الفهرس 
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Abstract
Phytochemical and Biological Study of Certain Plants Belonging to Genus
Pelargonium Family Geraniaceae Cultivated in Egypt
Introduction
The genus Pelargonium (family: Geraniaceae) comprises more than 280 species of perennial small
shrubs with scented leaves of various odours, which range from pleasantly fruity or floral to rather
balsamic. Pelargonium species are native to South Africa and commercially grown for production
of essential oil in Egypt. Pelargonium species were also successfully employed in modern
phytotherapy for their antioxidant, antimicrobial and immunomodulatory effects. Other reported
biological activities were nematocidal activity, insect repellent effects, and tropical haemostatic
effects. The reported pharmacological studies on genus Pelargonium indicated that the essential
oils could be used as relaxant agents in aromatherapy products due to their spasmolytic activities.
Reviewing the current literature reports on the plants were scanty, so it deemed interesting to
investigate the chemical constituents and biological activities of the plants, aiming to verify the
possible medicinal use. The aim of this thesis is to investigate both the biological activity and
phytochemical constituents of Pelargonium x fragrans Willd. and Pelargonium peltatum L’Hérit.
The present study include four parts
1. Part I: Phytochemical screening of P. peltatum and P. x fragrans.
2. Part II: Study of the Essential oils of P. x fragrans.
► [Study of the antispasmodic active]
► [Study of the antimicrobial activity]
► [Study of the antioxidant activity] 4. Part IV ►Investigation of the phenolic content of ethyl acetate fraction of P. peltatum.
► Standardization of polyphenol content in Pelargonium peltatum and Pelargonium x
fragrans Extracts
Part I: Phytochemical screening of P. peltatum and P. x fragrans:
Air dried samples of aerial parts of Pelargonium x fragrans and Pelargonium peltatum were,
separately, screened for : carbohydrates and/or glycosides, unsaturated sterols and/or tritepenes,
antharquinones , cardiac glycosides , tannins , flavonoids , saponins, alkaloids and/or nitrogen bases
and cyanogenic glycoside.
The screening tests indicated that:
I. Aerial parts of P. peltatum and P. x fragrans were rich in carbohydrates and/or glycosides,
hydrolysable tannins, free and combined flavonoids, as well as sterols and/or triterpenes.
II. Investigated aerial parts were free from alkaloids and/or nitrogenous bases, free and combined
anthraquinones, as well as cardiac and cyanogenic glycosides.
III. Determination of successive extractives and their TLC examination for P. peltatum and P. x
fragrans revealed that:
1. The petroleum ether extracts of P. peltatum & P. x fragrans were obtained in yields of
(3.8 gram, 3.8 %) and (3.2 gram, 6.4 %) respectively, while the chloroform extracts were
(0.3 gram, 0.3 %) and (4.8 gram, 2.4 %), respectively and were distinguished by the presence of
steroidal and/ or terpenoidal compounds.
2. The yield of the ethyl acetate (5.3 gram, 5.3 %), (8.4 gram, 4.2 %) and the n-Butanol (11.7 gram,
11.7 %) (17 gram, 8.5 %) extracts of P. peltatum & P. x fragrans yielded respectively and they
were characterized by the presence of phenolic compounds (flavonoids, tannins).Part two: Study of the essential oils
Study of the essential oils of Pelargonium x fragrans and Pelargonium peltatum
Hydrodistillation of the leaves and flowers of P. x fragrans cultivated in Egypt yielded 3% and
2.5% (v/w of fresh plant) of yellowish green essential oils, having a spicy odour. GC/MS analysis
led to identification of 29 and 32 components, based on retention indices and mass spectral data, in
the two samples representing 99.0 % and 99.2 % of the total oils, respectively. Monoterpenoids
content were predominant in the oil of the leaves than in the flowers representing 38.2 % and 23.8
%of the total oils. Among which hydrocarbon were 18.2 % and 17 % followed by oxygenated
monotepenoids constituting 20 % and 6.8 %, respectively. Sesquiterpenoids reached only 20.6 % in
the leaves oil but were higher in the oil of the flowers (51.4 %) of which the hydrocarbon constitute
6.9 % and 46.5 % and oxygenated sesquiterpenoids amounted 13.7 % and 4.9 % respectively, of the
total oils. Phenyl propanoids represent (40.3 % and 24 %) in the oils of leaves and flowers,
respectively. Major monoterpene hydrocarbons detected were α-pinene (6.1 %), m-cymene (4.8 %),
α-Thujene (2.3 %), sabinene (1.4 %), β-pinene (2.5 %). Oxygenated monoterpenes mainly
represented by fenchone (7.1 %), linalool (4.9 %), 1,8- cineole (2.9 %), terpinen-4 (1.4 %). Further,
β-caryophyllene (25 %), bicyclogermacrene (2.2 %), δ-cadinene (1.8 %) were the major
sesquiterpene hydrocarbons in P. x fragrans oil. Phenyl propanoids were represented mainly by
methyl eugenol (24.8 %), trans-anethole (11.9 %) and methyl chavicol “estragole” (3.6 %). On the
other hand; main oxygenated sesquiterpenes of P. x fragrans oil were spathulenol (10.9 %) and
caryphyllene oxide (4.6 %).
