Susana C. Núñez Montoya

CHEMOTAXONOMIC FEATURES IN ARGENTINIAN SPECIES OF FLAVERIA (COMPOSITAE)

Abstract The presence of thiophene derivatives in Flaveria bidentis and Flaveria bidentis var. angustifolia has been investigated to expand on the existing chemical information on both taxa. Alpha-terthienyl and 5- (3-buten-1-ynyl)- 2,2′-bithienyl were found in the roots and aerial parts of F. bidentis, whereas in F. bidentis var. angustifolia α-terthienyl was found only in the roots. These results, in conjunction with the different patterns of sulphated flavonoids present in each one of these entities, reinforce the differentiation, based on exomorphological features, of Argentinian Flaveria into two species: F. bidentis and F. haumanii (formerly F. bidentis var. angustifolia).

Apoptosis and mutagenicity induction by a characterized aqueous extract of Baccharis articulata (Lam.) Pers. (Asteraceae) on normal cells

In a previous study we have demonstrated that cold aqueous extract of Baccharis articulata (Ba-CAE) induced the death of human peripheral blood mononuclear cells (PBMCs) and exerted low mutagenic effects on mice at 6h after administration. The aim of this work was to investigate whether the PBMCs death induced by Ba-CAE is due to apoptosis, and whether this extract exerts mutagenic effects on mice at 24 and 48h after administration. In addition, Ba-CAE was chemically characterized. PBMCs from healthy volunteers were exposed to extract (10, 20, 40, 80, 160, 320, 640 and 1280μg/mL) for 18-24h. Cell viability was determined by staining of trypan blue dye exclusion method. Apoptosis was determined by Hoechst 33258 staining, TUNEL, and DNA fragmentation analysis by agarose gel electrophoresis. BALB/c mice were injected with extract (1800, 900 and 450mg/kg) and sacrificed at 24 and 48h postinjection. Bone marrow samples were used to assess chromosome mutations by the micronucleus test. The extract induced PBMCs death by apoptosis and increased the frequency of micronuclei in bone marrow. The phytochemical study of Ba-CAE showed the presence of flavones as luteolin and acacetin, caffeoylquinic acids as chlorogenic acid, and tannins.