Some commonly used physical agents in controlling microbial growth are; Show
1. Heat:
Some of the techniques for sterilization which utilize heat are- i. Steam under pressure: eg. Autoclave ii. Boiling: it only kills vegetative cells but not endospores iii. Pasteurization: it only kills harmful bacteria present in milk and beverages. iv. Fractional sterilization or tyndallization: it is effective even for bacterial endospore v) Incineration: it kills microorganism by burning vi) Hot air sterilization: it is dry heat method for sterilization of materials which may be damaged by moist heat such as powder, oils, pipette etc 2. low temperature:
3. Radiation:
i. Non ionizing radiation:
ii. Ionizing radiation:
4. Desiccation:
5. Lyophilization ( freeze drying):
6. Osmotic pressure:
7. Filtration:
Physical agents to control microorganisms
What are the 3 possible ways to control the growth of bacteria?Methods of Controlling Microorganism Growth
HEAT - The easiest, effective way to control microbial growth is to use a FLAME. BOILING - Will not kill bacterial spores, so may not be sterile. AUTOCLAVE - Spores are killed with exposure to autoclave.
What are two physical methods of microbial control?For thousands of years, humans have used various physical methods of microbial control for food preservation. Common control methods include the application of high temperatures, radiation, filtration, and desiccation (drying), among others.
What are microbial control agents?Microbial biological control agents (MBCAs) are applied to crops for biological control of plant pathogens where they act via a range of modes of action. Some MBCAs interact with plants by inducing resistance or priming plants without any direct interaction with the targeted pathogen.
What controls 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 are the 6 methods of physical control of microorganisms?HEAT - Denatures proteins; Moist heat is more effective than Dry heat.. Boiling - vegetative cells are killed within minutes. ... . Steam under pressure - AUTOCLAVE. ... . Pasteurize - kills vegetative bacteria. ... . Dry Heat - Baking - 160oC (320oF) for 2 hours, or 170oC (338oF) are common sterilizing treatments.. Incinerate.. |