Derivatization of Chiral Amino Acids in Supercritical Carbon Dioxide

Highly enantioselective conversion of dienamides into cyclic α-amino acids can be achieved by a single-pot, tandem hydrogenation–hydroformylation–cyclization–elimination sequence using a single catalyst and supercritical carbon dioxide (scCO2) as the reaction solvent at total pressures significantly lower than those previously reported for related hydrogenation and hydroformylation reactions.

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Studies on proteins and amino acids exposed to supercritical carbon dioxide extraction conditions

Food Chemistry ◽

10.1016/0308-8146(84)90002-5 ◽

1984 ◽

Vol 15 (3) ◽

pp. 175-190 ◽

Cited By ~ 35

Author(s):

Jürgen K.P. Weder

Keyword(s):

Carbon Dioxide ◽

Amino Acids ◽

Supercritical Carbon Dioxide ◽

Supercritical Carbon Dioxide Extraction ◽

Carbon Dioxide Extraction ◽

Supercritical Carbon

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Solubility of N-CBZ derivatised amino acids in supercritical carbon dioxide

The Journal of Supercritical Fluids ◽

10.1016/j.supflu.2003.07.005 ◽

2004 ◽

Vol 30 (2) ◽

pp. 119-125 ◽

Cited By ~ 14

Author(s):

N. Vedaraman ◽

G. Brunner ◽

C. Srinivasa Kannan ◽

B.V. Ramabrahmam ◽

P.G. Rao

Keyword(s):

Carbon Dioxide ◽

Amino Acids ◽

Supercritical Carbon Dioxide ◽

Supercritical Carbon

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Solubility Modeling of N-CBZ Derivatised Amino Acids in Supercritical Carbon Dioxide

International Journal of Analytical Mass Spectrometry and Chromatography ◽

10.4236/ijamsc.2014.22006 ◽

2014 ◽

Vol 02 (02) ◽

pp. 52-63 ◽

Cited By ~ 1

Author(s):

N. Vedaraman ◽

Pravin Gadkari ◽

Balaraman Manohar ◽

K. V. Sandhya ◽

Gerd Brunner ◽

...

Keyword(s):

Carbon Dioxide ◽

Amino Acids ◽

Supercritical Carbon Dioxide ◽

Supercritical Carbon

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Mackerel Trypsin Purified from Defatted Viscera by Supercritical Carbon Dioxide

Journal of Amino Acids ◽

10.4061/2011/728082 ◽

2011 ◽

Vol 2011 ◽

pp. 1-7 ◽

Cited By ~ 3

Author(s):

Byung-Soo Chun ◽

Hideki Kishimura ◽

Sitthipong Nalinanon ◽

Sappasith Klomklao ◽

Soottawat Benjakul

Keyword(s):

Carbon Dioxide ◽

Amino Acids ◽

Molecular Weight ◽

Methyl Ester ◽

Supercritical Carbon Dioxide ◽

Organic Solvent ◽

Trypsin Inhibitor ◽

Calcium Ion ◽

Sds Page ◽

Supercritical Carbon

Viscera of mackerel (Scomber sp.) were defatted by supercritical carbon dioxide (SCO2) treatment. Trypsin (SC-T) was then extracted from the defatted powder and purified by a series of chromatographies including Sephacryl S-200 and Sephadex G-50. The purified SC-T was nearly homogeneous on SDS-PAGE, and its molecular weight was estimated as approximately 24,000 Da. N-terminal twenty amino acids sequence of SC-T was IVGGYECTAHSQPHQVSLNS. The specific trypsin inhibitors, soybean trypsin inhibitor and TLCK, strongly inhibited the activities of SC-T. The pH and temperature optimums of SC-T were at around pH 8.0 and , respectively, using Nα-p-tosyl-L-arginine methyl ester as a substrate. The SC-T was unstable below pH 5.0 and above , and it was stabilized by calcium ion. These enzymatic characteristics of SC-T were the same as those of other fish trypsins, especially spotted mackerel (S. borealis) trypsin, purified from viscera defatted by acetone. Therefore, we concluded that the SCO2 defatting process is useful as a substitute for organic solvent defatting process.

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Extraction of amino acids using supercritical carbon dioxide forin situastrobiological applications

International Journal of Astrobiology ◽

10.1017/s147355041800006x ◽

2018 ◽

Vol 18 (2) ◽

pp. 102-111 ◽

Cited By ~ 2

Author(s):

Marlen Menlyadiev ◽

Bryana L. Henderson ◽

Fang Zhong ◽

Ying Lin ◽

Isik Kanik

Keyword(s):

Mass Spectrometry ◽

Carbon Dioxide ◽

Amino Acids ◽

Supercritical Carbon Dioxide ◽

Elevated Temperatures ◽

Pure Water ◽

Space Applications ◽

Water Solvent ◽

Martian Regolith ◽

Supercritical Carbon

AbstractThe detection of organic molecules that are indicative of past or present biological activity within the Solar System bodies and beyond is a key research area in astrobiology. Mars is of particular interest in this regard because of evidence of a (perhaps transient) warm and wet climate in its past. To date, space missions to Mars have primarily used pyrolysis technique to extract organic compounds from the Martian regolith, but it has not enabled a clear detection of unaltered native Martian organics. The elevated temperatures required for pyrolysis extraction can cause native Martian organics to react with perchlorate salts in the regolith, possibly resulting in the chlorohydrocarbons that have been detected by mass spectrometry, a commonly usedin situtechnique for space applications. Supercritical carbon dioxide (SCCO2) extraction technique is a powerful alternative to pyrolysis that may be capable of extracting and delivering unaltered native organic species to an analyser. In this study, we report the SCCO2extraction of unaltered amino acids (AAs) with simple laboratory analyses of extracts by capillary electrophoresis laser-induced fluorescence (CE/LIF) and liquid chromatography with mass spectrometry (LC/MS) techniques. The extraction efficiencies of several representative AAs using SCCO2with small amounts of pure water (~1–5%) as a co-solvent were determined. Glass beads were used as a model substrate to examine the effects of several experimental parameters and Johnson Space Center (JSC) Mars-1A Martian regolith simulant was used to study the effect of complex matrix on extraction efficiencies. With optimized experimental conditions (75C and 5% of water), extraction efficiencies from doped JSC Mars-1A were found to be ~40% for glycine, alanine and serine and ~10% for lysine. Extraction of native organics from undoped JSC Mars-1A suggests that SCCO2/water solvent system can extract both organics extractable with pure SCCO2and those extractable with pure water. Additionally, species not extracted by either pure SCCO2or pure water were extracted with SCCO2/water solvent. Despite the preliminary nature of this work, it paves the path for more comprehensive extraction studies of astrobiologically relevant samples with thorough analyses of resulting extracts.

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