الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Narcissus pseudonarcissus L., commonly known as wild daffodil or lent lily, is among the first phytochemically and biologically studied species of the family Amaryllidaceae. This plant is natively distributed throughout Western Europe from Spain and Portugal to England. Wild daffodil is a bulbous perennial monocotyledonous flowering herb with ovoid, 2-3 cm long bulbs carrying slightly greyish-green strap-like, erect, narrow leaves that are 10‒35 cm long. Blooming of the bulbs usually starts in the early to mid-spring, forming cup-shaped flowers that are 4‒6 cm in length with a pale yellow perianth and a darker central trumpet. Besides its ornamental uses owing to the fragrant and brilliant flowers, N. pseudonarcissus also possesses various significant biological activities. Phytochemical research on this species has yielded a diversity of metabolites, primarily alkaloids, with promising biological potential. The present study of N. pseudonarcissus bulbs included:
Chapter I
Preliminary phytochemical screening of the powdered bulbs of
N. pseudonarcissus L.
The obtained findings revealed that N. pseudonarcissus bulbs contained alkaloids and/or nitrogenous compounds, carbohydrates and/or glycosides, flavonoids, and sterols and/or triterpenes, while they are free of crystalline sublimates, saponins, tannins, cardiac glycosides, anthraquinones.
Chapter II
Investigation of the saponifiable and unsaponifiable matters of N. pseudonarcissus L. bulbs
GC-MS analysis of the saponifiable matter of the pet. ether extract of N. pseudonarcissus
L. bulbs resulted in the identification of a total of 37 compounds, representing 97.02% of the total saponifiable fraction, with a relatively higher percentage of unsaturated fatty acids (44.65%) versus their saturated counterparts (40.91%). Methyl linoleate (23.95%) was the
major identified fatty acid methyl ester, which also represented about half the total content of unsaturated fatty acids, followed by methyl oleate (14.14%), methyl palmitoleate (3.08%), whereas methyl palmitate, constituting 20.25%, was the major identified saturated fatty acid methyl ester, followed by methyl stearate (4.75%) and methyl arachidate (4.31%). Additionally, a group of alkylbenzenes has been also detected and constituted 11.76% of the total identified compounds.
GC-MS analysis of the unsaponifiable matter of the studied plant bulbs displayed a total of 14 components, of which 13 compounds representing 98.02% of the total unsaponifiable matter were identified. The identified compounds comprised both oxygenated (18.53%) and non-oxygenated metabolites (81.47%). N-substituted amines, constituting 70.12% of the total identified compounds, were the most predominant species among both groups of constituents, with N,N-dimethyl-1-dodecanamine (45.22%) being the major identified metabolite. Besides, some long-chain hydrocarbons, such as heptacosane (11.10%) and dotriacontane (3.02%), were identified among the group of non-oxygenated compounds. On the other hand, the oxygenated metabolites accounted for 18.53% of the total unsaponifiable matter content and included phenylpropanoids (3.43%), fatty acid methyl esters (6.97%), and phthalate derivatives (1.26%).
Chapter III
Extraction, fractionation, and isolation of the constituents of N. pseudonarcissus L. bulbs
The air-dried powdered bulbs (2 kg) of N. pseudonarcissus were extracted with ethanol (95%) at room temperature and the solvent was evaporated to dryness under vacuum. The crude ethanol extract (255.0 g) was suspended in water-methanol (1:1) in a separating funnel and defatted with light pet. ether. The aqueous solution left was acidified with tartaric acid (10%) and extracted with EtOAc. The mother liquor was then completely basified by addition of sodium carbonate till saturation and re-extracted with EtOAc. Finally, the obtained fractions were concentrated under vacuum to give the pet. ether fraction (Fr. I, 27.0 g), the acidic EtOAc fraction (Fr. II, 47.0 g), the basic EtOAc fraction (Fr. III, 10.0 g), and the aqueous fraction (Fr. IV, 155 g). During acid-base fractionation, compound 1 was obtained as white needles (280.0 mg).
A part of Fr. I (25.0 g) was further fractionated by VLC using pet. ether-EtOAc gradient mixtures to provide five subfractions (I1-I5) that were further chromatographed on several silica gel columns using pet. ether-EtOAc isocratic and gradient elution techniques. Compounds 2 and 3 were finally obtained after successive purification steps of I1-F-2, whereas compounds 4 and 5 were obtained from I2-F-2. Also, compounds 6 and 7 were isolated after chromatographic purification of I3-F-3, and I3-F-4, respectively, along with compounds 8, 9, and 10 from I3-F-5, while the purification of I4-F-1 and I4-F-2 afforded compounds 11 and 12, respectively.
Chapter IV
Identification of the isolated compounds from N. pseudonarcissus L. bulbs
Structures of the isolated compounds were determined using a variety of spectroscopic techniques, including 1H-NMR, APT, EI-MS, and ESI-MS analyses, as well as by comparison of their physical, chemical, and chromatographic properties with those published in the literature. Different isolated compounds are listed in
Chapter V
Estimation of the total phenolic and flavonoid contents of N. pseudonarcissus L. bulbs
(1) Estimation of TPC:
The content of total phenolics of the TEEFs was assessed using the Folin–Ciocalteu technique. The highest TPC was detected in the acidic EtOAc fraction (5.56 ± 0.24 mg GAE/g dry weight).
(2) Estimation of TFC:
Comparative assessment of the TFC of the TEEFs revealed that the acidic EtOAc fraction contains the highest TFC (1.30 ± 0.02 mg QE/g dry weight) among the studied samples.