Food Standards Australia New Zealand

Food Standards Australia New Zealand
1. Introduction
Food is vital for all living organisms to nourish and carry out the daily metabolism required for their
survival. Besides that, consuming food free from pathogens is further more important to protect
ourselves from unwanted diseases. Food micro biology enables us to analyse ,detect and counter the
microbial activity in food.Changes in the lifestyle have increased the demand of ready to eat or
minimally processed foods by people ,thus microbilogical safety of such foods is an utmost concern
to mainatin public health(Abadias et al. 2008).In Australia 'FOOD STANDARDS AUSTRALIA
NEW ZEALAND' (FSANZ) had regulated the guidelines for food safety. Salmonella ,Listeria
monocytogens,Staphylococcus aureus,Bacillus cereus,Aeromonas ... Show more content on
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2006),low concentration of ozone has been reported to be successful for inactivation of microflora
to enhance safety of fresh food(Kim, Yousef & Dave 1999).
3.Materials and Methods
The materials and methodology was followed as per the guidelines given in the lab
manual(Ajlouni,2015).
3.1 Week 1
In sterile conditions, 25 grams of sprouts were added to 225 ml of 0.1% peptone. with the help of
Stomacher, those two are blended to have a primary dilution of the sample. It acts as the 10–1
dilution, and then aseptically a serial dilution is done upto 10–5 . 100µl of sample from 10–3, 10–4,
10–5 were spread /inoculated on PCA agars. Half of the PCA plates are incubated aerobically , while
other half of them are incubated anaerobically. A negative and positive control is prepared by
inoculating 0.1%peptone and Escherichia coli onto PCA agar plates respectively.(incubation). Then
four different selective media were taken namely MacConkey, Bright Green Agar(BGA), Listeria
Selective Media(LSM), Oxytetracyclne–Glucose Yeast Extract(OGYE).these selective media were
inoculated by spreading the sample from 10–2,10–3,10–5 dilutions. (incubation).
3.2 Week 2
Agar plates which were incubated on previous week are collected. Total number of colonies on both
PCA and selective
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Lab Report Identifying Unknown Bacteria
Introduction:
Having a hands–on academic experience of the different techniques for instance aseptic technique
and procedures like gram staining is important characteristics for understanding the concept of
learning to identify a type of bacteria. During this lab report each student would be using a variety
of lab techniques and process/procedures from the lab course taught from the professor and learned
from students this semester. To include, by performing the multiple test with three types of medias
the students should be able to administer the methods to identify the unknown bacteria. With the
information from results and extra notes assist the students to identifying the unknown bacteria.
Lastly the benefits from this type of hands–on ... Show more content on Helpwriting.net ...
From the results of the first media student should choose a different media that could give a result
easy to determine any decolorization or change to media. Next choice of media was Triple Sugar
Iron Agar in a test tubes. The procedure is performed by taking a sterile needle and stabbing the butt
of the agar, then streaking the slant of the agar with a fish tale pattern all the way up and out. After
the test tube is incubated up to twenty–four hours the test tube is observed.
The last and final test of media is the citrate utilization test. The method of inoculation for this test is
taking a sterile needle and streaking the slant of agar with a fish tale pattern from the bottom to the
top. Later once the citrate test tube is incubated over night the agar can be looked at for results.
Results
Bloody Red with a Swiss (Carter 2017)
The decolorization around the colonies is an olive greenish color which results to be alpha
hemolysis Sunnyside at TSI (Carter 2017)
As seen above the entire agar is yellow top and butt. The Dirty Ocean (Carter 2017)
For the result of the citrate test if the agar changed to a royal blue it would be considered positive,
but it stayed green which results as

Unknown Bacteria: Microbiology Lab Report
UNKNOW BACTERIA LAB REPORT
UNKNOWN 36
Introduction
The purpose of this lab was to identify two unknown bacteria from a mixed culture. The reason for
identification of unknown bacteria was to help students recognize different bacteria through
different biochemical tests and characteristics. This is important in the medical field because
identification of unknown bacteria can help treat a patient by knowing the contributing source of a
disease. Also knowledge of different bacteria helped others make antibiotics used today. This lab
was completed by using the methods learned thus far in identification of bacteria.
Materials and Methods
A mixed culture of two unknown bacteria was provided by the instructor. The methods used for ...
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The colonies were smooth, translucent, and had a white brownish color. The Gram stain resulted in
Gram positive cocci. After the Gram stain was completed, the bacteria were streaked on a Mannitol–
Salt Agar plate and a Catalase test was performed. After these test were completed a Phenol Red
Dextrose Fermentation tube was inoculated, and a SIM Tube inoculated.
The Unknown Bacteria 36/Bacteria # 2 on a TSA plate was examined by the naked eye and under a
dissecting microscope. Bacteria # 2 was approximately 3 – 4 mm in diameter. They were circular in
form with an entire margin and a flat elevation. The colonies were rough (granular), translucent, and
white brownish color with black granules. The Gram stain resulted in a Gram negative rod. After the
Gram stain was completed, the bacteria were streaked on an Eosin –Methylene Blue Agar plate and
an Enterotube II was inoculated.
See Table 1 and Flow Chart 1 for results of Bacteria # 1 and Table 2 and Flow Chart 2 for results of
Bacteria # 2.
Table 1: Biochemical Test Results (Bacteria # 1) TEST | PURPOSE | REAGENTS |
OBSERVATIONS | RESULTS | Gram Stain | To determine the Gram reaction of Bacteria #1 |
Crystal violet, Iodine, Alcohol, Safranin | Purple cocci | Gram positive cocci | MSAAgar plate | To
determine Gram positive Staphylococcus species | None | Yellow halo around streak |

Identifying The Unknown Microorganism Given By The Instructor
Unknown #2 Lab Report
Danielle Gudino
BIO 211L
Section 6
11/20/2014
Introduction
This experiment was about identifying the unknown microorganism given by the instructor. This
exercise is important to understand and apply all previous laboratory practices, as well as those
learned in our first unknown exercise, for identifying the given unknown organism. With the
knowledge and practice of performing biochemical and physiological identifying tests, I was able to
determine the unknown bacteria. For this experiment, I was given Unknown #12 and used a series of
tests to determine the specimen, further explained in this report.
Materials and Methods
For the Gram stain, I used a microscope slide, wash bottle of water, clothespin, and the reagents
crystal violet, Gram's iodine, ethyl alcohol, and safranin to observe whether the organism was Gram
negative or positve. The method was placing and heat fixing a loopful of the unknown organism on
the slide. The organisms were then stained with crystal violet for a minute, rinsed off, flooded with
iodine for a minute, rinsed off, decolorized with alcohol for 30 seconds, and then finally stained with
the counter–stain, safranin, for a minute. I streaked the unknown onto a TSA plate and incubated at
35 C. With a pure colony, we performed a second gram stain procedure and inoculated it into a TSA
slant. I used BCP Lactose broth and a loop to perform a BCP Lactose test. The broth was inoculated
with a loopful of the unknown and incubated

Degradation Of A Wide Range Of Model Pollutants
ABSTRACT Heterogeneous photocatalysis, has been reported to be effective for the degradation of
a wide range of model pollutants in suspension. The use of nanostructured materials is one approach
to improving photocatalytic efficiency. Therefore, this work is based on the use of nanomaterials
such as titania and silver–zinc oxide photocatalysts to degrade amoxicillin trihydrate (a model
antibiotic pollutant) in suspension under UV–C irradiation and compares the efficiencies of the
photocatalysts in degrading model pollutant used in the study. The Silver decorated Zinc oxide
Nanoparticles were prepared in–house by hydrothermal synthesis that yielded nanospheres. The
nanomaterial was characterized using XRD and UV Visible spectroscopy. A significant and faster
degradation of amoxicillin has been observed with Degussa P25when compared with in–house
synthesized titania and Ag–ZnOphotocatalysts. Introduction Pharmaceuticals constitute an emerging
class of micropollutants, that occur in the environment due to point sources, like production
effluents and waste disposal, as well as diffuse sources, like run–off from fields and anthropogenic
effluents.The presence of pharmaceutical compounds such as antibiotics in the ecosystem exists
from almost 30 years before. But, in mid–1990s, when the use of such antibiotics increased at
alarming concentration and their presence became a thing of concern, at this point of time many new
analytical technologies were developed.

