The Experts below are selected from a list of 294 Experts worldwide ranked by ideXlab platform
Yashwant D. Vankar - One of the best experts on this subject based on the ideXlab platform.
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a concise route to Shikimic Acid and 5 epi Shikimic Acid and their enantiomers via barbier reaction and ring closing metathesis
Tetrahedron Letters, 2009Co-Authors: Pavan K Kancharla, Venkata Ramana Doddi, Hariprasad Kokatla, Yashwant D. VankarAbstract:A simple route for the synthesis of naturally occurring (-)-Shikimic Acid, (-)-5-epi-Shikimic Acid, and their enantiomers from D-ribose-derived enantiomeric aldehydes 8a and 8b by employing Barbier reaction and ring-closing metathesis as key steps has been developed.
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A concise route to (-)-Shikimic Acid and (-)-5-epi-Shikimic Acid, and their enantiomers via Barbier reaction and ring-closing metathesis
Tetrahedron Letters, 2009Co-Authors: Pavan K Kancharla, Venkata Ramana Doddi, Hariprasad Kokatla, Yashwant D. VankarAbstract:A simple route for the synthesis of naturally occurring (-)-Shikimic Acid, (-)-5-epi-Shikimic Acid, and their enantiomers from D-ribose-derived enantiomeric aldehydes 8a and 8b by employing Barbier reaction and ring-closing metathesis as key steps has been developed.
Chunlan Ban - One of the best experts on this subject based on the ideXlab platform.
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Separation and Purification of (−)-Shikimic Acid and (−)-Quinic Acid by the Phase Diagrams of the Ternary System of (−)-Shikimic Acid + (−)-Quinic Acid + H2O and the Quaternary System of (−)-Shikimic Acid + (−)-Quinic Acid + Ethanol (φ ∼ 50%,φ ∼ 75%)
Industrial & Engineering Chemistry Research, 2015Co-Authors: Xinying Hao, Qiang Huang, Guopeng Shen, Chunlan BanAbstract:The solid–liquid phase equilibrium for the ternary system of (−)-Shikimic Acid + (−)-Quinic Acid + H2O and the quaternary system of (−)-Shikimic Acid + (−)-Quinic Acid + Ethanol (φ ∼ 50%,φ ∼ 75%) + H2O was measured at T = 298.15, 318.15, 333.15, 348.15 K, and mutual solubility was obtained. Three variable-temperature phase diagrams were constructed according to the experimental solubility. In the phase diagrams, there were in all one invariant point, two univariant curves, and two crystallization regions corresponding to (−)-Shikimic Acid and (−)-Quinic Acid at each temperature in the studied system. The crystallization regions of the pure two solids increase with a decrease in temperature. The variable-temperature diagrams for the quaternary system of (−)-Shikimic Acid + (−)-Quinic Acid + Ethanol (φ ∼ 50%) + H2O can be used for effective separation and purification of (−)-Shikimic Acid and (−)-Quinic Acid. Meanwhile, the solid + liquid phase equilibrium data can be used for the separation process of (−)-...
Thomas Poon - One of the best experts on this subject based on the ideXlab platform.
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liquidambar styraciflua a renewable source of Shikimic Acid
Tetrahedron Letters, 2008Co-Authors: Liza B Enrich, Ashley Mohadjer, Chrystal F Eller, Scott M Newman, Michael Fujinaka, Kathryn R. Matthias, Margaret L Scheuermann, Thomas PoonAbstract:Abstract An isolation procedure is presented that yields 2.4–3.7% w/w pure Shikimic Acid from the seeds of Liquidambar styraciflua (Sweetgum). Shikimic Acid, the starting material in the commercial synthesis of the antiviral agent oseltamivir and an important intermediate in the biosynthesis of aromatic amino Acids in plants, was found by HPLC to be abundant in the granular, aborted seeds (6.5% w/w) while present only in small amounts in the developed, fertile seeds (0.14% w/w). This extraction technique makes L. styraciflua , which is found in 40 states of the continental US, a potential renewable source of this important natural product.
Uttam Chand Banerjee - One of the best experts on this subject based on the ideXlab platform.
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Studies on the production of Shikimic Acid using the aroK knockout strain of Bacillus megaterium.
World journal of microbiology & biotechnology, 2016Co-Authors: Saptarshi Ghosh, Utpal Mohan, Uttam Chand BanerjeeAbstract:Shikimic Acid has various pharmaceutical and industrial applications. It is the sole chemical building block for the antiviral drug oseltamivir (Tamiflu®) and one of the potent pharmaceutical intermediates with three chiral centres. Here we report a modified strain of Bacillus megaterium with aroK (shikimate kinase) knock out to block the aromatic biosynthetic pathway downstream of Shikimic Acid. Homologous recombination based gene disruption approach was used for generating aroK knock out mutant of B. megaterium. Shake flask cultivation showed Shikimic Acid yield of 2.98 g/L which is ~6 times more than the wild type (0.53 g/L). Furthermore, the shikimate kinase activity was assayed and it was 32 % of the wild type. Effect of various carbon sources on the production of Shikimic Acid was studied and fructose (4 %, w/v) was found to yield maximum Shikimic Acid (4.94 g/L). The kinetics of growth and Shikimic Acid production by aroK knockout mutant was studied in 10 L bioreactor and the yield of Shikimic Acid had increased to 6 g/L which is ~12 fold higher over the wild type. It is evident from the results that aroK gene disruption had an immense effect in enhancing the Shikimic Acid production.
