Culture media in microbiology refers to the solid or liquid substances used to cultivate and grow microorganisms such as bacteria, fungi, and viruses in a laboratory setting. These media provide the necessary nutrients, environment, and conditions for microorganisms to thrive and reproduce. The choice of culture media depends on the specific requirements of the microorganisms being studied, as different organisms have varied nutritional needs and environmental preferences.
The process of growing microorganisms in culture by taking bacteria from the infection site (in vivo or environment) and grow them in artificial environment in the laboratory (in vitro).
Bacteria may require adequate nutrition, optimum pH, temperature and oxygen for growth and multiplication.
Suitable artificial media containing sources of carbon, nitrogen, hydrogen, oxygen, phosphorous and other elements such as sodium, potassium, magnesium, iron and growth factor (Vitamins) in very small amounts have been used for cultivation of microorganism.
When microorganisms are cultivated in the laboratory, a growth environment called a medium is used. The medium may be purely chemical (a chemically defined medium), or it may contain organic materials, or it may consist of living organisms such as fertilized eggs.
Microorganisms growing in or on such a medium form a culture.
A culture is considered a pure culture if only one type of organism is present and a mixed culture if populations of different organisms are present.
When first used, the culture medium should be sterile, meaning that no form of life is present before inoculation with the microorganism.
Chapter 10 Culture media preparation, inoculation.pptFerhanKadir
Culture media are artificially prepared media containing the required nutrients used for propagation of micro organisms.
Once the bacteria are grown we can:
1. Identify them either by presumptive lab diagnosis like Gram
stain or by definitive lab diagnosis like biochemical test
2. Test the antimicrobial sensitivity of the bacteria (drug
testing). This helps to know whether the bacteria are
sensitive or resistant to known antimicrobial drugs.
Culture media in microbiology refers to the solid or liquid substances used to cultivate and grow microorganisms such as bacteria, fungi, and viruses in a laboratory setting. These media provide the necessary nutrients, environment, and conditions for microorganisms to thrive and reproduce. The choice of culture media depends on the specific requirements of the microorganisms being studied, as different organisms have varied nutritional needs and environmental preferences.
The process of growing microorganisms in culture by taking bacteria from the infection site (in vivo or environment) and grow them in artificial environment in the laboratory (in vitro).
Bacteria may require adequate nutrition, optimum pH, temperature and oxygen for growth and multiplication.
Suitable artificial media containing sources of carbon, nitrogen, hydrogen, oxygen, phosphorous and other elements such as sodium, potassium, magnesium, iron and growth factor (Vitamins) in very small amounts have been used for cultivation of microorganism.
When microorganisms are cultivated in the laboratory, a growth environment called a medium is used. The medium may be purely chemical (a chemically defined medium), or it may contain organic materials, or it may consist of living organisms such as fertilized eggs.
Microorganisms growing in or on such a medium form a culture.
A culture is considered a pure culture if only one type of organism is present and a mixed culture if populations of different organisms are present.
When first used, the culture medium should be sterile, meaning that no form of life is present before inoculation with the microorganism.
Chapter 10 Culture media preparation, inoculation.pptFerhanKadir
Culture media are artificially prepared media containing the required nutrients used for propagation of micro organisms.
Once the bacteria are grown we can:
1. Identify them either by presumptive lab diagnosis like Gram
stain or by definitive lab diagnosis like biochemical test
2. Test the antimicrobial sensitivity of the bacteria (drug
testing). This helps to know whether the bacteria are
sensitive or resistant to known antimicrobial drugs.
Navigating Challenges: Mental Health, Legislation, and the Prison System in B...Guillermo Rivera
This conference will delve into the intricate intersections between mental health, legal frameworks, and the prison system in Bolivia. It aims to provide a comprehensive overview of the current challenges faced by mental health professionals working within the legislative and correctional landscapes. Topics of discussion will include the prevalence and impact of mental health issues among the incarcerated population, the effectiveness of existing mental health policies and legislation, and potential reforms to enhance the mental health support system within prisons.
The dimensions of healthcare quality refer to various attributes or aspects that define the standard of healthcare services. These dimensions are used to evaluate, measure, and improve the quality of care provided to patients. A comprehensive understanding of these dimensions ensures that healthcare systems can address various aspects of patient care effectively and holistically. Dimensions of Healthcare Quality and Performance of care include the following; Appropriateness, Availability, Competence, Continuity, Effectiveness, Efficiency, Efficacy, Prevention, Respect and Care, Safety as well as Timeliness.