Proteus Vulgaris Microbiology
Proteus vulgaris #12
The importance of identification of a certain microorganisms can range between a life threatening
diseases to a creation of certain antibiotic. Understanding the principals of living microbes and
identifying my unknown bacteria through numerous biochemical and metabolism tests, with the
outmost confidence, Proteus vulgaris had the precise qualifications. The point of this report is to
further explore the identification of my unknown bacteria by revealing the results of the experiments
and comparing them to the other six known bacteria: Micrococcus luteus, Staphylococcus aureus,
Staphylococcus epidermidis, Alcaligenes faecalis, Escherichia coli, and Proteus vulgaris that were
used in the lab, as well as comparing and ... Show more content on Helpwriting.net ...
(Harley, 2011, pp. 102–103) Sucrose and lactose serve as a fermentable carbohydrate sources which
promote its growth of fecal forms and provide color change differentiation. (Harley, 2011, p. 104)
Therefore, if E. coli is being platted on the EMB, after plate's incubation period, it should produce a
green metallic sheen on the agar due to the bacteria being a strong fermenter. My unknown bacteria
tested positive for growth, and agar was fermented reddish burgundy in color. Subsequently, the
unknown bacteria was later inoculated with a sterilized loop into the liquid tryptic soy broth and
incubated at an appropriate temperature. Its results were used for proper identification of turbidity,
spots and flocculation. (BD™ Tryptic Soy Broth (TSB), 2008) The results of the unknown were
cloudiness and some settlement on the bottom of the tryptic soy liquid. The next step was conducted
to find out if all the bacteria, as well as the unknown culture, required oxygen for growth, varying
from an aerobic environment, where bacteria needs oxygen to grow, to facultative anaerobic
environment, where bacteria will grow either with or without oxygen but better in its presence. All
the bacteria, along with the unknown, were separately inoculated and tested. My unknown culture
results tested positive for growth in facultative anaerobic environment. In the next sequence of lab
experiments, the results of unknown bacteria were determined by glucose fermentation,

Essay about Microbiology Unknown Bacteria
INTRODUCTIONS:
Microorganisms are both beneficial and harmful. These microorganisms are important to humans
because they play a role in the ecology of life, by decomposing wastes, both natural and man–made,
such as creating nitrogen fertilizer at the root zones of certain crops. Other several pathogens that
can cause serious harm, even immediate death due to the diseases or disease causing products they
produce. Overall, microorganisms play an important role in life.
The purpose of this study was to identify the unknown bacterium using biochemical tests and
various methods that had been learned from previous the microbiology laboratory class. Identifying
the unknown bacterium was determined by separating and differentiating possible ... Show more
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Then the following differential tests were performed:
Gram Stain Test:
Two smears of the unknown bacterium #5 were inoculated while the second smear was used for a
back up. The unknown bacterium dried for at least forty minutes. After the smears dried, the slides
were heat fixed two times to ensure the stability of the organism. The slide was placed on top of the
staining rack then over the small sink.
The drops of crystal violets, approximately 15 drops, were flooded until the smear were all covered
and then allowing resting for one to two minutes. After two minutes, the slide was titled over the
sink and washed off, with the distilled water bottle, by aiming the stream of water above the smear.
The specimen appeared blue–violet when observed with the naked eye. The drops of Gram's iodine
were applied on the slide until covered and then allowed to react for one minute or more. After the
time elapsed, the slide was rinsed again with distilled water following immediate drops of Gram
stain decolorizer added one drop at a time.
Again, after ten seconds, the slide was rinsed with distilled water to wash off the decolorizer. The
slide was placed back on the staining rack. Approximately ten drops of safranin were covered on the
slide allowing resting for one minute. After one minute, the slide was rinsed one final time on the
small sink followed by blotting the stained slide with Bibulous paper. The slide was placed between
pages of Bibulous paper to help

The Isolation And Identification Of An Unknown Bacteria
Sam Afflu
Section H1
Microbiology 680 390
Lab Report 2: The Isolation and Identification of an Unknown Bacteria
Abstract
This laboratory experiment's objective was to take a pure culture and isolate it from a mixed culture.
The other part of the objective was to ascertain what species of bacteria that the pure culture was.
The hypothesis made stated that so long as lab protocol was followed, the unidentified culture would
be positively recognized/identified. An isolated pure colony of the unknown culture was obtained
using the quadrant streak plate method. Afterward, the culture was Gram stained, and the results
showed that it was Gram positive. Motility tests were done on the unknown using a filter paper
bridge on a petri dish that contained TTC with agar. The unknown was revealed to not be motile,
which meant that it did not possess flagella. The last test done was to learn the metabolic capabilities
of the unknown bacteria. There were tests done for citrate utilization, the mixed fermentation
pathway, catalase presence, carbohydrate fermentation in mannitol, lactose and glucose, urease
production and the butanediol fermentation pathway in order to better identify the unknown
bacteria. The results from each of the metabolic tests in conjunction with the motility and Gram
staining tests were ultimately compared to results from database containing many different kinds of
results from various bacteria. The unknown from the mixed culture was identified as
Staphylococcus

Lab Report : The Gram Stain
Lab Report 1–The Gram Stain
Eric Zuberi
Lab section 1
February 8, 2015
This report represents my individual effort. I did not receive or offer aid to anyone when performing
this assignment, nor did I plagiarize any material.
Signed: _____________________________________________ Eric Zuberi I. Introduction
In all areas of biology, it is easy to see that structure is related to function. This statement holds true
in microbiology as well, the study of microorganisms, including bacteria. One characterizing feature
of bacteria is the cell wall, which can generally (although not in all situations) be categorized into
one of two categories: either Gram positive or Gram negative. Gram positive bacteria's cell walls are
composed of a large peptidoglycan layer (up to 90% of their cell wall). Within this large
peptidoglycan layer, one can find techoic acids, which contribute to the maintenance of cell wall
structure, and lipotechoic acids, which attach to membrane lipids. Gram positive bacteria that act as
pathogens can also potentially release exotoxins, which can have very dangerous effects on humans.
Gram negative bacteria, on the other hand, have a very small layer of peptidoglycan in their cell
wall, which is surrounded by an outer membrane. Within the outer membrane, one can find the
lipopolysaccharide layer, which is one of the most distinguishing factors of Gram–negative bacteria.
It is important to note that Gram negative bacteria fail to possess techoic

Essay on Microbiology Lab Report
Lab Report #1: Observing Bacteria Microbiology
Abstract:
This lab exercise familiarized the student with the use of a microscope by observing and identifying
various different slides under the microscope. The student practiced observing the given slides under
the 10x, 40x, and 100x (oil immersion) objective lenses, which allowed for the identification of the
different organism's shapes and sizes.
Purpose:
The aim of this exercise is to equip the student with the knowledge and skill necessary for
conducting microscopic observations. It is also intended to teach the student the various sizes and
shapes of several different types of bacteria.
Procedure:
1. Focus the microscope on a slide containing ... Show more content on Helpwriting.net ...
Bacteria spirillum – under 40x magnification
Bacteria spirillum – under 100x magnification
* Bacteria coccus.
Under 40x magnification: loads of purple round cells.
Under 100x magnification: paired round purple cells.
Bacteria coccus – under 40x magnification
Bacteria coccus – under 100x magnification
* Bacteria Bacillus.
Under 40x magnification: a view of many pink organisms shaped like rods.
Under 100x magnification: an identical view as the 40x magnification.
Bacteria bacillus – under 40x magnification

