title: Serum beta-glucuronidase activity in response to fruit and vegetable supplementation: a controlled feeding study.
abstract: BACKGROUND
  Fruit and vegetable (F&V) intake may lower the risk of some cancers. One hypothesized, but understudied, chemopreventive mechanism is that plant food constituents inhibit beta-glucuronidase, an acid hydrolase that deconjugates glucuronides.
  
  
  METHODS
  We conducted a crossover feeding trial in 63 healthy women and men ages 20 to 40 years to examine the effect of diet on serum beta-glucuronidase activity. Participants were randomized to two 2-week experimental diets with an intervening washout period: a diet high in selected citrus fruit, crucifers, and soy (F&V) and a diet devoid of fruits, vegetables, and soy (basal). Serum beta-glucuronidase activity was measured during the preintervention, F&V, and basal periods. Linear mixed models were used to obtain effect estimates and 95% confidence intervals (95% CI).
  
  
  RESULTS
  We observed statistically significantly higher beta-glucuronidase activity during the F&V than the basal diet (ratio, F&V versus basal diet, 1.09; 95% CI, 1.05-1.13; P < 0.01). These results were probably due to decreased beta-glucuronidase activity during the basal diet (ratio, basal period versus preintervention, 0.93; 95% CI, 0.87-0.98; P = 0.01) rather than increased enzyme activity during the F&V diet (ratio, F&V period versus preintervention, 1.01; 95% CI, 0.96-1.06; P = 0.64). Response to the experimental diet did not differ by sex (P(interaction) = 0.30), but there was a suggestion of a short-term diet effect at 8 versus 15 days (P(interaction) = 0.06).
  
  
  CONCLUSIONS
  This intervention of selected F&V did not lower beta-glucuronidase activity. Further investigation is needed regarding what other foods and phytochemicals may influence beta-glucuronidase activity and effect modifiers of this relation.
authors.affiliation: Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109-1024, USA.
authors.forename: Sonia S
authors.initials: SS
authors.lastname: Maruti
authors.forename: Jyh-Lurn
authors.initials: JL
authors.lastname: Chang
authors.forename: Jo Ann
authors.initials: JA
authors.lastname: Prunty
authors.forename: Jeannette
authors.initials: J
authors.lastname: Bigler
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Schwarz
authors.forename: Shuying S
authors.initials: SS
authors.lastname: Li
authors.forename: Lin
authors.initials: L
authors.lastname: Li
authors.forename: Irena B
authors.initials: IB
authors.lastname: King
authors.forename: John D
authors.initials: JD
authors.lastname: Potter
authors.forename: Johanna W
authors.initials: JW
authors.lastname: Lampe
mesh_terms: D000328:Adult; D018592:Cross-Over Studies; D019587:Dietary Supplements; D005260:Female; D005500:Follow-Up Studies; D005638:Fruit; D005966:Glucuronidase / Q000097:blood*; D006801:Humans; D015994:Incidence; D008297:Male; D009369:Neoplasms / Q000201:enzymology / Q000453:epidemiology / Q000517:prevention & control; D012307:Risk Factors; D013053:Spectrophotometry; D014675:Vegetables; D014861:Washington / Q000453:epidemiology; D055815:Young Adult
chemical_list: D005966:Glucuronidase