Nội dung text 10. COUNTING OF BACTERIA -TOTAL AND VIABLE COUNTING TECHNIQUES.pdf
PHARMD GURU Page 1 COUNTING OF BACTERIA Measurement of microbial growth and physiology is an important parameter of microbial study. This measurement to a great extent depends on the number of microorganisms present in a culture. Growth of microorganisms can be quantitatively measured using various techniques. A) DETERMINATION OF CELL NUMBER: 1) Total count / direct methods: a) Direct microscopic count / Breed method. b) Counting chamber method / Haemocytometer method. c) Proportional count method. d) Electronic counter method. 2) Viable count / indirect method: a) Plate count technique. b) Membrane filter count. B) DETERMINATION OF CELL MASS: 1) Direct method: a) Dry weight measurement. b) Measurement of cell nitrogen. 2) Indirect method: a) Turbidimetric method. C) DETERMINATION OF CELL ACTIVITY: 1) Measurement of biochemical activity (indirect method). COUNTING OF BACTERIA -TOTAL AND VIABLE COUNTING TECHNIQUES TOTAL COUNTING TECHNIQUE DIRECT METHOD VIABLE COUNTING TECHNIQUE INDIRECT METHOD Also called Also called