The Experts below are selected from a list of 231 Experts worldwide ranked by ideXlab platform
Pietro Damiani - One of the best experts on this subject based on the ideXlab platform.
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ENZYMATIC SYNTHESIS OF STRUCTURED 1,2-DIACYL-sn-GLYCERO-3-PhosphocholineS FROM GLYCEROL-sn-3-Phosphocholine
Italian Journal of Food Science, 2008Co-Authors: Francesca Blasi, Lina Cossignani, Maria Stella Simonetti, Angela Maurizi, Pietro DamianiAbstract:The synthesis of structured 1,2-diacyl-sn-glycero-3-Phosphocholines (sn-1,2-PC) from glycerol-sn-3-Phosphocholine (GPC) was studied by means of enzymatic acylation reactions of the two free sn- positions of the glycerol backbone. Already after 22 h high conversions (absolute yields = 100%) of GPC to sn-2-lysophosphatidylcholines (sn-2-LPC) were achieved using Novozym 435, a lipase from Candida antarctica, selective for the sn-1 -position of GPC. In the second step the acylation of the sn-2-position of the sn-2-LPC was catalysed by phospholipase A 2 from hog pancreas and better acylation yields (40% absolute yield, corresponding to a relative yield of 70%, when the reactions were carried out at controlled water activity) were obtained if compared to analogous reactions reported in the literature. A chemical procedure to obtain structured sn-1,2-PC from sn-2-LPC was also used and better results (65% absolute yield, corresponding to a relative yield of 95%) were obtained in comparison with the enzymatic method.
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Enzymatic deacylation of l,2-diacyl-sn-glycero-3-Phosphocholines to sn-glycerol-3-Phosphocholine
Enzyme and Microbial Technology, 2006Co-Authors: Francesca Blasi, Lina Cossignani, Maria Stella Simonetti, M. Brutti, F. Ventura, Pietro DamianiAbstract:Abstract This research was undertaken to study the enzymatic deacylation of l,2-diacyl- sn -glycero-3-Phosphocholines ( sn -1,2-PC) to sn -glycerol-3-Phosphocholine (GPC); this compound could be an useful intermediate in the synthesis of “structured” sn -1,2-PC, after re-acylations of the two sn -positions of the glycerol backbone. The enzymatic reactions represent a valid alternative to the chemical deacylation that can be simply obtained in alkaline conditions. High conversion were achieved using a lipase selective for the sn -1-position of sn -1,2-PC (Lipozyme IM, from Mucor miehei ) together with a Phospholipase A 2 from hog pancreas, enzyme selective for the sn -2-position; the best results were obtained carrying out the enzymatic reaction in a microemulsion system.
Masayoshi Kinoshita - One of the best experts on this subject based on the ideXlab platform.
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Synthesis and properties of dimeric glycerophospholipid: 2,2'-dotriacontanedioylbis(1-palmitoyl-sn-glycero-3-Phosphocholine).
Journal of biochemistry, 1996Co-Authors: Kiyoshi Yamauchi, Katsuya Togawa, Masayoshi KinoshitaAbstract:2,2'-Dotriacontanedioylbis(1-palmitoyl-sn-glycero-3-Phosphocholine ) was synthesized chemically as a dimeric version of 1,2-dipalmitoyl-sn-glycero-3-Phosphocholine. Upon sonication in water, the bipolar lipid furnished a planar membrane of about 50 Angstrom thickness with gel-to-liquid crystalline phase transition constants of Tm = 53.4 degrees C, DeltaH = 20.9 kcal/mol, and DeltaS = 64.0 e.u. In an air/water interface, the lipid displayed unique surface pressure-surface area isotherms with a limiting area of 105-190 Angstrom/molecule at 10-20 degrees C. The lipid was a substrate of phospholipase A2 (Naja mocambique), which afforded 1-palmitoyl-sn-glycero-3-Phosphocholine and dotriacontanedioic acid as final products.
Richard I. Duclos - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of 1-palmitoyl-2-hexadecyl-sn-glycero-3-Phosphocholine (PHPC).