Bacteria bacillus – under 100x magnification
4. The microscope was focused on the yoghurt prepared and fresh yoghurt slides and the results
were as follows.
* Yoghurt prepared.
Under 40x magnification – a view of purple bacteria whose shape is difficult to make out.
Under 100x magnification – a view of purple rod shaped bacteria/bacilli; some appear as either
single rods or paired rods (diplobacillus).
Yoghurt prepared – under 40x magnification
Yoghurt prepared – under 100x magnification
* Fresh yoghurt.
Under 40x magnification – a view of loads of bacteria moving about with undefined shapes.
Under 100x magnification – an indistinct view of loads of varied bacteria moving about, such as
diplococci, streptococci, staphylococci, diplobacillus, and streptobacillus.
Fresh yoghurt – under 40x magnification
Fresh yoghurt – under

Microbiology Unknown Report
During a lab in my Microbiology class, we got the chance to do what is called an Unknown Report.
It is a report of an unknown sample of bacterial that we performed different tests on to identify the
bacterial species. By following the imporatant steps of aseptic technique in all tests, we were able to
identify the unknown bacteria. These tests involved different petri dish agars, broths, and slants to
know what kind of bacteria we had. As a result, we identified our bacteria as an Escherichia coli.
Each tests gave us an important characteristics of our bacteria that helped us to identify it.
The most imporatant test that we performed was the Gram stain. Gram stain test's meaning is to
differentiate between Gram positive and Gram negative bacteria ... Show more content on
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Therefore, the purpose of this test to identify bacteria based on these features. As a result, we had
white, slime, a little shiny colonies that was shaped as almost a flower.
In addition, we were able to know if the bacteria was positive or negative for the catalase reaction.
Catalase reaction is done by adding hydrogen peroxide–H2O2. If the test was positive, then the
colonies would start forming bubbles, and if it's negative, then it won't. Therefore, in our sample of
the bacteria was a positive catalase reaction because we saw bubbles coming out after adding the
hydrogen peroxide.
Then, we used different agars whether there were selective or differential or even both to gives us
more information about the unknown. One of the most imporatant agar that we used was Mannitol
salt agar, which is both selective and differential medium. Mannitol salt agar is selective for
halophiles and differential for mannitol use. It starts as a pink agar that changes color to yellow or
orange if the bacteria was able to grew on this salty culture and was able to use mannitol as a sugar.
However, our bacteria sample didn't even grew on it; therefore, it didn't change agar color and
stayed

Danish Physician Hans Christian Gram Stain, Escherichia...
Gram Staining: Micrococcus leteus, Escherichia coli, and Unknown Colony
Ethan Hinkle
Microbiology Lab 3051, Section 001
Instructor: Harrison Taylor
February 9, 2015
This report represents my individual effort. I did not receive or offer aid to anyone when performing
this assignment, nor did I plagiarize any material. Signed:
__________________________________________________________
INTRODUCTION
In 1884, Danish Physician Hans Christian Gram was in the process of developing a staining
procedure that would potentially differentiate prokaryotic (mainly bacterial cells) and eukaryotic
nuclei in tissue samples. However, Gram was not effective in developing the differential tissue stain,
his derived work would serve as the most valuable differential stain in bacteriology, the Gram–stain
(1). Moreover, it soon became clear that most bacteria could be catorgorized into two major groups
based upon their response to the Gram–staining procedure. Gram–positive bacteria stained purple,
whereas Gram–negative bacteria stained a pink–red (2).
Complete structures of Gram–positive and Gram–negative cells were not differentiable until the
development of the transmission electron microscope. Gram–positive bacteria comprise of a
singular, 20–80nm thick homogenous layer of peptidoglycan just outside the plasma membrane. In
comparison, Gram–negative have two apparent layers: a 2–7nm thick peptidoglycan layer incased in
a 7–8nm thick outer membrane. The most distinct

A Series Of Biochemical Tests
A series of biochemical tests were conducted in order to determine the identity of an unknown gram
negative bacterium. The unknown had the potential to be one of six different gram negative bacteria:
Escherichia coli, Pseudomonas aeruginosa, Enterobacter aerogenes, Proteus mirabilis, Klebsiella
pneumonia, or Salmonella typhirmurium. After using the T–streak method to isolate pure colonies
and confirming the gram negative nature of the unknown bacterium the unknown was subjected to
seven biochemical tests and the results compared to the results of the six known bacteria for the
same tests. After performing the Triple Sugar Iron Agar Test, Sulfur Indole Motility Test, Methyl
Red Test, Voges–Proskauer Test, Citrate Test, Urease Test, and Gelatin Test it was confirmed that
identity of Unknown #15 was Salmonella typhirmurium.
While all bacteria retain basic qualities identifying them as prokaryotes they do not function, grow,
or even metabolize in the same way. These differences distinguish bacterial species from one
another, like a thumb print identifies a single individual from every other person on earth. Testing
for these unique factors through a series of biochemical tests and staining techniques allows for an
unknown bacterial strain's "thumb print" to be generated. From there the unknown's thumb print can
be compared to the thumb print of known bacterial species allowing for identification.
The first step in identification is performing a Gram Stain. Due to the fact

Use of Maggots for Wound Care
Orthopaedic Surgery (2010), Volume 2, No. 3, 201–206
ORIGINAL ARTICLE
Clinical research on the bio–debridement effect of maggot therapy for treatment of chronically
infected lesions os4_87 201..206
Shou–yu Wang MD1, Jiang–ning Wang MD2, De–cheng Lv MD1, Yun–peng Diao PhD3, Zhen
Zhang MD1
1
Department of Orthopedic Surgery, The First Afﬁliated Hospital, 3Department of Pharmacy, Dalian
Medical University, and 2Institute of Reconstructive Surgery, Dalian University, Dalian, China
Objective: To evaluate the bio–debridement effect of maggot therapy for treating chronically
infected lesions. Methods: A retrospective study was conducted of 25 patients with diabetic foot
ulcers and 18 patients with pressure ulcers after spinal ... Show more content on Helpwriting.net ...
The patients who were agreeable to maggot therapy were required to sign an informed consent form.
Preparation of maggots
Firstly, eggs were collected from the eyes of Scomberomorus niphonius and disinfected in 1%
sodium sulﬁte solution for 3 min, and subsequently in 3% Lysol brand disinfectant for 5 min. The
disinfected eggs were then transferred to sterile vials to clone. Secondly, third stage larvae of Lucilia
sericata were selected to be placed in 3.5% formalin for 5 min, 2% hydrogen peroxide solution for 3
min, and then 5% dilute hydrochloric acid solution for 5 min. After the two–step disinfection, the
larvae remined vigorous. A hundred randomly selected larvae were proven to be aseptic by bacterial
culture test.
Treatment
After two–step disinfection, disinfected larvae were applied to the lesion.

