Improving the in vivo predictability of an on-line HPLC stable free radical decoloration assay for antioxidant activity in methanol–buffer medium

Identification of phenolic compounds from pomegranate (Punica granatum L.) seed residues and investigation into their antioxidant capacities by HPLC–ABTS+ assay

“…HPLC-ABTS + assay is more sensitive than the HPLC-DPPH for an estimation of the water-soluble antioxidants (Pellegrini et al, 2003). Furthermore, the reaction between DPPH·and an antioxidant exhibited slow kinetics in methanolic medium (Bartasiute, Westerink, Verpoorte, & Niederländer Harm, 2007). Accordingly, on line HPLC-ABTS + rapid screening of individual antioxidants in PSR extract and fractions was established.…”

Chromatography in Bioactivity Analysis of Compounds

“…A reaction coil, which is a capillary tube with a length ranging from 0.2 to 15 m, is where a reaction takes place between the mixture components and the DPPH reagent. Bartasiute and co-workers [66] analysed the method with capillaries of different lengths. The shortest capillary used in their experiment (0.2 m) ensured sufficient reaction time.…”

“…However, specific properties of analysed mixtures should be taken into account, whose components may react differently. The last element is another detector which records the characteristic signal of the DPPH • solution [65,66,67,68]. Fading of a radical signal after reaction with an antioxidant (visible as a negative peak) is proportional to its oxidative force.…”

Screening and Identification of Antioxidant Components in the Extract of Puerariae radix Using HPLC Coupled with MS

“…The DPPH· radical scavenging assay was performed as the reference (Bartasiute et al 2007) with minor modification. A series of the concentrations of puerarin, daidzin, and daidzein were prepared with methanol and then 2.0 mL of the sample solution mixed with 2.0 mL of 0.2 mM DPPH· radical solution.…”