Variations in faecal bacterial enzyme activities and associations with bowel function and diet in elderly subjects.
Daily and inter-individual variations of faecal bacterial beta-glucuronidase and beta-glucosidase activities and their associations with parameters of bowel function were studied in 10 residents of an old people's home during two 1-week periods 2 weeks apart. The effect of sampling method (a spot sample vs an aliquot of the homogenized sample from a total daily collection) on the activities of these enzymes and that of urease was also assessed. Intestinal transit time was determined using the radio-opaque Sitzmark; capsules, and questionnaires on bowel function and intakes of fluids and fibre-containing foods were completed. The mean (95% confidence interval) beta-glucuronidase and beta-glucosidase levels were 3.08 (2.75-3.41) and 11.53 (10.79-12.26) nmol min-1 mg protein-1. Daily variations in enzyme activities within individuals were not significant (P = 0.277 and 0.990, respectively), whilst those between individuals were highly significant (P = 0.000). Faecal frequency correlated negatively with beta-glucuronidase and urease, but no other associations of the enzyme activities with parameters of bowel function and diet were observed. beta-Glucuronidase and beta-glucosidase were not affected by the sampling method, while significantly higher urease was obtained by spot sampling as compared with the aliquot representing the total daily collection. Large inter-individual variations in faecal enzyme activities should be taken into consideration when planning experiments and interpreting results on these faecal parameters.
Mykkänen
H
H
Department of Clinical Nutrition, University of Kuopio, Finland. hannu.mykkanen@messi.uku.fi
Laiho
K
K
Salminen
S
S
D000368:Aged; D000369:Aged, 80 and over; D001426:Bacterial Proteins / Q000378:metabolism*; D005243:Feces / Q000201:enzymology*; D005260:Female; D005769:Gastrointestinal Motility; D005966:Glucuronidase / Q000378:metabolism; D006801:Humans; D008297:Male; D013997:Time Factors; D014510:Urease / Q000378:metabolism; D001617:beta-Glucosidase / Q000378:metabolism
D001426:Bacterial Proteins; D001617:beta-Glucosidase; D005966:Glucuronidase; D014510:Urease