1 Nutrición,Condiciones de Cultivo y Fases de CrecimientoTemperatura: Psicrófilas: crecen óptimamente en temperaturas bajas < 20 grados C. Mesófilas: crecen óptimamente a temperatura ambiente > grados C Flora normal del cuerpo= comensales Termófilas: Crecen a temperaturas altas
2 pH Mayoría Bacterias patógenas: crecen en ambientes de Ph 6.5- 7.5.Algunas toleran ambientes ácidos: flora gastrointestinal Otras como Vibrio cholerae crece en pH alcalinos.
3 Requisitos de oxígeno Aeróbicos Anaeróbicos facultativosMicroaerofílicos capneicosrequieren más CO2 que O2 Anaeróbicos estrictos: oxígeno es letal
4 Gas Pak System GasPak Plus® Hydrogen + CO2 with Safety- Shielded Integral Palladium Catalyst Strip For CO2-enriched anaerobic environment.
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6 Enlace ?module=Book&func=displayarticle&art_id=7 5
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10 http://www. monografias
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14 Phases of Growth 4 Phases 1. Lag Phase 2. Log Phase3. Stationary Phase 4. Death Phase
15 1. Lag Phase Bacteria are first introduced into an environment or media Bacteria are “checking out” their surroundings cells are very active metabolically # of cells changes very little 1 hour to several days
16 2. Log Phase Rapid cell growth (exponential growth)population doubles every generation microbes are sensitive to adverse conditions antibiotics anti-microbial agents
17 3. Stationary Phase Death rate = rate of reproductioncells begin to encounter environmental stress lack of nutrients lack of water not enough space metabolic wastes oxygen pH Endospores would form now
18 3. Stationary Phase Death rate = rate of reproductioncells begin to encounter environmental stress lack of nutrients lack of water not enough space metabolic wastes oxygen pH Endospores would form now
19 4. Death Phase Death rate > rate of reproductionDue to limiting factors in the environment
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