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Test Media

  1. What does TSA stand for?
    Tryptic Soy Agar
  2. What test is associated with TSA media?
    Several (it is a general purpose media)
  3. Is TSA selective or differential?
    Neither, it is general purpose media
  4. What is the pH indicator in TSA?
    Doesn't have one
  5. What does TSA grow?
    Just about any bacteria, but not fastidious ones
  6. What does TSB stand for?
    Tryptic Soy Broth
  7. What test is TSB associated with?
    None in particular (it is general purpose media)
  8. Is TSB selective or differential?
    Neither, it is general purpose
  9. What is the pH indicator in TSB?
    Doesn't have one
  10. What does TSB grow?
    Just about any bacteria, but not fastidious ones
  11. What does SAB stand for?
    Sabouraud agar
  12. What test is SAB used for?
    Not associated with any particular test
  13. What does SAB grow?
    Fungi
  14. How does SAB prevent growth of bacteria on it?
    It is slightly acidic (pH = 5.6)
  15. Is SAB selective or differential?
    Selective (grows fungi, but excludes bacteria)
  16. What is the pH indicator in SAB?
    Doesn't have one
  17. What does BAP stand for?
    Blood Agar Plate
  18. How is BAP made?
    Add 5% sheep blood to TSA
  19. What test is BAP used for?
    Production of hemolysins
  20. Is BAP differential or selective?
    Differential (differentiates pathogenic species of Staph and Strep from non-pathogenic species)
  21. What is the pH indicator in BAP?
    Doesn't have one
  22. How is a positive test indicated in BAP?
    • Alpha hemolysin production will show a brown/green halo around the colonies
    • Beta hemolysin production will show a colorless halo around the colonies
  23. What reagents do you add after incubating BAP?
    None
  24. What is thioglycollate broth used for?
    Grows anaerobes by binding free O2 in the broth to create an anaerobic environment
  25. Is thioglycollate broth selective or differential?
    Differential (what it differentiates is not indicated)
  26. What is the pH indicator in thioglycollate broth?
    Doesn't have one
  27. What test is fermentation broth used for?
    Fermentation of CHO
  28. What CHO are used in fermentation tests?
    Sugars (glucose, sucrose, lactose, mannitol)
  29. What is the pH indicator in fermentation broth?
    Phenol red
  30. How is a positive test result indicated in fermentation broth?
    The indicator will change from red to yellow
  31. What causes the positive result in fermentation broth?
    Production of acidic by-products from fermentation of CHO
  32. What reagents are added after incubation of fermentation broth?
    None
  33. How is 7% NaCl agar made?
    Add 7% NaCl to TSA
  34. Is 7% NaCl agar selective or differential?
    Selective (for G+ cocci)
  35. What is the pH indicator in 7% NaCl agar?
    Doesn't have one
  36. What test is 7% NaCl agar used for?
    Not associated with any test, it is used as a selective culture media
  37. What does EMB stand for?
    Eosin Methylene Blue agar
  38. Is EMB selective or differential?
    Both

    • -- Selects for G- bugs
    • -- Differentiates lactose fermenters vs. non-fermenters
  39. What is the pH indicator in EMB?
    Methylene Blue
  40. How is a positive test result indicated in EMB?
    Lactose fermenters will be black (or black-centered) with a colorless or pink margin
  41. What reagents are added to EMB after incubation?
    None
  42. What test is Simmon's citrate agar used for?
    Citrate test (part of the IMViC series)
  43. What color is Simmon's citrate agar prior to inoculation?
    Green
  44. What is the pH indicator in Simmon's citrate agar?
    Bromthymol blue
  45. What is the Simmon's citrate agar testing for?
    The ability to use sodium citrate as a source of C
  46. How is a positive test indicated in Simmon's citrate agar?
    Color change from green to blue
  47. What reagents do you add to Simmon's citrate agar after incubation?
    None
  48. Is Simmon's citrate agar selective or differential?
    Both (but most often used to differentiate Enterobacteriaceae)
  49. What are the two kinds of Pseudomonas agars?
    P and F (pyocyanin and flourescein)
  50. Why are there two kinds of Pseudomonas agars?
    Each type enhances the production of one pigment and inhibits the other pigment
  51. Are the Pseudomonas agars selective or differential?
    Differential, they distinguish sub-species of P. aeruginosa based on pigment production
  52. What test are the Pseudomonas agars used for?
    Not test in particular, they are used to run down sub-species
  53. What does OF basal media stand for?
    Oxidation/Fermentation basal media
  54. What test is OF basal media used in?
    Oxidation/Fermentation test
  55. What does OF basal media also contain?
    CHO (glucose in our case)
  56. What is the pH indicator in OF basal media?
    Bromthymol blue
  57. How is a positive result indicated in the OF test?
    • Positive for oxidation if the color changes to yellow in ONLY the open tube (the one without oil in it)
    • Positive for fermentation if BOTH tubes are yellow
  58. What reagents are added to the OF basal media after incubation?
    None
  59. What is the purpose of the OF test?
    To differentiate nonenteric G- bugs from enterics

