Everything below concerns Nucleotide. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2026-03-21. Numbers and descriptions here follow the published literature rather than marketing material.
Two enzymatic steps define the canonical route from nicotinamide to NAD+. Nicotinamide phosphoribosyltransferase, known as NAMPT, produces NMN from nicotinamide and phosphoribosyl pyrophosphate. NMN adenylyltransferases, or NMNAT enzymes, then couple NMN with ATP to form NAD+. Whether intact NMN crosses cell membranes efficiently remains an active area of investigation; some studies propose direct transport, while others emphasize extracellular dephosphorylation to nicotinamide riboside followed by uptake. The relative contribution of each route likely depends on cell type, tissue, and experimental conditions.
Trace amounts of NMN have been reported in certain plant foods, including edamame, avocado, broccoli, cucumber, and cabbage. Reported concentrations vary widely because analytical methods differ and food matrices complicate extraction. Endogenous production in cells is generally considered more quantitatively important than dietary intake, though precise human turnover rates are difficult to establish. Commercial NMN for research or consumer products is commonly made through enzymatic synthesis or chemical phosphorylation routes. Regulatory classification differs by country; in some jurisdictions NMN is sold as a supplement, while in others it is treated as a novel food ingredient or restricted substance.
Nicotinamide mononucleotide, abbreviated NMN, is a naturally occurring nucleotide found in cells. Its structure combines a nicotinamide ring, a ribose sugar, and a phosphate group. As an intermediate in the NAD+ salvage pathway, NMN is converted to nicotinamide adenine dinucleotide, a coenzyme central to cellular redox reactions. NAD+ also serves as a substrate for enzymes involved in DNA repair, stress responses, and metabolic regulation. The compound is therefore part of normal cellular biochemistry rather than an exclusively synthetic molecule.
Nicotinamide mononucleotide, abbreviated NMN, is a naturally occurring nucleotide found in the cells of many organisms, including bacteria, plants, and mammals. Its structure consists of a nicotinamide ring attached to a ribose-phosphate group. NMN functions as an intermediate in the NAD+ salvage pathway, a recycling route that regenerates nicotinamide adenine dinucleotide. The enzyme nicotinamide phosphoribosyltransferase produces NMN from nicotinamide and phosphoribosyl pyrophosphate. A second enzyme, NMN adenylyltransferase, then converts NMN into NAD+.
Dietary sources of NMN include small amounts in certain vegetables, fruits, and other foods, although exact values vary by sample and method. Endogenous NMN concentrations are tightly regulated and often low, making measurement in blood or tissues technically demanding. After oral intake, NMN is thought to be rapidly metabolized in the intestine and liver, and intact NMN may not reach all tissues at high levels. Some rodent studies report increases in tissue NAD+ after oral NMN, while human data remain limited and sometimes rely on blood NAD+ metabolites rather than direct tissue measures.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C11H15N2O8P | Canonical beta anomer; charge state depends on pH. |
| Molar mass | 334.22 g/mol | Calculated for the neutral formula. |
| CAS Registry Number | 1094-61-7 | Common identifier for beta-nicotinamide mononucleotide. |
| Appearance | White to off-white powder or crystals | Varies with purity, hydration, and polymorphism. |
| Solubility | Freely soluble in water; low solubility in nonpolar solvents | Reported values depend on salt form and temperature. |
Nicotinamide mononucleotide, commonly abbreviated NMN, is a pyridine nucleotide that consists of a nicotinamide ring, a ribose sugar, and a phosphate group. It is an intermediate in the salvage pathway for nicotinamide adenine dinucleotide, or NAD+, synthesis. In mammalian cells, the enzyme nicotinamide phosphoribosyltransferase produces NMN from nicotinamide and phosphoribosyl pyrophosphate. Nicotinamide mononucleotide adenylyltransferases then convert NMN into NAD+. The core structure and enzymatic route are well established in biochemical literature.
The biologically relevant form of NMN is generally the beta anomer, which is recognized by NMN adenylyltransferases. NMN is polar and water soluble, and it does not readily diffuse across lipid membranes without assistance. Whether intact NMN enters cells through a specific transporter remains an open question; some studies propose solute carrier family members, while other work favors extracellular dephosphorylation to nicotinamide riboside followed by uptake. This transport and compartmentalization debate affects how researchers interpret oral administration studies. The distinction between intracellular synthesis and extracellular delivery is central to current discussion.
Terminology around NMN can be confusing because several related compounds share the vitamin B3 family. Nicotinamide riboside is a nucleoside, whereas NMN is a nucleotide with a phosphate group, and NAD+ is a dinucleotide coenzyme rather than a simple precursor. Niacin and nicotinamide are also NAD+ precursors but follow different metabolic entry points. In commercial and scientific writing, NMN usually refers to beta-nicotinamide mononucleotide unless another form is specified. Consistent nomenclature helps distinguish chemical identity from proposed biological effects.
