Author
SAMOYLENKO, VOLODYMYR - University Of Mississippi | |
JACOB, MELISSA - University Of Mississippi | |
KHAN, SHABANA - University Of Mississippi | |
ZHAO, JIANPING - University Of Mississippi | |
TEKWANI, BABU - University Of Mississippi | |
MIDIWO, JACOB - University Of Nairobi | |
WALKER, LARRY - University Of Mississippi | |
MUHAMMAD, ILIAS - University Of Mississippi |
Submitted to: Natural Product Communications
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 3/31/2009 Publication Date: 6/3/2009 Citation: Samoylenko, V., Jacob, M.R., Khan, S.I., Zhao, J., Tekwani, B.L., Midiwo, J.O., Walker, L.A., Muhammad, I. 2009. Antimicrobial, Antiparasitic and Cytotoxic Spermine Alkaloids from Albizia schimperiana. Natural Product Communications. 4(6):791-796. Interpretive Summary: Bioassay guided isolation of the Albizia schimperiana Oliv. (Leguminosae) extract afforded the new macrocyclic spermine alkaloid, 5,14-dimethylbudmunchiamine L1 (1), and three known budmunchiamine analogs (2-4). Compounds 1 and 3 exhibited significant in vitro antimicrobial activity against C. neoformans, methicillin-resistant S. aureus, E. coli, M. intracellulare, and A. fumigatus. In addition, they demonstrated strong in vitro antimalarial activities against CQ-susceptible (D6) and -resistant (W2) strains of Plasmodium falciparum (IC50 = 120-270 ng/mL), and cytotoxicity against human cancer cell lines and mammalian VERO cells. It was observed that hydroxyl substitution of the side chain of the budmunchiamines dramatically reduced the cytotoxicity and antimicrobial activity of the alkaloids (2 and 4) without decreasing antimalarial activity. Technical Abstract: Albizia schimperiana Oliv. (Leguminosae) is a tree distributed in the highland of Kenya, where it is used as a traditional medicine for the treatment of bacterial and parasitic infections, notably pneumonia and malaria, respectively. Bioassay guided isolation of the CH2Cl2–MeOH 1:1/ MeOH-H2O 9:1 (mixed) extract of A. schimperiana afforded the new bioactive macrocyclic spermine alkaloid, namely 5,14-dimethylbudmunchiamine L1 (1), and three known budmunchiamine analogs 2-4. The structures of the compounds 1-4 were determined by 1D and 2D NMR data, including COSY, HMQC, and HMBC experiments, and ESI-HRMS. Compounds 1 and 3 exhibited significant in vitro antimicrobial activity against a panel of microorganisms, including C. neoformans, methicillin-resistant S. aureus, E. coli, M. intracellulare, A. fumigatus. In addition, they demonstrated strong in vitro antimalarial activities against chloroquine-susceptible (D6) and -resistant (W2) strains of Plasmodium falciparum with IC50s ranging from 120-270 ng/mL. Compounds 1-4 were also evaluated for cytotoxic activity against selected human cancer cell lines and mammalian kidney fibroblasts (VERO cells). It was observed that hydroxyl substitution of the side chain of the budmunchiamines dramatically reduced the cytotoxicity and antimicrobial activity of the alkaloids (2 and 4) without decreasing antimalarial activity. |