HPLC-DPPH Screening Method for Evaluation of Antioxidant Compounds Extracted from Semen Oroxyli

Semen Oroxyli, derived from the seed of Oroxylum indicum L., is a commonly used Traditional Chinese Medicine with beneficial effects against several respiratory disorders. Antioxidative flavonoids may be partly responsible for its medicinal functions. The aim of this study was to rapidly determine the antioxidants in Semen Oroxyli based on a HPLC-DPPH method. Four major flavonoids, baicalein-7-O-gentiobioside, baicalein-7-O-glucoside, baicalein, and baicalin, were identified as the active components against DPPH free radicals, which is in accord with the results of our former traditional activity-guided phytochemical study. The oxidative products of the four antioxidant flavonoids were studied in the DPPH spiking HPLC assay, it was suggested that the three active flavonoid glycosides were converted into 5,6-dihydroxy-7-methoxyflavone, which implied that an additional hydroxyl at C-6 in 5,7-dihydroxyflavones plays an important role in the DPPH assay.

[1]  N. Trinajstic,et al.  SAR and QSAR of the antioxidant activity of flavonoids. , 2007, Current medicinal chemistry.

[2]  I. Rahman,et al.  Oxidative stress in asthma and COPD: antioxidants as a therapeutic strategy. , 2006, Pharmacology & therapeutics.

[3]  Identification and quantification of free radical scavengers in the flower buds of Lonicera species by online HPLC-DPPH assay coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry. , 2012, Biomedical chromatography : BMC.

[4]  T. V. van Beek,et al.  Evaluation and comparison of two improved techniques for the on-line detection of antioxidants in liquid chromatography eluates. , 2001, Journal of chromatography. A.

[5]  Mijun Peng,et al.  Comparative evaluation of three methods based on high-performance liquid chromatography analysis combined with a 2,2′-diphenyl-1-picrylhydrazyl assay for the rapid screening of antioxidants from Pueraria lobata flowers , 2012, Analytical and Bioanalytical Chemistry.

[6]  Irfan Rahman,et al.  Regulation of inflammation and redox signaling by dietary polyphenols. , 2006, Biochemical pharmacology.

[7]  A. Tiwari,et al.  Gastroprotective flavonoid constituents from Oroxylum indicum Vent. , 2010, Bioorganic & medicinal chemistry letters.

[8]  Li-juan Chen,et al.  Isolation and identification of four flavonoid constituents from the seeds of Oroxylum indicum by high-speed counter-current chromatography. , 2003, Journal of chromatography. A.

[9]  T. V. van Beek,et al.  An on-line HPLC method for detection of radical scavenging compounds in complex mixtures. , 2000, Analytical chemistry.

[10]  T. Namba,et al.  Studies on the Nepalese Crude Drugs (VIII) : On the Flavonoid Constituents of the Seed of Oroxylum indicum VENT. , 1988 .

[11]  Ren-yi Yan,et al.  Antioxidant flavonoids from the seed of Oroxylum indicum. , 2011, Fitoterapia.

[12]  A. Nair,et al.  Flavonoids of the leaves of Oroxylum indicum and Pajanelia longifolia , 1972 .

[13]  Hongliang Liu,et al.  Quality evaluation of semen oroxyli based on the determination of multiple components with a single reference standard. , 2013, Journal of chromatographic science.

[14]  T. Rades,et al.  Application of an online post‐column derivatization HPLC‐DPPH assay to detect compounds responsible for antioxidant activity in Sonchus oleraceus L. leaf extracts , 2013, The Journal of pharmacy and pharmacology.

[15]  Paul S. Francis,et al.  High-performance liquid chromatography with post-column 2,2'-diphenyl-1-picrylhydrazyl radical scavenging assay: methodological considerations and application to complex samples. , 2010, Analytica chimica acta.