Microbiology 150 Lab 3-Selective vs. Differential Media
Online BIO 150 Introductory Microbiology #3 Lab Report
NAME __ Lab Group 2_____
Answer the following questions as you work your way through the lab material typing in your
answers. Then submit your finished lab report as a Microsoft Word document. This lab report is
worth 100 points towards your final lab grade. Each Q is worth 2 points unless otherwise noted.
Also, per the Honor Code, this work must be your own. This is due Mon. 10/8 at 11:59 PM. The
theme of this lab is the identification of unknown bacteria and viruses in a lab.
Selective vs. Differential Media
Selective vs. Differential Media
Use the following website to help you answer Q 1 and 2 ... Show more content on Helpwriting.net ...
The Alcohol in the agar interferes with the DNA synthesis of Gram–negative organisms which
inhibits growth.
ATLAS SECTION 7: DIFFERENTIAL MEDIA
Please read over this section. Differential media usually distinguish or differentiate different species
of bacteria based on the color of the individual colonies or the areas surrounding them.
Look up these tests and answer the following questions: Blood Agar, Catalase, Citrate, Coagulase,
Indole, Methyl Red, Motility, TSI, Urea,
11. What is a hemolysis and what type of bacteria produce it? (2 pts.)
Hemolysis is the exotoxin of gram positive cocci (streptococcus, enterocus, and aerocccus) that
destroy RBCs and hemoglobin.
12. What are the 3 major types of hemolysis and their descriptions? (2 pts.)
The three types of hemolysis are B, A, Y. B is complete clearing or destruction of the RBCs or
hemoglobin and it results in a clearing of the medium around the colonies. A is partial destruction
and a green color forms around the colonies. Y is non–Hemolysis and shows simple growth and no
change to the medium.
13. When would you use the Catalase test? (2 pts.)
This test should be used when trying to identify organisms that produce catalase. It is used when
differentiating between Catalase positive micrococcaceae and catalase negative streptococcaceae

and some variations of the catalase test are for mycobacterium.
14. The Citrate Tests is part of what test series?

How Gram Staining Is Negative Or Positive, It 's...
Purpose:
The purpose of this lab was to be able to gram stain given cultures and examine their reaction to
certain dyes and determine whether the culture is negative or positive, it's morphology, and
arrangement of the cells. By using the Gram staining method, microorganisms can be narrowed
down for the identification process as well as the leading to diagnosis
Procedure:
For this experiment, we were given three gram staining slides as well as a petri dish with five
different types of incubated microorganisms that were divided. The five different organisms on the
petri dish being observed were Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa,
Klebsiella pneumonia, and yeast known as Candida albicans. On the surface of the ... Show more
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On the third slide, the smear was not taken from the petri dish, however it was taken from a
thorough swab of the mouth and smeared within the given margins on the slide. The samples were
then left to air dry. Once the slides dried, they were passed through a flame 4–5 times to follow the
aseptic technique protocols.
Once this was done, our next step was to begin the Gram staining process. First, is the Primary stain,
using the crystal violet dye color. The slides were all laid out on top of a rack placed over the sink
station and were flooded with the violet dye color; the slides were left with the dye on them for 1–2
minutes to assure they were stained. The slides were then rinsed off thoroughly. Next, the slides
were stained with the Mordant (fixative) Iodine Gram stain which appears brown in color. The slides
were then flooded with the brown dye for 1–2 minutes and then rinsed off.
After all the slides were stained accordingly, they needed to be decolorized with 95% ethyl alcohol
which is clear in color, and will be the determining factor between whether the stains are negative or
positive. Just as we did with the crystal violet dye and the brown iodine dye, the slides were
drowned with the 95% ethyl alcohol. The difference here was how long to leave the alcohol on each
depending on how thick the samples were. The slides labeled "mouth" were removed within 20
seconds. The rest of the samples were removed within the following 10 seconds.
Lastly, to complete

Unknown Lab Report
Thomas Goss Microbiology for Health Sciences Dr. Wiles 10/17/14 Unknown #44 Lab Report
Bacteria are ubiquitous; they can be found on the skin, in the soil, and inside the body. Because of
the very nature of this ubiquity, it is important to be able to determine between different strains of
bacteria. An example of this is determining the causative agent for a disease so that the patient will
be treated with the appropriate antibiotics. It may be important to determine the bacteria in a certain
region, because like with enteric bacteria, it is normal to find them in the digestive tract as they are
in a symbiotic relationship with our bodies in this area; however, they also cause opportunistic
infections in places outside of the digestive tract to our detriment, such as with a urinary tract
infection. Some strains of bacteria are common to nosocomial infections, and identifying these
bacteria as such helps create the guidelines for healthcare workers in antiseptic technique. All of the
morphology and characteristics of each strain of bacteria help us to better understand the role of
bacteria in the body as well as helps us understand how they can cause illness, and what treatment
regimen to set in place. In lab this semester, a sample of unknown ... Show more content on
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To perform this test, a tube of broth rich with glucose is acquired. In this tube is phenol red, a pH
indicator. Initially, the tube appeared pink in color, indicating a normal pH level. Next, a sample of
unknown #44 is introduced into this medium using the aseptic technique, and this is allowed to sit
for several days. If the organism is able to ferment glucose, the pH in the medium would decrease
and cause the phenol red to exhibit a yellow color. In addition to the straw color, gas can also be
produced and trapped inside the Durham tube placed in the medium. This production of acid and gas
is a direct result of the fermentation of glucose, as seen with unknown

Unknown Lab Report
Identifying Organism 6C Introduction: This report details the steps taken and processes used to
discover the identity of the unknown organism given to me on Tuesday, November 28th, 2017. With
all of the knowledge and skills gained over the semester, in class and in lab, I was able to positively
identify my unknown organism. The objective of these labs being, that I successfully utilize the tests
and procedures taught during the course to correctly identify my organism and to be able to explain
the reasoning behind my tests and results. This report will go in depth with the tests used, results
yielded, and rationale behind each. Procedures: On the first day of the lab, I was presented with an
unknown bacteria labeled simply as 6C. I first observed ... Show more content on Helpwriting.net ...
I was able to do this through various tests starting with a gram stain. When observing my organism
under the oil immersion lens I noted some important characteristics. For one, my organism was
gram negative. This I knew due to the fact that my organism was pink under the microscope. This
meant it was unable to hold the crystal violet stain due to its thinner peptidoglycan layer, marking it
as a gram negative organism. This informed me as to what tests to perform next. The next test was
for lactose fermentation. I accomplished this by streaking my bacteria on a MAC plate. Pink
colonies on a MAC plate would indicate that the bacteria growing on that plate could ferment
lactose, this in addition to the fact that it would inhibit the growth of gram positive organisms made
the MAC plate differential and selective, as well as perfect for assisting me in identifying my
organism. The results of this test were negative on account of the fact that no pink bacterial colonies
were produced, indicating that they were unable to ferment lactose. If the bacteria had been able to
ferment lactose there would have been a drop in pH that would have triggered the neutral red in the
agar, making the colonies pink. From these results, I was determine which three tests to perform in
order to deduce the identity of my bacteria. I chose the ornithine decarboxylase, the indole
production, and the urease hydrolysis tests to give me the identity of my bacteria. I chose the
ornithine decarboxylase test to see if my organism could utilize ornithine. This would be indicated
by a pH change in the medium, in this case the MIO medium. When the organism used up the
glucose present in the medium the pH would drop causing it to turn yellow. If it could utilize
ornithine, the pH would rise back up and the medium would return to its original purple coloring.
My ornithine decarboxylase

Local Alignment Search Tool
Basic Local Alignment Search Tool (BLAST)
The Basic Local Alignment Search Tool (BLAST) was the final portion of this lab report. BLAST is
provided courtesy of the National Center for Biotechnology Information (NCBI). After running the
five chosen tests, students were given the two 16S rRNA sequences that were associated with their
assigned culture. The BLAST results served to confirm or disprove the hypothesis of what the
unknown may be. The BLAST program compared the given 16S rRNA sequence to a database of
known sequences and searched for similarity. (10) This search tool is capable of comparing
nucleotide or protein sequences to find statistical significance between the matches. A perfect match
to the unknown sequence is indicated by a ... Show more content on Helpwriting.net ...
After appropriate incubation, sulfanilic acid (reagent A) and dimethyl–α–napthylamine (reagent B)
were both added to the test tube. A color change should have been observed after approximately one
minute if the unknown was positive for nitrate reduction (1). However, no color change was present
which indicated no nitrate reduction. As a confirmation test, powdered zin was added to the tube.
There was an immediate color change to red after the addition of zinc. The color change from zinc
indicated that there were still intact nitrates within the broth, thus, no reduction had occurred. The
positive control for nitrate reduction was E. coli which changed to a red color after the addition of
reagents A and B. The negative control was M. luteus which had

