A practical reference on AEDG: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-05-08 and is reviewed periodically as new material appears.
Solubility is high in water, phosphate-buffered saline and normal saline, a pattern that follows from the two acidic residues in the chain. The peptide dissolves poorly in non-polar solvents such as hexane or chloroform. Stock solutions are often prepared in water first and then diluted into the buffer of interest. Because the molecule is small and hydrophilic, filtration through a low-protein-binding membrane is usually straightforward, and visible particulates are uncommon in freshly made solutions.
Identity and purity are established with reversed-phase high-performance liquid chromatography and mass spectrometry. The chromatogram shows the main peak and any truncated or oxidised by-products, while the mass spectrum confirms the expected 390 dalton mass. Amino acid analysis can corroborate composition when a sample's origin is uncertain. Counterion content, particularly residual trifluoroacetate from purification, is frequently reported alongside purity because it shifts the net mass of the solid.
The parent extract epithalamin was characterised as a low-molecular-weight fraction of pineal tissue rather than a single defined chemical entity. Researchers fractionated it and tested successive fragments for activity, a screening approach typical of peptide discovery work in that era. Epitalon emerged from that process as one of the shorter sequences of interest. Because the original extract was never fully resolved into individual components, claims about which constituent drives a given effect rest on inference. This distinction matters when reading older reports that attribute extract observations to the tetrapeptide itself.
Epitalon is a synthetic tetrapeptide with the residue sequence alanine-glutamate-aspartate-glycine, commonly abbreviated AEDG. Its monoisotopic mass is approximately 390.35 daltons, and it is usually supplied as a lyophilised trifluoroacetate or acetate salt. The compound was derived from a pineal gland extract called epithalamin, a heterogeneous preparation investigated in the former Soviet Union. Researchers associated with the Saint Petersburg Institute of Bioregulation and Gerontology described the tetrapeptide as a constituent fragment of that extract. Commercial material is offered as a laboratory reagent rather than as a finished pharmaceutical product.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white powder | Lyophilised and often hygroscopic |
| Solubility class | Freely soluble in water | Poor solubility in non-polar solvents |
| Typical storage temperature | -20 degrees Celsius or colder | Sealed, desiccated, protected from light |
| Typical analytical method | Reversed-phase HPLC with mass spectrometry | Establishes purity and confirms mass |
| Common salt form | Trifluoroacetate or acetate | Counterion reported alongside purity values |
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.
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.
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.
Interest in epitalon is usually discussed within the broader field of short peptide bioregulators, a category that includes other synthetic di-, tri-, and tetrapeptides studied by the same research group. These compounds share a common rationale: that small fragments of tissue-derived proteins can retain biological activity and can be produced reproducibly. The category as a whole remains outside mainstream pharmacological consensus, and epitalon specifically has a limited presence in independent, non-Russian research literature, which shapes how its evidence base is described.
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.
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.
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.
=== Locomotion === The female worker ants do not have wings and reproductive females lose their wings after their mating flights in order to begin their colonies. Therefore, unlike their wasp ancestors, most ants travel by walking. Some species are capable of leaping. For example, Jerdon's jumping ant (Harpegnathos saltator) is able to jump by synchronising the action of its mid and hind pairs of legs. There are several species of gliding ant including Cephalotes atratus; this may be a common trait among arboreal ants with small colonies. Ants with this ability are able to control their horizontal movement so as to catch tree trunks when they fall from atop the forest canopy.
other NSAIDs, corticosteroids: increased frequency of side effects, especially peptic ulcers and gastrointestinal bleeding diuretics, ACE inhibitors and other antihypertensive drugs: reduced effectiveness of these drugs with ACE inhibitors or ciclosporin, increased risk of kidney function disorders anticoagulants such as warfarin: increased risk of bleeding increased blood plasma concentrations of digoxin and methotrexate decreased plasma concentrations of lithium
This formed the basis of Australian fair work regulation, even though R v Barger in 1908 quickly struck down the Excise Tariff Act 1906, saying the federal tax power could not be used to indirectly regulate working conditions. In 1956, R v Kirby held that the CCCA was an unconstitutional court because it held both judicial and powers to arbitrate disputes. So, to replace the CCCA, a new Commonwealth Conciliation and Arbitration Commission carried out mediation functions, and the Commonwealth Industrial Court assumed its powers and itself merged into the Federal Court of Australia in 1977.
