1,2,3,4,6-Pentagalloyl glucose

From Wikipedia, the free encyclopedia
Jump to: navigation, search
For other uses, see Pentagalloyl glucose.
1,2,3,4,6-Pentagalloyl glucose
Chemical structure of pentagalloyl glucose
Identifiers
CAS number 14937-32-7 N=
PubChem 65238
ChemSpider 58735 YesY
ChEBI CHEBI:18082 YesY
ChEMBL CHEMBL382408 YesY
Jmol-3D images Image 1
Properties
Molecular formula C41H32O26
Molar mass 940.67 g/mol
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
 N (verify) (what is: YesY/N?)
Infobox references

1,2,3,4,6-Pentagalloyl glucose is the pentahydroxy gallic acid ester of glucose. It is the common precursor of gallotannins and the related ellagitannins.[1]

Pentagalloyl glucose can precipitate proteins[2] including human salivary α-amylase.[3]

It may also be used in radioprotection.[4]

Natural occurrences[edit]

1,2,3,4,6-Pentagalloyl glucose can be found in Punica granatum, the pomegranate,[5] in Elaeocarpus sylvestris[4] or in Rhus typhina, the staghorn sumac.[6]

Biosynthesis[edit]

The enzyme beta-glucogallin-tetrakisgalloylglucose O-galloyltransferase uses 1-O-galloyl-beta-D-glucose and 1,2,3,6-tetrakis-O-galloyl-beta-D-glucose to produce D-glucose and Pentagalloyl glucose.

Metabolism[edit]

Metabolism of ellagitannins[edit]

Tellimagrandin II, first of all ellagitannins, forms from pentagalloyl glucose by oxydative dehydrogenation and coupling of 2 galloyl groups.

β-glucogallin: 1,2,3,4,6-pentagalloyl-β-d-glucose galloyltransferase is an enzyme found in the leaves of Rhus typhina, the staghorn sumac, that catalyses the galloylation of 1,2,3,4,6-penta-O-galloyl-β-d-glucose to 3-O-digalloyl-1,2,4,6-tetra-O-galloyl-β-d-glucose (hexa-galloylglucose).[6]

Chemistry[edit]

Pentagalloyl glucose can undergo oxidation reactions which are depending on the pH.[7]

References[edit]

  1. ^ Biosynthesis of gallotannins: β-Glucogallin-dependent formation of 1,2,3,4,6-pentagalloylglucose by enzymatic galloylation of 1,2,3,6-tetragalloylglucose. Cammann J., Denzel K., Schilling G. and Gross G. G., Archives of Biochemistry and Biophysics, Volume 273, Issue 1, 15 August 1989, Pages 58-63
  2. ^ Mechanisms of protein precipitation for two tannins, pentagalloyl glucose and epicatechin16 (4→8) catechin (procyanidin). Hagerman A. E., Rice M. E. and Ritchard N. T., Journal of agricultural and food chemistry, 1998, vol. 46, no7, pp. 2590-2595
  3. ^ Evidence for pentagalloyl glucose binding to human salivary α-amylase through aromatic amino acid residues. Gyöngyi Gyémánt, Ágnes Zajácz, Bálint Bécsi, Chandran Ragunath, Narayanan Ramasubbu, Ferenc Erdődi, Gyula Batta and Lili Kandra, Biochimica et Biophysica Acta (BBA) - Proteins & Proteomics, Volume 1794, Issue 2, February 2009, pp. 291-296
  4. ^ a b Elaeocarpus sylvestris modulates gamma-ray-induced immunosuppression in mice: implications in radioprotection. Park E, Lee NH, Baik JS and Jee Y, Phytother Res., August 2008, volume 22, issue 8, pages 1046-1051, doi:10.1002/ptr.2430, PubMed
  5. ^ Punicafolin, an ellagitannin from the leaves of Punica granatum. Takashi Tanaka, Gen-Ichiro Nonaka and Itsuo Nishioka, Phytochemistry, Volume 24, Issue 9, 1985, Pages 2075–2078, doi:10.1016/S0031-9422(00)83125-8
  6. ^ a b Gallotannin biosynthesis: purification of β-glucogallin: 1,2,3,4,6-pentagalloyl-β-d-glucose galloyltransferase from sumac leaves. Ruth Niemetz and Georg G Gross, Phytochemistry, Volume 49, Issue 2, 28 September 1998, pages 327-332, doi:10.1016/S0031-9422(98)00014-4
  7. ^ Reaction pH and protein affect the oxidation products of β-pentagalloyl glucose. Yumin C. and Hagerman A.E., Free radical research, 2005, vol. 39, no2, pp. 117-124