|Preferred IUPAC name
3D model (JSmol)
CompTox Dashboard (EPA)
|Molar mass||145.250 g·mol−1|
|Density||925 mg mL−1|
|Melting point||22 to 25 °C (72 to 77 °F; 295 to 298 K)|
|145 g L−1 (at 20 °C)|
|UV-vis (λmax)||260 nm|
Refractive index (nD)
|P280, P305+P351+P338, P310|
|Flash point||112 °C (234 °F; 385 K)|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Spermidine is a polyamine compound (C
3) found in ribosomes and living tissues and having various metabolic functions within organisms. It was originally isolated from semen.
Spermidine is an aliphatic polyamine. Spermidine synthase (SPDS) catalyzes its formation from putrescine. It is a precursor to other polyamines, such as spermine and its structural isomer thermospermine.
Spermidine synchronizes an array of biological processes, (such as Ca2+, Na+, K+ -ATPase) thus maintaining membrane potential and controlling intracellular pH and volume. Spermidine regulates biological processes, such as Ca2+ influx by glutamatergic N-methyl-d-aspartate receptor (NMDA receptor), which has been associated with nitric oxide synthase (NOS) and cGMP/PKG pathway activation and a decrease of Na+,K+-ATPase activity in cerebral cortex synaptosomes.
Spermidine is a longevity agent in mammals due to various mechanisms of action, which are just beginning to be understood. Autophagy is the main mechanism at the molecular level, but evidence has been found for other mechanisms, including inflammation reduction, lipid metabolism, and regulation of cell growth, proliferation, and death.
Spermidine is known to regulate plant growth, assisting the in vitro process of transcribing RNA, and inhibition of NOS. Also, spermidine is a precursor to other polyamines, such as spermine and thermospermine, some of which contribute to tolerance against drought and salinity in plants.
Spermidine has been tested and discovered to encourage hair shaft elongation and lengthen hair growth. Spermidine has also been found to “upregulate expression of the epithelial stem cell-associated keratins K15 and K19, and dose-dependently modulated K15 promoter activity in situ and the colony forming efficiency, proliferation and K15 expression of isolated human K15-GFP+ cells in vitro.”
Spermidine's known actions include:
Good dietary sources of spermidine are aged cheese, mushrooms, soy products, legumes, corn, and whole grains. Spermidine is plentiful in a Mediterranean diet. For comparison: The spermidine content in human seminal plasma varies between approx. 15 and 50 mg/L (mean 31 mg/L).
|notes & refs|
|Soybean, dried||207||Japanese |
|Cheddar, 1yr old||199|||
|Soybean, dried||128||German |
Note - spermidine content varies by source and age. See ref for details.
In grains, the endosperm contains most of the spermidine. One of the best known grain dietary sources is wheat germ, containing as much as 243 mg/kg.