Taking a Look at Bacterial Gastroenteritis
Bacterial gastroenteritis, a case report– 5
Gastroenteritis is an illness due to the inflammation and infection of the digestive system, where
symptoms are characterised by abdominal pain and cramps, vomiting, diarrhoea, nausea, bloating
and in some cases blood and pus present in stools (Department of Health, Victoria 2012). The
pathogens responsible for gastroenteritis are bacteria, viruses, protozoa, yeast and fungi. Bacterial
gastroenteritis can be caused by ingestion of pathogens or their toxins. The most frequently isolated
pathogens in gastroenteritis are Campylobacter jejuni, Staphylococcus, E. coli, Yersinia, Salmonella,
and Shigella etc (Vorvick LJ et al. 2011).
Bacterial gastroenteritis can occur to a person or a group of people that all ate the same
contaminated foods. Often this kind of outbreaks occurs after eating at restaurants, large social
functions, cafeterias, or picnics. The contaminated food with pathogens or their toxins can occur by
not appropriately following food safety protocols used in food preparation and handling at homes,
restaurant and grocery stores (Department of Health, Victoria 2012). Food prepared with
contaminated egg products, raw eggs and undercooked poultry meat and pork were found as the
primary sources of Salmonellosis (Wattiau P et al.2011).
Salmonellosis is the most frequently occurring gastroenteritis caused by Salmonella species, which
is Gram negative, short plump shaped bacilli, non–sporing, non–capsulated, aerobic and

Gram Negative Unknown Lab Report
Gram Negative Unknown Lab Report
April Smith
August 1, 2014
Unknown 20
Abstract
The bases of this experiment was to discover the identify of the unknown from three possible
specimens: Klebsiella pneumonia, Escherichia coli, and Enterobacter aerogenes. Utilizaing the T
streak technique, the bacteria was isolated into pure colonies for further study. The Gram Stain
method was used to identity the morhphology of the bacteria such as the shape and whether the
bacteria was Gram positive or Gram negative. Biochemical test were also used to help identify the
unknown bacteria. The biochemical test used was the Triple Sugar Iron Agar, Sulfur Indole Motility
test, Methyl Red test, Voges–Proskauer test, Citrate test, Urease test, and the Gelatin test. After
observing the morphology of the bacteria using the Gram Stain method and utilizing all the possible
biochemical test, the bacteria was identified to be Enterobacter aerogenes.
Introduction
Gram negative and gram positive bacteria differ from each other in many ways especially in the
composition and size of their cell walls. Unlike Gram–positive bacteria, Gram–negative bacteria
have a thin peptidoglycan layer surround by an outer membrane. This outer membrane contains
many proteins one of them being lipopolysaccharides (LPS), which contributes to the bacteria's
negative charge. One part of this protein is a lipid, called Lipid A, which is considered an endotoxin
because this lipid triggers an immune response stimulating fever

Phage Lab Report
Isolating and characterize a novel phage from the environment requires several steps and several
frustrations. By isolating and investigating a phage found in the Pullman region can hopefully lead
to a newly discovered phage that can help researchers discover more about the life cycle and process
of phage infection. Some phage infection can be good due to infecting the bacteria that is not wanted
or is harmful to the environment or humans. Within this lab, there were steps taken necessary to
isolate a novel phage that was obtained from the surrounding Pullman area. This report reflects
plaques being isolated but then stopped due to errors and loss of plates. The final touches and
procedures were accomplished with a given DNA ladder that was ... Show more content on
Helpwriting.net ...
Next, aseptically add 20mL of T–soy broth and 2mL of late log phase of B. thuringiensis culture.
Incubate this flask for 24 hours at thirty degrees Celsius shaking at 180rpm. The next time in lab,
remove between 1 and 1.5 mL from the top of the tube that holds the soil using a syringe. Open a
package of .22μm filter and place the syringe in the top of the filter and dispense the liquid into a
centrifuge tube that is labeled as 100 and close the tube immediately. For the negative control,
dispense 1mL of SM buffer into a microcentrifuge tube labeled negative control using a syringe.
With four microcentrifuge tubes label them –1, –2, –3, and –4. Add 90 μL of SM to each tube, and
then add 10μL of the 100 tube to the –1 tube and vortex. Then add 10μL of the –1 tube to the –2
tube and vortex. Keep this process going till the –4 tube. Next, dispense 50μL of the undiluted
sample into .5 mL of B. thuringiensis and then vortex. Now mix in 5 mL of TA to the culture tube
and pour onto a plate labeled 100 and let solidify. On a different plate, draw a grid with sections
labeled negative control, –1, –2, –3, and –4. Aseptically add 4.5mL of TA with .5mL of B.
thuringiensis by pouring and then pour onto the plate evenly. Let the plate sit for about ten minutes.
After ten minutes transfer 5 μL of the negative control and the dilutions into the proper

The Uses Of Differential Stain
Erica Stevens June 2, 2015 Gram Stain Laboratory Report
Purpose:
To understand how the use of differential stains can help us identify cell morphology. Also to
identify the presence of two different bacteria in our mixed sample by identifying differences in
color, shape and grouping of eubacteria.
Theory and Background:
Gram stain is the most important and "commonly used differential stain in microbiology" (1).
Developed by Hans Christian Gram in 1884, while searching for a way to visualize bacteria in lung
tissue of people who had died from pneumonia. Gram used crystal violet as the primary stain, iodine
as the mordant followed by treatment with ethanol as a ... Show more content on Helpwriting.net ...
The cell membrane is a selectively permeable barrier composed of a phospholipid bilayer and
proteins. This layer of the cellular envelope, protects the cell from bursting under external osmotic
pressure and for communication between cells. The cell wall is found on the outer surface of the
cellular envelope, and it is here that the composition of the cell differs (4). In gram–positive cells,
the cell membrane is separated from the cell wall by a thin periplasmic space. The periplasmic space
is an area for storage of enzymes secreted by the cell membrane and synthesis of peptidoglycan (3).
The cell wall is composed of peptidoglycans; many long chains of glycans linked together by
peptides creating a permeable mesh–like surface. In gram–positive cells the layers of peptidoglycans
is very thick (20–80nm) and it protects the cell from bursting from internal pressure (3,4). The cell
wall also contains polysaccharides (teichoic acid and lipoteichoic acid) that are embedded in the
peptidoglycan structure. These structures assist in maintenance of the cell wall, cell division and
pathogenic functions of the cell (3). Gram–negative cells have a larger periplasmic space that
separates the cell membrane from the cell wall. This periplasmic membrane is the site for metabolic
reactions (3). The cell wall in gram–negative

Lab Report : An Unknown Microorganism Using Lab Techniques
Unknown Lab Report
Unknown #27
Rona Hakaj
12/08/2014
Dr. David Mwangi
Microbiology
Spring /2014
3305–04
Introduction: The purpose of this lab was to identify an unknown microorganism using lab
techniques. The importance of identifying microorganisms is essential to the survival of humans,
expansion of modern day medicine and improvement of quality of life. In 1884, Hans Christian
Gram designed a differential staining technique to identify bacteria that would change the future of
microbiology. He give rise to a staining process, known as the Gram stain to differentiate
microorganisms into two groups between positive and negative gram staining microorganisms. The
Gram stain is essential in a lab technique as it distinguishes the cells based on the physical
properties of the individual cell walls, and is almost always the first test preformed to differentiate a
microorganism. The identification of weather a microorganism is gram positive or negative can
revel the bacteria's virulence, cell wall structure, resistance to antibiotics, resistance to physical
disruptions and so much more. In order to identify the unknown provided, unknown #27, the Gram
stain was the first test preformed. After discovering that the unknown bacterium was indefinitely a
gram positive microorganism, the vast possibilities were narrowed down. However, In order to more
definitively identify the unknown, the next step was to preform biochemical tests. A biochemical test
identifies metabolic

