In vitro metabolism of radiolabeled carbohydrates by protective cecal anaerobic bacteria.
Cecal anaerobic bacteria from adult broilers were cultured in media containing .25% glucose or .25% lactose. Media also contained either [14C]-labeled lactose, glucose, galactose, or lactic acid as metabolic tracers. Cultures were analyzed at 4, 8, and 12 h for pH, radiolabeled and unlabeled volatile fatty acids, and lactic acid. The pH values of cultures containing .25% lactose were significantly (P < .05) higher than the pH values of cultures containing .25% glucose. Lactose cultures reached their lowest pH more slowly than glucose cultures. Concentrations of unlabeled volatile fatty acids increased and lactic acid decreased during incubation of the cultures. Radiolabeled sugars and lactic acid were more readily metabolized to volatile fatty acids in media containing lactose than in media containing glucose. The preferred metabolism of [14C]substrates, independent of media carbohydrate, was in the following order: lactic acid > galactose, lactose > glucose. The volatile fatty acids in which radiolabel was most concentrated were acetic acid, propionic acid, or butyric acid.
Hume
M E
ME
USDA, Agricultural Research Service, Food Animal Protection Research Laboratory, College Station, Texas 77845.
Beier
R C
RC
Hinton
A
A
Scanlan
C M
CM
Corrier
D E
DE
Peterson
D V
DV
DeLoach
J R
JR
D000818:Animals; D001421:Bacteria, Anaerobic / Q000378:metabolism*; D050260:Carbohydrate Metabolism; D002432:Cecum / Q000382:microbiology*; D002645:Chickens / Q000382:microbiology*; D003470:Culture Media / Q000737:chemistry; D005232:Fatty Acids, Volatile / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007773:Lactates / Q000378:metabolism*; D019344:Lactic Acid; D013997:Time Factors
D003470:Culture Media; D005232:Fatty Acids, Volatile; D007773:Lactates; D019344:Lactic Acid