    • -- Enterics are facultative anaerobes that will ferment glucose (turn both tubes yellow)
    • -- Pseudomonas are aerobes that oxidize glucose (turn the open tube yellow)
    • -- Alcaligenes faecalis will do nothing to the tubes
  60. What test is phenylalanine agar used for?
    Phenylalanine test
  61. Is phenylalanine agar selective or differential?
    Differential (distinguishes Proteus and Providencia from other Enterobacteriaceae)
  62. What pH indicator is used in phenylalanine agar?
    None
  63. How is a positive test indicated in phenylalanine agar?
    Formation of a green color
  64. What reagents are added to the phenylalanine agar after incubation?
    FeCl3 [iron (III) chloride or ferric chloride]
  65. What does TSI stand for?
    Triple Sugar Iron agar
  66. What test is TSI used for?
    Production of H2S
  67. Is TSI selective or differential?
    Differential (distinguishes members of the Enterobacteriaceae family)
  68. What is the pH indicator in TSI?
    Phenol red
  69. How is a positive test result indicated in TSI?
    • Black color = H2S production
    • Red slant = - for fermentation of CHO
    • Yellow slant = + for fermentation of CHO
    • Bubbles/tears in slant = CO2 production
  70. What reagents are added to TSI after incubation?
    None
  71. What are the 3 sugars in TSI?
    Sucrose, glucose, and lactose
  72. What test is decarboxylation broth used for?
    Decarboxylation of AA
  73. Is decarboxylation broth selective or differential?
    Differential (helps distinguish members of the Enterobacteriaceae)
  74. What pH indicator is used in decarboxylation broth?
    Bromcresol purple
  75. What AA are in decarboxylation broth?
    Lysine, ornithine, and arginine
  76. What reagents are added to decarboxylation broth after incubation?
    None
  77. How is a positive test result indicated in decarboxylation broth?
    The broth will turn purple and become turbid
  78. What test is starch agar used for?
    Starch Hydrolysis test
  79. Is starch agar selective or differential?
    Differential (distinguishes Enterobacteriaceae)
  80. What is the pH indicator in starch agar?
    Doesn't have one
  81. How is a positive test indicated in starch agar?
    A cleared halo around the growth (indicating the hydrolysis of the starch)
  82. What reagents are added to the starch agar after incubation?
    Dilute iodine sol'n
  83. What test is skim milk agar used for?
    Casein Hydrolysis test
  84. How do you make skim milk agar?
    Add sterile skim milk to TSA
  85. Is skim milk agar selective or differential?
    Differential (distinguishes Enterobacteriaceae)
  86. What is the pH indicator in skim milk agar?
    Doesn't have one
  87. How is a positive test result indicated in skim milk agar?
    Cleared area (zone of hydrolysis) around a colony
  88. What reagents are added to skim milk agar following incubation?
    None
  89. What test is DNAase agar used for?
    DNAase test
  90. Is DNAase agar selective or differential?
    Both

    • -- Selects for G+ Staph and G- bacilli
    • -- Distinguishes both pathogenic Staph from non-pathogenic and Serratia marcesens from other G- bacilli
  91. What is the pH indicator in DNAase agar?
    Doesn't have one
  92. How is a positive test result determined in DNAase agar?
    Clearing of the methyl green dye surrounding the growth
  93. Why is the DNAase test used to distinguish pathogenic Staph (why does it work)?
    The production of DNAase exoenzyme strongly correlates to coagulase production (coagulase is characteristic to Staphylococcus aureus)
  94. What reagents are added to DNAase agar after incubation?
    None
  95. What is the purpose of the DNAase test?
    The primary purpose is to distinguish pathogenic Staph from non-pathogenic, but it can also be used to distinguish Serratia marcesens from other G- bacilli
  96. What test is tryptone broth used for?
    Indole production test (part of the IMViC series)
  97. Is tryptone broth selective or differential?
    Differential (distinguishes Enterobacteriaceae)
  98. What pH indicator is used in tryptone broth?
    Doesn't have one
  99. How is a positive test result determined in tryptone broth?
    Formation of a red color
  100. What reagents are added to tryptone broth after incubation?
    Kovac's sol'n
  101. What does MR/VP stand for?
    • MR = Methyl Red test
    • VP = Voges-Proskauer test
  102. What test is MR/VP broth used for?
    The MR test and the VP test (part of the IMViC series)
  103. Is the MR/VP broth selective or differential?
    Differential (distinguishes Escherichia coli from Enterobacter aerogenes)
  104. What is the pH indicator used in the MR/VP broth?
    Methyl red
  105. What is the CHO in MR/VP broth?
    Glucose
  106. If your MR test is positive, what would you expect your VP test to be?
    Negative (they should result in opposing values)
  107. How is a positive test result determined in the MR/VP broth?
    • MR+ = the color will stay red
    • VP+ = development of a pink or red color
  108. What reagents are added to MR/VP broth after incubation?
    • MR: add 5 drops of Methyl red indicator
    • VP: add 15 drops of Barritt's reagent A and 5 drops of Barritt's reagent B
  109. What does MSA stand for?
    Mannitol Salt Agar
  110. What test is MSA used for?
    No particular test, it is a growth medium
  111. Is MSA selective or differential?
    Both

