الفهرس 
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Abstract
The present study aims to introduce a simple, rapid and economical
route to synthesize silver nanoparticles (AgNPs) using aqueous and
methanolic extracts from two medicinal plants; ginger and lemon grass as
reducing and stabilizing agents
In this respect we determined the chemical composition of both aqueous,
methanolic extracts, and essential oils. AgNPs synthesis was inferred by
the change of color from yellow to brown. The size, morphology and
stability of AgNPs depend on the active ingredients in the extracts.
AgNPs size and morphology were characterized using UV-visible
analysis and transmission electron microscopy (TEM). We investigated
the ability of these extracts to protect liver, kidney and heart of rats
against oxidative stress caused by H2O2 (0.5 % in drinking water). Finally
we evaluated antibacterial effect of (AgNPs), methanolic extracts and
essential oils against some pathogenic bacteria.
The results obtained can be summarized in the following points:
1- Chemical composition of ginger: -
moisture (15%), protein (7.1%), lipids (6.7%), carbohydrates (42 %),
fibers (37 %), and ash (5.3 %).
2- Chemical composition of lemon grass:
moisture (33%), protein (3.8%), lipids (8.66%), carbohydrates (33%),
fibers (39.0%), and ash (13%).
3- The essential oil of ginger and lemon grass were analyzed by Gc/Ms to
determine their components, Twenty four compounds were identified in
ginger oil. The main compounds were L-sesquiphellandrene (26.1%) and
Zingiberen (12.3%). Also twenty nine compounds were identified in
lemon grass essential oil. The main compounds were Citral A (Geranial)
(36.6) % followed by Citral B (Neral) (32.2%), β-myrcene(9.1%), and
Nerol (5.1%)
4- Silver nano particles were synthesized using both of aqueous and
methanolic extract of each plant the maximum peak ranged from 400 to
450 nm as measured by UV-visible spectrophotometer. The minimal size
of prepared (AgNPs) ranged 13-50 nm under Transmission Electron
Microscopy (TEM)
5- Total phenolic components: lemon grass essential oil recorded the
highest value (339) ppm and lowest value was (77) ppm for lemon grass
aqueous extract, but in the same time ginger methanolic extract recorded
the highest value of flavonoids (25.1) ppm however ginger aqueous nano
record the lowest value (5.7) ppm.
6- Total antioxidant capacity was determined and lemon grass methanolic
extract silver Nano particles record the highest value (512) μmol ascorbic
equ but lemon grass aqueous extract record the lowest value (145) μmol
ascorbic equ in concentration 100%, in the same tine Ginger methanolic
extract record the highest value of reducing power (467) mg/ml and the
lowest value was (356) mg/ml for ginger oil.
7- In this aspect we designed bio experiment on rats to evaluate the
efficiency of these extracts to protect liver, kidney and heart of
experimental animals against oxidative stress caused by addition of 0.5%
H2O2 in drinking water. The study showed that; all of silver nano extracts
recorded the highest effect followed by essential oil and methanolic
extracts from both of ginger and lemon grass.
8- Antibacterial activity of AgNPs, Methanolic extracts and oil – was
determined by testing minimal inhibitory concentrations (MIC) against
common pathogenic bacteria including:
-Gram negative bacilli: Escherichia coli, Klebsiella pneumoniae,
Salmonella para typhi B, Salmonella typhi, Shigella species and Proteus
mirabilis , and -Gram positive cocci: Staphylococcus aureus, Coagulase
negative Staphylococcus and Enterococcus
Recommendations:
1- Medicinal and aromatic plants should be used in fooding and
drinking because its contain a lot of natural antioxidant.
2- Plant extracts can be used as drugs alternates because its useful effect
3- Green synthesis of silver nanoparticles is simple, rapid, economical
and can be used in large scale so that we recommended that do
another experiments on pigs and Monkeys preparing to using silver
nanoparticles in human treatment.
4- Nowadays world suffering from multi drud resisitant bacteria so
we recommended that using silver nanoparticles as antibiotic
alternate in the future.
5- Nanoparticles can make a huge trend in many areas, especially in
field of Biochemistry and modern technology.