Part three: Biological studies
► Study of the antispasmodic activity of P. x fragrans:
The antispasmodic activity of the essential oil of the aerial parts of P. x fragrans was carried out
on the gastrointestinal smooth muscles of a rabbit and was constructed in the presence of the
submaximal dose of Ach. The tested oil exhibited an interesting inhibition of the-spasmolytic
acetylcholine induced- contraction of the isolated rabbit jejunum.
.►Study of the antimicrobial activities of P. peltatum and P. x fragrans:
The potential antimicrobial activities of the extracted fractions of P. peltatum, P. x fragrans and the
essential oil of P. x fragrans, were studied through determination of thier zones of inhibition by agar
well method. MICs were also determined for the essential oil using clinical isolates of Gram positive
(Bacillus subtillus and Staphyllococcus aureus), Gram negative (Pseudomonaus aureginosa and
Escherichia coli) bacteria as well as clinical fungal isolates (Aspergillus niger and Candida
albicans). Standards with the concentration of 1 mg/ml were used as positive controls miphincol for
gram positive, keflix for Gram negative bacteria , flucoral for fungi. The antibacterial susceptibility
screening revealed that all microbial strains used in the present study were susceptible to the extracts
of both species P. peltatum and P. x fragrans to a varying degree, showing moderate activity against
all investigated strains. The petroleum ether fraction showed strong antifungal activity against
A. niger. Minimum inhibitory concentrations (MIC’s) of the oils of P. x fragrans leaves and flowers
ranged from 18.75 to 150 µg/mL and from 37.5 to 150 µg/mL against fungi. The highest
antibacterial activity observed for the oil was against E.coli ( 18.75 µg/mL). on the other side the
P. x fragrans hydrosol showed moderate activity against E. coli and P. aeruginosa with no obvious
effect to the other tested micro organism.
►Study of the antioxidant activities of P. peltatum and P. x fragrans:
The total ethanolic extracts of P. x fragrans and P. peltatum and their fractions thereof (petroleum
ether, chloroform, ethyl acetate and ethyl alcohol) were subjected to DPPH photometric assay for
their radical scavenging activities. The most effective antioxidant fractions of P. peltatum and P. x
fragrans was the n-Butanol fraction (85.2 % and 85 %) at the concentration of 0.375 µg/ml
followed by the total ethanolic extracts (84.62 % and 78.1 %) respectively, with the same
concentration compared to the standard reference ascorbic acid which showed a significant radicals
scavenging potential (79.1 %) in the concentration of 1 µg/ml. The high activity of the n-Butanol,
ethyl acetate fractions and the total extracts is probably due to the presence of phenolic substances,
where DPPH free radical abstracts the phenolic hydrogen of the electron donating molecule.Part IV:
►Investigation of the phenolic content of ethyl acetate fraction of P. peltatum
The total ethanolic extract of the aerial parts of P. peltatum was fractionated using solvents of
different polarities (petroleum ether, chloroform, ethyl acetate and n-Butanol). The ethyl acetate
fraction was fractionated on polyamide column and eluted with water with increasing concentrations
of MeOH. Fractions were collected and some of which were directly purified on sephadex LH-20
column to afford compound (C1) gallic acid and (C2) methyl gallate. The other fractions were
loaded over cellulose chromatographic column and purified on sephadex LH-20 column to afford
compound (C3) which was tentatively identified as 1,3,6-Tri-O-galloyl-β-D-glucopyranose and (C4)
is 1,2,3,4 ,6 penta galloyl -β-D- glucopyranose.
► Standardization of polyphenol content in Pelargonium peltatum and Pelargonium x fragrans
extracts
TP (total polyphenol content), calculated as gallic acid, of the aerial parts of P. peltatum and P. x
fragrans estimated in their respective aqueous exacts by Folin-Ciocalteu colorimetric assay
revealed that they were rich in polyphenols, where it was found to be 12.46 and 12.67 mg GAE/g
dry weight respectively. The results indicated that there is a linear correlation between polyphonic
content and antioxidant activity of the plants.