Agar dilution tubes Agar dilution tubes are mixed cultures diluted in molten agar琼脂稀释管 Useful for purifying anaerobic organisms Colonies Paraffin-mineral oil seal Colonies of oxygen- sensitive anaerobes can be obtained using the agar uebipeW 'Lleey!W pue 6unr shake technique.对氧敏感 的厌氧菌 (b) 2012 Pearson Education,Inc
Microbiology, Shanghai Jiao Tong University Agar dilution tubes are mixed cultures diluted in molten agar 琼脂稀释管 • Useful for purifying anaerobic organisms Agar dilution tubes Colonies of oxygensensitive anaerobes can be obtained using the agar shake technique. 对氧敏感 的厌氧菌
Most-Probable Numbers(MPN) technique最大可能值方法 ©A procedure using s serial dilution of an inoculum in a liquid medium until the final tube or tubes in the series show no growth. Used to estimate number of microorganisms in food,wastewater,and other samples Microbiology.Shanghai Jiao Tong University
Microbiology, Shanghai Jiao Tong University Most-Probable Numbers (MPN) technique 最大可能值方法 A procedure using serial dilution of an inoculum in a liquid medium until the final tube or tubes in the series show no growth. Used to estimate number of microorganisms in food, wastewater, and other samples
FLASH A sample is added to a selective culture medium, and serial dilutions are made from them.The last tube showing growth should have developed from 10 or fewer cells. 1ml (liquid) Enrichment culture By repeating this process or 1 g or natural sample several times,pure (solid) Dilution→ cultures can be obtained 1 ml 1 ml 1ml 1 ml 1ml No Growth Growth growth 9 ml of broth 1/10 (10-1) 102 103 10-4 105 106 2012 Pearson Education,Inc
A sample is added to a selective culture medium, and serial dilutions are made from them. The last tube showing growth should have developed from 10 or fewer cells. By repeating this process several times, pure cultures can be obtained. FLASH
Laser tweezers are useful for lsolating slow-growing bacteria from mixed cultures (a)Principle:A strongly focused laser beam on a Cell bacterial cell creates Beam focus downward radiation forces b Fa,Fb on the cell that Objective lens of microscope allows the cell to be dragged in any direction. Laser beam 理聚焦于细胞的激光可产生向下的 (a) 力，该力可以移动细胞 Optically trapped cell Severing point Capillary tube Mixture of cells (b) Laser Microbiology.Shanghai Jiao Tong University
Microbiology, Shanghai Jiao Tong University Laser tweezers are useful for Isolating slow-growing bacteria from mixed cultures (a) Principle: A strongly focused laser beam on a bacterial cell creates downward radiation forces Fa, Fb on the cell that allows the cell to be dragged in any direction.原 理:聚焦于细胞的激光可产生向下的 力,该力可以移动细胞
Laser tweezers are useful for lsolating slow-growing bacteria from mixed cultures b (b)Isolation:The laser beam can lock onto a single cell present in a Cell mixture in a capillary tube Beam focus and drag the optically a trapped cell away from the Objective lens of microscope other cells.激光可将毛细管中 的细胞锁定，拖其远离其它细胞 Laser beam (a) Optically trapped cell Severing point Capillary tube Mixture of cells (b) Laser Microbiology.Shanghai Jiao Tong University
Microbiology, Shanghai Jiao Tong University Laser tweezers are useful for Isolating slow-growing bacteria from mixed cultures (b) Isolation: The laser beam can lock onto a single cell present in a mixture in a capillary tube and drag the optically trapped cell away from the other cells. 激光可将毛细管中 的细胞锁定,拖其远离其它细胞