Interconverting flavanone glucosides and other phenolic compounds in Lippia salviaefolia Cham. ethanol extracts

Author(s):Show less -

Funari, Cristiano Soleo ^[1] ; Passalacqua, Thais Gaban ^[1] ; Rinaldo, Daniel ^[1] ; Napolitano, Assunta ^[2] ; Festa, Michela ^[2] ; Capasso, Anna ^[2] ; Piacente, Sonia ^[2] ; Pizza, Cosimo ^[2] ; Marx Young, Maria Claudia ^[3] ; Durigan, Giselda ^[4] ; Siqueira Silva, Dulce Helena ^[1]

Affiliation

^[1] Sao Paulo State Univ, Inst Chem, BR-14801970 Araraquara, SP - Brazil

^[2] Univ Salerno, Dipartimento Sci Farmaceut, I-84084 Fisciano, SA - Italy

^[3] Inst Bot, Secao Bioquim & Fisiol Plantas, BR-01061970 Sao Paulo - Brazil

^[4] Inst Florestal, BR-19802970 Assis, SP - Brazil

• Document type: Journal article
• Source: Phytochemistry; v. 72, n. 16, p. 2052-2061, NOV 2011.
• Web of Science Citations: 20

Abstract

Four interconverting flavanone glycosides {[}(2R)- and (2S)-3',4',5,6-tetrahydroxyflavanone 7-O-beta-D-glucopyranoside, and (2R)- and (2S)-3',4',5,8-tetrahydroxyflavanone 7-O-beta-D-glucopyranoside], in addition to eight known flavonoids {[}naringenin, asebogenin, sakuranetin, 6-hydroxyluteolin 7-O-beta-D-glucoside, (2R)- and (25)-eriodictyol 7-O-beta-D-glucopyranoside, aromadendrin and phloretin], three phenylpropanoid glycosides {[}forsythoside B. alyssonoside and verbascoside] and the epoxylignan lariciresinol 4'-O-beta-D-glucopyranoside were isolated and identified in the EtOH extract of the aerial parts of Lippia salviaefolia Cham. The phytochemical study herein was guided by preliminary antioxidant tests, namely, beta-carotene protection and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity. The crude extracts, their active fractions and the isolated compounds were assayed against intracellular reactive oxygen species (ROS) and human embryonic kidney HEK-293 and human melanoma M14 cancer cell growth. Aromadendrin and phloretin were able to counteract elevation of ROS induced by the oxidant t-butylhydroperoxide (t-BOOH) in HEK-293 cells, whereas phloretin strongly protected HEK-293 cells from ROS damage at 1 mu M. Additionally, phloretin exhibited a significant growth inhibitory effect at 20-40 mu M in both HEK-293 and M14 cells and induced a concentration dependent apoptosis at 20 mu M in M14 cells, suggesting a selective action towards malignant cells. Due to their equilibria, the four interconverting flavanone glycosides were studied using 10 and 2D NMR, HPLC-CD-PDA and HRMS analyses. (C) 2011 Elsevier Ltd. All rights reserved. (AU)

• FAPESP's process: 04/07932-7 - Search for potential antitumoral, antioxidant, antiinflammatory, antidiabetic, acetylcholinesterase and mieloperoxidase inhibitory natural compounds from Cerrado and Atlantic Forest
• Grantee: Dulce Helena Siqueira Silva
• Support Opportunities: BIOTA-FAPESP Program - Thematic Grants