Quinolizidine Alkaloid Profiles of Lupinus Varius Orientalis, L
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Quinolizidine Alkaloid Profiles of Lupinus varius orientalis , L. albus albus, L. hartwegii, and L. densiflorus Assem El-Shazlya, Abdel-Monem M. Ateya 3 and Michael W inkb * a Department of Pharmacognosy, Faculty of Pharmacy, Zagazig University, Zagazig, Egypt b Institut für Pharmazeutische Biologie der Universität, Im Neuenheimer Feld 364, 69120 Heidelberg, Germany. Email: [email protected] * Author for correspondence and reprint requests Z. Naturforsch. 56c, 21-30 (2001); received September 20/0ctober 25, 2000 Quinolizidine Alkaloids, Biological Activity Alkaloid profiles of two Lupinus species growing naturally in Egypt (L. albus albus [syn onym L. termis], L. varius orientalis ) in addition to two New World species (L. hartwegii, L. densiflorus) which were cultivated in Egypt were studied by capillary GLC and GLC-mass spectrometry with respect to quinolizidine alkaloids. Altogether 44 quinolizidine, bipiperidyl and proto-indole alkaloids were identified; 29 in L. albus, 13 in L. varius orientalis, 15 in L. hartwegii, 6 in L. densiflorus. Some of these alkaloids were identified for the first time in these plants. The alkaloidal patterns of various plant organs (leaves, flowers, stems, roots, pods and seeds) are documented. Screening for antimicrobial activity of these plant extracts demonstrated substantial activity against Candida albicans, Aspergillus flavus and Bacillus subtilis. Introduction muscarinic acetylcholine receptors (Schmeller et al., 1994) as well as Na+ and K+ channels (Körper Lupins represent a monophyletic subtribe of the et al., 1998). In addition, protein biosynthesis and Genisteae (Leguminosae) (Käss and Wink, 1996, membrane permeability are modulated at higher 1997a, b). Whereas more than 300 species have doses (Wink and Twardowski, 1992). been reported from the New World (North and In the course of our study on the Egyptian le South America) only 12 species are known from gumes containing quinolizidine alkaloids (El- Europe (Mediterranean region) and North Africa. Shazly et al., 1996a, b) we have investigated the A characteristic trait of all lupins is the pro active constituents and antimicrobial activity of duction of quinolizidine and bipiperidine alkaloids four Lupinus species growing and/or being culti (reviews, Kinghorn and Balandrin, 1984; Wink, vated in Egypt. These species have been analysed 1993) which constitute essential defence com before in our laboratory, but material had mainly pounds against herbivores, but are also acting derived from plants grown in the greenhouse, in against microorganisms and competing plants (re the experimental garden in Germany or from views in Wink, 1984, 1987, 1988, 1992, 1993). Most seeds (Wink et al., 1995; Wink and W itte, 1991, lupin alkaloids are toxic to animals (symptoms are 1993). About 8 alkaloids were identified already cramps, vomiting and even death due to respira in the seeds of L. varius, 31 in L. albus, 13 in L. tory paralysis). The pharmacological responses in hartwegii (Wink et al., 1995). Recently, 14 alkaloids clude oxytocic, uteretonic, hypoglycemic, hypoten were isolated from the seeds of L. varius and 13 sive and antiarrhythmic activities (Kinghorn and from L. hartwegii growing in Egypt (Mohamed Balandrin, 1984). Lupins which accumulate ana- and Hassanean, 1997). Egyptian termis (L. albus ) gyrine and the bipiperidine alkaloid ammoden- has been subjected to intensive investigation and drine exhibit mutagenic properties and produce 15 alkaloids have been isolated and identified by crooked calf disease in grazing animal especially GLC-MS (Mohamed et al., 1990; 1991; 1992; 1994; when consumed in early foetal stages (Keeler, Mohamed and Shorbagi, 1993). 1969, 1976; K eeler et a l, 1977). Capillary gas-liquid chromatography (GLC) in The main molecular targets which are affected combination with mass spectrometry (GLC-MS) is by quinolizidine alkaloids (QAs) are nicotinic and a rapid and powerful technique for the analysis of 0939-5075/2001/0100-0021 $ 06.00 © 2001 Verlag der Zeitschrift für Naturforschung, Tübingen • www.znaturforsch.com • D Dieses Werk wurde im Jahr 2013 vom Verlag Zeitschrift für Naturforschung This work has been digitalized and published in 2013 by Verlag Zeitschrift in Zusammenarbeit mit der Max-Planck-Gesellschaft zur Förderung der für Naturforschung in cooperation with the Max Planck Society for the Wissenschaften e.V. digitalisiert und unter folgender Lizenz veröffentlicht: Advancement of Science under a Creative Commons Attribution Creative Commons Namensnennung 4.0 Lizenz. 4.0 International License. 