Marianna V S Castello Branco

Publications (3)4.38 Total impact

• Article: Tropane Alkaloids from Erythroxylum caatingaePlowman

  Steno L. de Oliveira, Josean F. Tavares, Marianna V. S. Castello Branco, Hellane F. S. Lucena, José M. Barbosa-Filho, Maria de F. Agra, Silene C. do Nascimento, Jaciana dos S. Aguiar, Teresinha G. da Silva, Carlos A. de Simone, João X. de Araújo-Júnior, Marcelo S. da Silva
  Chemistry & Biodiversity 01/2011; 8(1):155 - 165. · 1.80 Impact Factor
• Article: Tropane alkaloids from Erythroxylum caatingae Plowman.

  Steno L de Oliveira, Josean F Tavares, Marianna V S Castello Branco, Hellane F S Lucena, José M Barbosa-Filho, Maria de F Agra, Silene C do Nascimento, Jaciana dos S Aguiar, Teresinha G da Silva, Carlos A de Simone, João X de Araújo-Júnior, Marcelo S da Silva
  [show abstract] [hide abstract]
  ABSTRACT: Three tropane alkaloids, 1-3, were isolated from Erythroxylum caatingae, i.e., 6β-benzoyloxy-3α-[(4-hydroxy-3,5-dimethoxybenzoyl)oxy]tropane (1), a new tropane alkaloid, along with the known alkaloids 3α,6β-dibenzoyloxytropane (2) and 6β-benzoyloxy-3α-[(3,4,5-trimethoxybenzoyl)oxy]tropane (catuabine B; 3). Their structures were determined by 2D- ((1) H and (13) C) NMR. By LC/ESI-MS/MS analysis of the fractions of alkaloids 1-3, it was possible to detect five more alkaloids, 4-8, two of these, 4 and 8, possibly being new natural products. X-Ray crystallography of the chloride derivate of 1, i.e., 6β-benzoyloxy-3α-(4-hydroxy-3,5-dimethoxybenzoyloxy)tropane hydrochloride (1a) confirmed the structure of 1. Cytotoxicity was tested against the cell lines HEp-2, NCI-H292, and KB for the MeOH extract and alkaloid 3, and antitumor activity was tested against Sarcoma 180 only for the MeOH extract.
  Chemistry & Biodiversity 01/2011; 8(1):155-65. · 1.80 Impact Factor
• Article: Diterpenes from Xylopia langsdorffiana inhibit cell growth and induce differentiation in human leukemia cells.

  Marianna V S Castello Branco, Maristella C Anazetti, Marcelo S Silva, Josean F Tavares, Margareth F F Melo Diniz, Lucas Frungillo, Marcela Haun, Patrícia S Melo
  [show abstract] [hide abstract]
  ABSTRACT: Two new diterpenes were isolated from stems and leaves of Xylopia langsdorffiana, ent-atisane-7alpha,16alpha-diol (xylodiol) and ent-7alpha-acetoxytrachyloban-18-oic acid (trachylobane), along with the known 8(17),12E,14-labdatrien-18-oic acid (labdane). We investigated their antitumour effects on HL60, U937 and K562 human leukemia cell lines. We found that xylodiol was the most potent diterpene in inhibiting cell proliferation of HL60, U937 and K562 cells, with mean IC50 values of 90, 80 and 50 microM, respectively. Based on the nitroblue tetrazolium (NBT) reduction assay, all the diterpenes were found to induce terminal differentiation in HL60 and K562 cells, with xylodiol being the most effective. NBT reduction was increased by almost 120% after 12 h exposure of HL60 cells to xylodiol at a concentration lower than the IC50 (50 microM). Thus, xylodiol inhibited human leukemia cell growth in vitro partly by inducing cell differentiation, and merits further studies to examine its mechanism of action as a potential antitumoural agent.
  Zeitschrift fur Naturforschung C 64(9-10):650-6. · 0.77 Impact Factor