Chemistry:S-Allylcysteine

From HandWiki
S-Allyl cysteine
S-Allyl cysteine
S-Allyl cysteine
Names
IUPAC name
(R)-2-Amino-3-prop-2-enylsulfanylpropanoic acid
Other names
S-2-propenyl-L-cysteine; S-allyl-laevo-cysteine; S-allylcysteine
Identifiers
3D model (JSmol)
Abbreviations SAC
ChEBI
ChemSpider
UNII
Properties
C6H11NO2S
Molar mass 161.22 g/mol
Density 1.191 ± 0.06 g/cm3
Melting point 219 to 220 °C (426 to 428 °F; 492 to 493 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)
Infobox references

S-Allylcysteine (SAC) is an organosulfur compound that has the formula HO
2CCH(NH
2)CH
2SCH
2C=CH
2. It is the S-allylated derivative of the amino acid cysteine. As such only the L-enantiomer is significant biologically. SAC constituent of aged garlic. A number of related compounds are found in garlic, including the disulfide S-"allylmercaptocysteine" (SAMC, HO
2CCH(NH
2)CH
2SSCH
2C=CH
2) and γ-glutamyl-S-allylcysteine" (GSAC).[1] Allylcysteine is of interest for its potential medicinal properties.[2] and as a chemopreventive.[3]

Occurrence and formation

SAC is present in low concentrations in fresh garlic but accumulates significantly during controlled ageing. The conversion of γ-glutamyl-S-allylcysteine (GSAC) to SAC occurs progressively over extended ageing periods, typically ranging from 10 to 20 months under controlled conditions.[4] This accumulation is one reason aged garlic extract preparations have a substantially different compound profile compared to raw garlic, garlic powder, or garlic oil.[5]

Pharmacokinetics

SAC is water-soluble and demonstrates substantially higher bioavailability compared to allicin and allicin-derived compounds, which are chemically unstable and degrade rapidly following formation.[6] SAC has been detected in human plasma following oral administration of aged garlic extract preparations, suggesting meaningful systemic absorption.[7]

Use as a standardisation marker

Because SAC concentration in aged garlic extract is predictably related to ageing duration and conditions, it is commonly used as a quality and standardisation marker in both research preparations and commercial aged garlic extract supplements. Standardisation for SAC content allows for more consistent comparisons across studies and products than is possible with raw garlic or allicin-based preparations.[8]

Cardiovascular research

SAC has been investigated in the context of cardiovascular health, primarily through studies using standardised aged garlic extract preparations in which SAC serves as a marker compound. Multiple randomised controlled trials have examined aged garlic extract in relation to blood pressure markers, arterial stiffness and vascular function, typically over study periods of 8 to 24 weeks.[9] A systematic review and meta-analysis of randomised controlled trials concluded that aged garlic extract preparations were associated with reductions in systolic and diastolic blood pressure in adults with elevated baseline values, though the authors noted variability across studies.[10]

Research has also examined aged garlic extract in relation to arterial stiffness and endothelial function. One randomised controlled trial found reductions in central blood pressure and pulse wave velocity — markers of arterial stiffness — following 12 weeks of aged garlic extract supplementation in adults with uncontrolled hypertension.[11]

These findings are specific to standardised aged garlic extract preparations used under controlled research conditions and should not be generalised to raw garlic or other garlic supplement forms.

See also

  • Alliin, the S-oxide of allyl cysteine

References

  1. ↑ Fujii, Takuto; Matsutomo, Toshiaki; Kodera, Yukihiro (2018). "Changes of S-Allylmercaptocysteine and γ-Glutamyl-S-allylmercaptocysteine Contents and Their Putative Production Mechanisms in Garlic Extract during the Aging Process". Journal of Agricultural and Food Chemistry 66 (40): 10506–10512. doi:10.1021/acs.jafc.8b02541. PMID 30226990. Bibcode: 2018JAFC...6610506F. 
  2. ↑ "Cholesterol-lowering effect of garlic extracts and organosulfur compounds: human and animal studies". Journal of Nutrition 131 (3s): 989S–93S. 2001. doi:10.1093/jn/131.3.989S. PMID 11238803. 
  3. ↑ Arora, Annu; Tripathi, Chitra; Shukla, Yogeshwer (2005). "Garlic and its organosulfides as potential chemopreventive agents: a review". Current Cancer Therapy Reviews 1 (2): 199–205. doi:10.2174/1573394054021772. 
  4. ↑ Amagase, Harunobu (2006). "Clarifying the real bioactive constituents of garlic". Journal of Nutrition 136 (3): 716S–725S. doi:10.1093/jn/136.3.716S. PMID 16484553. 
  5. ↑ Fujii, Takuto; Matsutomo, Toshiaki; Kodera, Yukihiro (2018). "Changes of S-Allylmercaptocysteine and γ-Glutamyl-S-allylmercaptocysteine Contents and Their Putative Production Mechanisms in Garlic Extract during the Aging Process". Journal of Agricultural and Food Chemistry 66 (40): 10506–10512. doi:10.1021/acs.jafc.8b02541. PMID 30226990. Bibcode: 2018JAFC...6610506F. 
  6. ↑ Nagae, S; Ushijima, M; Hatono, S; Imai, J; Kasuga, S; Matsuura, H; Itakura, Y; Fuwa, T (1994). "Pharmacokinetics of the garlic compound S-allylcysteine". Planta Medica 60 (3): 214–217. doi:10.1055/s-2006-957685. PMID 8073846. 
  7. ↑ Amagase, Harunobu (2006). "Clarifying the real bioactive constituents of garlic". Journal of Nutrition 136 (3): 716S–725S. doi:10.1093/jn/136.3.716S. PMID 16484553. 
  8. ↑ Amagase, Harunobu (2006). "Clarifying the real bioactive constituents of garlic". Journal of Nutrition 136 (3): 716S–725S. doi:10.1093/jn/136.3.716S. PMID 16484553. 
  9. ↑ Ried, Karin; Travica, Nikolaj; Sali, Avni (2016). "Aged garlic extract reduces blood pressure in hypertensives: a dose–response trial". European Journal of Clinical Nutrition 70 (6): 762–766. doi:10.1038/ejcn.2015.183. PMID 26511579. 
  10. ↑ Ried, Karin; Frank, Oliver R; Stocks, Nigel P; Fakler, Peter; Sullivan, Thomas (2008). "Effect of garlic on blood pressure: A systematic review and meta-analysis". BMC Cardiovascular Disorders 8. doi:10.1186/1471-2261-8-13. PMID 18554422. 
  11. ↑ Ried, Karin; Travica, Nikolaj; Sali, Avni (2016). "Aged garlic extract reduces blood pressure in hypertensives: a dose–response trial". European Journal of Clinical Nutrition 70 (6): 762–766. doi:10.1038/ejcn.2015.183. PMID 26511579. 



Retrieved from "https://handwiki.org/wiki/index.php?title=Chemistry:S-Allylcysteine&oldid=4438813"