed a communications boom. However, India's economic growth has been accompanied by widening income gaps, gender inequality, and degradation of the environment. In recent years, India has witnessed a shift toward majoritarianism and Hindu nationalism, which has led to democratic erosion.
==== Approved topical medicine ==== In the European Union, a prescription gel containing birch bark extract (commercial name Episalvan, betulae cortex dry extract (5–10 : 1); extraction solvent: n-heptane 95% (w/w)) was approved in 2016 for the topical treatment of minor skin wounds in adults. Although its mechanism of action in helping to heal injured skin is not fully understood, birch bark extract appears to stimulate the growth of keratinocytes which then fill the wound.
Folic acid: Low plasma concentrations of folic acid were found to be associated with high plasma homocysteine concentrations. In clinical trials, homocysteine concentrations were effectively reduced within 4 to 6 weeks of oral supplementation of folic acid. Moreover, since the activity of endothelial NO synthase enzyme might be potentially elevated by folate, folate supplementation might be capable of restoring the availability of NO in endothelium, therefore, improving endothelial function and reducing the risk for atherosclerosis. van Etten et al., found that a single dose of folic acid might help in reducing the risk of vascular complications and enhancing endothelial function in adults with type 2 diabetes by improving nitric oxide status.
== History == Cinoxacin is one of the original quinolone drugs, which were introduced in the 1970s. Commonly referred to as the first generation quinolones. This first generation also included other quinolone drugs such as pipemidic acid, and oxolinic acid, but this first generation proved to be only marginal improvements over nalidixic acid. Cinoxacin is similar chemically (and in antimicrobial activity) to oxolinic acid and nalidixic acid. Relative to nalidixic acid, cinoxacin was found to have a slightly greater inhibitory and bactericidal activity. Cinoxacin was patented in 1972 and assigned to Eli Lilly. Eli Lilly obtained approval from the FDA to market cinoxacin in the United States as Cinobac on June 13, 1980. Prior to this cinobac was marketed in the U.K. and Switzerland in 1979. Oclassen Pharmaceuticals (Oclassen Dermatologics) commenced sales of Cinobac in the United States and Canada back in September 1992, under an agreement with Eli Lilly which granted Oclassen exclusive United States and Canadian distribution rights. Oclassen promoted Cinobac primarily to urologists for the outpatient treatment of initial and recurrent urinary tract infections and prophylaxis. Oclassen Pharmaceuticals was a privately held pharmaceutical company founded in 1985 until acquired by Watson Pharmaceuticals, Inc., in 1997. Watson Pharmaceuticals, Inc., (also incorporated in 1985), having acquired Oclassen Pharmaceuticals (Oclassen Dermatologics) also acquired the marketing rights contained within the agreement with Eli Lilly to market Cinobac.
Sources: en.wikipedia.org
for the 2D (linear) ion trap were also given in literature. There are at least two postulates about the nature of the DC component. The first, of which has been attributed to Ding, assumes for the DIT that the DC component, U depends on not only the mid-level of the AC voltages, V1and V2, but also the duty cycle, d of the waveform:
=== Renaming === The laboratory was renamed Lawrence Livermore Laboratory (LLL) in 1971. On October 1, 2007 Lawrence Livermore National Security, LLC (LLNS) assumed management of LLNL from the University of California, which had exclusively managed and operated the Laboratory since its inception 55 years before. The laboratory was honored in 2012 by having the synthetic chemical element livermorium named after it. The LLNS takeover of the laboratory has been controversial. In May 2013, an Alameda County jury awarded over $2.7 million to five former laboratory employees who were among 430 employees LLNS laid off during 2008. The jury found that LLNS breached a contractual obligation to terminate the employees only for "reasonable cause." The five plaintiffs also have pending age discrimination claims against LLNS, which will be heard by a different jury in a separate trial. There are 125 co-plaintiffs awaiting trial on similar claims against LLNS. The May 2008 layoff was the first layoff at the laboratory in nearly 40 years. On March 14, 2011, the City of Livermore officially expanded the city's boundaries to annex LLNL and move it within the city limits. The unanimous vote by the Livermore city council expanded Livermore's southeastern boundaries to cover 15 land parcels covering 1,057 acres (4.28 km2) that comprise the LLNL site. The site was formerly an unincorporated area of Alameda County. The LLNL campus continues to be owned by the federal government.
