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MICROBIAL GROWTH. By Dr. Ijeoma Nkeiruka Otigbuo. PHYSICAL REQUIREMENTS. Temperature:Psychrophiles, mesophiles, thermophiles, and psychrotrophs. pH: Acidophiles, Extreme halophiles, and facultative halophiles. CHEMICAL REQUIREMENTS. Carbon. Nitrogen, Sulfur, and Phosphorus.
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MICROBIAL GROWTH. By Dr. Ijeoma Nkeiruka Otigbuo.
PHYSICAL REQUIREMENTS. • Temperature:Psychrophiles, mesophiles, thermophiles, and psychrotrophs. • pH: Acidophiles, Extreme halophiles, and facultative halophiles.
CHEMICAL REQUIREMENTS. • Carbon. • Nitrogen, Sulfur, and Phosphorus. • Trace Elements. • Oxygen: Obligate aerobes, Facultative anaerobes, Obligate anaerobes, Aerotolerant anaerobes, and Microaerophiles. • Organic Growth Factors.
TOXIC FORMS OF OXYGEN. • Singlet oxygen. • Superoxide free radicals. • The hydroxyl radical.
CULTURE MEDIA. • Chemically Defined Media. • Complex Media. • Anaerobic Growth Media and Methods. • Special Culture Techniques. • Selective and Differential Media. • Enrichment Culture.
OBTAINING PURE CULTURES. • Streak Plate Method.
PRESERVING BACTERIAL CULTURES. • Deep Freezing. • Lyophilization. • Cryopreservation.
GROWTH OF BACTERIAL CULTURES. • Bacterial Division. • Generation Time. • Phases of Growth: Lag, Log,Stationary, and Death.
DIRECT MEASUREMENT OF MICROBIAL GROTW. • Pate Counts. • Serial Dilutions. • Pour Plates and Spread Plates. • Filtration. • Most Probable Number Method. • Direct Microscopic Count.
ESTIMATION OF NUMBERS BY INDIRECT METHODS. • Turbity. • Metabolic Activity. • Dry Weight.