The EtOH extract of Abrus schimperi (Fabaceae), collected in Kenya, demonstrated significant activity against Leishmania donovani promastigotes with IC50 value of 3.6 μg/mL. Bioassay-guided fractionation of CHCl3 fraction using Centrifugal Preparative TLC afforded two antiparasitic isoflavanquinones, namely amorphaquinone (1) and pendulone (2). They displayed IC50 values of 0.63 μg/mL and 0.43 μg/mL, respectively, against L. donovani promastigotes. Both the compounds were also evaluated against L. donovani axenic amastigotes and amastigotes in THP1 macrophage cultures. In addition, compounds 1 and 2 showed antiplasmodial activity against Plasmodium falciparum D6 and W2 strains, while 2 displayed antibacterial activity against Staphylococcus aureus and methicillin-resistant S. aureus (each IC50 1.44 μg/mL). The 1H and 13C data of 1, not fully assigned previously, were unambiguously assigned using 1D and 2D NMR HMBC and HMQC experiments. In addition, the absolute stereochemistry of the isolated compounds 1 and 2 was revised as C-(3S) based on Circular Dichroism experiments. This appears to be the first report of amorphaquinone (1) and pendulone (2) from the genus Abrus.
DesjeuxP. (2004) Leishmaniasis: current situation and new perspectives. Comparative Immunology, Microbiology & Infectious Diseases, 27, 305–318.
2.
HutchinsonJ, DalzielJM. (1958) Flora of West Tropical Africa.Crown Agents for Overseas Governments and Administration, London, ed. 2, 574–575.
3.
HuJ-M, LavinM, WojciechowskiMF, SandersonMJ. (2000) Phylogenetic systematics of the tribe Millettieae (Leguminosae) based on chloroplast trnK/matK sequences and its implications for evolutionary patterns in Papilionoideae. American Journal of Botany, 87, 418–430.
4.
AnamEM. (2001) Anti-inflammatory activity of compounds isolated from the aerial parts of Abrus precatorius (Fabaceae). Phytomedicine, 8, 24–27.
YadavaRN, ReddyVMS. (2002) A new biologically active flavonol glycoside from the seeds of Abrus precatorius Linn. Journal of Asian natural products research, 4, 103–107.
7.
KareruPG, GachanjaAN, KerikoJM, KenjiGM. (2008) Antimicrobial activity of some medicinal plants used by herbalists in eastern province, Kenya. African Journal of Traditional, Complementary and Alternative medicines, 5, 51–55.
8.
GhoshD, MaitiTK. (2007) Immunomodulatory and antitumor activities of native and heat denatured Abrus agglutinin. Immunobiology, 212, 589-599,
9.
KuoS-C, ChenS-C, ChenL-H, WuJ-B, WangJ-P, TengC-M. (1995). Potent antiplatelet, anti- inflammatory and antiallergic isoflavanquinones from the roots of Abrus precatorius. Planta Medica, 61, 307–312.
10.
Chao-meiMA, NakamuraN, HattoriM. (1998) Saponins and C-glycosyl flavones from the seeds of Abrus precatorius. Chemical and Pharmaceutical Bulletin, 46, 982–987.
11.
OhyamaM, TanakaT, IinumaM. (1998) A prenylated flavanone from roots of Amorpha fruticosa. Phytochemistry, 48, 907–909.
12.
RadwanMM. (2008) Isoflavonoids from an Egyptian collection of Colutea istria. Natural Product Communications, 3, 1491–1494.
13.
HayashiY, ShlratoT, SakuraiK, TakahashiT. (1978) Isoflavanoids from the Heartwood of Millettia pendula BENTH. Mokuzai Gakkaishi, 24, 898-901,
14.
TakahashiM, FuchinoH, SekitaS, SatakeM, KiuchiF. (2006) In Vitro leishmanicidal constituents of Millettia pendula. Chemical and Pharmaceutical Bulletin, 54, 915–917.
15.
KurosawaK, OllisWD, RedmanBT, SutherlandIO. (1968) The absolute configuration of the animal metabolite, equol, three naturally occurring isovlavans, and one natural isovlavanquinone. Chemical Communications, 1265–1267.
GottliebOR, de OliveiraAB, GoncalvesTMM, de OliveiraGG, PereiraSA. (1975) Isoflavonoids from Cyclolobium species. Phytochemistry, 14, 2495–2499.
22.
MoffittW and MoscowitzA. (1959) Optical Activity in Absorbing Media. The Journal of Chemical Physics, 30, 648–660.
23.
CrabbeP. (1967) Recent applications of optical rotatory dispersion and optical circular dichroism in organic chemistry. In: AllingerNL, ElielEL. (Eds.), Topics in Stereochemistry, vol. 1. Wiley, New York, London and Sydney, pp. 93–185.
24.
MockRS and GrimsrudEP. (1990) Optically enhanced electron capture by p-benzoquinone and its methylated derivatives. The Journal of Physical Chemistry, 94, 3550–3553.
25.
SladeD, FerreiraD, MaraisJPJ. (2005) Circular dichroism, a powerful tool for the assessment of absolute configuration of flavonoids. Phytochemistry, 66, 2177–2215.
26.
KurosawaK, OllisWD, SutherlandIO, GottliebOR, de OliveiraAB. (1978) Mucronulatol, mucroquinone and mucronucarpan, isovlavonoids from Machaerium mucronulatum and M. villosum. Phytochemistry, 17, 1405–1411.
27.
RahmanAA, SamoylenkoV, JacobMR, SahuR, JainSK, KhanSI, TekwaniBL, MuhammadI. (2011) Antiparasitic and Antimicrobial Indolizidines from the Leaves of Prosopis glandulosa var. glandulosa. Planta Medica, 77, 1639–1643.
28.
MikusJ, SteverdingD. (2000) A simple colorimetric method to screen drug cytotoxicity against Leishmania using the dye Alamar Blue. Parasitology International, 48, 265–269.
29.
SamoylenkoVP, AshfaqMK, JacobMR, TekwaniBL, KhanSI, ManlySP, JoshiVC, WalkerLA, IliasM. (2009) Indolizidine, antiinfective and antiparasitic compounds from Prosopis glandulosa var. glandulosa. Journal of Natural Products, 72, 92–98.
30.
MaklerMT, RiesJM, WilliamsJA, BancroftJE, PiperRC, GibbinsBL, HinrichsDJ. (1993) Parasite Lactate Dehydrogenase as an assay for Plasmodium falciparum drug sensitivity. American Journal of Tropical Medicine and Hygiene, 48, 739–741.
31.
NCCLS. (2002) Reference method for broth dilution antifungal susceptibility testing of yeasts. Approved standard, 2nd ed. National Committee for Clinical Laboratory Standards, 22, 1–51.
32.
NCCLS. (2000) Methods for dilution antimicrobial susceptibility tests for bacteria that grow aerobically. NCCLS Document M7-A5. National Committee for Clinical Laboratory Standards, 20, 1–58.
BorenfreundE, BabichH, Martin-AlguacilN. (1990) Rapid chemosensitivity assay with human normal and tumor cells in vitro. In vitro cellular & developmental biology: Journal of the Tissue Culture Association, 26, 1030–1034.
