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DIFFUSIBILITY The quality of being diffusible; capability of being poured or spread out.
What else can I help you with?
How long does it take alcohol to reach your brain?
Alcohol reaches the brain within minutes of consumption, as it is absorbed directly into the bloodstream through the walls of the stomach and small intestine. The effects of alcohol on the brain can be felt within 5 to 10 minutes of consumption.
What if a agar plate is isolated and antibiotic added and result is no growth or inhibition?
This is basically ANTIBIOTIC SENSITIVITY TEST, to test whether the given organism is RESISTANT(no zone of inhibition) or SENSITIVE( zone of inhibition) to the given antibiotic.Zone of Inhibition Testing is a fast, qualitative means to measure the ability of an antimicrobial agent to inhibit the growth of microorganisms.The effectiveness is based upon the size of zone of inhibition,diffusability of antibiotic,size of inoculum,type of media used.example: bacillus organism is inoculated with both PENICILLIN and AMPICILLIN ,zone of inhibition is absent in case of penicillin and present in case of ampicillin, this shows that ampicillin (sensitive) worked effectively when compared to penicillin.
Why to use mueller hinton agar for antibiotic sensitivity test?
Better diffusion of antibiotics is just one reason why MHA is used for antibiotic sensitivity test (ABST). There are several factors that affect the ABST, they are: Disc concentration, diffusability of the drug, nature and composition of the medium, thickness of the medium, pH of the medium, potency of the disc. The pH should be between 7.2 and 7.4. If the pH is too low, certain drugs loose potency (eg. aminoglycosides, quinolones and macrolides) while certain others show excess activity (eg. tetracycline). If the pH is too high then reverse reactions would occur. Excess moisture too affects the reliability of the result. Increased thymidine reverses the inhibitory effect of sulphonamides, MHA has decreased thymidine content. Increased con. of Mg 2+ and Ca 2+ affects the results of aminoglycosides and tetracycline, also reduces zone size in case of P. aeruginosa. Decreased cation increases the zone size. Increased Zn would decrease the zone size of carbapenen group of antibiotics. Some fastedious organisms like Haemophilus sp, N.gonorrheae, S. pneumoniae, S. viridans and beta hemolytic Streptococcusrequire MHA supplemented with 15micro gram per ml NAD, bovine hematin and yeast extract.
