Studies on mixed populations of human intestinal bacteria grown in single-stage and multistage continuous culture systems.

AUTOR(ES)

Allison, C

RESUMO

Mixed intestinal bacteria were grown for 336 h in two identical single-stage chemostats at low growth rates in a carbohydrate-limited medium. Complex bacterial populations were maintained and anaerobes always outnumbered aerobes. The predominant organisms belonged to the genera Bacteroides, Bifidobacterium, Lactobacillus, Clostridium, Eubacterium, Propionbacterium, Peptococcus, and Peptostreptococcus. Bacteroides species predominated in both fermentors, particularly B. ovatus and B. thetaiotaomicron. A high degree of reproducibility of bacteriological and fermentation product data was obtained in these experiments. When gut contents were inoculated into a five-stage continuous culture system (retention time of 79 or 38 h) containing soya bran, the medium flow rate had little quantitative effect on the formation of acidic fermentation products; however, more oxidized fermentation acids were produced at the higher retention time. Diverse bacterial populations were maintained in every vessel at each flow rate. Bacteroides fragilis group organisms, especially B. ovatus, were numerically the most important. The viability of bacteria decreased through the system, especially at a retention time of 79 h, when the bacteria were growing under severely nutrient-limited conditions.

Documentos Relacionados

• Lipid accumulation in an oleaginous yeast (Candida 107) growing on glucose in single-stage continuous culture.
• Single-Stage Impaction Device for Particle Sizing Biological Aerosols
• Interrupted Aortic Arch in an Adult: Single-Stage Extra-Anatomic Repair
• Use of a three-stage continuous culture system to study the effect of mucin on dissimilatory sulfate reduction and methanogenesis by mixed populations of human gut bacteria.
• Comparison of Maintenance Energy Expenditures and Growth Yields Among Several Rumen Bacteria Grown on Continuous Culture