title: Isolation and identification of cytotoxic compounds from the rhizomes of Paris quadrifolia L.
abstract: BACKGROUND
  Paris quadrifolia L. is a medicinal plant which contains steroidal saponins. The present study reports isolation and structural identification of six pennogenyl saponins obtained from P. quadrifolia rhizomes. The four spirostan saponins were obtained from P. quadrifolia for the first time. The cytotoxic effects of the sub-fractions and six compounds isolated from the plant extract were evaluated on tumour cells.
  
  
  METHODS
  Ethanol extract from the rhizomes of P. quadrifolia were partinioned using column chromatography. The saponins were isolated from the obtained sub-fractions by isocratic RP HPLC and their structures were determined by means of 1D and 2D NMR spectroscopy and MALDI TOF MS. The cytotoxic effects of the sub-fractions and the isolated compounds were tested against human promyelocytic leukaemia cells (HL-60), human cervical adenocarcinoma cells (HeLa) and human breast cancer cells (MCF-7) using the [(3-(4,5-dimethylthiazol-2-yl)]-2,5-diphenyltetrazolium bromide (MTT) assay.
  
  
  RESULTS
  Six pennogenyl saponins were isolated from P. quadrifolia rhizomes: pennogenin 3-O-β-D-glucopyranoside (1), pennogenin 3-O-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranoside (2), pennogenin 3-O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranoside (3), pennogenin 3-O-α-L-rhamnopyranosyl-(1→4)-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranoside (4), pennogenin 3-O-α-L-rhamnopyranosyl-(1→4)-[α-L-rhamnopyranosyl-(1→2)]-β-D-glucopyranoside (5), pennogenin 3-O-α-L-rhamnopyranosyl-(1→4)-α-L-rhamnopyranosyl-(1→4)-[α-L-rhamnopyranosyl-(1→2)]-β-D-glucopyranoside (6). Pennogenyl saponins 5 and 6 exhibited cytotoxic activity against HL-60, HeLa and MCF-7 tumour cells with IC50 values of 1.0 ± 0.04 μg/ml, 1.8 ± 0.072 μg/ml and 2.4 ± 0.096 μg/ml respectively, and 2.0 ± 0.08 μg/ml, 2.5 ± 0.125 μg/ml and 3.2 ± 0.128 μg/ml respectively.
  
  
  CONCLUSIONS
  Compounds 1-4 were isolated from this species for the first time.
authors.affiliation: Department of Chemistry, University of Gdańsk, Wita Stwosza 63, 80-308, Gdańsk, Poland.
authors.forename: Jerzy
authors.initials: J
authors.lastname: Gajdus
authors.affiliation: Department of Chemistry, University of Gdańsk, Wita Stwosza 63, 80-308, Gdańsk, Poland.
authors.forename: Zbigniew
authors.initials: Z
authors.lastname: Kaczyński
authors.affiliation: Department of Biotechnology, Intercollegiate Faculty of Biotechnology, University of Gdańsk and Medical University of Gdańsk, Kładki 24, 80-822, Gdańsk, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Kawiak
authors.affiliation: Department of Biotechnology, Intercollegiate Faculty of Biotechnology, University of Gdańsk and Medical University of Gdańsk, Kładki 24, 80-822, Gdańsk, Poland.
authors.forename: Ewa
authors.initials: E
authors.lastname: Lojkowska
authors.affiliation: Department of Biology and Pharmaceutical Botany, Medical University of Gdańsk, Hallera 107, 80-416, Gdańsk, Poland.
authors.forename: Justyna
authors.initials: J
authors.lastname: Stefanowicz-Hajduk
authors.affiliation: Department of Biology and Pharmaceutical Botany, Medical University of Gdańsk, Hallera 107, 80-416, Gdańsk, Poland.
authors.forename: J Renata
authors.initials: JR
authors.lastname: Ochocka
authors.affiliation: Department of Chemistry, University of Gdańsk, Wita Stwosza 63, 80-308, Gdańsk, Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Stepnowski
keywords: Cytotoxicity; Paris quadrifolia; pennogenin; saponins; structure elucidation