Vampire: The Masquerade – Bloodlines takes place in four areas of 21st-century Los Angeles: Santa Monica, Hollywood, Downtown Los Angeles, and Chinatown. Set in the World of Darkness, the game depicts a world in which vampires, werewolves, demons, and other creatures shape human history. A code binds the vampires to maintain their secrecy (forbidding the use of vampiric abilities in front of humans) and avoid unnecessary killing (to preserve the vampire's last shreds of humanity). The vampires are divided into seven clans of the Camarilla, the vampire government, with distinctive traits and abilities. The Toreadors are the closest to humanity, with a passion for culture; the Ventrue are noble, powerful leaders; the Brujah are idealists who excel at fighting; the Malkavians are cursed with insanity or blessed with insight; the Gangrel are loners, in sync with their animalistic nature; the secretive, untrustworthy Tremere wield blood magic; and the monstrous Nosferatu are condemned to a life in the shadows to avoid humanity. The clans are loosely united by their belief in the Camarilla's goals and opposition to the Sabbat: vampires who revel in their nature, embracing the beast within. The Anarch Movement is a faction of idealistic vampires opposed to the Camarilla's political structure, believing that all vampires should share power. The main character of Bloodlines, whom the player controls, is an unnamed fledgling vampire who is transformed at the start of the game and belongs to one of the clans.
=== Treatment of type 2 diabetes === They are widely used as antidiabetic drugs in the management of diabetes mellitus type 2. They act by increasing secretion of insulin from the beta cells in the pancreas. Sulfonylureas are ineffective where there is absolute deficiency of insulin production such as in type 1 diabetes or post-pancreatectomy. Sulfonylureas can be used to treat some types of neonatal diabetes. Historically, people with hyperglycemia and low blood insulin levels were diagnosed with type 1 diabetes by default, but it has been found that patients who receive this diagnosis before 6 months of age are often candidates for receiving sulfonylureas rather than insulin throughout life. A 2011 Cochrane systematic review evaluated the effects on treatment of Latent Autoimmune Diabetes in Adults (LADA) and found that Sulfonylureas did not improve metabolic control of glucose at 3 and 12 months, even worsening HbA1c levels in some cases, when compared to insulin. The same review did not find improvement of fasting C-peptide following treatment with sulfonylurea. Still, it is important to highlight that the studies available to be included in this review presented considerable flaws in quality and design. While prior sulfonylureas were associated with worse outcomes, newer agents do not appear to increase the risk of death, heart attacks, or strokes.
Most DNA sequencing techniques produce short fragments of sequence that need to be assembled to obtain complete gene or genome sequences. The shotgun sequencing technique (used by The Institute for Genomic Research (TIGR) to sequence the first bacterial genome, Haemophilus influenzae) generates the sequences of many thousands of small DNA fragments (ranging from 35 to 900 nucleotides long, depending on the sequencing technology). The ends of these fragments overlap and, when aligned properly by a genome assembly program, can be used to reconstruct the complete genome. Shotgun sequencing yields sequence data quickly, but the task of assembling the fragments can be quite complicated for larger genomes. For a genome as large as the human genome, it may take many days of CPU time on large-memory, multiprocessor computers to assemble the fragments, and the resulting assembly usually contains numerous gaps that must be filled in later. Shotgun sequencing is the method of choice for virtually all genomes sequenced (rather than chain-termination or chemical degradation methods), and genome assembly algorithms are a critical area of bioinformatics research.
Sources: en.wikipedia.org
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.
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.
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.
It is a synthetic tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, often abbreviated AEDG. The molecule is linear and contains no modified residues, so it is fully described by its sequence.