Hygroscopicity comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2026-06-30. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
Regulatory treatment of NMN differs by country and has changed over time. In the United States, the Food and Drug Administration has stated that NMN is excluded from the definition of a dietary supplement because it was investigated as a drug before being marketed as a supplement; enforcement and legal interpretation continue to evolve. In the European Union, NMN may require authorization as a novel food before sale. In Japan, NMN has been marketed in some food products, while it is not approved as a therapeutic drug in major markets. These categories affect labeling, permitted claims, and quality oversight.
Solid NMN is generally handled as a moisture-sensitive and light-sensitive material. Suppliers commonly recommend storage at minus 20 degrees Celsius in a sealed, desiccated container, protected from light. Aqueous solutions are less stable than the solid and may degrade faster at elevated temperatures or extreme pH values. Because NMN contains a phosphate ester and a glycosidic bond, hydrolysis and other degradation pathways are plausible under unfavorable conditions. Stability data from independent laboratories remain limited, so handling recommendations often reflect supplier practice rather than published consensus.
| 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. |
The term NMN commonly refers to the beta isomer, in which the nicotinamide group is attached to the ribose through a beta-glycosidic bond. Commercial material may be supplied as the free acid or as a salt, such as a sodium salt, which affects molecular weight and water solubility. Related compounds include nicotinamide riboside and NAD+ itself, but these are distinct molecules with different formulas and cellular handling. Laboratory research often uses the beta form because it matches the naturally occurring configuration found in biological systems.
Small amounts of NMN occur in some foods, including certain vegetables, fruits, and animal products, though the quantities are generally low and variable. Human cells also synthesize NMN internally from nicotinamide and other precursors. Research interest increased after studies examined whether raising NAD+ levels affects metabolism and aging-related pathways in animals. Evidence in humans remains limited and mixed for many outcomes, and questions about effective absorption, tissue delivery, and long-term effects are still open. Regulatory status differs by country, with some markets treating NMN as a supplement ingredient and others restricting its sale.
Quality control for NMN focuses on identity, purity, residual solvents, heavy metals, and microbial limits. Because the molecule can absorb water, moisture content and packaging are relevant to shelf life. Suppliers may provide certificates of analysis, but independent verification is often needed for research or commercial use. The long-term stability of different crystal forms, salt forms, and formulations is not fully characterized in the public literature. Some degradation products and their effects on product performance remain open questions.
As a commercial ingredient, nicotinamide mononucleotide is commonly supplied as a powder or capsule. Its stability depends on temperature, moisture, pH, and light exposure. Hydrolytic and thermal degradation can increase over time, so manufacturers and laboratories often store material cold and dry. Purity is typically assessed with chromatographic methods, and identity can be confirmed by mass spectrometry. Published stability data for specific finished products remain limited. More data would help define shelf life under real-world conditions.
Natural sources of NMN include mammals, plants, and microorganisms, where it functions as an intermediate in NAD+ salvage and biosynthesis pathways. In mammals, the enzyme nicotinamide phosphoribosyltransferase produces NMN from nicotinamide and phosphoribosyl pyrophosphate. NMN is then converted to NAD+ by nicotinamide mononucleotide adenylyltransferase. Some foods contain measurable NMN, but reported amounts vary widely by species, tissue, and analytical method. The extent to which dietary NMN contributes to cellular NAD+ pools remains an open research question.
Chemically, NMN is described by the molecular formula C11H15N2O8P and a molecular mass near 334.22 g/mol. The beta anomer has a CAS Registry Number of 1094-61-7. It is typically supplied as a white to off-white powder for laboratory use. The molecule carries a phosphate group and a positively charged nicotinamide ring, giving it polar and water-soluble character. These properties influence how it is detected, purified, and stored in research and analytical laboratories.
Solid NMN is a polar, water-soluble nucleotide that can absorb moisture from air. Its phosphate ester is susceptible to hydrolysis, and degradation is faster in aqueous solution, under strongly acidic or alkaline conditions, and at elevated temperatures. For laboratory and commercial handling, the solid is typically kept desiccated, protected from light, and stored frozen. Repeated freeze-thaw cycles can introduce moisture and accelerate breakdown. Stability data for specific formulations should be generated rather than assumed from the parent compound.
