A Microbiologist Is Preparing A Medium On Which To Culture

Microbiology Theory: Media Preparation

Microbiological medium, as well as any other materials that come into touch with it, must be sterile before being inoculated with the required bacteria. Aseptic procedures must be used to ensure that any undesirable or contaminated organisms are not introduced into the bacterial cultures during any subsequent handling. Sterilisation is the full elimination of all microorganisms, including spores, and can be performed by the use of heat, chemicals, radiation, and filtration, among other techniques.

Heat

Denatures and coagulates essential proteins in the body. There are several different types of heat sterilisation.

Red Heat

Sterilization of inoculating wires or loops is accomplished by heating them in a Bunsen flame until they are red hot.

Moist Heat

When bacteria are exposed to wet heat (steam), they are more easily killed than when they are exposed to dry heat. Sterilisation of culture medium, aqueous solutions, and the destruction of wasted cultures are all common applications for this technique. The air must be evacuated first in order to obtain the 121 degrees Celsius required for efficient sterilisation. In order to do this, an autoclave (a technological version of a pressure cooker) is used, which uses automated cycles of heating under pressure for the specified amount of time.

Dry Heat

In most cases, this is used for things that might be corroded by steam or that must be completely dry before being used. Metal devices, glass petri dishes, flasks and pipettes, and cotton wool are examples of what you’ll need. It is common practice to use longer time periods and higher temperatures for dry heat sterilization rather than steam sterilization (for example, steam sterilization at 121°C for 15 minutes vs. dry heat sterilization at 160°C for 120 minutes).

Chemical

Heat is typically used to protect sensitive equipment such as optical instruments and electrical gadgets, which might otherwise be harmed by the heat. Because of the toxicity of the chemicals employed in this process, it is not the most favored method of sterilization. For example, gaseous ethylene oxide alkylates amino, sulfhydryl, carboxyl and hydroxyl groups in microbial cell compounds; formaldehyde, which is used as a fumigant; and hydrogen peroxide vapour, which is utilized in aseptic packaging are all examples of chemicals that are used.

Radiation

This technique is utilized for heat-sensitive materials as well as environmental samples such as soil and sediment, where structural changes caused by heat must be avoided. There are two types of radiation used:

UV

It starts the process of atoms becoming excited, which in nucleic acids can result in lethal mutations. UV radiation is unable to permeate materials and is thus reserved for surface treatments (e.g. Iaminar flow benches, and air and water).

Ionizing Radiation

It has the ability to penetrate samples and cause ionization within cells.

Gamma radiation produced by a 60 Co a source is used to disinfect complex matrices such as soil and food products, among other things. Microorganisms have improved radiation resistance when grown in anoxic conditions (2-5x), as well as when grown in frozen samples.

Filtration

Filtration sterilisation is accomplished by the exclusion of bacteria rather than through their annihilation. It is non-hazardous to the user and is used to handle delicate liquids and gasses. There are three types of filters in use at the moment:

Depth Filters

Fibrous materials such as glass wool or cotton wool are packed into columns to form these structures. The twisting and turning fibers entrap particles and operate as filters; because of their low resistance to flow, they are mostly utilized for gases or as pre-filters for membrane filters, which are prone to being clogged with particles.

Membrane Filters

Fibrous materials such as glass wool or cotton wool are packed into the columns of these structures. As the fibers twist and twirl, they entrap particles and operate as filters. Because they have minimal resistance to flow, they are mostly employed for gases or as pre-filters for membrane filters, which are prone to clogging.

Nucleation Track (Nuclepore) Filters

Very thin polycarbonate films are used to make these filters, which are then treated with nuclear radiation and chemically processed to generate vertical holes that are extremely consistent in size. They are used for the same materials as membrane filters, however they have the drawback of being more quickly clogged than membrane filters.

Media Supplements

Table of the most regularly used media supplements, as well as their methods of sterilization and solubilities All amino acid stock solutions can be autoclaved for 20 minutes at 120 degrees Celsius.