One of the most developed cities of India, the city of Chennai is the capital of Tamilnadu and many people from different parts of India come here to earn their bread and butter. Being a metropolitan, the city is filled with towering building and beaches but the sad part as with almost every Indian city
Antibiotic Stewardship by Anushri Srivastava.pptxAnushriSrivastav
Stewardship is the act of taking good care of something.
Antimicrobial stewardship is a coordinated program that promotes the appropriate use of antimicrobials (including antibiotics), improves patient outcomes, reduces microbial resistance, and decreases the spread of infections caused by multidrug-resistant organisms.
WHO launched the Global Antimicrobial Resistance and Use Surveillance System (GLASS) in 2015 to fill knowledge gaps and inform strategies at all levels.
ACCORDING TO apic.org,
Antimicrobial stewardship is a coordinated program that promotes the appropriate use of antimicrobials (including antibiotics), improves patient outcomes, reduces microbial resistance, and decreases the spread of infections caused by multidrug-resistant organisms.
ACCORDING TO pewtrusts.org,
Antibiotic stewardship refers to efforts in doctors’ offices, hospitals, long term care facilities, and other health care settings to ensure that antibiotics are used only when necessary and appropriate
According to WHO,
Antimicrobial stewardship is a systematic approach to educate and support health care professionals to follow evidence-based guidelines for prescribing and administering antimicrobials
In 1996, John McGowan and Dale Gerding first applied the term antimicrobial stewardship, where they suggested a causal association between antimicrobial agent use and resistance. They also focused on the urgency of large-scale controlled trials of antimicrobial-use regulation employing sophisticated epidemiologic methods, molecular typing, and precise resistance mechanism analysis.
Antimicrobial Stewardship(AMS) refers to the optimal selection, dosing, and duration of antimicrobial treatment resulting in the best clinical outcome with minimal side effects to the patients and minimal impact on subsequent resistance.
According to the 2019 report, in the US, more than 2.8 million antibiotic-resistant infections occur each year, and more than 35000 people die. In addition to this, it also mentioned that 223,900 cases of Clostridoides difficile occurred in 2017, of which 12800 people died. The report did not include viruses or parasites
VISION
Being proactive
Supporting optimal animal and human health
Exploring ways to reduce overall use of antimicrobials
Using the drugs that prevent and treat disease by killing microscopic organisms in a responsible way
GOAL
to prevent the generation and spread of antimicrobial resistance (AMR). Doing so will preserve the effectiveness of these drugs in animals and humans for years to come.
being to preserve human and animal health and the effectiveness of antimicrobial medications.
to implement a multidisciplinary approach in assembling a stewardship team to include an infectious disease physician, a clinical pharmacist with infectious diseases training, infection preventionist, and a close collaboration with the staff in the clinical microbiology laboratory
to prevent antimicrobial overuse, misuse and abuse.
to minimize the developme
Explore our infographic on 'Essential Metrics for Palliative Care Management' which highlights key performance indicators crucial for enhancing the quality and efficiency of palliative care services.
This visual guide breaks down important metrics across four categories: Patient-Centered Metrics, Care Efficiency Metrics, Quality of Life Metrics, and Staff Metrics. Each section is designed to help healthcare professionals monitor and improve care delivery for patients facing serious illnesses. Understand how to implement these metrics in your palliative care practices for better outcomes and higher satisfaction levels.
The Importance of Community Nursing Care.pdfAD Healthcare
NDIS and Community 24/7 Nursing Care is a specific type of support that may be provided under the NDIS for individuals with complex medical needs who require ongoing nursing care in a community setting, such as their home or a supported accommodation facility.
Telehealth Psychology Building Trust with Clients.pptxThe Harvest Clinic
Telehealth psychology is a digital approach that offers psychological services and mental health care to clients remotely, using technologies like video conferencing, phone calls, text messaging, and mobile apps for communication.
How many patients does case series should have In comparison to case reports.pdfpubrica101
Pubrica’s team of researchers and writers create scientific and medical research articles, which may be important resources for authors and practitioners. Pubrica medical writers assist you in creating and revising the introduction by alerting the reader to gaps in the chosen study subject. Our professionals understand the order in which the hypothesis topic is followed by the broad subject, the issue, and the backdrop.
https://pubrica.com/academy/case-study-or-series/how-many-patients-does-case-series-should-have-in-comparison-to-case-reports/
CRISPR-Cas9, a revolutionary gene-editing tool, holds immense potential to reshape medicine, agriculture, and our understanding of life. But like any powerful tool, it comes with ethical considerations.
Unveiling CRISPR: This naturally occurring bacterial defense system (crRNA & Cas9 protein) fights viruses. Scientists repurposed it for precise gene editing (correction, deletion, insertion) by targeting specific DNA sequences.