Chemistry and physics of lipids, 1993Co-Authors: Richard I. DuclosAbstract:Abstract A general method for the chirospecific synthesis of 1-acyl-2-alkyl- sn -glycero-3-Phosphocholines is described. 1-Palmitoyl-2-hexadecyl- sn -glycero-3-Phosphocholine (PHPC) was synthesized in 18% overall yield in ten steps via five new synthetic intermediates, and 1-acetyl-2-hexadecyl- sn -glycero-3-Phosphocholine (AHPC) was also synthesized. 1-Acyl-2-alkyl- sn -glycero-3-Phosphocholines, which have not been found to exist in nature, are ether lipid analogs of 1,2-diacyl- sn -glycero-3-Phosphocholines, which are important components of cell membranes. Biophysical studies of hydrated bilayers of PHPC will be of interest in probing the critical importance of the central region of these amphiphilic molecules to the molecular assemblies that are formed.
Francesca Blasi - One of the best experts on this subject based on the ideXlab platform.
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ENZYMATIC SYNTHESIS OF STRUCTURED 1,2-DIACYL-sn-GLYCERO-3-PhosphocholineS FROM GLYCEROL-sn-3-Phosphocholine
Italian Journal of Food Science, 2008Co-Authors: Francesca Blasi, Lina Cossignani, Maria Stella Simonetti, Angela Maurizi, Pietro DamianiAbstract:The synthesis of structured 1,2-diacyl-sn-glycero-3-Phosphocholines (sn-1,2-PC) from glycerol-sn-3-Phosphocholine (GPC) was studied by means of enzymatic acylation reactions of the two free sn- positions of the glycerol backbone. Already after 22 h high conversions (absolute yields = 100%) of GPC to sn-2-lysophosphatidylcholines (sn-2-LPC) were achieved using Novozym 435, a lipase from Candida antarctica, selective for the sn-1 -position of GPC. In the second step the acylation of the sn-2-position of the sn-2-LPC was catalysed by phospholipase A 2 from hog pancreas and better acylation yields (40% absolute yield, corresponding to a relative yield of 70%, when the reactions were carried out at controlled water activity) were obtained if compared to analogous reactions reported in the literature. A chemical procedure to obtain structured sn-1,2-PC from sn-2-LPC was also used and better results (65% absolute yield, corresponding to a relative yield of 95%) were obtained in comparison with the enzymatic method.
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Enzymatic deacylation of l,2-diacyl-sn-glycero-3-Phosphocholines to sn-glycerol-3-Phosphocholine
Enzyme and Microbial Technology, 2006Co-Authors: Francesca Blasi, Lina Cossignani, Maria Stella Simonetti, M. Brutti, F. Ventura, Pietro DamianiAbstract:Abstract This research was undertaken to study the enzymatic deacylation of l,2-diacyl- sn -glycero-3-Phosphocholines ( sn -1,2-PC) to sn -glycerol-3-Phosphocholine (GPC); this compound could be an useful intermediate in the synthesis of “structured” sn -1,2-PC, after re-acylations of the two sn -positions of the glycerol backbone. The enzymatic reactions represent a valid alternative to the chemical deacylation that can be simply obtained in alkaline conditions. High conversion were achieved using a lipase selective for the sn -1-position of sn -1,2-PC (Lipozyme IM, from Mucor miehei ) together with a Phospholipase A 2 from hog pancreas, enzyme selective for the sn -2-position; the best results were obtained carrying out the enzymatic reaction in a microemulsion system.
Kiyoshi Yamauchi - One of the best experts on this subject based on the ideXlab platform.
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Synthesis and properties of dimeric glycerophospholipid: 2,2'-dotriacontanedioylbis(1-palmitoyl-sn-glycero-3-Phosphocholine).
Journal of biochemistry, 1996Co-Authors: Kiyoshi Yamauchi, Katsuya Togawa, Masayoshi KinoshitaAbstract:2,2'-Dotriacontanedioylbis(1-palmitoyl-sn-glycero-3-Phosphocholine ) was synthesized chemically as a dimeric version of 1,2-dipalmitoyl-sn-glycero-3-Phosphocholine. Upon sonication in water, the bipolar lipid furnished a planar membrane of about 50 Angstrom thickness with gel-to-liquid crystalline phase transition constants of Tm = 53.4 degrees C, DeltaH = 20.9 kcal/mol, and DeltaS = 64.0 e.u. In an air/water interface, the lipid displayed unique surface pressure-surface area isotherms with a limiting area of 105-190 Angstrom/molecule at 10-20 degrees C. The lipid was a substrate of phospholipase A2 (Naja mocambique), which afforded 1-palmitoyl-sn-glycero-3-Phosphocholine and dotriacontanedioic acid as final products.