Interaction of Media Components

The following interactions between media components should be observed when doing research where medium composition is crucial (e.g., toxicity studies). For example:* Can be prevented by adding a HEPES buffer to lower phosphate concentrations in the medium;

1: Media Preparation

Objectives for Learning

  • Acquire knowledge on how to create media, how to sanitize it, and how to disseminate it in various ways. TSA plates, TSA slants, and TSB are to be made, and they will be employed in later lab sessions. Understand the fundamentals of an autoclave and how it sterilizes, as well as its operating settings.

On or on a variety of microbiological medium, bacteria and fungus are propagated and cultivated. The medium that is used to cultivate the microbe is dependent on the microorganism that is being isolated or identified, as well as the organism that is being cultured. Different nutrients can be added to the medium to make it richer in protein or sugar, depending on the application. In order to differentiate bacteria based on their metabolic processes, several pH indicators are frequently used: the indicators may turn one color when the pH is slightly acidic, and another color when the pH is slightly basic.

  1. In this assignment, you will prepare an all-purpose medium known as trypticase soy broth and agar.
  2. Although the formulas for these two media are identical, the addition of agar agar (actually, agar agar) an extract from the cell walls of red algae to the liquid media differs from the solid media in that it is more absorbent.
  3. Today, the only time this is done is when creating a unique medium to grow a particular picky organism, in which certain growth factors, nutrients, vitamins, and other ingredients must be added in specific proportions in order for the organism to thrive.
  4. Fortunately, the majority of the bacteria that we wish to culture will thrive on the media that we usually use in the lab, which is a relief.

Because this form of medium has certain unknown elements, as well as unknown proportions in some cases, it is referred to as complex media. Present-day technology makes it quite simple to create sophisticated media:

  • Rehydrate the powder form of the medium
  • Stir and boil the agar medium to dissolve the agar powder (if preparing an agar medium rather than a broth medium)
  • Rehydrate the powder form of the media dispense the material into the tubes Sterilize the tube media in an autoclave
  • Sterilize the agar medium for plate formation in an autoclave and then pour onto sterile petri dishes

STERILIZATION AND THE AUTOCLAVE

Even after microbiological media has been prepared, it must be sterilized due to the possibility of microbial contamination from the air, glassware, hands, and other sources. Within a few hours, there will be thousands of bacteria growing in the medium, and the media must be sterilized as soon as possible to prevent the microorganisms from depleting the available nutrients. The sterilization procedure is a one-hundred percent kill, and it ensures that the medium will remain sterile UNLESS it is exposed to pollutants by the use of less than acceptable aseptic technique or through exposure to the air during the process.

  • Steam is drawn into the chamber through a jacket that surrounds it.
  • At some point, the pressure will rise over 15 pounds per square inch (psi), at which point the timer will begin to count down—usually for 15 minutes, depending on the type of media being used.
  • As a result, the sterilizing conditions for an autoclave are 120 degrees Celsius at 15 pounds per square inch for 15 minutes.
  • Depending on the form that is being created, several methods of distribution are used to deliver the produced material.
  • Slant tubes are sterilized before being placed on a rack that has been tilted to allow the agar to harden in a slanted manner.
  • A sterilizing autoclave is not capable of sterilizing all media or solutions.
  • It is not necessary to make plate media in this lab; instead, you will be producing slant and broth media.
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MATERIALS NEEDED (per table)

