TY - JOUR
T1 - Cat's claw oxindole alkaloid isomerization induced by common extraction methods
AU - Kaiser, Samuel
AU - Verza, Simone Gasparin
AU - Moraes, Renata Cougo
AU - de Resende, Pedro Ernesto
AU - Pavei, Cabral
AU - Ortega, George González
AU - Barreto, Fabiano
PY - 2013/8/8
Y1 - 2013/8/8
N2 - Cat's claw oxindole alkaloids are prone to isomerization in aqueous solution. However, studies on their behavior in extraction processes are scarce. This paper addressed the issue by considering five commonly used extraction processes. Unlike dynamic maceration (DM) and ultrasound-assisted extraction, substantial isomerization was induced by static maceration, turbo-extraction and reflux extraction. After heating under reflux in DM, the kinetic order of isomerization was established and equations were fitted successfully using a four-parameter Weibull model (R² > 0.999). Different isomerization rates and equilibrium constants were verified, revealing a possible matrix effect on alkaloid isomerization.
AB - Cat's claw oxindole alkaloids are prone to isomerization in aqueous solution. However, studies on their behavior in extraction processes are scarce. This paper addressed the issue by considering five commonly used extraction processes. Unlike dynamic maceration (DM) and ultrasound-assisted extraction, substantial isomerization was induced by static maceration, turbo-extraction and reflux extraction. After heating under reflux in DM, the kinetic order of isomerization was established and equations were fitted successfully using a four-parameter Weibull model (R² > 0.999). Different isomerization rates and equilibrium constants were verified, revealing a possible matrix effect on alkaloid isomerization.
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84884807468&partnerID=MN8TOARS
U2 - 10.1590/S0100-40422013000600012
DO - 10.1590/S0100-40422013000600012
M3 - Article
VL - 36
SP - 808
EP - 814
JO - Quimica Nova
JF - Quimica Nova
IS - 6
ER -