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item Widmer, Wilbur
item Stinson, William
item Dou, Hauting
item Haun, Carl

Submitted to: National Meeting of Institute of Food Technologists/Food Expo
Publication Type: Abstract Only
Publication Acceptance Date: 7/15/2005
Publication Date: 7/21/2005
Citation: Widmer, W.W., Stinson, W., Dou, H., Haun, C. 2005. Furanocoumarin variation in four grapefruit varieties with respect to maturity. National Meeting of Institute of Food Technologists/Food Expo. Paper No. 104-5.

Interpretive Summary:

Technical Abstract: Grapefruit juice, when consumed with certain orally administered medications has been shown to increase their bioavailability. After more than a decade of research, it has been shown the interaction occurs because a number of grapefruit components cause inhibition of the intestinal enzyme cytochrome P450 3A4. It is now fairly well accepted that the components completely or largely responsible for the CYP3A4 inhibition are naturally occurring furanocoumarin monomers (bergamottin, 6,7-dihydroxybergamottin or DHB) and dimer compounds. Bergamottin, DHB, and 9 dimer compounds were monitored in the juice sacs (edible portion) and peel of four varieties of grapefruit (Marsh White, Ruby Red, Flame, Rio Red) over a two season period. The dimer compounds were more prevalent in juice sacs than the peel, while DHB content was much higher in the peel. Bergamottin was present at equal amounts in the peel and edible juice sacs. On average the Ruby Red variety juice sacs contained approximately 60- 70% less DHB than the Marsh or Flame varieties and 50% less than the Rio Red variety. Bergamotin and total dimer content of the Ruby Red juice sacs was also 45 – 55% lower then the other 3 varieties.