Sources: en.wikipedia.org
In February 1917, revolution broke out in Russia in which workers, soldiers and peasants established soviets, the monarchy was forced into exile fell and a provisional government was formed until the election of a constituent assembly. Alexander Kerensky, a Russian lawyer and revolutionary, became a key political figure in the Russian Revolution of 1917. After the February Revolution, Kerensky joined the newly formed Russian Provisional Government, first as Minister of Justice, then as Minister of War and after July as the government's second Minister-Chairman. A leader of the moderate socialist Trudovik faction of the Socialist Revolutionary Party known as the Labour Group, Kerensky was also the vice-chairman of the powerful Petrograd Soviet. After failing to sign a peace treaty with the German Empire to exit from World War I which led to massive popular unrest against the government cabinet, Kerensky's government was overthrown on 7 November by the Bolsheviks led by Vladimir Lenin in the October Revolution. Soon after the October Revolution, the Russian Constituent Assembly elected Socialist-Revolutionary leader Victor Chernov as President of a Russian Republic, but it rejected the Bolshevik proposal that endorsed the Soviet decrees on land, peace and workers' control and acknowledged the power of the Soviets of Workers', Soldiers' and Peasants' Deputies.
Maggot therapy has been shown to accelerate debridement of necrotic wounds and reduce the bacterial load of the wound, leading to earlier healing, reduced wound odor and less pain. The combination and interactions of these actions make maggots an extremely potent tool in chronic wound care. Negative pressure wound therapy (NPWT) is a treatment that improves ischemic tissues and removes wound fluid used by bacteria. This therapy, also known as vacuum-assisted closure, reduces swelling in tissues, which brings more blood and nutrients to the area, as does the negative pressure itself. The treatment also decompresses tissues and alters the shape of cells, causes them to express different mRNAs and to proliferate and produce ECM molecules. Recent technological advancements produced novel approaches such as self-adaptive wound dressings that rely on properties of smart polymers sensitive to changes in humidity levels. The dressing delivers absorption or hydration as needed over each independent wound area and aids in the natural process of autolytic debridement. It effectively removes liquefied slough and necrotic tissue, disintegrated bacterial biofilm as well as harmful exudate components, known to slow the healing process. The treatment also reduces bacterial load by effective evacuation and immobilization of microorganisms from the wound bed, and subsequent chemical binding of available water that is necessary for their replication.
== History == Acetalated dextran was first reported in 2008 out of the lab of Jean Fréchet at the University of California, Berkeley in the College of Chemistry by inventors Eric Bachelder, Tristan Beaudette and Kyle Broaders. This version of acetalated dextran, often abbreviated Ac-DEX, has dextran and exceedingly low levels of acetone and methanol as degradation products. In 2012, in the laboratory of Kristy Ainslie, at Ohio State University in the College of Pharmacy, polymer synthesis was modified to release ethanol in place of methanol upon degradation. The ethanol producing version of acetalated dextran is often abbreviated Ace-DEX.
=== Determining quality === Once tempeh is produced, it is divided into three categories based on its quality: good, unfinished, and inedible. Good tempeh includes beans that are bound into a firm, compact cake by a dense, uniform, white mycelium, which should permeate the entire cake; the beans should be barely visible. The odor of good tempeh should be pleasant, clean, subtly sweet or resemble the aroma of mushrooms. The entire tempeh should lift as a single, cohesive cake without crumbling when shaken gently. Unfinished tempeh has beans that are bound together loosely by a sparse white mycelium, hence it crumbles easily. Unfinished tempeh should be incubated longer unless it has been incubated more than eight hours past the recommended time. If it has been incubated for enough time and still remains unfinished, it should be discarded. Inedible tempeh has beans with foul odor, resembling strong ammonia or alcohol, indicating the development of undesirable bacteria due to excess moisture or overheating. Inedible tempeh cake is wet, slimy, and mushy with a collapsed structure. Its color is tan to brown and mold develops in sparse patches.
