What are the methods used for controlling microbial growth?
The following points highlight the top nine methods used for controlling Microbial Growth. The Methods are: 1. Sterilization by Heat 2. Sterilization by Dry Heat 3. Sterilization by Moist Heat 4.
What are the conditions that limit the effectiveness of microbial control?
Conditions that limit contact between the agent and the targeted cells cells—for example, the presence of bodily fluids, tissue, organic debris (e.g., mud or feces), or biofilms on surfaces—increase the cleaning time or intensity of the microbial control protocol required to reach the desired level of cleanliness.
What is meant by bacteriostatic control of microbial growth?
Control of Microbial Growth: Definitions BacteriostaticAgent: An agent that inhibitsthe growth of bacteria, but does not necessarily kill them. Suffix stasis: To stop or steady. Germicide: An agent that kills certain micoorganisms.
How to control of microbial growth by dry heat?
Control of Microbial Growth: Method # 2. Dry heat is glass-wares or other heat stable solid material used to sterilize many object/articles in the absence of water. The items to be sterilized are placed in an oven at 160 to 170°C for 2 to 3 hours. Microbial death apparently results from oxidation of cell constituents and denaturation of protein.
What are the methods of controlling microbial growth?
The control of microbial growth may involve sterilization, disinfection, antisepsis, sanitization, or degerming. Sterilization is the destruction of all forms of microbial life, with particular attention to bacterial spores.
What is the most widely used method of microbial control?
Heat is the most widely used method of microbial control. -Bacterial endospores exhibit the greatest resistance to disinfection methods. -Vegetative cells vary in their sensitivity to heat. -Both temperature and length of exposure should be considered for adequate sterilization.
Which treatment can reduce microbial population?
1. Sterilization Sterilization is the process of destroying all living organisms and viruses. A sterile object is one free of all life forms, including bacterial endospores, as well as viruses.
What are the three ways to control microbial growth?
Use of Chemicals.Cleaning: Cleaning involves sweeping, wiping, washing and brushing of a material, which removes most of the microbes present on it. ... Low Temperature: ... High Temperature: ... Filter Sterilisation: ... Radiation Sterilisation: ... Removal of Moisture: ... Modified Atmosphere Packaging: ... Lowering of pH:More items...
What is the most commonly used microbial control method in teaching labs?
Sterilization - Sterilization is the most thorough form of microbe control. It kills all microbes on an object or surface, including all bacteria and viruses. It is usually done using a physical method like heat, or a toxic gas like ethylene oxide.
What is most resistant to microbial control?
Endospores are considered the most resistant structure of microbes. They are resistant to most agents that would normally kill the vegetative cells they formed from. Mycobacterial infections are notoriously difficult to treat. Protozoa cysts are quite hard to eliminate too.
How do antibiotics control microbial growth?
Often called bacteriostatic antibiotics, they prevent nutrients from reaching the bacteria, which stops them from dividing and multiplying. Because millions of bacteria are needed to continue the disease process, these antibiotics can stop the infection and give the body's own immune system time to attack.
How does radiation control microbial growth?
Ionizing radiation is the use of short wavelength, high-intensity radiation to destroy microorganisms. This radiation can come in the form of gamma or X-rays that react with DNA resulting in a damaged cell. Non-ionizing radiation uses longer wavelength and lower energy.
Should microbial growth be controlled?
The control of microbial growth is necessary in many practical situations, and significant advances in agriculture, medicine, and food science have been made through study of this area of microbiology. "Control of microbial growth", as used here, means to inhibit or prevent growth of microorganisms.
Why do we need to control microbial growth?
To prevent the spread of human disease, it is necessary to control the growth and abundance of microbes in or on various items frequently used by humans. Inanimate items, such as doorknobs, toys, or towels, which may harbor microbes and aid in disease transmission, are called fomites.
Why is a shorter treatment time needed?
A shorter treatment time (measured in multiples of the D-value) is needed when starting with a smaller number of organisms. Effectiveness also depends on the susceptibility of the agent to that disinfecting agent or protocol. The concentration of disinfecting agent or intensity of exposure is also important.
What are the factors that determine the level of antimicrobial resistance?
The second factor is the level of resistance to antimicrobial treatment by potential pathogens.
What are inanimate objects that help prevent disease?
Inanimate items, such as doorknobs, toys, or towels, which may harbor microbes and aid in disease transmission, are called fomites.
Why is aseptic technique important?
For many clinical purposes, aseptic technique is necessary to prevent contamination of sterile surfaces. Aseptic technique involves a combination of protocols that collectively maintain sterility, or asepsis, thus preventing contamination of the patient with microbes and infectious agents.
What is the second factor in botulism?
The second factor is the level of resistance to antimicrobial treatment by potential pathogens. For example, foods preserved by canning often become contaminated with the bacterium Clostridium botulinum, which produces the neurotoxin that causes botulism.
Which BSL agent requires the fewest precautions?
For example, the lowest BSL, BSL-1, requires the fewest precautions because it applies to situations with the lowest risk for microbial infection. BSL-1 agents are those that generally do not cause infection in healthy human adults.
Is a disinfectant sterile?
Because some microbes remain, the disinfected item is not considered steril e. Ideally, disinfectant s should be fast acting, stable, easy to prepare, inexpensive, and easy to use.
Laboratory Biological Safety Levels
Sterilization
- The most extreme protocols for microbial control aim to achieve sterilization: the complete removal or killing of all vegetative cells, endospores, and viruses from the targeted item or environment. Sterilization protocols are generally reserved for laboratory, medical, manufacturing, and food industry settings, where it may be imperative for certa...
Other Methods of Control
- Sterilization protocols require procedures that are not practical, or necessary, in many settings. Various other methods are used in clinical and nonclinical settings to reduce the microbial load on items. Although the terms for these methods are often used interchangeably, there are important distinctions. The process of disinfection inactivates most microbes on the surface of a fomite b…
Measuring Microbial Control
- Physical and chemical methods of microbial control that kill the targeted microorganism are identified by the suffix -cide (or -cidal). The prefix indicates the type of microbe or infectious agent killed by the treatment method: bactericides kill bacteria, viricides kill or inactivate viruses, and fungicides kill fungi. Other methods do not kill organisms but, instead, stop their growth, making …