959833-91-1Relevant academic research and scientific papers
The NMR tube bioreactor
Chatzikonstantinou, Alexandra V.,Tsiailanis, Antonis D.,Gerothanassis, Ioannis P.,Stamatis, Haralambos,Ravera, Enrico,Fragai, Marco,Luchinat, Claudio,Parigi, Giacomo,Tzakos, Andreas G.
, p. 71 - 101 (2020/01/03)
Enzymes are pliable systems and core cellular components allowing the performance of several processes. They can also be utilized as “green” synthetic factories to generate bioactive therapeutic, diagnostic or theranostic compounds. Methods to enable the mapping of enzyme substrates as well as the understanding of the interactions of the formed products with target proteins could be of importance. This chapter describes the utilization of the “NMR tube bioreactor” method. This method, carried out inside an NMR tube, can allow for the prediction of compounds that are able to serve as potential enzyme substrates, and also exploit the regioselectivity of the enzymatic reactions. Furthermore, it enables the real time monitoring of multiple-biotransformation products in the NMR tube without the need of fractionation or isolation of each individual component. Finally, it allows for the screening of the resulting biotransformation products as ligands for protein targets.
Unexpected enzyme-catalyzed regioselective acylation of flavonoid aglycones and rapid product screening
Kyriakou, Eleni,Primikyri, Alexandra,Charisiadis, Pantelis,Katsoura, Maria,Gerothanassis, Ioannis P.,Stamatis, Haralambos,Tzakos, Andreas G.
supporting information; experimental part, p. 1739 - 1742 (2012/04/23)
Unprecedented regioselective acylation of flavonoid aglycones was achieved using Candida antarctica lipase B (CALB). The rapid screening of product formation was performed by the use of the high resolution phenol-type OH 1H NMR spectral region recorded after the addition of picric acid.
Enzymatic acylation of flavonoids: Effect of the nature of the substrate, origin of lipase, and operating conditions on conversion yield and regioselectivity
Chebil, Latifa,Anthoni, Julie,Humeau, Catherine,Gerardin, Christine,Engasser, Jean-Marc,Ghoul, Mohamed
, p. 9496 - 9502 (2008/09/17)
The conversion yield at equilibrium, the initial rate, and the regioselectivity of the enzymatic acetylation of aglycone flavonoids (quercetin, naringenin, hesperetin, and chrysin) were investigated and compared to those obtained with a glycosylated one (isoquercitrin). The effects of a wide range of operating conditions were quantified. Fourier transform infrared spectrometry (FT-IR), NMR, and high performance liquid chromatography electrospray ionization mass spectrometry (HPLC-ESI-MS) analyses showed that for glycosylated flavonoids, in the presence of Candida antarctica (CAL-B), the acetylation occurred on the 2″-OH, 3″-OH, and 6″-OH of the glucose part, while with Pseudomonas cepacea lipase (PSL-C) acetylation takes place on 6″-OH of the sugar and 4′-OH of the B-ring. For aglycone flavonoids, the acetylation occurred only with PSL-C on 4′-OH, 3′-OH, and 7-OH hydroxyls. The conversion yield and the number and the relative proportions of the synthesized products were found dependent on the nature of the enzyme, the molar ratio, and the flavonoid structure. The initial rate was affected only by the origin of the enzyme.