  • It is still necessary to sterilize microbiological media after they have been prepared, due to microbial contamination from the air, glassware, and other surfaces. As soon as a few hours have passed, millions of bacteria will have multiplied in the medium, which means it must be sterilized right away before the germs begin to deplete the available nutrients. It is guaranteed that the medium will remain sterile unless it is exposed to pollutants through the use of less than acceptable aseptic technique or by exposure to air during the sterilizing procedure. The autoclave, which is essentially a large steam cooker, is used to sterilize the media. Steam is drawn into the chamber through a jacket that surrounds it. After a particular point in the jacket has been reached by the pressure from the steam, a valve opens, allowing the steam to pass into the chamber. At some point, the pressure will rise over 15 pounds per square inch (psi), at which point the timer will begin to count down—usually for 15 minutes, depending on the type of media being utilized. It is possible to reach temperatures higher than those reached by simply boiling water in a closed container because of the high pressure. This is around 121 0 C. Because of this, the autoclave’s sterilization conditions are 120 degrees Celsius at 15 pounds per square inch for fifteen minutes. The thermal death period for the vast majority of species is fifteen minutes (except some really hardy sporeformers). Depending on the form that is being created, the prepared material is disseminated in a variety of ways. Dispensing broths and agar deeps into tubes is followed by sterilization. In order to allow for the formation of slanted agar, the tubes are sanitized and placed on a rack that is inclined. Sterilization of the agar medium to be placed onto plates is accomplished by first sterilizing the flask and then pouring it. A sterilizing autoclave is not suitable for all media or solutions. As urea, vaccinations, and serum are high-protein solutions that denature when exposed to high temperatures, they might need to be sterilized using a filter method rather than heating. It is not necessary to make plate media in this lab, however you will be producing slant and broth media.

THE PROCEDURE

For a visual representation of the entire production, see the diagram below: The general technique for creating media is illustrated in Figure 1.

  1. Make the TSB (broth) by placing 250ml of distilled water into a 500ml or 1L flask and letting it sit for 10 minutes. Place the stir bar in the stir plate and turn it on so that the surface is just slightly stirred. This flask should contain 3.25 grams of TSB powder, which should be allowed to dissolve completely (will happen quickly). At this point, there is no need to apply heat. Once the powder has been completely dissolved, pipette out 5ml green cap
  2. And

Pour 250ml of distilled water into a 500ml or 1L flask and set it aside while you make the TSB (broth). Stirring with the stir bar and stirring with the stir plate will just slightly disrupt the surface. This flask should have 3.25 grams of TSB powder in it, and you should allow it to dissolve (will happen quickly). At this point, there is no need to use heat. Remove a 5ml green cap when the powder has been dissolved.

  1. Add 2 grams of agar powder to the remaining solution (about 100mL) while stirring constantly. The following stage will require you to apply heat to the solution combination. To begin, you should be aware that when the temperature of agar rises beyond 100 degrees Celsius, the substance has a significant tendency to boil over. Once you notice steam pouring out of the flask, you should have someone in your party keep an eye on it at all times. Remove the mixture from the hot plate as soon as there is any indication that it is about to boil (paper towels around the flask neck). DO NOT just turn off the heat and leave the flask to sit in the kitchen. It is possible that the metal plate may retain a substantial amount of heat, and shutting off the heat will not prevent the flask from overheating. Folded paper towels help you to hold the flask neck securely while avoiding burning your palm
  2. Have you read step four? Okay, then you may bring the heat up to the ninth setting (not High). Make certain that the magnetic bar is constantly swirling the solution
  3. As the agar dissolves, the solution will turn clear and darker tan in color. Remove it from the heat and pipette out 5ml aliquots into 15 tubes for slants (see note below) (will not be BE slants until removed from autoclave and tilted to the side to solidify). Yellow caps should be used to cover the slant tubes. The remainder of the AGARMEDIUM in the flask will be poured into a single large flask for the entire class.

Add 2 grams of agar powder to the remaining fluid (about 100mL), stirring constantly. The following step will need you to heat the mixture. To begin, you should be aware that when the temperature of agar rises beyond 100 degrees Celsius, the substance has a high potential to boil over. Once you notice steam pouring out of the flask, someone in your company should keep an eye on it at all times. Removing it off the hot plate as soon as it shows signs of being on the verge of boiling is critical (paper towels around the flask neck).

It is possible that the metal plate may retain a large quantity of heat, and shutting off the heat will not keep the flask from boiling over.

If everything is in order, you may put the heat up to 9.

Make certain that the magnetic bar is constantly churning the solution; as the agar dissolves, the solution will turn clear and darker tan in colour.