The Promise: CRISPR offers exciting possibilities:
Gene Therapy: Correcting genetic diseases like cystic fibrosis.
Agriculture: Engineering crops resistant to pests and harsh environments.
Research: Studying gene function to unlock new knowledge.
The Peril: Ethical concerns demand attention:
Off-target Effects: Unintended DNA edits can have unforeseen consequences.
Eugenics: Misusing CRISPR for designer babies raises social and ethical questions.
Equity: High costs could limit access to this potentially life-saving technology.
The Path Forward: Responsible development is crucial:
International Collaboration: Clear guidelines are needed for research and human trials.
Public Education: Open discussions ensure informed decisions about CRISPR.
Prioritize Safety and Ethics: Safety and ethical principles must be paramount.
CRISPR offers a powerful tool for a better future, but responsible development and addressing ethical concerns are essential. By prioritizing safety, fostering open dialogue, and ensuring equitable access, we can harness CRISPR's power for the benefit of all. (2998 characters)
2. Culture Media
• Culturing bacteria is growing them in vitro (in the lab) on a media that provides the
bacteria with the conditions required for growth.
• It is basically an aqueous solution with added nutrients for bacterial growth.
• Depending on the type and combination of nutrients, there are different types of
media.
3. Types of Culture Media
Based on
Consistency
Solid
Medium
Semi-solid
medium
Liquid (Broth)
medium
Biphasic
medium
4. Classificationof culture media based on
consistency:
• Solid Medium:
• Used for isolating bacteria or for determining the colony characteristics.
• Dispensed in pre-sterilized plastic or glass dishes and glass tubes.
• Generally liquid media that is solidified by the addition of 2% agar which gives the medium consistency of firm
jelly.
• Inoculated by pre-sterilized plastic loops or wire loops.
• Advantages:
• Allows separate colony formation
• Colonial morphology aids in identification
• Films from single colonies can be made and stained
• Number and relative proportion of different bacterial species originally present
in the specimen can be estimated
• Pure culture can be obtained by picking isolated bacterial colonies onto fresh
solid media.
5. Classificationof culture media based on
consistency:
• Liquid Medium: They are dispensed in tubes with caps (either screw capped
bottles or flasks.
• Turbidity in the flask allows the recognition of bacteria.
• Advantages:
• Some bacteria, especially in small numbers, would only grow in fluid media.
• Fluid media with special constituents, like sugar, are widely used to test biochemical
activities of bacteria for identification.
• Disadvantages:
• Identification of bacteria by colonial morphology can’t be done
• No estimate can be made of the numbers or relative proportion of different bacteria
originally present in the specimen.
6. Classificationof culture media based on
consistency:
• Semi-Solid Media or Soft Agar:
• Solid media with only 0.7%agar
• Media is dispensed in narrow tubes
• Used for keeping stock cultures by stab inoculation
• Used to demonstrate the motility of microorganisms
• Biphasic Media: made up of both liquid and solid agar.
7. Types of Media Based on Constituents
Constituents
Basal Differential Enriched Selective
Selective
Differential
8. Types of Media Based on Constituents
• Basal Media: The simplest type of media which includes basic nutrients for
growth of non-fastidious bacteria and can be solid or liquid. (Nutrient Agar and
Nutrient Broth)
• Nutrient Broth: General-purpose liquid basal medium composed of nutrients
(peptone, beef extract) which allows the growth of various microorganisms.
• Nutrient Agar: General-purpose medium supporting growth of a wide range of
non-fastidious organisms. It typically contains 0.5% peptone and 0.3% beef
extract/ yeast extract.
• Chemically, agar is a polymer made up of subunits of the sugar galactose.
9. Types of Media Based on Constituents
• Differential Media: helps differentiate certain bacteria from others based on
culture.The media would contain a substance that Is visibly changed as a result of
the metabolic activities of particular organisms.
• Triple sugar iron (TSI) agar:
• Main ingredients: 0.1% glucose, 1% lactose, 1% sucrose, ferrous sulphate (for H2S
production), phenol red, beef extract, and low concentration of agar (soft agar
cracks on gas production).
• Uninoculated medium is red (pH 7.4) .The medium is poured in test tubes in the
form of slants with a deep butt.
• Tubes are inoculated with the isolated colony of the organism and incubated for
18-24 hrs at 37 degree Celsius.
10. Differential Media
1. Bacteria that ferment glucose only, will release small amounts of acid and give
a red slant (alkaline) and a yellow butt ( acid) :. Shigella and Salmonella.
