Occurrence of Secondary Metabolites in Tepals of Asphodelus Ramosus L. C
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This article was downloaded by: [Professor S. Rhizopoulou] On: 03 May 2014, At: 01:35 Publisher: Taylor & Francis Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK Plant Biosystems - An International Journal Dealing with all Aspects of Plant Biology: Official Journal of the Societa Botanica Italiana Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/tplb20 Occurrence of secondary metabolites in tepals of Asphodelus ramosus L. C. Chimonaa, A. Kariotibc, H. Skaltsab & S. Rhizopouloua a Department of Biology, University of Athens, Greece b Department of Pharmacognosy and Chemistry of Natural Products, University of Athens, Greece c Department of Pharmaceutical Sciences, University of Florence, Italy Accepted author version posted online: 02 Apr 2013.Published online: 29 Apr 2013. To cite this article: C. Chimona, A. Karioti, H. Skaltsa & S. Rhizopoulou (2014) Occurrence of secondary metabolites in tepals of Asphodelus ramosus L., Plant Biosystems - An International Journal Dealing with all Aspects of Plant Biology: Official Journal of the Societa Botanica Italiana, 148:1, 31-34, DOI: 10.1080/11263504.2013.790851 To link to this article: http://dx.doi.org/10.1080/11263504.2013.790851 PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http:// www.tandfonline.com/page/terms-and-conditions Plant Biosystems, 2014 Vol. 148, No. 1, 31–34, http://dx.doi.org/10.1080/11263504.2013.790851 Occurrence of secondary metabolites in tepals of Asphodelus ramosus L. C. CHIMONA1, A. KARIOTI2,3, H. SKALTSA2, & S. RHIZOPOULOU1 1Department of Biology, University of Athens, Greece; 2Department of Pharmacognosy and Chemistry of Natural Products, University of Athens, Greece and 3Department of Pharmaceutical Sciences, University of Florence, Italy Abstract Major processes contributing to subtleties of ephemeral flowers of Asphodelus ramosus are related to chemical constituents detected in tepals which expand during cold and wet seasons in the eastern Mediterranean. Luteolin, caffeic acid, chlorogenic, and p-hydroxy-benzoic acids are the main constituents, whereas alkanes, ketones, and fatty acids appear in low amounts. Keywords: Asphodelus ramosus, flower, secondary metabolites, tepals Introduction 2006; Vagashiya et al. 2011). In contrast, very little information has been obtained regarding the Asphodelus ramosus L. (Asphodelaceae) is a perennial secondary metabolites of flowers, which contribute geophyte, consistent floristic element of the Medi- to defensive functions (Mu¨ller & Riederer 2005), terranean ecosystems and the most common species whereas a phytochemical analysis of tepals of of the genus Asphodelus with branched inflorescences A. ramosus has not hitherto been reported. (Narducci 1957;Dı´az Lifante & Valde´s 1994;Dı´as Lifante & Aguinagalde 1996;Dı´as Lifante & Valde´s 1996). The flowering period of A. ramosus starts in Materials and methods February and ends in March, coinciding with the Plant material rainy and cold seasons in the eastern Mediterranean. The ephemeral, actinomorphic flowers of A. ramosus Flowers of A. ramosus were randomly collected early open acropetally by exhibiting six whitish tepals on in March, from natively growing plants in the flowering stalks that may be up to 1 m long Campus of the University of Athens (UoA) in Greece (250 m a.s.l., 37857.60N, 23847.10E), where Downloaded by [Professor S. Rhizopoulou] at 01:35 03 May 2014 (Argiropoulos 2009). This study was conducted in an effort to identify monthly precipitation was estimated at 50 mm and secondary metabolites related to adaptations of average temperature was 148C. The plant material delicate tepals of A. ramosus exposed to unfavorable, was identified by Assistant Professor Dr Theophanis abiotic, environmental conditions in the eastern Constantinidis (Department of Biology, Section of Mediterranean. In the subterranean tissues of other Systematics & Ecology, University of Athens, Asphodelus species (i.e., A. albus Mill., A. acaulis Desf., Greece). A voucher specimen (UoA CR-14) has A. fistulosus L., and A. microcarpus Viv.), lipophilic been deposited at the Herbarium of the University of anthranoid aglycones (chrysophanol, asphodeline, and Athens, Greece. 