Yellow caps should be placed on the slant tubes. The remainder of the AGARMEDIUM in the flask will be poured into a single large flask for the entire class;

  1. Distribute all of the tubes you have pipetted out on the instructor’s table, together with the remainder of your melted agar, on plastic autoclave racks. All agar slants are placed on one rack, broths are placed in another rack, and so on. Place your used pipets in the pipet holder to be disposed of properly. Remember that these glass pipets are reusable, so please do not discard them.
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Questions

  1. An explanation of what a complex media is. What is the purpose of adding pH buffers to the microorganisms’ growth media? How is it possible for the temperature in the autoclave to get over the boiling point of 212 degrees Fahrenheit? Exactly why do you have to boil the agar solution BEFORE putting it into the tubes? Agar solidifies when the temperature reaches a certain point.

Contributors and Attributions

  • Distinguished Professor of Biology at Richland College, Jackie Reynolds

Preparation of media and cultures

a professor of biology at Richland College named Jackie Reynolds;

Nutrient agar

28 g of nutritional agar powder should be suspended in 1 litre of distilled water. Bring the mixture to a boil to ensure thorough dissolution. Sterilize after each use and dispense as needed.

Nutrient broth

1 litre of distilled water should have 13 g of nutritious broth powder added to it. Make a thorough mix. Sterilize after each use and dispense as needed.

Malt extract agar

18g agar powder should be suspended in 1 litre of distilled water. Bring the mixture to a boil to ensure thorough dissolution. To make one litre of malt extract, use 15g of malt extract. Make a thorough mix. Sterilize after each use and dispense as needed.

Mannitol yeast extract agar

10 g agar should be suspended in 1 litre of distilled water. Heat until the ingredients are dissolved. Add 0.5 g K 2 HPO 4, 0.2 g Mg, and stir well. SO A solution of 4.7H 2 O, 0.2 g NaCl, 0.2 g CaCl, 2.6H 2 O, 10 g mannitol, and 0.4 g yeast extract is prepared. Sterilize after each use and dispense as needed.

Mannitol yeast extract broth

As above, but without the use of agar.

Glucose nutrient broth

Prepare the nutritional broth according to the package directions, but add 10 g of glucose per litre of soup.

Sugar peptone water

1 litre of distilled water should be mixed with 10 g of peptone, 5 g of NaCl, 5 g of sugar, and 20 cm3 of Universal indicator to achieve a pH of 7.4. Sterilize after each use and dispense as needed.

Tributyrin agar

The product is delivered fully assembled. Heat to melt the ingredients, then dispense aseptically. The nutritional agar may be made by mixing 1 percent tributyrin with the water.

Glucose yeast extract broth

1 litre of distilled water should have 10 g of peptone, 5 g of NaCl, and 3 g of yeast extract added to it. Sterilize after each use and dispense as needed.

Glucose yeast extract lemco broth

Add 10 g of Lemco (meat extract) to a cup of glucose yeast extract broth and mix thoroughly.

Milk agar

Prepare nutritional agar according to the directions above, but use just 900 cm3 of pure water. 20 g of dried skimmed milk should be dissolved in 100 cm3 of purified water. Separately sterilize the items. After chilling to 45-50 degrees Celsius, transfer the milk to the agar aseptically. Dispense in an aseptic manner.

Starch agar

15 g of nutritional agar should be suspended in 100 cm3 distilled water. Bring the mixture to a boil to ensure thorough dissolution. Prepare a suspension by heating 40 g of soluble starch in 100 cm3 of distilled water until it thickens. Allow the mixture to cool before mixing with the nutritional agar solution. Dispense and sterilize the medication.