How to Write a Lab Report in Microbiology
HOW TO WRITE AN UNKNOWN LAB REPORT IN MICROBIOLOGY GENERAL Unknown
reports in microbiology are written in scientific format. Scientific writing is written differently from
other types of writing. The results of the exercise or experiment are what are being showcased, not
the writing. The purpose of scientific writing is not to entertain, but to inform. The writing should be
simple and easy to understand. There is a specific style that must be followed when writing
scientific reports. Scientific writing is typically written in the passive voice. The pronouns "I", "We"
and "They" are not typically used.. For example, instead of writing "I used a TSA agar plate to
isolate my unknown," it is customary to write, "A trypticase ... Show more content on
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Note all of these tests were performed by the methods listed in the lab manual by De Mers (1). Table
1 lists the test, purpose, reagents and results. All of the following tests were performed on this
unknown: 1. Oxidase test 2. BCP Lactose 3. Indole 4. H2S 5. Citrate 6. Motility 7. Methyl Red 8.
Urea" Another way is to write out the methods in detail in either a paragraph form or listed. This
way is not necessary for this type of paper, since this is lab report for the identification of an
unknown bacterium and the methods are explained in detail in the lab manual. If there is a procedure
that the instructor added or made changes to, or the student used another procedure not in the course
lab manual, then it should be written out and referenced. See some of the examples of papers
identifying an unknown from the web sited below. RESULTS This is where the results are
summarized. The method results should be in a table format (see examples below). This is also
where the flow chart showing how you arrived at the answer is stated. A short paragraph explaining
how the results are presented can be included. Example: Unknown G had the following morphology
on a TSA plate: medium sized opaque cream colored colony. After determining that it was a Gram
negative rod, an oxidase test was performed and it was inoculated into a BCP lactose tube

Essay Lab Module 1
MBK – Lab Report Name: ____
Section: ___
Module 1, Experiment 1:
Observing Bacteria and Blood
(No microscope needed for this lab)
Questions:
A. List the following parts of the microscope, AND
Briefly describe the function of each part.
A. Eyepiece – transmits and magnifies the image from the objective lens to the eye.
B. Main tube – moves vertically for focusing
C. Nosepiece– holds the objective lenses and rotates them.
D. Objective lens – Objective lenses provide different focal lengths.
E. Stage – holds the object to be viewed
F. Diaphragm – controls the amount of light reaching the slide
G. Light source – a mirror, lamp, or bulb for illuminating slide work.
H. Course adjustment – used for the ... Show more content on Helpwriting.net ...
E. What are four primary bacterial shapes? Cocci, bacillus, spirillum, vibros
F. Bacteria occur in several common arrangements with each other. What are they?
They occur as single bacterium, which uses the names cocci, bacillus, spirillum, vibros. They occur
as pairs, which add the prefix diplo, such as diplococci. They appear as linked chains, with the
prefix strepto, as in streptobacillus, and they occur in clusters with the prefix staphlo, as an example,
staphylococci.
G. Can you identify specific bacterial morphologies on either the fresh or prepared yogurt slide? If
so, which types? Yes, there observable shapes in the slide that would seem to indicate the presence
of bacillus and cocci. The cocci appear to grow in clusters, which would indicate that they are
staphylococci, and there also indicates that streptococci chains are presented. As Lactobacillus
bulgaris and thermophillic Streptococcus are the most common types of bacteria in yogurt, one
could imagine that they are the specific bacteria present in the slide.

H. Observe the images of a blood smear. Describe the cells you were able to see in the blood smear.
(You can use the images we provided, or images in your textbook or lab manual, or you can search
online for blood smear images by entering Microscopic images of blood into your search engine.)
Red blood cells, Monocytes, Lymphocytes, Neutrophils, Eosinophils, and

DNA Barcoding Project
DNA Barcoding Project – Individual DNA Sequence Analysis Worksheet
Please answer the following questions for each sample that you had sequenced:
(DO NOT USE TRACK CHANGES)
Sample (Sequence) Name: 08–03–MJ–A_COI_FOR.ab1
1. At what base pair (bp) does the good quality sequence start (e.g. G35)? _____C46______ Do not
crop the sequence until Step 4. Highlight the first base, take a screen shot of the waveform (should
be full length, not just a few bases) and paste in a screen shot of this region of the DNA sequence
waveform highlighting the start base here:
2. At what bp does the good quality sequence end (e.g. C655)? ______A653________
Highlight the base, take a screen shot of the waveform, and paste in a screen shot of this region of
the DNA sequence waveform highlighting the start base here:
Crop the poor quality regions from 5' and 3' ends of the sequence.
3. Are there any bases (Ns) that need to be edited? Yes: ___ No: __X__
a) If yes, then make the appropriate changes to ALL the Ns in the sequence. Include a screen shot of
the waveform for the first three changes you made.
Save the edited waveform so that you can go back to it later. Paste the edited sequence here:
b) If No changes need to be made to the sequence, save the cropped waveform so that you can go
back to it later. Paste the cropped sequence here:

Unknow Lab Report
Introduction The purpose of this lab was to identify unknown bacteria cultures using various
differential tests, and my unknown bacteria is #17. The identification of these unknown cultures was
accomplished by separating and differentiating possible bacteria based on specific biochemical
characteristics. Whether the tests performed identified specific enzymatic reactions or metabolic
pathways, each was used in a way to help recognize those specifics and identify the unknown
cultures. The differential tests used to identify the unknown cultures were Gram stain, Catalase,
Mannitol Salt Agar (MSA), Blood Agar, Novobiocin, Coagulase, and DNAse (Alachi, 2007).
Rebekah Worley February 21, 2012 Mitchell Section 4 Biol 311 Staining and ... Show more content
on Helpwriting.net ...
This is important in the medical field because identification of unknown bacteria can help treat a
patient by knowing the contributing source of a disease. Also knowledge of different bacteria helped
others make antibiotics used today. This lab was completed by using the methods learned thus far in
identification of bacteria. There are many reasons for identifying an unknown bacterium. The
reasons range from medical purposes, such as determining if the unknown could cause ailments in
living things or knowing what microorganisms are needed to make antibiotics to other purposes
such as knowing the exact microorganism has to be used to make certain foods. This experiment
was done by applying methods in order to identify an unknown bacterium. An unknown bacterium
was handed out by the lab instructor. The methods that have been learned so far in identifying
bacteria were applied to this unknown. Procedures were followed as stated in the lab manual and
biochemical test handouts. The first procedure that was done was a gram stain followed by a streak
of the unknown on a TSA plate in order to determine the gram reaction and observe the colony
morphology. After that, specific biochemical tests were performed for gram positive, since unknown
number five was determined to be gram positive rod. The other tests were performed in this order:
Mannitol Salt (MSA) streak, Blood Agar streak, Catalase test, Nitrate Reduction test, and Phenyl

Identify and Investigate an Unknown Microorganism
INTRODUCTION In the past, and even in modern times like today, it has been vital to distinguish
and determine the identities of microorganisms in the world. These identities are not only important
in knowing what agent causes various diseases and the treatment to be used, but also in
understanding how microbes can be beneficial and valuable to the human body and life as a whole.
With that being said, upon beginning this lab, the purpose of this study was to identity and
investigate an unknown microorganism by applying the methods that were previously learned and
practiced in the microbiology laboratory portion of class.
METHODS AND MATERIALS Upon beginning the unknown lab, I was given the opportunity to
choose an unknown broth tube. This tube contained our unknown microorganism and it was my job,
based upon the testing methods learned throughout the semester to distinguish which microbe I had
chosen. The goal at this point was to create a reserve plate and a working. This was completed by
inoculating one TSA plate thoroughly in order to secure a lot of the growth. This plate became my
reserve plate. The working plate was created by using the Streak Method that was introduced at the
beginning of the semester. With this method, I would soon be able to visualize and record my
microbial growth and colony characteristics. These plates were incubated for a week as that is the
time span between classes. When returning the class the following week, I obtained both my

