Everything below concerns tetrapeptide. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-08-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
Epitalon is a synthetic tetrapeptide with the amino acid sequence alanine-glutamate-aspartate-glycine, abbreviated Ala-Glu-Asp-Gly or AEDG. It was developed by the Russian researcher Vladimir Khavinson and colleagues during work on peptide bioregulators derived from the pineal gland. The compound is short enough to be produced by standard solid-phase peptide synthesis and is typically handled as a lyophilized white powder. Its small size distinguishes it from larger pineal peptides such as epithalamin, a complex extract from which the tetrapeptide was conceptually derived.
The four residues give epitalon a molecular formula of C14H22N4O9 and a molecular weight near 390.35 daltons. The presence of two acidic residues, glutamate and aspartate, makes the free peptide strongly acidic, while the alanine and glycine ends provide neutral, nonpolar character. This combination produces a molecule with substantial water solubility. Because there are no cysteine, methionine, or tryptophan residues, the peptide lacks the most common oxidation-sensitive side chains, which simplifies handling compared with many longer peptides.
The proposed relationship between epitalon and pineal function is a central part of its background. Khavinson's group reported that short peptides corresponding to regions of larger pineal proteins could influence gene expression in cells. Epitalon was framed as a synthetic analogue of an active fragment rather than a direct isolation product. Whether the tetrapeptide reproduces the effects of the parent extract is an open question, because comparative studies are limited and the parent extract itself is not a single defined substance.
（TG:@pojiaai）Epitalon is a synthetic linear tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, abbreviated AEDG. It emerged from work on epithalamin, a peptide fraction prepared from bovine pineal tissue, and was designed as a short, chemically defined analogue of that extract. Early publications came mainly from Russian laboratories studying pineal peptides and aging-related endpoints. The compound appears in the literature under several spellings, including epithalon and epithalone, which complicates systematic searching. Its small size makes solid-phase assembly and routine analytical characterization straightforward.
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 |
|---|---|---|
| Amino acid sequence | Ala-Glu-Asp-Gly | Tetrapeptide, often abbreviated AEDG |
| Molecular formula | C14H22N4O9 | Free peptide, unmodified termini |
| Molecular weight | ~390.35 Da | Calculated for the free acid form |
| Appearance | White to off-white powder | Typical lyophilized product form |
| Solubility class | Freely soluble in water | Two acidic residues dominate ionic character |
== Interactions == Lixisenatide and other GLP-1 receptor agonist slow emptying of stomach contents, which may affect the absorption of orally administered medications. For effective use, oral contraceptives should be taken 1 hour before or 11 hours after taking lixisenatide-containing products. Acetaminophen and antibiotics are among other drugs that are affected by this action of lixisenatide.
Freeze-dried nanocellulose aerogels used in sanitary napkins, tampons, diapers or as wound dressing The use of nanocellulose as a composite coating agent in cosmetics e.g. for hair, eyelashes, eyebrows or nails A dry solid nanocellulose composition in the form of tablets for treating intestinal disorders Nanocellulose films for screening of biological compounds and nucleic acids encoding a biological compound Filter medium partly based on nanocellulose for leukocyte free blood transfusion A buccodental formulation, comprising nanocellulose and a polyhydroxylated organic compound Powdered nanocellulose has also been suggested as an excipient in pharmaceutical compositions Nanocellulose in compositions of a photoreactive noxious substance purging agent Elastic cryo-structured gels for potential biomedical and biotechnological application Matrix for 3D cell culture
Silicosis is the most common occupational lung disease worldwide. Because of work-exposure to silica dust, silicosis is an occupational hazard to construction, railroad, demolition, mining, sandblasting, quarry, tunnelling, ceramics and foundry workers, as well as grinders, stone countertop fabricators, refractory brick workers, tombstone workers, workers in the oil and gas industry, pottery workers, fiberglass manufacturing, glass manufacturing, flintknappers and others. Brief or casual exposure to low levels of crystalline silica dust do not produce clinically significant lung disease. In the United States, it is estimated that between one and two million workers have had occupational exposure to crystalline silica dust and 59,000 of these workers will develop silicosis sometime in the course of their lives. In the US between 1995 and 2004, there was an annual recorded average of roughly 30 silicosis-related deaths. In the UK, the latest data from The Health and Safety Executive show that there are typically between 10 and 20 annual silicosis deaths in recent years, with an average of 12 per year over the last 10 years. There has been a recent rise of cases in Australia, China and the United States associated with the manufacture and installation of engineered stone surfaces in kitchens and bathrooms. Engineered stone has become increasingly common, and it contains a very high proportion of silica, more than natural stone.