Iodine solution

Dissolve In 300 cm3 of distilled water, dissolve 1 g of iodine crystals and 2 g of potassium iodine in equal parts. Broth made from cellulose (forTrichoderma reesei)

  • The following ingredients are used: 800 cm 3distilled water
  • 0.1 g CaCl 2
  • 0.5 g (NH 4) 2 SO 4
  • 0.5 g yeast extract powder
  • 0.5 g asparagine
  • Ten grams carboxymethylcellulose
  • One gram potassium chloride
  • PH6.2

Combine the ingredients in a small saucepan and boil slowly, stirring constantly, until the sugar is dissolved.

Microbiology Specimens: Bacteriology and Mycobacteriology

1. Marking and labeling. The proper handling of test requests is dependent on the accuracy of the information provided. Please give at the very least the following information if important clinical information is not accessible, despite the fact that it is highly desirable. A. Patient’s nameb. The location of the specimen collection or the spot where it was obtained c. This document has been dated. The state of the specimen and the lesion. Tests that are desired Obtain the samples in the proper manner.

  1. Provide the patient with a thorough explanation.
  2. Place the container in a sterile environment.
  3. Label the material accurately and submit it to the laboratory as soon as possible.
  4. Prevent the container from being contaminated.

3. The date and time of collecting. a. It is ideal to collect sputum, urine, feces, and other bodily fluids in the early morning and have them submitted to the laboratory the same day. b. The presence of blood

  • A blood culture necessitates the collection of two bottles of blood: one for aerobic culture and another for anaerobic culture. It is necessary to obtain each blood culture from a single venipuncture. If at all feasible, obtain blood specimens prior to the administration of antimicrobial medication. Collect two or three sets early in the sickness
  • If they are negative after 48 hours of growth, repeat the collection process. Microorganisms are shed continually during intravascular diseases such as endocarditis, whereas microorganisms are released occasionally during occult infections. The fever pattern in certain cases of occult infection is predictable, and this is true in other cases. if this is the case, it is better to obtain the blood sample for culture 30 minutes before the fever spike occurs More than three or four cultures are seldom harvested because the yield is small in most cases, and collecting more than this is discouraged. Bacteremia can be caused by virtually any organism, including natural flora. A negative culture result does not always rule out the possibility of bacteremia
  • False-negative findings can arise when germs fail to develop in the culture medium. A positive culture result does not always imply the presence of bacteremia
  • False-positive findings can arise when contaminants develop in the culture medium. Until proven otherwise, Gram-negative bacilli, anaerobes, and fungi should all be treated as potential pathogens. The most difficult interpretation challenge is determining whether an organism that is typically considered normal skin flora is actually a genuine pathogen
  • This is the most difficult interpretation problem.
Clinical Disease Suspected Culture Recommendation Rationale
*Mandell Gl, Bennett JE, Dolin R, eds.Mandell, Douglas, and Bennett’s Principles and Practice of Infectious Diseases.5th ed. Philadelphia, Pa: Churchill Livingstone; 2000: 867-868.
Sepsis, meningitis osteomyelitis, septic arthritis, bacterial pneumonia Two sets of cultures − one from each of two prepared sites. Draw for the second culture after a brief time interval (30 minutes) and then begin therapy. Assures sufficient sampling in cases of intermittent or low level bacteremia. Minimize the confusion caused by a positive culture resulting from transient bacteremia or skin contamination.
Fever of unknown origin (eg, occult abscess, empyema, typhoid fever etc) Two sets of cultures − one from each of two prepared sites. Draw for the second culture after a brief time interval (30 minutes). If cultures are negative after 24 to 48 hours obtain two more sets, preferably prior to an anticipated temperature rise. The yield after four sets of cultures is minimal.
Endocarditis:
Acute Obtain three blood culture sets within two hours, then begin therapy. 95% to 99% of acute endocarditis patients (untreated) will yield a positive in one of the first three cultures.*
Subacute Obtain three blood culture sets on day one, repeat if negative after 24 hours. If still negative or if the patient had prior antibiotic therapy, repeat again. Adequate sample volume despite low level bacteremia or previous therapy should result in a positive yield.
Immunocompromised host aids:
Septicemia, fungemia, mycobacteremia Obtain two sets of cultures from each of two prepared sites. Low levels of fungemia and mycobacteremia frequently encountered.
Age Bottle(s) Total Blood Volume Blood Culture Set
≥15 years old 1 Aerobic (8 to 10 mL)1 Anaerobic (8 to 10 mL) 16 to 20 mL 1 Set = 1 Aerobic Bottle and1 Anaerobic Bottle
15 years old 2 Pediatric (1 to 4 mL) 2 to 8 mL 1 Set = 2 Pediatric Bottles
Neonates 1 Pediatric (0.1 to 1 mL) 0.1 to 1 mL 1 Set = 1 Pediatric Bottle
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Procedure for Specific Specimen Collection