0 O,7 -bichrysophanol), b-sitosterol-b-D-glucoside, and 0 aryl coumarin glycoside (asphodelin A 4 -O-b-D- glucoside) have been identified (Hammouda et al. Phytochemical analysis 1972;VanWyketal.1995;El-Seedi2007). Also, Dried tepals of flowers were ground (19.6 g) alkaloids have been investigated in the leaves of and extracted with a mixture of MeOH–H2O (5:1) A. aestivus Brot. and A. tenuifolius Cav. (C¸ alıs et al. (3 £ 240 ml) under agitation in a shaker for 90 min, the Correspondence: S. Rhizopoulou, Department of Botany, Faculty of Biology, National and Kapodistrian University of Athens, Panepistimiopolis, Athens 15781, Greece. Tel: þ 30 210 7274513. Fax: þ 30 210 7274702. Email: [email protected] q 2013 Societa´ Botanica Italiana 32 C. Chimona et al. combined extracts were filtered and concentrated to Packard 6890 gas chromatograph fitted with a fused dryness in vacuum. The obtained residue (14.0 g) silica HP-5 MS capillary column that was tempera- was prefractionated by vacuum liquid chromatog- ture programed from 508C to 2808Catarateof raphy (VLC) over silica gel (5.5 cm £ 10 cm) using 48Cmin21. Helium was used as carrier gas at a flow 21 eluents mixtures of cycloxexane–CH2Cl2–MeOH– rate of 0.8 ml min . The chromatograph was H2O (100:0:0:0, 0:95:5:0–0:20:80:0, 0:0:50:50) of coupled to a MS 5973 mass selective detector at increasing polarity to yield 11 fractions (A–K) of 70 eV. The spectra were taken in electron impact 300 ml. Fraction A (6.3 mg, eluted with cyclohexane) mode. Retention indices for all compounds were was analyzed through Gas Chromatography-Mass determined according to the van den Dool approach Spectrometry (GC-MS). Fractions F and G were using n-alkanes as standards. The identification of the combined (300 mg eluted with CH2Cl2–MeOH, compounds was based on comparison of their mass 80:20 and 70:30, respectively) and were further spectra with those of Wiley and NBS Libraries purified by column chromatography (CC) over (Massada 1976) and those described by Adams Sephadex LH 20 eluted with CH2Cl2–MeOH (2006), as well as on comparison of their retention (20:80) and yielded luteolin (205.4 mg). Fraction I indices with literature values. (4.5 g eluted with CH2Cl2–MeOH, 20:80) was further purified by CC over Sephadex LH 20 Results (MeOH) and afforded nine fractions (I1–I9). Frac- tion I5 was identified as chlorogenic acid (4.5 mg). Chromatographic separation of the polar extract of 21 Fraction I2 (373.9 mg) was further purified by CC tepals of A. ramosus yielded luteolin (0.5 mg g d.w.), 21 over silica gel using as eluents mixtures of CH2Cl2– caffeic acid (0.6 mg g d.w.), chlorogenic acid 21 MeOH–H2O (from 95:5:0.1 to 70:30:3) and yielded (0.22 mg g d.w.) and p-hydroxy-benzoic acid 21 seven fractions (IB1–IB7). Fraction IB6 was identified (0.15 mg g. d.w.). Results from GC–MS analysis of as p-hydroxy-benzoic acid (3.2 mg). Fraction I4 the nonpolar constituents eluted with cyclohexane (62.4 mg) was further purified by High Performance (fractionA)aregiveninTable I. Notably, several Liquid Chromatography (HPLC) (AcOH 5%– hydrocarbons (54.6%) were identified in homologous MeOH, 65:35) and yielded 11 fractions (IC1– series, i.e., alkanes (C12 –C29: 51.6%), alkene (C20: IC11). Fraction IC4 was identified as caffeic acid 3%), and related aldehydes (C9–C24:18.1%).In (11.4 mg). 1H, 13C, and 2D NMR spectra were addition, two ketones and two fatty acids were present in recorded in CD3OD on Bruker DRX 400 and appreciably low amounts (0.4% and 0.5%, respect- Bruker AC 200 (50.3 MHz for 13C NMR) instru- ively). Concerning the identified hydrocarbons, doc- ments at 295 K. Chemical shifts are given in ppm (d) osane and tricosane were the most abundant (Table I). and were referenced to the solvent signals at 3.31 ppm and 49.5 ppm for 1Hand13CNMR, Discussion respectively. Correlation Spectroscopy, Heteronuclear Single Quantum Coherence, and Heteronuclear Thirty-eight secondary metabolites were detected in Multiple Bond Correlation were carried out using tepals of ephemeral flowers of A. ramosus that standard Bruker microprograms. Infra Red spectra blossom during the cold and rainy seasons in were obtained on a Perkin-Elmer PARAGON 500 Mediterraneanregion(Table I). Among them Downloaded by [Professor S. Rhizopoulou] at 01:35 03 May 2014 FT-IR spectrophotometer. Ultraviolet-Visible spectra luteolin, which is present in leaves of A. ramosus were recorded on a Shimadzu UV-160A spectropho- and floral tissues of other species, can enhance tometer, according to Mabry et al.