Molecular and Cellular Biochemistry

, Volume 273, Issue 1, pp 193–208

Antioxidant activity of fractionated extracts of rhizomes of high-altitude Podophyllum hexandrum: Role in radiation protection

  • Raman Chawla
  • Rajesh Arora
  • Raj Kumar
  • Ashok Sharma
  • Jagdish Prasad
  • Surendar Singh
  • Ravinder Sagar
  • Pankaj Chaudhary
  • Sandeep Shukla
  • Gurpreet Kaur
  • Rakesh Kumar Sharma
  • Satish Chander Puri
  • Kanaya Lal Dhar
  • Geeta Handa
  • Vinay Kumar Gupta
  • Ghulam Nabi Qazi
Article

DOI: 10.1007/s11010-005-0821-5

Cite this article as:
Chawla, R., Arora, R., Kumar, R. et al. Mol Cell Biochem (2005) 273: 193. doi:10.1007/s11010-005-0821-5

Abstract

Whole extract of rhizomes of Podophyllum hexandrum has been reported earlier by our group to render whole-body radioprotection. High-altitude P. hexandrum (HAPH) was therefore fractionated using solvents of varying polarity (non-polar to polar) and the different fractions were designated as, n-hexane (HE), chloroform (CE), alcohol (AE), hydro-alcohol (HA) and water (WE). The total polyphenolic content (mg% of quercetin) was determined spectrophotometrically, while. The major constituents present in each fraction were identified and characterized using LC-APCI/MS/MS. In vitro screening of the individual fractions, rich in polyphenols and lignans, revealed several bioactivities of direct relevance to radioprotection e.g. metal-chelation activity, antioxidant activity, DNA protection, inhibition of radiation (250 Gy) and iron/ascorbate-induced lipid peroxidation (LPO). CE exhibited maximum protection to plasmid (pBR322) DNA in the plasmid relaxation assay (68.09% of SC form retention). It also showed maximal metal chelation activity (41.59%), evaluated using 2,2′-bipyridyl assay, followed by AE (31.25%), which exhibited maximum antioxidant potential (lowest absorption unit value: 0.0389± 0.00717) in the reducing power assay. AE also maximally inhibited iron/ascorbate-induced and radiation-induced LPO (99.76 and 92.249%, respectively, at 2000 μg/ml) in mouse liver homogenate. Under conditions of combined stress (radiation (250 Gy) + iron/ascorbate), at a concentration of 2000 μg/ml, HA exhibited higher percentage of inhibition (93.05%) of LPO activity. HA was found to be effective in significantly (p < 0.05) lowering LPO activity over a wide range of concentrations as compared to AE. The present comparative study indicated that alcoholic (AE) and hydro-alcoholic (HA) fractions are the most promising fractions, which can effectively tackle radiation-induced oxidative stress.

Keywords

2,2′-bipyridylfree radicallipid peroxidationpolyphenolsradioprotectionoxidative stressPodophyllum hexandrum

Copyright information

© Springer Science + Business Media, Inc. 2005

Authors and Affiliations

  • Raman Chawla
    • 1
  • Rajesh Arora
    • 1
  • Raj Kumar
    • 1
  • Ashok Sharma
    • 1
  • Jagdish Prasad
    • 1
  • Surendar Singh
    • 1
  • Ravinder Sagar
    • 1
  • Pankaj Chaudhary
    • 1
  • Sandeep Shukla
    • 1
  • Gurpreet Kaur
    • 1
  • Rakesh Kumar Sharma
    • 1
    • 3
  • Satish Chander Puri
    • 2
  • Kanaya Lal Dhar
    • 2
  • Geeta Handa
    • 2
  • Vinay Kumar Gupta
    • 2
  • Ghulam Nabi Qazi
    • 2
  1. 1.Division of Radiopharmaceuticals and Radiation BiologyInstitute of Nuclear Medicine and Allied SciencesNew DelhiIndia
  2. 2.Natural Products Chemistry DivisionRegional Research Laboratory (CSIR)JammuIndia
  3. 3.Division of Radiopharmaceuticals and Radiation BiologyInstitute of Nuclear Medicine and Allied SciencesNew DelhiIndia