Identity and purity of NMN are commonly assessed by liquid chromatography with ultraviolet detection or mass spectrometry. High-performance liquid chromatography can separate related impurities such as nicotinamide, nicotinamide riboside, and NAD+ depending on the method. Mass spectrometry provides molecular mass confirmation, while nuclear magnetic resonance spectroscopy helps establish structure and anomeric form. Quantitative assays often use calibration curves and, in biological samples, stable isotope-labeled internal standards. Method validation addresses specificity, linearity, accuracy, precision, and limits of detection.
=== Haymarket grows === From the autumn of 1964, Haymarket set out aggressively to acquire magazines, approaching them from the list in the media directory BRAD. They acquired small, modestly profitable magazines for tape recorder and camera, and camping and caravan, enthusiasts, and using a loan from BPC bought a series of leisure and medical publications for £250,000 from a Canadian publisher, in competition with Thomson Group. In 1965 Heseltine's businesses had a turnover of around £700,000 per annum, and employed around 50 staff. Although the Opportunities for Graduates series continued to generate profits, Town magazine continued to lose money, hampered by the cost of printing (much more expensive at that time than nowadays) and by Heseltine's reluctance, for political reasons, to include pictures of nude girls or cartoons disrespectful of the Royal Family. Haymarket launched a bid for the British Institute of Management's magazine The Manager, again in competition with Thomson Group, in late 1965. It was envisaged that Haymarket would take a 25% stake, as would the Financial Times and The Economist, of both of which Crowther was also chairman. Over the weekend Heseltine, inspired by how Donald Stokes had once won a Scandinavian bus contract for British Leyland by building a model bus, had a team led by Labovitch prepare a 96-page mock copy of what they envisaged, mostly using text cut from The Economist.
== Work == Born in Melbourne, Australia, Bottomley earned a BSc in physics from Monash University in Australia in 1974. In 1975, he started his PhD in physics at the University of Nottingham in England, in one of the three original groups that began MRI. In Raymond Andrew's group, alongside that of Peter Mansfield, they built the first MRI system producing radiographic-quality images of the human wrist, and he performed the initial work on RF-field and power deposition in human MRI. Upon completing his PhD in 1978, he went to Johns Hopkins University in Baltimore in the USA to adapt MRI methods for spatially localizing MRS signals, initially using surface coils to demonstrate localized metabolite depletion and reversal in regional myocardial ischemia in vivo. In 1980, Paul joined the GE Research Center in Schenectady NY. Together with William A. Edelstein and others, this group began GE's entry into MRI technology. They ordered the biggest magnet available at the time – a 1.5 tesla system – and built the first high-field whole-body MRI/MRS scanner, overcoming problems of coil design, RF penetration and signal-to-noise concerns. The results translated into the highly successful 1.5 tesla clinical MRI products of which there are well over 20,000 systems today, representing 60-70% of all systems. Using a combination of switched MRI localizing magnetic field gradients with MRS acquisition, Paul and his colleagues performed the first noninvasive localized MRS of the human heart and brain.
=== Celiac disease === Since the consumption of gluten is suppressed or reduced with a low-FODMAP diet, the improvement of the digestive symptoms with this diet may not be related to the withdrawal of the FODMAPs, but of gluten, indicating the presence of an unrecognized celiac disease, avoiding its diagnosis and correct treatment, with the consequent risk of several serious health complications, including various types of cancer.
== History == 3M (then the Minnesota Mining and Manufacturing Company) began producing PFOA by electrochemical fluorination in 1947. Starting in 1951, DuPont purchased PFOA from 3M for use in the manufacturing of specific fluoropolymers—commercially branded as Teflon—but DuPont internally referred to PFOA as C8. In 1968, organofluorine content was detected in the blood serum of consumers, and in 1976 it was suggested to be PFOA or a related compound such as PFOS. In 1999, EPA ordered companies to examine the effects of perfluorinated chemicals after receiving data on the global distribution and toxicity of PFOS. For these reasons, and EPA pressure, in May 2000, 3M announced the phaseout of the production of PFOA, PFOS, and PFOS-related products—the company's best-selling repellent. 3M stated that they would have made the same decision regardless of EPA pressure. Because of the 3M phaseout, in 2002, DuPont built its own plant in Fayetteville, North Carolina, to manufacture the chemical. The chemical has received attention due to litigation from the PFOA-contaminated community around DuPont's Washington Works facility in Washington, West Virginia, along with EPA focus. In 2004, ChemRisk—an "industry risk assessor" that had been contracted by Dupont, reported that over 1.7 million pounds of C8 had been "dumped, poured and released" into the environment from Dupont's Parkersburg, West Virginia-based Washington Works plant between 1951 and 2003.