22 A. El-Shazly and M. Wink • Quinolizidine Alkaloids complex QA mixtures (Wink et al., 1991; Wink, tive alkaloid profiles. The alkaloid extracts were 1993; Wink et al., 1993, 1995). Since a large library subjected to GLC-mass spectrometry. of mass spectral and GLC retention index (RI) data of authentic QAs is available in our labora Capillary GLC tory, we were able to unambiguously identify most QAs in this study and have found a number of Separation of quinolizidine alkaloid mixtures alkaloids which were new for the species studied. ' was carried out with a Carlo Erba ICU 600 gas chromatograph equipped with FID and spectra physics integrator. Column: DB1-30 W (15 m, Materials and Methods 0.317 mm ID). Conditions: carrier gas He (2 ml / min.); detector temp. 300° C; injector temp. Plant material 250° C; oven temp, program: initial 150° C 2 min. Plants of L. albus L. ssp. albus (L. termis isothermal, 150-250° C at 15 min-1, 250-300° C Forssk.) were collected from the fields near Za- at 25 min“-1, 300° C, 5 min isothermal. Retention gazig during the flowering season or when mature indices (RI): Kovats indices (Kovats, 1958) were fruits were formed in March to May 1997. Seeds calculated with respect to a set of co-injected even of L. varius ssp. orientalis and L. densiflorus, were numbered hydrocarbons (Ci 0 - C 2 g). Each RI was obtained from the local market in Cairo and then subjected to a library search by comparison with cultivated in the Botanical Garden of the Faculty reference RI values previously stored in a data of Pharmacy, Zagazig University and were col base in the Institut für Pharmazeutische Biologie, lected during the flowering and fruiting stages in Universität Heidelberg (Table I). March and May 1997, respectively. Flowering L. hartwegii plants were collected from Botanical GLC-MS analysis Garden of the Faculty of Agriculture, El- Minufiya A Carlo Erba HRGC 4160 gas chromatograph University, Egypt in March 1997. Voucher speci equipped with a fused silica column (OV1; 30 m, mens have been deposited both in the Institut für 0.3 mm ID). The capillary column was directly Pharmazeutische Biologie, Universität Heidelberg coupled to a quadrupole mass spectrometer Finni- and in the Department of Pharmacognosy, Faculty gan MAT 4500. El-mass spectra were recorded at of Pharmacy, Zagazig University, Egypt. 40 eV. Condition: injector 250 °C; temp, program 70-300° C, 6 ° C /min or 150-300° C, 6 ° C /min. Extraction Split ratio 1 : 20; carrier gas He 0.5 bar. About 20 g plant material was macerated in Screening for antimicrobial activity 90% ethanol for 24 h. After filtering off the insolu ble material, the filtrate was evaporated under re Microorganisms were Staphylococcus aureus, duced pressure. About 680 mg residue was ob Bacillus subtilis (Gram positive bacteria); Escher tained from L. albus seeds (3.4%) and 370 mg ichia coli, Klebsiella pneumoniae (Gram negative from aerial parts (1.85%); from L. varius 384 mg bacteria); Candida albicans and Aspergillus flavus (1.92%) were extracted from seeds and 242 mg (fungi). The microorganisms were obtained from from aerial parts (1.21%). Half of the residue was the stock cultures of the Department of Microbiol used for antimicrobial tests, the other half for al ogy, Faculty of Pharmacy, Zagazig University. An kaloid extraction. timicrobial activity was assayed via the agar diffu About 100 to 340 mg of the residue was dis sion method. Small cups were taken out of the solved in 15 ml 0.5 n HC1 and defatted with 100 ml agar which could take approx. 60 ^ 1 of extracts. dichloromethane. The homogenate was then ad Each cup was filled accurately with 50 (il extracts justed to pH 10 with ammonia (25%). Alkaloids (25 mg residue of total or alkaloidal extracts were were extracted by solid phase extraction using Ex- dissolved in 1 ml dimethylformamide, DMF) as trelut columns (Merck. Darmstadt) and dichloro well as DMF as a control. The plates were incu methane as an eluent. Different plant parts were bated overnight at 37° C for bacteria and 30° C analysed by GLC in order to compare the respec for fungi. A. El-Shazly and M. Wink • Quinolizidine Alkaloids 23 Table I. Mass spectral data (M+, base peak) of quinolizidine alkaloids from Egyptian species of L. a. albus, L. varius orientalis, L. hartwegii and L. densiflorus. No. Alkaloid RI M+ Base Ref. peak 1 Lupinine 1422 169 83 1 , 2 2 Tryptophol 1580 161 130 3 3 Gram ine 1620 174 130 3 4 Sparteine 1785 234 137 4, 2 5 ß-Isosparteine 1830 234 137 5, 6 6 11,12-Dehydrosparteine 1840 232 134 2, 7 7 Ammodendrine 1865 208 165 8 , 9 8 A lbine 1900 232 191 1 0 , 1 1 9 Dihydroalbine 1915 234 193 1 0 N-Methylcytisine 1955 204 58 9, 12 1 1 Epiaphyllidine 2 0 2 0 246 98 2 1 1 2 Isoangustifoline 2033 234 193 12, 13 13 Tetrahydrorhombifoline 2050 248 207 12, 14 14 Epiaphylline 2055 248 136 15, 16 15 Dehydroangustifoline 2070 232 1 2 0 1 2 16 Angustifoline 2083 234 193 1 2 , 16 17 Dihydromultiflorine 2 1