Chemiluminescence assay for catechin based on generation of hydrogen peroxide in basic solution
2002; Elsevier BV; Volume: 472; Issue: 1-2 Linguagem: Inglês
10.1016/s0003-2670(02)00982-0
ISSN1873-4324
AutoresHidetoshi Arakawa, Mahina Kanemitsu, Noriko Tajima, Masako Maeda,
Tópico(s)Dye analysis and toxicity
ResumoWe have determined that the catechin group in basic solution efficiently produces hydrogen peroxide; moreover, a highly sensitive analysis methodology was developed to measure catechin employing a peroxalate chemiluminescence detection system. Identification of hydrogen peroxide generated by catechin was determined by ESR as well as peroxalate chemiluminescence using catalase and SOD. As a result, catechin-generated superoxide by electron reduction to dissolved oxygen in basic solution, followed by production of hydrogen peroxide through dismutation reaction. This method could measure several tea catechins, (+)-catechin (CC), (−)-epigallocatechin-3-gallate (EGCg), (−)-epicatechin-3-gallate (ECG) and gallic acid, with measurement range from 10−7 to 10−3 mol/l and sensitivity of 10−8 mol/l. This method was also applied to the determination of total catechin levels in green tea, black tea and roasted green tea.
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