Anaerobic Culture is a type of culture that does not require oxygen. Collection of specimens from a prepared location must be done in a sterile environment using a sterile approach. It is essential to avoid contamination with regular flora. Some anaerobes will be destroyed if they come into contact with oxygen for a short period of time. In an ideal situation, pus acquired by needle aspiration via an intact surface that has been aseptically prepared is immediately transferred to anaerobic transport media.

  1. It is also possible to have a good yield by curing the base of an open lesion.
  2. Pulmonary samples can be acquired with the use of transtracheal percutaneous needle aspiration or by physicians who have received specialized training in this method.
  3. If swabs are required, two should be collected: one for culture and one for Gram staining (if applicable).
  4. The following are clinical signs and symptoms that may indicate anaerobic infection:
  • A culture that is anaerobic. Collection of specimens from a prepared location must be done in a sterile environment using a sterile procedure. It is necessary to avoid contact with typical flora. The presence of oxygen for only a few seconds can be fatal to some anaerobes. In an ideal situation, pus acquired by needle aspiration via an intact surface that has been aseptically prepared is transferred straight to anaerobic transport media. Deep aspiration of open lesions with a sterile plastic catheter or needle improves the quality of the sample taken. It is also possible to obtain a decent yield by curing the base of an open lesion. Alternatively, nonbacteriostatic sterile normal saline may be utilized in the event that irrigation is essential. Invasive techniques such as transtracheal percutaneous needle aspiration or physicians who are skilled in this process can be used to acquire pulmonary samples. For anaerobic culture, it is not recommended to take superficial samples (e.g., a swab of the lesion). If swabs are required, two should be collected: one for culture and one for Gram staining, if applicable. Anaerobic culture should not be performed on throat or vaginal tract swabs since they contain bacteria. Anaerobic infection is characterized by the presence of the following clinical signs and symptoms:

Respiratory Tract (Upper Respiratory Tract). The techniques described in this section are for acquiring culture specimens from the nasopharynx and the throat. One method of collecting nasal cultures is to carefully push a thin sterile swab into the nose until it touches the pharynx, spin gently, and remove it from the patient’s nose. 2. A throat culture is collected by inserting a sterile swab into the mouth of the patient and swallowing. If possible, use a tongue blade to prevent oral secretions from contaminating the samples.

  1. Sputum is produced by the lower respiratory tract.
  2. It may be beneficial to rinse the mouth with saline or water (as opposed to mouthwash) to prevent contamination with typical oropharyngeal bacteria.
  3. Initiate a deep cough, followed by expectoration of the sputum into a sterile specimen collecting cup that has been tagged with the patient’s identification.
  4. Do not send saliva (spit) to be cultured for any reason.
  5. An alternate technique, such as the following, may be ordered: a.
  6. Irritation might cause involuntary deep coughing to take place.
  7. An ultrasonic tiny lumen suction catheter is used to gently irritate the trachea, which results in deep, productive coughing.

c.

These are performed in the operating room by the physician throughout the course of the bronchoscopic examination.

The amount of sputum necessary is little, however it must be sputum rather than oral secretions.

6.

Specimens of Wound Exudate on the skin.

Use dry, sterile gauze to gently wipe the region and remove any impurities that have accumulated there.

Breaking the container is not permitted.

Keep the container at room temperature.

When a urine culture is required, take these measures to ensure that the specimen is collected in a clean catch.