2. Bacteria that ferment lactose and/or sucrose release big amount of acid and give
a yellow slant (acid) and a yellow butt( acid): . E.coli and Klebsiella. Gas may
appear at the bottom.
3. Bacteria with no carbohydrate fermenting activity will give a red slant
4. Bacteria fermenting glucose only with H₂S production, will give a red slant
(alkaline) and a black butt : H₂S producing Salmonella and some species of
Proteus.
11. Types of Media Based on Constituents
• Enriched Media: Some bacteria are fastidious and their growth requires the
presence of highly nutritive substances: blood, serum , or egg.
1. Blood Agar:
o Enriched and Differential
o Made up of nutrient agar with 5-10% blood added (sheep, horse, or human blood)
o Sterile blood is added to the sterile agar at a temperature of 55 degree Celsius, then
poured in plates or tubes.
o Red in color
o Has a high nutritive value and blood agar is an indicator to help in identifying bacteria
based on their hemolytic activity on the RBC.
12. Blood Agar
• Beta hemolysis: clear circle around the colony. It is produced by complete hemolysis of
RBC ex: Staph. aureus and Strep.pyogenes.
• Alpha hemolysis: greenish circle around the colony. These lyse the cells but don’t break
down the hemoglobin completely leaving greenish methoglobin in the medium ex:
Viridansstreptococcus and Pneumococci.
• Gamma hemolysis: no visible effect on the RBC.No hemolysis or discoloration of blood.
13. Enriched Media
• Chocolate Agar:
❑Heated blood agar
❑Prepared same as blood agar but the temperature is raised to 100 degree Celsius before
pouring them.
❑During heating, the RBCs are ruptures and nutrients are out.
❑Medium can grow organisms like Neisseriaand Haemophilus groups
❑Brown opaque medium.
14. Types of Media Based on Constituents
• Selective Media:This media contains certain substances that can inhibit all but a few
bacteria present on it.The substances could be chemicals, dyes, or antibiotics. They help
with the isolation of specific species from a mixed inoculum.
1- Sabouraud dextrose agar:
Has low pH (around 5.6) favorable for the growth of fungi and slightly inhibitory to
contaminating bacteria in clinical specimens.
This media is used for performing total combined mold and yeast counts.The addition of
antimicrobials is a modification designed to increase bacterial inhibition.
2- Egg saline media: made of 2.5 parts egg yolk and 1 part saline used to culture T.B.
3- Lowenstein Jensen Media: it consists of beaten egg, mineral salts and malachite green
(inhibit the growth of bacteria other than T.B)and glycerin (inhibit the bovine type and
allows the human type to grow).
15.
16. Selective Differential Media
• Additionally to the substances that can inhibit all but few types of bacteria, this type of media
also contains substances that are visibly changed as a result of the metabolic activities of
particular organisms.
1- MacConkey’sMedium:
It is made up of peptone as a nutrient, agar as the solidifying agent, lactose as a test sugar, and
neutral red as the indicator. It changes to pink in the presence of an acid which is produced as a
result of lactose fermentation. Also contains bile salts that inhibits gram +ve bacteria.
It is reddish transparent.
Used to isolate gram negative bacteria like Pseudomonas aeruginosa and Klebsiella pneumonia
Lactose fermenting bacteria produce reddish pink colonies.
Non-lactose fermenting produce white/ colorless/ golden to brown with dark center colonies.
17.
18. Selective Differential Media
2- Mannitol Salt Agar:
Used for isolation of pathogenic Staphylococci specifically Staphylococcus aureus,
mainly with the investigation of this type of food poisoning.
Contains phenol red indicator, mannitol, and 7.5% sodium chloride.
High salt concentration inhibits the growth of most bacteria other than
staphylococci.
On this media, pathogenic Staphylococcus aureus produces small colonies
surrounded by yellow zones. This color change is due to the fermentation of
mannitol by S. aureus producing an acid that changed the indicator from red to
yellow. Other types of bacteria are generally inhibited.
20. Preparation of Media
• With Solid Media:
• Follow the instructions on the container
• Prepare the media in an Erlenmeyer Flask, autoclave bottle, or glass tubes leaving half the
container empty.
• Melt with water on a flame.
• Sterilize in the autoclave
• When the temperature is around 45-50 degree Celsius, Pour the media aseptically into the
culture plates.
• Tilt tubes for slant preparation.
• With liquid Media:
• Follow instruction on the media container for preparation.
• Prepare media in Erlenmeyer flasks, autoclave bottles, or glass tubes leaving half the
container empty.
• Placed in tubes (same for soft agar)
