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Though many organisms synthesize their own vitamin C, the steps can be different in plants and mammals. Smirnoff concluded that “..little is known about many of the enzymes involved in ascorbate biosynthesis or about the factors controlling flux through the pathways". There is interest in finding
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Even today industrial methods for the production of ascorbic acid can be based on the
Reichstein process. In modern methods however, sorbose is directly oxidized with a platinum catalyst (developed by
253:. Glucose is converted to 2-keto-L-gulonic acid in two steps (via 2,4-diketo-L-gulonic acid intermediate) as compared to five steps in the traditional process.
242:(1908–2005) in 1942). This method avoids the use of protective groups. A side product with particular modification is 5-Keto-D-gluconic acid.
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alternatives to the
Reichstein process. Experiments suggest that genetically modified bacteria might be commercially usable.
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Direct oxidation of L-sorbose to 2-Keto-L-gulonic acid with molecular oxygen on
Platinum- and Palladium-based catalysts
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The microbial oxidation of sorbitol to sorbose is important because it provides the correct
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A shorter biotechnological synthesis of ascorbic acid was announced in 1988 by
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in 1934. The first commercially sold vitamin C product was either
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and his colleagues in 1933 while working in the laboratory of the
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Harold A. Wittcoff, Bryan G. Reuben, Jeffery S. Plotkin (2012).
165:) followed by heating with water gives the 2-Keto-L-gulonic acid
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that takes place in several steps. This process was devised by
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Microbial processes for ascorbic acid biosynthesis: a review
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to
Diacetone-L-sorbose (2,3:4,6−Diisopropyliden−α−L−sorbose)
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Biotechnological approaches for L-ascorbic acid production
277:. S. Hirzel Verlag Stuttgart; 24. überarb Auflage 2004,
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The use of microorganisms in L-ascorbic acid production
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Eine ergiebige
Synthese der L-Ascorbinsäure (C-Vitamin)
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http://www.chemieunterricht.de/dc2/asch2/a-synthe.htm
397:Hancock, Robert D. und Viola, Roberto. (2002):
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511:Der Schweizerische Weg zur Viamin-C-Synthese
102:under high temperature and high pressure.
294:Reichstein, T. und Grüssner, A. (1934):
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219:This process was patented and sold to
139:groups in sorbose by formation of the
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273:Wittko Francke und Wolfgang Walter:
183:can also be prepared directly from
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275:Lehrbuch der Organischen Chemie
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494:10.1016/j.jbiotec.2006.01.010
422:10.1016/S0167-7799(02)01991-1
379:10.1016/s0083-6729(01)61008-2
35:method for the production of
460:10.1016/0141-0229(90)90159-N
363:L-ascorbic acid biosynthesis
347:Industrial Organic Chemicals
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349:. John Wiley & Sons,
235:from Hoffmann-La Roche.
67:The reaction steps are:
442:Enzyme Microb Technol.
403:Trends in Biotechnology
335:10.1006/jcat.1994.1336
247:Genencor International
176:with removal of water.
159:potassium permanganate
436:Boudrant, J. (1990):
367:Vitamins and Hormones
361:Smirnoff, Nicholas.
168:The final step is a
129:4-6 and 30 °C.
49:Tadeusz Reichstein
21:Reichstein process
526:Organic reactions
408:(7); S. 299–305;
329:(1), S. 199–211;
221:Hoffmann-La Roche
170:ring-closing step
155:Organic oxidation
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163:Diprogulic acid
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111:fermentation
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123:acetobacter
45:Nobel Prize
431:Literature
261:References
240:Kurt Heyns
215:Importance
133:protection
105:Microbial
373::241-66.
324:J. Catal.
172:or gamma
135:of the 4
107:oxidation
41:D-glucose
33:microbial
25:chemistry
520:Category
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469:(2006):
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318:(1994):
285:; S. 480
193:platinum
137:hydroxyl
100:catalyst
88:sorbitol
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233:Redoxon
147:and an
145:acetone
119:sorbose
80:glucose
47:winner
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473:. In:
467:et al.
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440:. In:
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401:. In:
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369:2001;
365:. In:
322:. In:
316:et al.
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225:Cebion
189:oxygen
141:acetal
96:nickel
57:Zürich
229:Merck
227:from
187:with
157:with
143:with
121:with
98:as a
94:with
90:, an
39:from
482:PMID
448:PMID
410:PMID
382:PMID
279:ISBN
249:and
191:and
161:(to
149:acid
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19:The
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456:doi
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127:pH
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115:L
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84:D
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