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Generation of aroE overexpression mutant of Bacillus megaterium for the production of Shikimic Acid.
Microbial cell factories, 2015Co-Authors: Saptarshi Ghosh, Uttam Chand BanerjeeAbstract:Shikimic Acid, the sole chemical building block for the antiviral drug oseltamivir (Tamiflu®), is one of the potent pharmaceutical intermediates with three chiral centers. Here we report a metabolically engineered recombinant Bacillus megaterium strain with aroE (shikimate dehydrogenase) overexpression for the production of Shikimic Acid. In a 7 L bioreactor, 4.2 g/L Shikimic Acid was obtained using the recombinant strain over 0.53 g/L with the wild type. The enhancement of total shikimate dehydrogenase activity was 2.13-fold higher than the wild type. Maximum yield of Shikimic Acid (12.54 g/L) was obtained with fructose as carbon source. It was isolated from the fermentation broth using amberlite IRA-400 resin and 89 % purity of the product was achieved. This will add up a new organism in the armory for the fermentation based production which is better over plant based extraction and chemical synthesis of Shikimic Acid.
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Microbial transformation of quinic Acid to Shikimic Acid by Bacillus megaterium
Bioresources and Bioprocessing, 2014Co-Authors: Saptarshi Ghosh, Harish Pawar, Omkar Pai, Uttam Chand BanerjeeAbstract:Biotransformation of quinic Acid to Shikimic Acid was attempted using whole cells of Bacillus megaterium as a biocatalyst. Physico-chemical parameters such as temperature (37°C), pH (7.0), agitation (200 rpm), substrate (5 mM) and cell mass concentrations (200 kg/m 3) and reaction time (3 h) were found optimum to enhance the bioconversion. Maximum conversion (89%) of quinic Acid to Shikimic Acid was achieved using the above optimized parameters. Shikimic Acid was extracted from the reaction mixture by a pH-dependent method and maximum recovery (76%) was obtained with petroleum ether. Biotransformation of quinic Acid to Shikimic Acid seems to be a better alternative over its fermentative production.
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Production of Shikimic Acid
Biotechnology advances, 2012Co-Authors: Saptarshi Ghosh, Yusuf Chisti, Uttam Chand BanerjeeAbstract:Shikimic Acid is a key intermediate for the synthesis of the antiviral drug oseltamivir (Tamiflu®). Shikimic Acid can be produced via chemical synthesis, microbial fermentation and extraction from certain plants. An alternative production route is via biotransformation of the more readily available quinic Acid. Much of the current supply of Shikimic Acid is sourced from the seeds of Chinese star anise (Illicium verum). Supply from star anise seeds has experienced difficulties and is susceptible to vagaries of weather. Star anise tree takes around six-years from planting to bear fruit, but remains productive for long. Extraction and purification from seeds are expensive. Production via fermentation is increasing. Other production methods are too expensive, or insufficiently developed. In the future, production in recombinant microorganisms via fermentation may become established as the preferred route. Methods for producing Shikimic Acid are reviewed.
Pavan K Kancharla - One of the best experts on this subject based on the ideXlab platform.
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a concise route to Shikimic Acid and 5 epi Shikimic Acid and their enantiomers via barbier reaction and ring closing metathesis
Tetrahedron Letters, 2009Co-Authors: Pavan K Kancharla, Venkata Ramana Doddi, Hariprasad Kokatla, Yashwant D. VankarAbstract:A simple route for the synthesis of naturally occurring (-)-Shikimic Acid, (-)-5-epi-Shikimic Acid, and their enantiomers from D-ribose-derived enantiomeric aldehydes 8a and 8b by employing Barbier reaction and ring-closing metathesis as key steps has been developed.
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A concise route to (-)-Shikimic Acid and (-)-5-epi-Shikimic Acid, and their enantiomers via Barbier reaction and ring-closing metathesis
Tetrahedron Letters, 2009Co-Authors: Pavan K Kancharla, Venkata Ramana Doddi, Hariprasad Kokatla, Yashwant D. VankarAbstract:A simple route for the synthesis of naturally occurring (-)-Shikimic Acid, (-)-5-epi-Shikimic Acid, and their enantiomers from D-ribose-derived enantiomeric aldehydes 8a and 8b by employing Barbier reaction and ring-closing metathesis as key steps has been developed.