In the salvage pathway, NMN is generated from nicotinamide and 5-phosphoribosyl-1-pyrophosphate by the enzyme nicotinamide phosphoribosyltransferase. A second route produces NMN from nicotinamide riboside through phosphorylation by nicotinamide riboside kinases. NMN is then converted to NAD+ by nicotinamide mononucleotide adenylyltransferases, often called NMNAT enzymes. This stepwise route allows cells to recycle nicotinamide and maintain NAD+ levels under changing metabolic conditions. The relative contribution of each route varies by tissue, species, and physiological state, and it remains an active area of research.
Research on NMN has expanded because NAD+ concentrations decline with age in some tissues and because NAD+ participates in energy metabolism, DNA repair, and signaling. Animal studies have reported changes in NAD+ levels after NMN administration, but human data are more limited and often focus on safety, pharmacokinetics, and biomarker changes. Questions remain about oral absorption, tissue distribution, and whether changes in blood NAD+ reflect changes inside specific organs. NMN is not an approved drug, and claims about its clinical effects should be distinguished from established biochemical findings.
NMN is present in small amounts in various foods, including certain vegetables, fruits, and milk, though dietary quantities are generally low. Laboratory research often uses synthetic or enzymatically produced NMN. The compound has drawn interest because NAD+ levels decline with age in some tissues and because restoring NAD+ may affect metabolism in animal models. Whether oral NMN produces meaningful NAD+ increases in humans and whether such changes translate into health benefits are not fully established.
Nicotinamide mononucleotide, abbreviated NMN, is a naturally occurring nucleotide. Its structure combines a nicotinamide base with a ribose sugar and a phosphate group. Within cells, NMN sits on the biosynthetic route that recycles nicotinamide back into nicotinamide adenine dinucleotide, or NAD+. Because NAD+ participates in redox reactions and signaling, enzymes that produce and consume it influence many metabolic processes. The compound is therefore best described as an intermediate rather than a final signaling molecule.
In the canonical salvage pathway, nicotinamide phosphoribosyltransferase, known as NAMPT, transfers a phosphoribosyl group to nicotinamide and releases NMN. A second enzyme, NMN adenylyltransferase, then attaches an adenylyl group to NMN to form NAD+. Alternative routes exist, including a pathway that uses nicotinamide riboside and its phosphorylated forms. The relative contribution of extracellular NMN to intracellular NAD+ pools remains an area of active investigation, and the roles of specific transporters and enzymes are not completely defined.
Beyond its intracellular synthesis, NMN can be taken up from the extracellular environment, although the routes are still debated. Some evidence points to direct transport into cells through specific transporters, while other work suggests dephosphorylation to nicotinamide riboside followed by cellular uptake. Once inside, NMN can be converted to NAD+ by NMN adenylyltransferases; the relative contribution of these routes may differ by tissue, species, and experimental conditions. Researchers continue to investigate which mechanisms dominate in intact organisms and how they affect measured NAD+ levels. Direct measurement in tissues remains technically challenging because NMN can be rapidly metabolized during sample collection.
NMN occurs in many living systems, including bacteria, yeast, plants, and mammals. Dietary sources are present in foods such as edamame, avocado, broccoli, and various meats, but amounts vary widely and are generally lower than those used in research settings. Laboratory production often relies on enzymatic synthesis or chemical phosphorylation of nicotinamide riboside, and commercial material is typically supplied as a white to off-white powder. Because NMN is hygroscopic and sensitive to heat, moisture, and pH extremes, its handling requires care to preserve identity and purity. Aqueous preparation should be done with attention to pH and temperature to limit hydrolysis.
=== Identification of Protopodocarpoxylon === Protopodocarpoxylon is an extinct genus of conifer tracheophytes, now often found as fossilized woods. In a 2007 study, extraction and identification of biomarkers from fossil woods collected in south-central Poland allowed for the identification of the sample as Protopodocarpoxylon Eckhold. Samples of the wood were collected from clays and carbonate concretions then cleaned of contaminants before being pulverized, and the organics extracted. The extracts were derivatized with TMS and then subjected to gas chromatography-mass spectrometry (GC-MS) analysis. Multiple abietanes were detected in the analyzed samples, with ferruginol, sugiol, simonellite, and dehydroabietane present in all four of the samples tested. Sugiol and ferruginol were both detected as unaltered natural products. There was a dramatic difference in detected abundance of sugiol and ferruginol in samples that were more oxidized, but the biomarkers were still detectable in both cases. The unknown fossil wood samples were determined to contain aliphatic lipids (n-alkanols and n-alkanoic acids), diterpenoids (abietanes, labdanes, and totaranes), triterpenoids (lupane and hopane), and steroids. The presence of long chain n-alkanes, ferruginol, sugiol, and dehydroabietic acid were considered and the sample was determined to be a conifer plant, in either the Podocarpaceae, Cupressaceae, or Araucariaceae family.
Because of this, and also because the high-glycerol method seems to protect the red blood cells better and is associated with less haemolysis than the low-glycerol method, the high-glycerol method is often preferred.
