anaerobic environment

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Anaerobic environment,hungate technique,microbes involved in 4 stages aidogenesis,acetogenesis,methanogenesis



2. Also microaerophiles like Campylobacter jejuni veryimportant in medial terms For proper diagnosis and for studies of anaerobicenvironments culture techniques are desirable 3. Culture of anaerobes is extremely difficult due to theneed to exclude oxygen, slow growth and complexgrowth requirements Molecular methods based on DNA analysis and directmicroscopy have shown that we are largely ignorant ofthe microbial world and previously unknown diversityhas been discovered 4. Culture methods Anaerobes differ in their sensitivity to oxygen and theculture methods employed reflect this - some aresimple and suitable for less sensitive organisms, othersmore complex but necessary for fastidious anaerobes Vessels filled to the top with culture medium can beused for organisms not too sensitive 5. Most common adaptation of media is the addition of areducing agent, e.g. thioglycollate, cysteine Acts to reduce the oxygen to water, brings down theredox potential -300mV or less. Can add a redox indicator such as rezazurin, pink inthe presence of oyxgen - colourless in its absence 6. Deep culture tubes can be used to test whether anunknown organism is anaerobic/facultative or aerobic Thioglycollate added to culture medium, oxygen onlyfound near top where it can diffuse from air -patternof colony formation characteristic of organisms 7. REDOX POTENTIAL


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