1 / 25

Anaerobic Culture Methods

Anaerobic Culture Methods. Reducing media Contain chemicals (thioglycollate or oxyrase) that combine O 2 Heated to drive off O 2. Anaerobic Culture Methods. Anaerobic jar. Figure 6.5. Anaerobic Culture Methods. Anaerobic chamber. Figure 6.6. Capnophiles Require High CO 2. Candle jar

tausiq
Download Presentation

Anaerobic Culture Methods

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Anaerobic Culture Methods • Reducing media • Contain chemicals (thioglycollate or oxyrase) that combine O2 • Heated to drive off O2

  2. Anaerobic Culture Methods • Anaerobic jar Figure 6.5

  3. Anaerobic Culture Methods • Anaerobic chamber Figure 6.6

  4. Capnophiles Require High CO2 • Candle jar • CO2-packet Figure 6.7

  5. Selective Media • Suppress unwanted microbes and encourage desired microbes. Figure 6.9b–c

  6. Differential Media • Make it easy to distinguish colonies of different microbes. Figure 6.9a

  7. Enrichment Media • Encourages growth of desired microbe • Assume a soil sample contains a few phenol-degrading bacteria and thousands of other bacteria • Inoculate phenol-containing culture medium with the soil and incubate • Transfer 1 ml to another flask of the phenol medium and incubate • Transfer 1 ml to another flask of the phenol medium and incubate • Only phenol-metabolizing bacteria will be growing

  8. A pure culture contains only one species or strain. • A colony is a population of cells arising from a single cell or spore or from a group of attached cells. • A colony is often called a colony-forming unit (CFU).

  9. Streak Plate Figure 6.10a–b

  10. Preserving Bacteria Cultures • Deep-freezing: –50°to –95°C • Lyophilization (freeze-drying): Frozen (–54° to –72°C) and dehydrated in a vacuum

  11. Reproduction in Prokaryotes • Binary fission • Budding • Conidiospores (actinomycetes) • Fragmentation of filaments

  12. Binary Fission Figure 6.11

  13. Figure 6.12b

  14. If 100 cells growing for 5 hours produced 1,720,320 cells:

  15. Figure 6.13

  16. Figure 6.14

  17. Direct Measurements of Microbial Growth • Plate counts: Perform serial dilutions of a sample Figure 6.15, step 1

  18. Plate Count • Inoculate Petri plates from serial dilutions Figure 6.16

  19. Plate Count • After incubation, count colonies on plates that have 25-250 colonies (CFUs) Figure 6.15

  20. Direct Measurements of Microbial Growth • Filtration Figure 6.17

  21. Direct Measurements of Microbial Growth • Multiple tube MPN test. • Count positive tubes and compare to statistical MPN table. Figure 6.18b

  22. Direct Measurements of Microbial Growth • Direct microscopic count

  23. Direct Measurements of Microbial Growth Figure 6.19, steps 1, 3

  24. Estimating Bacterial Numbers by Indirect Methods • Turbidity Figure 6.20

  25. Direct methods Plate counts Filtration MPN Direct microscopic count Dry weight Indirect methods Turbidity Metabolic activity Dry weight Measuring Microbial Growth

More Related