Editing Tannin (section)

== History ==
[[Ellagic acid]], [[gallic acid]], and [[pyrogallic acid]] were first discovered by chemist [[Henri Braconnot]] in 1831.<ref name="Grasser">{{Cite book|url=https://archive.org/details/synthetictannins032496mbp|title=Synthetic Tannins|isbn=978-1-4067-7301-9|last1=Grasser|first1=Georg|year=1922|others=F. G. A. Enna. (trans.)|publisher=Read Books }}</ref>{{rp|20}} [[Julius Löwe]] was the first person to synthesize ellagic acid by heating [[gallic acid]] with [[arsenic acid]] or silver oxide.<ref name="Grasser" />{{rp|20}}<ref>{{cite journal |last=Löwe |title= |journal=Zeitschrift für Chemie |year=1868 |volume=4 |page=603}}</ref>

[[Maximilian Nierenstein]] studied natural phenols and tannins<ref>{{Cite journal
| last1 = Drabble | first1 = E.
| last2 = Nierenstein | first2 = M.
| title = On the Rôle of Phenols, Tannic Acids, and Oxybenzoic Acids in Cork Formation
| journal = Biochemical Journal
| volume = 2
| issue = 3
| pages = 96–102.1
| year = 1907
| pmid = 16742048
| pmc = 1276196
| doi = 10.1042/bj0020096
}}</ref> found in different plant species. Working with [[Arthur George Perkin]], he prepared [[ellagic acid]] from [[algarobilla]] and certain other [[fruit]]s in 1905.<ref>{{Cite journal | last1 = Perkin | first1 = A. G. | last2 = Nierenstein | first2 = M. | doi = 10.1039/CT9058701412 | title = CXLI – Some oxidation products of the hydroxybenzoic acids and the constitution of ellagic acid. Part I | journal = Journal of the Chemical Society, Transactions | volume = 87 | pages = 1412–1430 | year = 1905 | url = https://zenodo.org/record/1657036 }}</ref> He suggested its formation from [[galloyl]]-[[glycine]] by ''[[Penicillium]]'' in 1915.<ref>{{Cite journal
| last1 = Nierenstein | first1 = M.
| title = The Formation of Ellagic Acid from Galloyl-Glycine by ''Penicillium''
| journal = The Biochemical Journal
| volume = 9
| issue = 2
| pages = 240–244
| year = 1915
| pmid = 16742368
| pmc = 1258574
 | doi=10.1042/bj0090240
}}</ref> [[Tannase]] is an enzyme that Nierenstein used to produce m-[[digallic acid]] from [[gallotannin]]s.<ref>{{Cite journal
| last1 = Nierenstein | first1 = M.
| title = A biological synthesis of m-digallic acid
| journal = The Biochemical Journal
| volume = 26
| issue = 4
| pages = 1093–1094
| year = 1932
| pmid = 16744910
| pmc = 1261008
 | doi=10.1042/bj0261093
}}</ref> He proved the presence of [[catechin]] in [[cocoa bean]]s in 1931.<ref>{{Cite journal | last1 = Adam | first1 = W. B. | last2 = Hardy | first2 = F. | last3 = Nierenstein | first3 = M. | title = The Catechin of the Cacao Bean| journal = Journal of the American Chemical Society | volume = 53 | issue = 2 | pages = 727–728 | year = 1931 | doi = 10.1021/ja01353a041 | bibcode = 1931JAChS..53..727A }}</ref> He showed in 1945 that [[luteic acid]], a molecule present in the myrobalanitannin, a tannin found in the fruit of ''[[Terminalia chebula]]'', is an intermediary compound in the synthesis of [[ellagic acid]].<ref>{{Cite journal
| last1 = Nierenstein | first1 = M.
| last2 = Potter | first2 = J.
| title = The distribution of myrobalanitannin
| journal = The Biochemical Journal
| volume = 39
| issue = 5
| pages = 390–392
| year = 1945
| pmid = 16747927
| pmc  = 1258254
 | doi=10.1042/bj0390390
}}</ref>

At these times, molecule formulas were determined through [[combustion analysis]]. The discovery in 1943 by Martin and Synge of [[paper chromatography]] provided for the first time the means of surveying the phenolic constituents of plants and for their separation and identification. There was an explosion of activity in this field after 1945, including prominent work by [[Edgar Charles Bate-Smith]] and [[Tony Swain (chemist)|Tony Swain]] at [[Cambridge University]].<ref name="Haslam">{{cite journal|last=Haslam|first=Edwin|title=Vegetable tannins – Lessons of a phytochemical lifetime|journal=Phytochemistry|year=2007|issue=22–24|pages=2713–2721|doi=10.1016/j.phytochem.2007.09.009|pmid=18037145|volume=68|bibcode=2007PChem..68.2713H }}</ref>

In 1966, [[Edwin Haslam]] proposed a first comprehensive definition of plant polyphenols based on the earlier proposals of Bate-Smith, Swain and Theodore White, which includes specific structural characteristics common to all phenolics having a tanning property. It is referred to as the White–Bate-Smith–Swain–Haslam (WBSSH) definition.<ref>{{cite web|last=Quideau|first=Stéphane|url=http://www.groupepolyphenols.com/index.php?option=com_content&view=article&id=53&Itemid=59&b528026c36a38313c3bc0e90a25fbe0c=7012a845601d61b99d4b8fbc24b709de|title=Why bother with Polyphenols|publisher=Groupe Polyphenols|date=22 September 2009|access-date=21 August 2012|url-status=live|archive-url=https://web.archive.org/web/20120310221945/http://www.groupepolyphenols.com/index.php?option=com_content&view=article&id=53&Itemid=59&b528026c36a38313c3bc0e90a25fbe0c=7012a845601d61b99d4b8fbc24b709de|archive-date=10 March 2012|df=dmy-all}}{{self-published source|date=May 2011}}</ref>{{Self-published inline|date=May 2011}}