    • -- Selective for G+ cocci
    • -- Differentiates pathogenic Staph from non-pathogenic
  112. What pH indicator is used in MSA?
    Doesn't have one
  113. What test is Nitrate broth used for?
    Nitrate Reduction test
  114. Is the nitrate broth selective or differential?
    Differential (distinguishes Enterobacteriaceae)
  115. What pH indicator is used in the nitrate broth?
    Doesn't have one
  116. How is a positive test result indicated in nitrate broth?
    • Production of a red color after adding reagents A&B (indicates + for nitrite)
    • Production of a brown/yellow color after adding Nessler's reagent (indicates + for ammonia)
    • Look for bubbles in the Durham tube
  117. What reagents are added to the nitrate broth after incubation?
    • First, add Nitrate Reagent A and Reagent B to test for nitrite
    • Second, add Nessler's reagent to test for ammonia production (we didn't do this)
  118. What test is Mueller-Hinton agar used for?
    The Kirby-Bauer antibiotic evaluation method
  119. Is Mueller-Hinton agar selective or differential?
    Neither, it is simply a growth medium
  120. How is a positive test result determined on Mueller-Hinton agar?
    There will be a zone of inhibition surrounding the antibiotic discs (which you measure the diameter of to determine the effectiveness of the agent)
  121. What test is malonate broth used for?
    Malonate Utilization test
  122. Is malonate broth selective or differential?
    Differential (distinguishes Enterobacteriaceae)
  123. What is the pH indicator used in malonate broth?
    Bromthymol blue
  124. How is a positive test result determined in malonate broth?
    • Blue color = bug used the malonate
    • Yellow color = bug did not use the malonate but did ferment the glucose
  125. What reagents are added to malonate broth after incubation?
    None
  126. What materials are used in the oxidase test?
    Oxistrips (strips of filter paper soaked in Kovac's sol'n)
  127. How is a positive test result determined in the oxidase test?
    Production of a blue color on the oxistrip or the swab
  128. Is the oxidase test selective or differential?
    Neither (because you only test one bug at a time)
  129. What does a positive oxidase test indicate?
    That your tested bug is a Pseudomonas
  130. What does a negative oxidase test indicate?
    That your tested bug is an Enterobacteria
  131. What is the purpose of the oxidase test?
    To differentiate members of Family Pseudomonadaceae from members of Family Enterobacteriaceae
  132. What reagent is used in the catalase test?
    30% H2O2
  133. How is a positive test result determined in a catalase test?
    Formation of bubbles
  134. What is the purpose of the catalase test?
    Distinguishes Streptococcus (-) from Micrococcus (+) and Bacillus (+) from Clostridium (-)
  135. Is the catalase test selective or differential?
    Neither (since you only test one bug at a time)
  136. What materials are used to perform a coagulase test?
    Citrated rabbit plasma (rabbit plasma with sodium citrate added to prevent coagulation)
  137. How is a positive test result determined in the coagulase test?
    Clotting of the plasma
  138. What does a positive coagulase test result indicate?
    Pathogenic Staphylococcus (S. aureus)
  139. What does a negative coagulase test result indicate?
    Non-pathogenic Staphylococcus (S. epidermidis)
  140. Give an example of a G+ bacillus.
    Anything from the following genera:

    • Bacillus
    • Clostridium
    • Mycobacterium
  141. Give an example of a G- bacillus.
    Anything from the following genera:

    • Klebsiella
    • Brucella
    • Escherichia
    • Bordetella
    • Proteus
    • Legionella
    • Pseudomonas
    • Yersinia
  142. Give an example of a G+ coccus.
    Anything from the following genera:

    • Streptococcus
    • Staphylococcus
    • Micrococcus
  143. Give an example of a G- coccus
    Anything from the following genus:

    Neisseria
  144. Give an example of a bug + for capsules
    Klebsiella pneumoniae
  145. Give an example of a bug + for endospores
    Clostridium perfringens
  146. Give an example of a bug + for acid-fast staining.
    Mycobacterium tuberculosis
Author
SeanOHair
ID
116319
Card Set
Test Media
Description
Lab Final content
Updated

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