TY  - JOUR
A1  - Muthaura, Charles N.
A1  - Keriko, Joseph M.
A1  - Mutai, Charles
A1  - Yenesew, Abiy
A1  - Heydenreich, Matthias
A1  - Atilaw, Yoseph
A1  - Gathirwa, Jeremiah W.
A1  - Irungu, Beatrice N.
A1  - Derese, Solomon
T1  - Antiplasmodial, cytotoxicity and phytochemical constituents of four maytenus species used in traditional medicine in Kenya
JF  - The natural products journal
N2  - Background: In Kenya, several species of the genus Maytenus are used in traditional medicine to treat many diseases including malaria. In this study, phytochemical constituents and extracts of Maytenus undata, M. putterlickioides, M. senegalensis and M. heterophylla were evaluated to determine compound/s responsible for antimalarial activity. 
Objective: To isolate antiplasmodial compounds from these plant species which could be used as marker compounds in the standardization of their extracts as a phytomedicine for malaria. 
Methods: Constituents were isolated through activity-guided fractionation of the MeOH/CHCl3 (1:1) extracts and in vitro inhibition of Plasmodium falciparum. Cytotoxicity was evaluated using Vero cells and the compounds were elucidated on the basis of NMR spectroscopy.
Results: Fractionation of the extracts resulted in the isolation of ten known compounds. Compound 1 showed promising antiplasmodial activity with IC50, 3.63 and 3.95 ng/ml against chloroquine sensitive (D6) and resistant (W2) P. falciparum, respectively and moderate cytotoxicity (CC50, 37.5 ng/ml) against Vero E6 cells. The other compounds showed weak antiplasmodial (IC50 > 1.93 mu g/ml) and cytotoxic (CC50 > 39.52 mu g/ml) activities against P. falciparum and Vero E6 cells, respectively. 
Conclusion: (20 alpha)-3-hydroxy-2-oxo-24-nor-friedela-1(10),3,5,7-tetraen-carboxylic acid-(29)-methyl-ester (pristimerin) (1) was the most active marker and lead compound that warrants further investigation as a template for the development of new antimalarial drugs. Pristimerin is reported for the first time in M. putterlickioides. 3-Hydroxyolean-12-en-28-oic acid (oleanolic acid) (5), stigmast-5-en-3-ol (beta-sitosterol) (6), 3-oxo-28-friedelanoic acid (7), olean-12-en-3-ol (beta-amyrin) (8), lup-20(29)-en-3-ol (lupeol) (9) and lup-20(29)-en-3-one (lupenone) (10) are reported for the first time in M. undata.
KW  - Antimalarial plants
KW  - antiplasmodial
KW  - cytotoxicity
KW  - marker compound
KW  - Maytenus spp.
KW  - phytomedicine
KW  - pristimerin
Y1  - 2017
U6  - https://doi.org/10.2174/2210315507666161206144050
SN  - 2210-3155
SN  - 2210-3163
VL  - 7
IS  - 2
SP  - 144
EP  - 152
PB  - Bentham Science Publ.
CY  - Sharjah
ER  - 
TY  - JOUR
A1  - Deyou, Tsegaye
A1  - Marco, Makungu
A1  - Heydenreich, Matthias
A1  - Pan, Fangfang
A1  - Gruhonjic, Amra
A1  - Fitzpatrick, Paul A.
A1  - Koch, Andreas
A1  - Derese, Solomon
A1  - Pelletier, Jerry
A1  - Rissanen, Kari
A1  - Yenesew, Abiy
A1  - Erdelyi, Mate
T1  - Isoflavones and Rotenoids from the Leaves of Millettia oblata ssp teitensis
JF  - Journal of natural products
N2  - A new isoflavone, 8-prenylmilldrone (1), and four new rotenoids, oblarotenoids A-D (2-5), along with nine known compounds (6-14), were isolated from the CH2Cl2/CH3OH (1:1) extract of the leaves of Millettia oblata ssp. teitensis by chromatographic separation. The purified compounds were identified by NMR spectroscopic and mass spectrometric analyses, whereas the absolute configurations of the rotenoids were established on the basis of chiroptical data and in some cases by single-crystal X-ray crystallography. Maximaisoflavone J (11) and oblarotenoid C (4) showed weak activity against the human breast cancer cell line MDA-MB-231 with IC50 values of 33.3 and 93.8 mu M, respectively.
Y1  - 2017
U6  - https://doi.org/10.1021/acs.jnatprod.7b00255
SN  - 0163-3864
SN  - 1520-6025
VL  - 80
SP  - 2060
EP  - 2066
PB  - American Chemical Society
CY  - Washington
ER  - 
TY  - JOUR
A1  - Marco, Makungu
A1  - Deyou, Tsegaye
A1  - Gruhonjic, Amra
A1  - Holleran, John
A1  - Duffy, Sandra
A1  - Heydenreich, Matthias
A1  - Firtzpatrick, Paul A.
A1  - Landberg, Goran
A1  - Koch, Andreas
A1  - Derese, Solomon
A1  - Pelletier, Jerry
A1  - Avery, Vicky M.
A1  - Erdelyi, Mate
A1  - Yenesew, Abiy
T1  - Pterocarpans and isoflavones from the root bark of Millettia micans and of Millettia dura
JF  - Phytochemistry letters
KW  - Millettia micans
KW  - Millettia dura
KW  - Pterocarpan
KW  - Isoflavone
KW  - Cytotoxicity
KW  - Plasmodium falciparum
Y1  - 2017
U6  - https://doi.org/10.1016/j.phytol.2017.07.012
SN  - 1874-3900
SN  - 1876-7486
VL  - 21
SP  - 216
EP  - 220
PB  - Elsevier
CY  - Amsterdam
ER  -