الفهرس 
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Abstract
Family Brassicaceae (Cruciferae or the mustard family) is considered as one of the largest Angiosperms families.
It includes 340 genera and more than 3350 species, distributed throughout the world, chiefly in temperate regions of the northern hemisphere.
In Egypt, family Brassicaceae is represented by about 120 species belonging to 55 genera.
Genus Lepidium is the most medicinally important genus of family Brassicaceae comprising more than 150 species, distributed throughout almost all temperature and subtropical regions of the world.
It is represented in Egypt by 3 species namely Lepidium latifolium, Lepidium sativum and Lepidium aucheri.
Among the most recognized Lepidium species in folk medicine is Lepidium Sativum L., commonly named as Garden Cress or Hab Al Rashad.
<Literature survey revealed that Lepidium sativum L. belongs to family Brassicaceae (Cruciferae).
It has been widely used in folk medicine as diuretic. Plant was used in the treatment of inflammation and cancer.
The work presented in this thesis represents plant tissue culture using medicinal plant (Lepidium sativum L.) and biological screening of anti-inflammatory, antimicrobial, anticancer and antioxidant activities of its different extracts. Moreover, green synthesis of silver nanoparticles was applied using the plant aqueous extract.
2. Aim of the work The attempted work in this thesis is optimization of tissue culture experiments to ensure establishment of callus cultures from explants and liquid cultures (suspension cultures) from static cultures for Lepidium sativum L. using different growth regulators, preparation of different extracts for the obtained cultured plant, biological evaluation of the obtained extracts and comparing the biological activities for both tissue cultured and cultivated plants.
Additionally, we had synthesized silver nanoparticles using the plant aqueous extract instead of toxic chemical and physical methods.
3.
Plant tissue culture of Lepidium sativum L. with different growth regulators
Plant tissue culture systems represent a potential renewable source of valuable medicinal compounds which cannot be produced by microbial cells or chemical synthesis.
<Thus, this technology was applied on the important aromatic plant Lepidium sativum L. which can be widely used for medicinal and non- medicinal purposes all over the world.
In this thesis, nine different extracts from different parts of plant which are seed, leaf and seven leaf callus’ extract cultivated using different growth regulators were prepared. 2,4-D is the most important plant growth regulator to obtain callus of good quality and in a short time.
3.1 Anti-inflammatory activity of the tested Lepidium sativum L. different extracts using HRBC Membrane - Stabilizing Method
<Here, a biological screening of anti-inflammatory activity for the different tested extracts was performed.
All of them showed anti-inflammatory activity in vitro by HRBC Membrane-Stabilizing Method using Indomethacin as reference standard.
Seed and leaf extracts were the most effective extracts nearly similar to Indomethacin.
<3.2 Antimicrobial activity of tested Lepidium sativum L. different extracts using agar diffusion method An agar diffusion method was applied using Gentamicin (10 mg/mL) as a standard antibacterial drug, while Ketoconazole was used as a standard antifungal drug for testing different extracts against different microorganisms; bacterial and fungal strains. Cultivated leaf callus extract using 1 mg/mL of 2,4-D had potential against all the tested bacterial and fungal strains.
<Seed extract was the most effective against all bacterial organisms, higher than Gentamicin standard antibacterial drug in all strains.
<For fungal strains, the leaf extract showed the highest activity against Candida albicans, while for Asperigullus flavus, the leaf callus extract cultivated using 1 mg/mL of adenine was the most active.>
<Both were higher than Ketoconazole standard antifungal drug.
<3.3 Cytotoxic activity of the tested Lepidium sativum L. different extracts on hepatocellular carcinoma (HepG-2) and grade IV adenocarcinoma (PC-3)>Cancer research is a compromising area for work. Discovery of new safe cytotoxic agent is paid a great effort.
In this thesis, different extracts were tested for their cytotoxicity against two different cancerous cell lines; hepatocellular carcinoma (HepG-2) and grade IV adenocarcinoma (PC-3).
< Lepidium sativum L. leaf calli extracts obtained by 1 mg/mL of NAA and 1 mg/mL of 2,4D showed the best anticancer activity with IC50 382.2 and 113.6 μg/mL on HepG-2 and PC-3 cells respectively.
<<3.4 Antioxidant activity of the tested Lepidium sativum L. different extracts using DPPH assay.
<Natural products from dietary components and medicinal plants are known to possess antioxidant activity, there are epidemiological evidences correlating higher intake of foods with antioxidant abilities to lower the incidence of various human mortalities.
<We performed, here screening of the antioxidant activity for the different tested extracts, all of them showed antioxidant activity in vitro by reducing the absorbance of DPPH radical using Ascorbic acid as reference standard.
< Seed extract was the most active extract with IC50 10 μg/mL nearly similar to that of Ascorbic acid.
<4. Lepidium sativum L. phyto-synthesized silver nanoparticles with potential antifungal and cytotoxic activities
Since bio-inspired synthesis of nanoparticles has received immense attention recently, specifically green synthesis due to its tremendous advantages, we synthesized silver nanoparticles using aqueous extracts of the seed and leaf of Lepidium sativum.
<characterization using UV-Visible spectral analysis, Scanning electron microscopy and Zeta potentiometry was done for the phytosynthesized silver nanoparticles.
<UV-Vis absorption spectroscopy recorded peaks at 420 and 440 nm for nanoparticles synthesized by Lepidium sativum L. seed and leaf, respectively.
< Scanning electron microscopy confirmed the spherical and polydispersed nature of the formed nanoparticles.
< Zeta potentiometry demonstrated an average diameter of 150.2 and 111.7 nm with a zeta potential of -15.6 and -20 mv, for nanosilver phytosynthesized by Lepidium sativum L. seed and leaf, correspondingly.
< The phytofabricated nanosilver exhibited a significant antifungal effect against Candida albicans as conveyed by inhibition zones and minimum inhibitory concentration (MIC) and demonstrated cytotoxic effect using MTT assay against MCF-7 breast cancer cell line.
AgNPs synthesized using Lepidium sativum L. seed extracts exhibited a higher antifungal effect with an inhibition zone of 14±0.57 mm and an MIC of 1.75 ppm versus an IZ of 11.67±0.33 mm and an MIC of 2.03 ppm for those fabricated by Lepidium sativum L. leaf.
For cytotoxic effect, the relevant IC50 values were 20.1 ppm and 9.3 ppm for nanoparticles synthesized by aqueous extract of seed and leaf, respectively