hi everyone i am Mohammed Almutairi my
topic is the green synthesized
zinc oxide nanoparticles and their
antibacterial activity
um
first of all what's green synthesized uh
synthesized nanoparticles
green synthesized nanoparticles are a
combination of
blends of their uh or their metabolites
with inorganic chemical in order to
replace
to reduce their toxicity and
nanoparticles are verticals their size
range between 1 to 100 nanometer in
diameter
this technology has been emerged as an
important
modern area of research because surface
ratio to volume ratio
which causes them to become reactive
uh to some other molecules
the most synthesized metal is silver
gold
zinc and zinc zinc oxide and titanium
our metal is zinc oxide which causes uh
which uses sorry
uh in some products such as cosmetic
and sunscreen cream it's thought that
the plant may enhance nanoparticles
functions
or the reverse nanoparticles may enhance
plant
function in this case zinc oxide and
verticals may enhance
nano particles however green synthesized
uh depends on some factors which are
temperature
solvent pressure and ph whereas
from blend it's depend on fetal
chemicals such as flavonoids peniles or
other active chemicals
potential basic uh applications from
green synthesis nano particles
are a reduction of hazard waste
designing of
safer chemical and more importantly
alternative to antibiotic resistant
and antibiotic
and uh preservatives uh the
antimicrobial activity of nano particles
depend on
size of particles because uh the
as we say um ratio to uh surface ratio
to volume ratio
at critical point also the functional
group of plants
exposed on nano particles
the aim of my study are evaluating the
green synthesized zinc oxide
nanoparticles antibacterial activities
again is e coli 0157: H7 Sakai
which is a common food borne pathogen as
well B. cereus R3054 also food borne pathogen and spores
forming
and the marine bacteria Aliivibrio finisterrensis
strains
uh A4 A9 A15 A21
A33 and A37
which are very drug resistant also
it grows grows in farm atlantic salmon
to a high level and it's thought to
potentially cause
uh cause dice abuses in the gut of
salmon during the summer
the second aim of the study is the
reduction of
zinc uh salt into zinc oxide using
Tasmania
lanceolata and kunzea ambigua leaf extract
these plants are industrially used for
essential oil extract
and actually there is no studies have
investigated this plant
in term of synthesized nano zinc oxide
nanoparticles
now let's see how we made it
as you see this slide shows how i made
the green synthesis
of zinc oxide nanoparticles the method
was optimized to obtain the best result
because
we first used a coffee machine but did
not work
and then i boiled the blend sleeve to
get the extract from them
so also i adjust the pH to make it like
a
mild um 6.5-7
and all the nanoparticles
if you want more detail about the
methods you can read my final thesis
please
so the synthesizing side nanoparticles
was
analyzed by using uv visible
spectrophotometers
to confirm the synthesis of sync
of nanoparticles then the scanning
electronic microscopy
was used to measure the size and
identify the shape of nanoparticles
and finally uh antibacterial activity
was evaluated by using
will diffusion methods in
this one
and uh spot plate method
we just um in the well diffusion we
make a hole in the agar
while in the spot blade we just uh drop
uh of the nanoparticles in the surface
of agar
so the result tell us that the uv
visa spectrum photometer confirmed that
the zinc oxide nano vertical
successfully synthesized by using
Tasmania lanceolata
and the kunzea ambigua leaf extract you
can see the difference be
the different observation between the
control um
zinc oxide nanoparticles and green
synthesized
uh nanoparticles kunzea ambiguous here
and um testimonials
the bottom you can see it's a clear
observation so the
scanning electronic
microscopy shows that the control
zinc oxide nanoparticles were uh were
flat in the shape
uh this one actually represents the um
best
representative of the flat shape and the
average size actually
um was 220
nanometer while in uh kunzea uh while in
the ambigua and tasmanian lanceolata
nanoparticles
were multi-form shape and the average
size was
120 to 170 nanometer
now let's move to the antibacterial
activity of the nano particles by