== History == Benorterone was developed in the late 1950s, was first reported to possess antiandrogenic activity in 1964, and was investigated in clinical trials in the mid-to-late 1960s. It was the first known antiandrogen to be studied in humans. The drug was found to be effective in the treatment of acne, seborrhea, and hirsutism in women. In addition, unlike progestogenic antiandrogens such as cyproterone acetate, it seldom produced side effects in women and did not affect menstruation. However, in males, benorterone was not effective for acne, and produced high rates of gynecomastia (in 12 out of 13 or 92% of young men treated with 75 to 300 mg/day benorterone). Shortly following the observance of this side effect, it was withdrawn from clinical studies. Subsequently, cyproterone acetate, which has a greatly reduced risk of gynecomastia by virtue of its concomitant progestogenic and antigonadotropic actions (which results in suppression of estrogen levels), was developed instead and was introduced for medical use in 1973. In addition, spironolactone, a steroidal antimineralocorticoid that was introduced for medical use in 1959, was discovered to possess potent antiandrogenic activity in 1969, and became widely used clinically as an antiandrogen after its first use in an androgen-dependent condition in 1978.
Sources: en.wikipedia.org
== Life == Ogston was educated at Eton College and Balliol College, Oxford. Apart from a period as Freedom Research Fellow at the London Hospital, he spent most of his career at Oxford, being appointed Demonstrator (1938) and Reader (1955) in Biochemistry, and Fellow and Tutor in Physical Chemistry at Balliol (1937). In that capacity he had a major influence on other distinguished scientists, such as the Nobel prizewinner Oliver Smithies, who wrote his first paper with him, and Richard Dawkins, who chose to study zoology on his recommendation. In 1959 he took up an appointment as Professor of Physical Biochemistry at the John Curtin School of Medical Research at the Australian National University (ANU), Canberra, where he remained until 1970, when he returned to Oxford as President of Trinity College. On his retirement in 1978, he held visiting fellowships at the Institute for Cancer Research, Philadelphia and the John Curtin School of Medical Research, ANU. Ogston was elected FRS in 1955, and was awarded Lemberg Medal in 1970 and the Davy Medal in 1986.
== Principles and ethical foundations == Across its applications, harm reduction prioritizes reducing adverse consequences without requiring elimination of the underlying behavior. In drug policy, this orientation is commonly described as pragmatic: it begins from the continued existence of drug use and regards reductions in harm as worthwhile outcomes even when abstinence is not achieved. Ethical defenses have also drawn on consequentialist and rights-based reasoning. Consequentialist arguments emphasize reductions in illness, death, and social costs, while rights-based arguments appeal to autonomy and opposition to paternalism. The harm can be distinguished in physical harms, dependence and social harms including health care costs and community outcomes. Social justice approaches broaden the analysis of harm beyond individual behavior to include poverty, homelessness, criminalization, violence, stigma, and barriers to health care. From this perspective, harm reduction may respond to structural inequities as well as immediate individual risk. Relational and participatory approaches emphasize that people who use drugs possess knowledge relevant to effective services and should participate in their design and governance. User-led organizations and peer practices have been important within this tradition. Ethical analysis of harm-reduction research has also used communitarian approaches, emphasizing social relationships and responsibilities alongside individual rights.
Like many other sea anemones, S. helianthus excretes a variety of toxins that can serve different purposes such as prey capture, protection and defense against predators. In specific, Sticholysin II (St II) is a cytolysin that has been extracted from the nematocysts of Sun Anemones and further examined by method of immunoperoxidase staining (structure included- Pennington et al.). Basulto et al. concludes that Sticholysin II functions in exclusive roles within the anemone's physiology, including predation and digestion. Another study revealed a similar lysin, known as Sticholysin I (St I), suggesting multiple isoforms of the same lysin. These two Sticholysins are further expanded on by Alvarez et al., whereas they are described as “pore-forming toxins”. S. helianthus are also capable of producing polypeptide neurotoxins. Kem et al. reports a study where a newly found variant of actiniid neurotoxin, namely Sh 1, was extracted from S. helianthus and yielded genetic similarity to toxin II of Heteractic paumotensis., another species in family Stichodactylidae.
Sources: en.wikipedia.org
NMN is nicotinamide mononucleotide, a nucleotide intermediate in NAD+ metabolism. It occurs naturally in cells and can also be produced synthetically for research or commercial use. Its name reflects its composition: nicotinamide, ribose, and a phosphate group.
NMN is a direct precursor in the NAD+ salvage pathway. NMNAT enzymes convert NMN and ATP into NAD+, a coenzyme used in many cellular reactions. This relationship makes NMN a focus of studies on NAD+ metabolism.
Small amounts of NMN have been reported in some plant foods, but measured levels vary and are not consistently quantified. Dietary contribution is generally considered minor compared with endogenous production. Food-matrix effects make accurate analysis difficult.
NMN is nicotinamide mononucleotide, a nucleotide intermediate in the NAD+ salvage pathway. Cells use it to help regenerate NAD+, a coenzyme involved in energy metabolism and cellular signaling. It is present naturally in many organisms and is also produced synthetically for research and consumer products.