Phylogenetic Analysis of Thermophilic Bacteria
We report the community of thermophilic bacteria cultivated from Tanjung Sakti Hot Spring in
South Sumatera Indonesia that has temperature 80 – 91 0C and pH 7 – 8. Based on phylogenetic
analysis, the 16 sequences of 16S rRNA gene fragments obtained from the community clustered
within four distinct genera as Anoxybacillus, Geobacillus, Brevibacillus, and Bacillus. Two
sequences that have 96% similarity with data sequences in GenBank, are potentially as novel
species/sub species.
Hot spring is a unique area that characterized by high temperature and has a great diversity of
natural environments. Understanding of thermophilic microbial diversity has opened up a lot of
information about microbial interactions with the environment. The ... Show more content on
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Colonies formed was purified again with inscribed repeated several times in an agar medium.
DNA extraction from microbial culture
Microbial chromosomal DNA was isolated using Protein Purification Kit (Promega). Pellet cells
derived from microbial cultures were resuspended in 300 mL cell lysis solution, incubated at room
temperature for 10 minutes, then added 300 mL nuclei lysis solution and 2 mL RNase and incubated
at 37 ° C for 15 min. Next, add 300 mL of protein precipitation, and centrifuged 13,000 rpm for 10
min at 20 ° C. To the filtrate was added 300 mL of chloroform: isoamilalkohol (24:1), vortex and
centrifuged at 16,000 rpm for 30 seconds, the top layer is taken. The treatment is done 2 times.
Subsequently, 0.6 volume of isopropanol was added and incubated at room temperature for 60
minutes, centrifuged at 13,000 rpm for 15 minutes. DNA pellet formed was washed with 70%
ethanol and then dried. DNA pellet is then dissolved in 50 mL ddH2O.
16S rRNA gene amplification
16S rRNA gene fragment was amplified by PCR using primers 27F and 1492R (Baker et.al, 2003,
Frank, et.al 2008). Amplification was performed by 30 cycles (denaturation 95 ° C for 30 s,
annealing 55 ° C for 60 s, chain extension 72 ° C for 90 seconds) with an initial denaturation 95 ° C
for 3 min and a final chain extension of 72 ° C for 5 min . Taq DNA polymerase enzyme (GoTaq
Green Master Mix from Promega) was used for the amplification reaction according to standard
usage.

Microbiology Lab Chap 1 Essays
Observing Bacteria and Blood
Cynthia Alonzo, M.S. Version 42–0249–00–01
Lab Report Assistant This document is not meant to be a substitute for a formal laboratory report.
The Lab Report Assistant is simply a summary of the experiment's questions, diagrams if needed,
and data tables that should be addressed in a formal lab report. The intent is to facilitate students'
writing of lab reports by providing this information in an editable file which can be sent to an
instructor.
Exercise 1: Viewing Prepared Slides
Questions
A. ... Show more content on Helpwriting.net ...
The thickness of glass that covers the specimen slide also affects the ability one has to focus the
image. If the glass is too thick for the objective lens then one will have a difficult time getting a
focused view (Alonzo p55).
● Resolution:
The resolution in microscopy terms refers to the numerical aperture of the objective lens. The higher
the numerical number the better the resolution of the image; also the shorter the wavelength the
better the resolution (Alonzo p55).
● Contrast:
Contrast is directly related to the illumination system and can be adjusted by changing the intensity
of the light and the diaphragm. Chemical stains applied to the specimen can also enhance contrast
elements (Alonzo p56)
B. What is the purpose of immersion oil? Why does it work?
The purpose of using immersion oil is to help view bacteria that would not be able to not be seen
otherwise. The immersion oil that is put on the slide between the objective and the slide to prevent
the loss of light because of bending light rays as they pass through the air. The oil in turn enhances
the resolving power of the microscope. (Alonzo p62).

Exercise 2: Observing Bacteria Cultures in Yogurt Questions A. Describe your observations of the
fresh yogurt slide.
The yogurt slide had small particles that were constantly moving. They were small and round like
the Cocci form of bacteria as well.
B. Were there observable differences between your fresh

Lab Report : Isolating And Identifying Bacteria Essay
Laboratory Report: Isolating & Identifying Bacteria
Introduction: Through the conduction of numerous experiments, the identity of two bacterial isolates
was determined. The tested specimen was an unknown sample of a mixed culture of two different
species of bacteria. The first step that was taken was obtaining a pure culture of each species of
bacteria by isolating one species from the other. Once isolation was complete, the isolated cultures
were tested using procedures that had been performed during previous lab sessions. A gram stain
was performed on the two isolates. The isolate which had tested gram negative was then tested for
the presence of cytochrome C and lactose fermentation. For the gram positive isolate, cell shape was
determined and a catalase test was performed.
Each mixed culture that was tested had one gram positive and one gram negative bacterial species.
The possible species of bacteria that could have been isolated from the mixtures included the
following: Bacillus subtilis, Corynebacterium glutamicum, Escherichia coli, Staphylococcus aureus,
Enterococcus faecalis, Enterobacter aerogenes, Salmonella enterica, and Pseudomonas aeruginosa.
The identities of the unknown species were determined through comparing the experimental data
against data acquired from earlier experimentation.
Another purpose of this experiment is to stress the importance of knowing the identity of a
microorganism. Knowing the species of microorganism present in a sample provides a

Hepg2 Cells
Design study
The design study in this write up below is a research on HepG2 cells also known as "cells which are
human hepatocytes". The variables which are chosen to be tested on the cells are different types of
saturated fatty acids and the accumulation occurred on the cells.
Hypothesis
There will be no difference between the palmitic and stearic fatty acids which accumulate on the
HepG2 cells.
Null hypothesis
There is a difference between the palmitic and stearic fatty acids on the HepG2 cells.
Variables
Variables in such a study as this are infinite. It would be very costly and time consuming to get a
sufficient outcome. This is because there are too many factors available to adjust although
concentration being one big factor which ... Show more content on Helpwriting.net ...
Communication skills: I have acquired them from my course, work placement in a hospital for the
past year, the sport which I do, group work, my job as a MOT tester and having worked in a garage
for past 5 years in communicating with various customers.
Computing skills: I have gained this from my course which enabled me to use Microsoft excel and
other various forms of database software to store information.
My concern with people: if someone I know personal is having something bad to eat I try to advise
them in having something much healthier.
Open minded: I am very kind and warm person to be with which is vital for one to approach patients
Cope well under pressure: I have acquired this skill from years of balancing family, work and study
life.
Hard working: this is shown through achieving one of my greatest passions in my life which is
owning a Porsche from the age of 19.
Determination: the sport which I do which is wrestling has taught me on how to become a determine
person in what I

Microbiology Lab Report
Microbiology involves the study of microbes and their relevant scientific roles. The purpose of this
lab report is to use the methods and techniques acquired from the microbiology course to identify an
unknown bacterium. The assigned culture for this report is Unknown 28. Various laboratory
techniques were performed in this process in order to draw conclusions as to what microorganism
the unknown sample may contain.
Before proper tests can be performed, the most important aspect to laboratory procedures are aseptic
techniques. These techniques are crucial to ensure that no contamination occurs during the culturing
process (1). Although the exact steps may vary depending on the media and type of transfer, the
main components of the aseptic techniques ... Show more content on Helpwriting.net ...
Controls are especially important when it comes to identifying unknown microbes as it is done
within this report. Positive controls serve as a comparison or model of how the performed test
should react if the microbe tested is positive. This enables the experimenter to compare results and
determine if their culture is positive or negative for the reactions. In contrast, the negative controls
serve to model what the test should look like if nothing is done or if the organism tested is negative.
For every laboratory exercise performed in this course, there are positive and negative control
demonstrations available for students to reference. These are very useful in aiding students when
they are determining the result of their unknown culture