Sources: en.wikipedia.org
Plutonium-241 (241Pu, Pu-241) is an isotope of plutonium formed when plutonium-240 captures a neutron. Like some other plutonium isotopes (especially 239Pu), 241Pu is fissile, with a neutron absorption cross section about one-third greater than that of 239Pu, and a similar probability of fissioning on neutron absorption, around 73%. In the non-fission case, neutron capture produces plutonium-242. In general, isotopes with an odd number of neutrons are both more likely to absorb a neutron and more likely to undergo fission on neutron absorption than isotopes with an even number of neutrons.
The elections, while a landmark of democratic transformation, were also shaped significantly by external influences particularly from West Germany. Writer Michael Schneider was among those who criticised what he viewed as overwhelming interference by West German politicians and institutions. In his work, he described the campaign environment as one saturated with West German personalities, party activists and messaging. West German political parties, especially its branches of the Christian Democratic Union (CDU) and Social Democratic Party (SPD), sent campaigners and resources across the border to bolster their East German affiliates. According to Schneider, taxpayer funds from West Germany were used to support this mobilisation, raising questions about the balance of influence and the fairness of the electoral playing field. Civil rights activist and co-founder of the New Forum, Jens Reich, echoed these concerns from the perspective of the East German opposition. Speaking two decades after the vote, he reflected that the entire West German political apparatus had been transplanted into the East, overwhelming grassroots democratic movements that had played a key role in the Peaceful Revolution. In his words, "The Bonn hippopotamus came in such a mass that you were simply helpless." Reich observed that the election campaign bore little resemblance to a homegrown democratic process and instead felt like a western-style election exported wholesale into a fragile new democracy.
== Ergothioneine derivatives == Various derivatives of ergothioneine have been reported in the literature, such as S-methyl-ergothioneine or selenium-containing selenoneine. The latter is made using the same biosynthetic pathway as ergothioneine when selenocysteine is present.
Sources: en.wikipedia.org
=== Coupling CE with MALDI-MS === Off-line coupling of CE to MALDI, the CE effluent could be sprayed or added drop wise on MALDI target plate then dried and analyzed by MS. For online coupling, a moving target with continuous contact to CE capillary end is required. The moving target takes analytes into MS where it is desorbed and ionized. Musyimi et al. developed a new technique where rotating ball was used to transfer CE to MS. The sample from CE is mixed with matrix coming though another capillary. As the ball rotates the sample is dried before it reaches ionization region. This technique has high sensitivity since no makeup fluid is used.
=== Chemical disinfection with halogens === Chemical disinfection with halogens, chiefly chlorine and iodine, results from oxidation of essential cellular structures and enzymes. The primary factors that determine the rate and proportion of microorganisms killed are the residual or available halogen concentration and the exposure time. Secondary factors are pathogen species, water temperature, pH, and organic contaminants. In field-water disinfection, use of concentrations of 1–16 mg/L for 10–60 min is generally effective. Of note, Cryptosporidium oocysts, likely Cyclospora species, Ascaris eggs are extremely resistant to halogens and field inactivation may not be practical with bleach and iodine.
=== Diving === Barotrauma may be caused when diving, either from being crushed, or squeezed, on descent or by stretching and bursting on ascent; both can be avoided by equalising the pressures. A negative, unbalanced pressure is known as a squeeze, crushing eardrums, dry suit, lungs or mask inwards and can be equalised by putting air into the squeezed space. A positive unbalanced pressure expands internal spaces rupturing tissue and can be equalised by letting air out, for example by exhaling. Both may cause barotrauma. There are a variety of techniques depending on the affected area and whether the pressure inequality is a squeeze or an expansion:
Sources: en.wikipedia.org
Epitalon is a synthetic tetrapeptide composed of four amino acids: alanine, glutamate, aspartate, and glycine. It is written as Ala-Glu-Asp-Gly. The free peptide has a molecular weight of about 390 daltons and is normally supplied as a lyophilized powder.
No. Epitalon is chemically synthesized, not extracted. It was designed as a short synthetic fragment conceptually related to larger pineal peptides studied in the same research tradition, particularly the extract known as epithalamin. The two are distinct materials with different compositions.
The term bioregulator is used in this research tradition for short peptides proposed to influence gene expression or cell function. Epitalon is grouped with other synthetic short peptides under this label. The term reflects a proposed mechanism rather than an established drug classification.
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.