world refugee method and spot plate
methods
you can see clear clear large zone of
inhibition uh especially against
B. cereus-S
um in the in both methods here spot
well diffusion and here in the bottom
uh spot blade method
and this is the zone of inhibition
uh i'll tell you from stress a4 as a
representer
actually in well diffusion we bought in
each well
a hundred micro mil with the
concentration of nanoparticles 15 micro
uh microgram per 0.1 milligram
millilitre uh and spot plate actually
just
only 10 micro mil with the same
concentration
so yeah this graph shows the mean
of zones of inhibition of well diffusion
methods
the green synthesized zinc oxide
nanoparticles show
zones of inhibition against all tested
bacteria
uh and the highest mean zones of
inhibition were uh were against A. finisterrensis
strains sorry
uh yes uh and uh where is the
uh especially um the a4
where in the lowest lowest zone of
inhibition was
against e coli
actually these this one is the
nanoparticles
and this was the control this one to uh
the green one and the
blue one is the extra plant extract
we will talk that in the next uh slide
the green synthesized into side nano
particles in the spot plates
methods also uh shows a high mean zone
of inhibition
against the finisterrensis strains
but a9
and the lowest zone uh mean zone of
inhibition
were against um B. cereus
you can see uh the plant structure shows
zone of inhibition against
only uh finisterrensis strains in both
methods
you can see here while uh
whereas in the e coli and B. cereus there
is no zone of inhibition
from the plant extract in both methods
um also there is no significant
differences between the mean of zones
of inhibition
of Tasmania lance nanoparticles and
kunzea ambiguous nanoparticles
antibacterial activities
in both methods you can see it here and
also in world diffusion there is no
differences
now let's discuss our result the methods
of synthesizing green synthesize um
a green as uh sorry uh synthesizing
green nanoparticles uh zinc oxide
nanoparticles was
modified to obtain green synthesized
that might hold high antibacterial
properties
by using a low temperature 40 celsius
particularly in the drying the
nanoparticles to maintain the integrity
of biochemicals that were
extracted from their plant leaves
however
other studies have used a high
temperature
which might affect on the active
chemicals
biosynthesizing zinc oxide nanoparticles
using
Tasmania lance and the kunzea ambiguous
uh inhibited all tested bacteria greater
than zinc oxide nanoparticles control
and plant extract we found that the
A. finisterrensis strain were
more sensitive for
synthesizing zinc oxide nanoparticles
than the
plant extract this might because these
marine bacteria
have different growth require
requirement
um for example absolute requirement for
sea salt
that might help enhance the effect of
nanoparticles
um whereas it is not important for the
e coli and bacillus uh bacillus serious
uh nanoparticles might be used as an
alternative to
antibiotic uh
alternative to antibiotic by adding the
nanoparticles for example in this
uh in fish feed as additives
as uh these bacteria multi drugs very
very uh multi-drug resistant
the bacteria may be established
resistant against the plant extract
but it is hard to resist
the green synthesized nanoparticles
so let's conclude our um
uh the conclusion in the conclusion
nanoparticles
is emerging as a new area of research
worldwide
and nanoparticles um can be used
in many applications such as a food
packaging and food
additives and food feed additives and
food preservatives
it's clear that different bacteria have
had a different response against
nanoparticles
and more significantly at finisterrensis
strain were sensitive to all nanoparticles
as a way to counter antibiotic resistant
nanoparticles can be potentially
act as a antimicrobial activity
sorry future studies need to be
test more plants to find better green
synthesis nanoparticles
also more research need to be done
in order to replace antibiotic
antibiotic usage especially in relation
to toxicity
and finally i would like to thanks my
supervisors
bro uh John Bowman and Sandra Garland
uh also i want to extend my thanks to
Shane Powell
my coordinator also the thanks
thanks for Zach, Caroline, Faisal and Cameron. thank you so much for your
listening
