Direct and simultaneous analysis of lipase-catalyzed hydrolysis of high-oleic oil model by chiral stationary phase HPLC-ELSD

Kinetic modeling of lipase-catalysed hydrolysis of triacylglycerol in a reverse micelle system for the determination of integral stereoselectivity

“…6C). 19,20 In all cases, the best fit of the models are in good agreement with the experimental results with satisfactory values of determination coefficient (R 2 ), which were calculated to be 0.96, 0.98, and 0.99 for PPL, CVL, and PFL, respectively.…”

“…The hydrolysis of TOG in a reverse micelle was conducted as previously described 20 with a slight modification. Lipase was solubilised in 50 mM Tris–HCl buffer (pH 7.7, PPL; pH 8.0, CVL and PFL) and vigorously mixed with AOT/isooctane for 1 min to obtain a transparent mixture, which indicates the formation of a reverse micelle.…”

“…The substrate and products (TOG, DOG isomers, MOG isomers, and OA) were simultaneously analysed using an HPLC-ELSD device (Waters Alliance e2695 separation module, Waters Co., Milford, MA, USA; Alltech ELSD 2000 instrument, Alltech Co., Deerfield, MA, USA) equipped with a chiral stationary phase column (CHIRALPAK IA [amylose tris(3,5-dimethylphenylcarbamate) immobilised on 5 μm silica gel, 250 × 4.6 mm]; Daicel Chemical Ind., Osaka, Japan) as previously described. 20 At various time points up to 24 h, aliquots (50 and 100 μL) of the reactant were collected and diluted with 1.05 and 1.15 mL acetonitrile–acetone (90 : 10, v/v), respectively. Then the mixtures were vortexed for 30 s to obtain a transparent phase and filtered through a 0.45 μm PTFE syringe filter.…”

“…1, we previously proposed the concept of 'integral stereoselectivity' and developed a chromatographic method for analyses. 19,20 Based on a time-course of TAG, FFA, regioisomers, and enantiomers of DAG (i.e., 1,2-sn-, 1,3-sn-, and 2,3-sn-DAG) and MAG (i.e., 1-sn-, 2-sn-, and 3-sn-MAG) obtained with this analytical method, in this study, the integral stereoselectivity of lipase was quantified as a kinetic constant for each step of the reaction. This is the first presentation of a kinetic model describing integral stereoselectivities of lipases.…”

“…1, we previously proposed the concept of ‘integral stereoselectivity’ and developed a chromatographic method for analyses. 19,20 Based on a time-course of TAG, FFA, regioisomers, and enantiomers of DAG ( i.e. , 1,2- sn -, 1,3- sn -, and 2,3- sn -DAG) and MAG ( i.e.…”