Sources: en.wikipedia.org
Sauropsida/ Reptilia sensu lato †Araeoscelidia? †Parareptilia (polyphyletic) Diapsida/Neodiapsida †Drepanosauromorpha (placement uncertain) †Younginiformes (likely paraphyletic) †Ichthyosauromorpha (placement uncertain) †Thalattosauria (placement uncertain) †Sauropterygia (placement uncertain) †Choristodera (placement uncertain) †Kuehneosauridae (placement uncertain) Sauria/ Reptilia sensu stricto Lepidosauromorpha Lepidosauria Rhynchocephalia (tuatara) Squamata (lizards and snakes) Pantestudines (turtles and kin, placement uncertain) Archosauromorpha †Protorosauria (paraphyletic) †Rhynchosauria †Allokotosauria Archosauriformes †Phytosauria Archosauria Pseudosuchia Crocodilia (crocodilians) Avemetatarsalia/Ornithodira †Pterosauria Dinosauria †Ornithischia Saurischia (including birds (Aves))
== Awards and honours == 1923: Nobel Prize in Physiology or Medicine for the discovery of insulin – shared with John Macleod 1923: John Scott Medal of the Franklin Institute 1927: Cameron Prize for Therapeutics of the University of Edinburgh 1931: Flavelle Medal of the Royal Society of Canada 1935: Fellowship of the Royal Society Prior to the award of the Nobel Prize in Physiology or Medicine for 1923—which he shared with Macleod—he received the Reeve Prize of the University of Toronto (1922). In 1923, the Canadian Parliament granted him a Life Annuity of $7,500. Following the Banting's receipt of the Cameron Prize for Therapeutics of the University of Edinburgh in 1927, Banting gave the 1928 Cameron Lecture in Edinburgh. He was a member of numerous medical academies and societies in Canada and abroad, including the British and American Physiological Societies, and the American Pharmacological Society. In 1934, he was knighted as a Knight Commander of the Order of the British Empire (KBE) by King George V and became an active vice-president of the Diabetic Association (now Diabetes UK). In May 1935 he was elected a Fellow of the Royal Society. In 2004, Banting was inducted into the National Inventors Hall of Fame.
The absence of the enzyme has no negative effect on growth and the bacteria show no phenotypeic differences, with the exception that lactobacillic acid or other cyclopropanoic acids do not occur among the fatty acids present. A similar experiment was carried out with artificially produced mutants of Brucella abortus. The bacteria are still able to multiply in macrophages, so lactobacillic acid has no effect on the intracellular life cycle. However, if the bacteria are cultivated in a culture medium with a low pH value and high osmolarity, less growth can be observed compared to the unmodified cells. These conditions can be transferred to the survival of B. abortus in the environment, where an acidic environment with high osmolarity can also occur. The mutants that do not produce lactobacillic acid have poorer chances of survival there and consequently cannot be transferred to a host as easily as is the case with a smear infection, for example. The study of the promoter of the cfa gene also shows that expression is promoted by low pH and high osmolarity, i.e. the enzyme CFA synthase is formed under these conditions. From the point of view of energy metabolism, the formation of the cyclopropane ring in lactobacillic acid means a relatively high energy expenditure for the cell. The S adenosylmethionine, which acts as a carrier of the methylene group, must then be regenerated from S adenosylhomocysteine. This is associated with the hydrolytic cleavage of three ATP molecules per molecule.
Sources: en.wikipedia.org
Sealed lyophilised powder is normally kept at minus twenty degrees Celsius or below, away from light and moisture. Vials are allowed to reach room temperature before opening to limit condensation. Repeated warming and cooling of the same vial is discouraged.
Reversed-phase HPLC establishes purity and separation from related peptides, and mass spectrometry confirms the molecular mass. Amino acid analysis can verify residue composition. No single method proves identity on its own, so the results are read together.
Yes. Residual trifluoroacetate or acetate from purification adds mass and can shift the value obtained by certain assays. Purity figures are therefore meaningful only when the counterion form is stated. Reporting both peptide content and salt form gives a clearer picture.
It is based on epithalamin, a peptide-rich preparation obtained from pineal gland tissue and studied in the former Soviet Union. Researchers later identified the tetrapeptide AEDG as a constituent fragment of that material. Modern supplies are produced by chemical synthesis rather than tissue extraction.