Inform patients about the mechanics of midstream collection and the need of obtaining an uncontaminated specimen in a clear and concise manner.

2.

Patients should be advised that the samples must be clear of any contaminating substance that may be present on the genital organs; as a result, they should be encouraged to follow the procedures specified below. Instructions for the Female Patient (a. Instructions for the Male Patient).

  • If you are menstruation, halt the flow by inserting a fresh tampon or using cotton to stop the flow
  • Then continue. Separate the skin folds surrounding the urine entrance
  • This is important. From front to back, wipe the urinary entrance and its environs with a sterile antiseptic pad to disinfect them. In the toilet, begin urinating while maintaining skin fold separation with one hand’s index and middle fingers. Hold off bringing the container into the course of the pee stream until it has formed a strong urine stream. The container should not be touched in the genital area.

Instructions for the Male Patient, Part B (see below).

  • Soapy water should be used to thoroughly clean the end of the penis. Allow it to dry
  • Start urinating into the toilet as soon as possible. Hold back until the pee stream has been well-established before introducing a container into the stream’s path to capture the remaining urine. The container should not be touched in the genital area.

It is necessary to rinse away any cleansing chemicals from the urethral region before to collecting the samples. The collection of a urine specimen from a catheterized patient is accomplished with the use of a sterile needle of 21-23 gauge and a 3-mL syringe. An antibacterial sponge should be used to clean the region around the distal end of the rubber catheter. Insert the needle at a 45-degree angle into the drainage tube, with the tip directed toward the tubing. If urine is not collected after many attempts, slowly lift the catheter tube.

  • 5.
  • Please keep in mind that you should not collect urine specimens from a drainage bag.
  • Please adhere to the following rules for collecting stool samples.
  • A modest quantity, around the size of a walnut, is all that is necessary.
  • Place the specimen in a container containing stool culture transport media (C S vial).
  • Place the swab in a container containing stool culture transport media (C S vial).

Use of Sterile Swab Bacterial Collection Kit

Until the seal on the swab system is broken, it is guaranteed to be sterile. Instructions for usage are as follows: 1. Remove the swab from the container by peeling it open and removing it. 2. Take the cap/swab stick out of the tube and discard it. Gather the relevant specimen and insert the cap/swab into the tube as shown in Step 3. To bring the swab into touch with the transport medium, press the cap down on the swab. 4. On the specimen tube, write the patient’s name as well as the location of the culture site.

  1. Place the specimen in a specimen bag and the completed test request form in the side pouch of the specimen bag.
  2. Keep it at room temperature until needed.
  3. Submit the samples to the laboratory for testing.
  4. In microbiology, it is standard procedure to isolate and identify “significant” organisms from cultures.
  5. Whenever the organisms present are known to be members of the anticipated flora from a specific body location, the result provided is sometimes referred to as “regular (site) flora.” The following is a list of representative flora collected from various body sites and locations.
  • A-Hemolytic agent (Alpha-hemolytic) Species of Streptococcus and Bacillus
  • Coagulase-negative bacteria Species of Staphylococcus
  • Species of Corynebacterium

Flora of the Respiratory System

  • A-Hemolytic agent (Alpha-hemolytic) Neisseria species, not Enterococcus species
  • Streptococcus species, not Enterococcus varieties NonhemolyticStreptococcusspecies

If they are not the dominant pathogens, the following possible pathogens may be present in the normal flora:

  • Coagulase-negative There are several types of Staphylococcus species, as well as the viruses Haemophilus influenzae and Haemophilus parainfluenzae, Moraxella catarrhalis, Neisseria meningitidis, and Streptococcus pneumonia.

Flora of the Genitourinary Tract

  • A-Hemolytic agent (Alpha-hemolytic) No species of Streptococcus that are Enterococcus
  • Coagulase-negative Species of Staphylococcus (if not the most prevalent)
  • Species of Corynebacterium
  • Lactobacillus spp. NonhemolyticStreptococcusspecies

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