title: Free radical scavenging property and antiproliferative activity of Rhodiola imbricata Edgew extracts in HT-29 human colon cancer cells.
abstract: OBJECTIVE
  To investigate the in vitro antioxidant and antiproliferative activity of rhizome extracts of Rhodiola imbricata (R. imbricata) in HT-29 human colon cancer cell line.
  
  
  METHODS
  The successively extracted rhizome of R. imbricata using various solvents was analyzed for their total phenolics, tannins and flavonoid contents. In vitro antioxidant activity was evaluated by employing different assays, including DPPH, ABTS radical scavenging assays, FRAP, phosphomolybdenum reduction assay, superoxide anion, hydroxyl radical scavenging activities and metal chelating ability.
  
  
  RESULTS
  Acetone and methanol extracts recorded higher phenolic content and showed comparable antioxidant activity with standard reference. Additionally, they also inhibited the proliferation of HT-29 cells upon treatment at higher concentration (200 μg/mL) (acetone and methanol, 84% and 84%, respectively). On examination acetone extract exhibited antiproliferative activity in a concentration dependent manner whereas, methanol extract showed both dose dependent and time dependent inhibitory activity.
  
  
  CONCLUSIONS
  The results obtained justify the traditional usage of R. imbricata from their promising antioxidant activity.
authors: Bioprospecting Laboratory, Department of Botany, School of Life Sciences, Bharathiar University, Coimbatore - 641 046, Tamil Nadu, India.
authors: Ravichandran
authors: R
authors: Senthilkumar
authors: Thangaraj
authors: T
authors: Parimelazhagan
authors: Om Prakash
authors: OP
authors: Chaurasia
authors: R B
authors: RB
authors: Srivastava
mesh_terms: D000704:Analysis of Variance; D049109:Cell Proliferation / Q000187:drug effects; D003110:Colonic Neoplasms / Q000188:drug therapy* / Q000473:pathology; D016166:Free Radical Scavengers / Q000737:chemistry / Q000494:pharmacology*; D019073:HT29 Cells; D006801:Humans; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry; D029771:Rhodiola / Q000737:chemistry*
chemical_list: D016166:Free Radical Scavengers; D010936:Plant Extracts