In biology, a sequence motif is a nucleotide or amino-acid sequence pattern that is widespread and usually assumed to be related to biological function of the macromolecule. For example, an N-glycosylation site motif can be defined as Asn, followed by anything but Pro, followed by either Ser or Thr, followed by anything but Pro residue.
Sources: en.wikipedia.org
Portillo and Robert Key handled the detail and presented Heseltine with a list of options. Various options were leaked to the press to test public reaction, and at one point Heseltine appeared to have settled on a tax graded both according to the size of the property and the number of adults living in it. Major was exasperated by the lack of progress and intervened, and – at Major's insistence – Chancellor Norman Lamont increased VAT by 2.5 percentage points to 17.5% in his April 1991 budget so as to provide a £4.5bn subsidy to bring poll tax bills down. Eventually, as expected, the poll tax was abolished and the new Council Tax was graded according to the size of a property, with the only concession to headcount being a single-person discount. In Crick's view, the outcome was much more Sarah Hogg's and Portillo's and Major's doing than Heseltine's. Heseltine was permitted by his colleagues to explore the option of elected city mayors, although it did not meet with Cabinet approval; other ministers were concerned at the likelihood that cities would elect Labour mayors or that there might be deadlock between mayors and local councils. Heseltine also explored the option of unitary authorities (i.e. merging district and county councils), setting up what came to be known as the Banham Commission. Crick regards the commission as a mistake for which Heseltine has received too little blame. The proposals rumbled on for several years, causing annoyance to many Conservative councillors and to their backers in Parliament.
In molecular biology, the flagellar motor switch protein (Flig) is one of three proteins in certain bacteria coded for by the gene fliG. The other two proteins are FliN coded for by fliN, and FliM coded for by fliM. The protein complex regulates the direction of flagellar rotation and hence controls swimming behaviour. The switch is a complex apparatus that responds to signals transduced by the chemotaxis sensory signalling system during chemotactic behaviour. CheY, the chemotaxis response regulator, is believed to act directly on the switch to induce a switch in the flagellar motor direction of rotation.
During the corresponding period some 8,578 actual downloads of the software were independently logged via the same route at the AIDA Website, giving a response rate for this survey of 45%. Responses were received from participants in 66 countries — over half of these (n=2,137; 55.3%) were from the United States and the United Kingdom. There were 2,318 responses (60.0%) received from people with diabetes and 443 (11.5%) from relatives of patients, with fewer responses from doctors, students, diabetes educators, nurses, pharmacists, and other end users. The authors concluded that the study highlighted "considerable interest amongst patients and their relatives to learn more about balancing insulin and diet in diabetes, as well as possibly to get more involved in self-management of insulin dosages. More computer applications that can cater for this interest in diabetes patient self-care need to be developed and made available. The Internet provides an ideal medium for the distribution of such educational tools".
Don Cossacks are credited with playing a significant part in repelling Napoleon's Invasion of Russia. Under the command of Count Matvey Ivanovich Platov, the Don Cossacks fought in a number of battles against the Grande Armée. In the Battle of Borodino, Don Cossacks made raids to the rear of the French Army. Platov commanded all the Cossack troops and successfully covered the retreat of the Russian Army to Moscow. The Don Cossacks distinguished themselves in subsequent campaigns, and took part in the capture of Paris. Napoleon is credited with declaring, "Cossacks are the finest light troops among all that exist. If I had them in my army, I would go through all the world with them."
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.
Solid NMN is commonly stored frozen at about minus 20 degrees Celsius, sealed against moisture, and protected from light. Solutions are typically prepared fresh because they can degrade more quickly. Specific storage conditions can vary by supplier and intended use.