Development and Validation of an On-Line HPLC-DAD-Antioxidant Assay (ORAC)/ESI-HRMS System to Identify Antioxidant Compounds in Complex Mixtures.

An online high-performance liquid-chromatography-diode-array detector coupled with detection of antioxidant compounds using oxygen radical absorbance capacity (ORAC) assay and electrospray ionization-high-resolution mass spectrometer (HPLC-DAD-antioxidant assay (ORAC)/ESI-HRMS) was developed for the identification of antioxidant compounds in complex mixtures. The method was validated using quercetin and a mixture of antioxidant compounds with different antioxidant activities (resveratrol, dihydroxymethoxy-dihydrochalcone, ferulic acid, baicalein and luteolin). Accuracy of the system was established by comparing the results from the developed system with those from ORAC microplate assay determination and reveals the ability of the system to determine the respective contribution of antioxidant compounds to the whole activity of complex mixtures.

Comprehensive characterization of naturally occurring antioxidants from the twigs of mulberry (Morus alba) using on-line high-performance liquid chromatography coupled with chemical detection and high-resolution mass spectrometry.

Introduction: The mulberry tree (Morus alba L.) is a prolific source of biologically active compounds. There is considerable growing interest in probing M.

Purification of vetiver alcohols and esters for quantitative high-performance thin-layer chromatography determination in Haitian vetiver essential oils and vetiver acetates.

A simple, fast, and efficient High-Performance Thin-Layer Chromatography (HPTLC) method was developed for the simultaneous quantitative determination of alcohols and acetates in Haitian vetiver essential oils (Chryzopogon zizanioides) and its acetylated form. Analytes were separated by using a mixture of n-hexane-chloroform-ethyl acetate (8:6:0.5, v/v/v) as mobile phase under 47% humidity.