Microbiology Labs
MBK Lab 01 – Lab Report Name: ____________________ Section: ___________________
EXPERIMENT 1
TITLE: Observing Bacteria and Blood
OBJECTIVE: To gain functional knowledge of microscope operations through practical applications
of a microscope in the observation of bacteria and blood.
PROCEDURES: Using the microscope, an oil immersion lens and observing Bacteria Cultures in
Yogurt . Preparing a Blood Slide and observing Blood:
After reviewing the section of the manual as instructed I cleaned the ocular lenses and prepared the
slides. I made required adjustments to the microscope and ocular distances for view during
experiment. I practiced using six prepared slides that were in the kit to ensure I was viewing ...
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I examined all three slides under the microscope. After observing the slides I flushed the specimens
down the drain and disinfected the area with bleach solution. After 42–72 hours I assessed the
growth patterns of the tube and noted that the tube that contained the swab became yellow stained
and the tube that contained the agar and tablet dissolved a little and some of the content drifted to
the surface of the tube and created a film.
QUESTIONS:
1. There was no change from the fresh yogurt and the cultured yogurt. After 24 hours of sitting in a
dark environment it became fermented and liquidy.
Mouth Swab – looks like coccobacillus; plaque: looks like single baccilus; Thick multi–layered –
positive gram stain; colorless moving particles that resemble droplets clustered together
Yeast: looks like tetrad; moving particles, no stain; colorless moving particles
Plaque: thick multi–layered clusters – gram positive stain; solid stable particles, non moving Were
you able to identify specific bacterial morphologies?
Yes I was able to identify some examples as I have previously stated.
What is the difference between direct and indirect staining? Did the smears appear different in each
type of staining? Why or why not?
Direct Staining involves crystal violet and staining bacterial cells causing a negative reaction;

Indirect staining involves staining but results are positive with pink solutions allowing bacteria to be
viewed more accurately. These reactions are

Lab Report On Gram-Negative Bacteria
In the world of microbiology it is vitally important to be able to discern the identities of
microorganisms. Not only is it important in a lab setting but as well as in healthcare in general.
Properly identify what strain of bacteria a person has will aid in the proper medicine and dose given.
Throughout the semester we have learned about different types of bacteria and certain test that can
clearly identify them. The purpose of this lab report is to identify a Gram–positive or Gram–
negative bacterium. Using all the knowledge of procedures and lab techniques identify the unknown
and discuss all the tests you performed.
Introduction
Gram staining is a technique used to determine if the bacteria is Gram positive or Gram– negative.
Gram staining procedure uses crystal violet stain, iodine moderator, alcohol decolorizer and safarin
counter stain. In Gram– negative bacteria the primary stain will be washed out with the decolorizer
and it will be stained with the counterstain. Whereas in Gram–positive bacteria the primary stain
will not leave the cell wall. This difference comes from difference in the structure of the cell wall
that retains the stain.
The Gram–positive cell wall is composed of peptidoglycans, a thick layer of protein–sugar
complexes taking up 60–90% of their cell wall. Peptidoglycan is composed of two glucose
derivatives, N–acetylmuramic acid and N–acetylglucosamine alternated and cross–linked by
tetrapeptides that is composed of L–alanine, D–glutamine, L–lysine

Microbio lab report body Essay example
Maura Gongora
12th December, 2014
MCB 3020L– Section 018
Unknown #16
Abstract
This report contains the background information on gram positive and gram negative bacteria,
which will aid in understanding the use of specific laboratory experiments to distinguish between
the two types of bacteria. Included are the materials and methods used to identify the gram positive
and gram negative bacteria and methods which also differentiate between microbes of each group.
The implications of the methods of identification used are also described in this report to give an
explanation as to why a certain route was taken in carrying out experiment 14. The results of the
experiment carried out for the identification of three unknowns are tabulated ... Show more content
on Helpwriting.net ...
Bacteria that can tolerate the high concentration of salt in the media are from the Staphylococcus
genus. A sample of unknown A was also used to stab a gelatin test tube, which contains the
gelatinase enzyme that breaks down the gelatin and changes the media from solid to liquid. A
sample of the same unknown along with a sample of unknown B was then used to stab a citrate test
tube each. The citrate test is used to determine whether the bacteria utilizes citrate as a carbon
source. If the bacteria used the citrate, the color of the media turns green, but if the citrate was not
used, the media remains blue. The color change in the media is due to the presence of the pH
indicator bromothymol blue. Afterwards, a sample of both unknown B and unknown C were used to
make single line inoculations on both an Eosin Methylene Blue (EMB) and a Salmonella Shigella
(SS) plate. Each plate was divided by a a line in half so that unknown B was inoculated on one side
and unknown C was inoculated on the opposite side. The EMB plate contains lactose and dyes eosin
and methylene blue. The media is used to differentiate between lactose and non–lactose fermenters.
The SS plate also contains lactose in addition to bile salts and brilliant green (dye) to select for
species of Salmonella & Shigella. The media also contains some

Identifying Unknown Bacteri Streptococcus Agalactiae
Truman Nord
Biol 231L Sec.3
November 11, 2014
Identifying Unknown Bacteria: Streptococcus agalactiae
Introduction:
This experiment was conducted to find the genus and species of an unknown bacteria prescribed by
the lab teacher, which was unknown bacteria GA3 in my case. Identification of unknown bacteria
techniques are used on an every day basis to figure out what type of bacteria it is and to find the best
method of how to treat a patient with this bacteria (1). All five "I's" of Microbiology were used in
the testing for the unknown culture. Inoculation was used several times to put the unknown culture
into agar plates or into biochemical test tubes. After Inoculation of these tubes or plates, they always
were placed into the incubator for further growth and development. Isolation was used to make sure
we got the correct bacteria we were testing for. After each further isolation, we gram stained the
culture and inspected the culture under a microscope to further help in the identification process of
the unknown bacteria. Multiple tests were done on the unknown culture to make sure we were
confident in what kind of bacteria the unknown was. Many tests were completed on the unknown
such as gram staining and inspection under microscopes to find whether the bacterium is gram
positive or gram negative. Chemical resistance tests were also performed to see if certain chemicals
affected the unknown growth or if it didn't affect the bacteria at all. Each biochemical test

Living The Environment : Bacteria
Living the Environment: Bacteria
Abstract
This experiment depicts the presence as well as the identification of various micro–organisms
including the bacteria, fungi and algae which may be present on the surfaces that are commonly
used. The use of scientific methods allows to check the presence of bacterial as well as fungal
strains in this experiment. The hypothesis taken into consideration was that the Bathroom handle
will contain more bacteria than the other surfaces.
The experiment involved the use of both the positive and negative control in order to the check the
accuracy of the experiment and sterile agar plates were used to grow the organisms obtained from
the various surface under consideration.
The different colonies were obtained from the various surfaces and also they differed in the number.
The white and cream–colored colonies obtained were identified as the coccus, foggy white colonies
as Bacillus and rest colored colonies as Potentially Staphylococcus.
The hypothesis was proved to be wrong as the floor had more colonies and then the toilet seat was
second most populated surfaces. The colonies were observed and identified as that of Coccus,
Bacillus and Potential Staphylococcus. The water on the bathroom handle must had acted as the
vacuum which resulted in less population of the bacteria.
Introduction:
The evolution of the organisms has been along two lines; the organisms with the cell membrane
bound organelles and another lacking the cell membrane

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