The short version of tetrapeptide fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2025-10-17. Anything still debated is marked as such rather than presented as settled.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C14H22N4O9 | Free acid form of the tetrapeptide |
| Molecular mass | About 390.35 Da | Calculated monoisotopic value |
| Appearance | White to off-white powder | Typical lyophilized presentation |
| Solubility | Soluble in water | Also dissolves in buffered saline |
| Storage temperature | Minus 20 degrees Celsius | Dry, dark conditions; avoid repeated thawing |
Epitalon is a synthetic four-amino-acid peptide with the sequence alanine-glutamate-aspartate-glycine, commonly abbreviated AEDG. Its molecular formula is C14H22N4O9, and its calculated molar mass is approximately 390.35 grams per mole. The compound is a short fragment related to a peptide fraction isolated from bovine pineal gland extracts, and it is normally supplied as a lyophilised powder intended for laboratory research. It is not a registered pharmaceutical product in most countries.
The peptide emerged from research carried out in Saint Petersburg from the late 1980s onward, where investigators searched for shorter active fragments of a pineal preparation known as epithalamin. The name epitalon was chosen to reflect that parent extract. Early reports described effects on neuroendocrine markers and on the lifespan of laboratory animals. Much of that work appeared in Russian-language journals, with English translations following later, which affects how readily the original protocols can be assessed by outside groups.
（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.
Acronyms used: HFC – Human frontal cortex receptor MB – Mouse brain receptor RC – Cloned rat receptor A study measuring the in vivo receptor occupancies of 13 schizophrenic patients treated with 5.7 ± 1.4 mg/day of flupentixol found 50-70% receptor occupancy for D2, 20 ± 5% for D1, and 20 ± 10% for 5-HT2A. Its antipsychotic effects are predominantly a function of D2 antagonism. Its antidepressant effects at lower doses are not well understood; however, it may be mediated by functional selectivity and/or preferentially binding to D2 autoreceptors at low doses, resulting in increased postsynaptic activation via higher dopamine levels. Flupentixol's demonstrated ability to raise dopamine levels in mice and flies lends credibility to the supposition of autoreceptor bias. Functional selectivity may be responsible through causing preferential autoreceptor binding or other means. The effective dosage guideline for an antipsychotic is very closely related to its receptor residency time (i.e., where drugs like aripiprazole take several minutes or more to disassociate from a receptor while drugs like quetiapine and clozapine—with guideline dosages in the hundreds of milligrams—take under 30s) and long receptor residency time is strongly correlated with likehood of pronounced functional selectivity; thus, with a maximum guideline dose of only 18 mg/day for schizophrenia, there is a significant possibility of this drug possessing unique signalling characteristics that permit counterintuitive dopaminergic action at low doses. Flupentixol also inhibits tubulin polymerization.
==== Total ==== The total duration of a substance can be defined as the amount of time it takes for the effects of a substance to completely wear off into sobriety, starting from the moment the substance is first administered.
Consuming 75% of production, the primary use for strontium was in glass for colour television cathode-ray tubes, where it prevented X-ray emission. This application for strontium has been declining because CRTs are being replaced by other display methods. This decline has a significant influence on the mining and refining of strontium. All parts of the CRT must absorb X-rays. In the neck and the funnel of the tube, lead glass is used for this purpose, but this type of glass shows a browning effect due to the interaction of the X-rays with the glass. Therefore, the front panel is made from a different glass mixture with strontium and barium to absorb the X-rays. The average values for the glass mixture determined for a recycling study in 2005 is 8.5% strontium oxide and 10% barium oxide. Because strontium is so similar to calcium, it is incorporated in the bone. All four stable isotopes are incorporated, in roughly the same proportions they are found in nature. However, the actual distribution of the isotopes tends to vary greatly from one geographical location to another. Thus, analyzing the bone of an individual can help determine the region it came from. This approach helps to identify the ancient migration patterns and the origin of commingled human remains in battlefield burial sites. 87Sr/86Sr ratios are commonly used to determine the likely provenance areas of sediment in natural systems, especially in marine and fluvial environments.
Sources: en.wikipedia.org
Akram Elias is a businessman from Lebanon living in Washington, D.C., who was the founder and CEO of a private consulting firm in the city called Capital Communications Group. Elias was initiated as a Freemason in 1996, and by 2008 was the Most Worshipful Brother (former Master) of Potomac Lodge No. 5, but had also been raised into stature within the Grand Lodge of Masonic Education and the Grand Lodge of Washington, D. C. The first time he toured Cuba was in 2001, and he made several trips over the years. On one of those trips, in 2004, he personally met Grand Master Collera Venta to discuss Freemasonry in America (e.g., the Americas), and the future of Cuban Freemasonry. In 2004, Alan Gross, a Maryland man from DAI Global, a subcontracting company for USAID, carried a package of electronics equipment and money to Cuba for Marc Wachtenheim. Gross didn't know any Spanish, and was not an expert on Cuba. Gross delivered this package to Grand Master Collera Venta. Gross made five trips to the island between 2004 and 2009, smuggling communications equipment to Collera Venta every time. Certain items that Alan Gross carried into Cuba were BGAN satellite internet links into Jewish communities to circumvent the Cuban firewall. Gross also reached out to Jewish American humanitarian organizations like the Jewish Federations of North America and their chapter in Broward County, Florida, to smuggle contraband items into Jewish communities in Cuba to allow them to communicate to the outside world.
Pornanong Aramwit (Thai: พรอนงค์ อร่ามวิทย์, RTGS: Phon-anong Aramwit; born 1970) is a pharmaceutical scientist, pharmacist, academic, and author. She serves as the Vice President in Research and Innovation at Chulalongkorn University (CU) and is also a member of the university's Council, Administrative Board of the National Innovation Agency, and the Royal Society of Thailand. Aramwit's research has encompassed protein research, including silk proteins, biomaterials, tissue engineering, and herbal substances. She has conducted clinical studies in nephrology and dermatology, focusing on materials for wound healing applications. She is an inventor of medical devices and in the food industry, and has received awards including the Merits of Leadership Award Grand Officer Level: Number of the cross 1156 from the UK, the Merits of Innovation Grand Officer Level: Number of the cross 30705 from France, and the Merits of Innovation Ribbon of Honor: Number of the cross 16834 from Belgium, as well as from the European Union and Spain. Additionally, she was awarded the 2018 Ambassador Award for Innovator with Outstanding Achievements, the 2019 Outstanding Professional Women Award by the Federation of Business and Professional Women of Thailand, and the 2024 National Outstanding Researcher Award by the National Research Council of Thailand (NRCT). Aramwit has authored more than 220 peer-reviewed articles, authored/co-authored several books and book chapters, and has 20 patents.
=== Safety === When 3D printing food, safety is very crucial. A food printer must ensure safety along the entire path taken by the food material. Due to the possibility of food getting stuck somewhere along the path, bacteria accumulation is a major concern. Microbial stability is a crucial parameter of the quality of the printed food, thus it needs to be addressed both during the design of the printer and during the printing process. On the other hand, the materials that come into contact with the food may not be as significant of a concern since high quality printers use stainless steel and BPA-free materials.
Sources: en.wikipedia.org
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.
No naturally occurring free form of the peptide has been described. The four-amino-acid sequence can appear as a fragment within larger proteins, but that is not the same as the intact compound being present as a circulating molecule. Materials used in research are synthetic.
Purity is usually checked by reverse-phase high-performance liquid chromatography, which separates the target peptide from related impurities. Mass spectrometry is commonly used alongside it to confirm molecular mass. Some suppliers also provide amino acid analysis for additional sequence confirmation.
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.