Submitted to: Journal of Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/1/2005
Publication Date: 9/20/2005
Citation: Prior, R.L., Pittman, H.E., Wu, X., Mckay, S. 2005. Aglycones and sugar moieties alter anthocyanin absorption and metabolism after berry consumption in weanling pigs. Journal of Nutrition. 135:2417-2424.
Interpretive Summary: Many fruits/berries are rich in anthocyanins, which are the pigments that give the dark blue/red colors to berries. Anthocyanins have high antioxidant capacity, but due to their apparent low bioavailability, their possible roles in health promotion in vivo are still in question. The objectives of these studies were to determine the fate of anthocyanins from 3 different berries following a single meal. Weanling pigs were fed, in a single meal, a freeze dried powder of chokeberry, black currant, or elderberry. These berries provided anthocyanins with differences in the basic chemical structure aglycone as well as some unique differences in the sugar moieties which were attached. The relative proportions of the different metabolites depended upon concentrations, amounts consumed, and types of sugar attached to the basic anthocyanin in the berry. All anthocyanins were absorbed intact into the blood stream. However, some were converted to other compounds through metabolism and others were not changed at all. Anthocyanins with multiple sugars attached to the basic anthocyanin structure were excreted in the urine primarily as the intact forms. Over 80% of the anthocyanins containing multiple sugars were excreted in the urine as the intact molecule from black currant, elderberry or Marion blackberry. The data clearly demonstrate that the basic anthocyanin structure and the number of attached sugar moieties can alter the apparent absorption and metabolism of anthocyanins. These studies are critical to the understanding of what components in fruits and vegetables are absorbed which may be responsible for the health-promoting effects of fruits and berries.
Technical Abstract: To investigate the absorption and metabolism of anthocyanins (ACNs) with different aglycones and sugar moieties, weanling pigs (11.4 +/- 3.8 kg) were fed, in a single meal, a freeze-dried powder of chokeberry, black currant, or elderberry at a single dose of 229, 140, or 228 umol total ACN/kg body weight (BW), respectively. These berries provided ACNs with differences in aglycone as well as some unique differences in the sugar moieties. The relative proportions of the different metabolites depended upon concentrations, quantities consumed, and types of glycoside of ACNs in the berry. Delphinidin ACNs were not metabolized to any measurable extent. Cyanidin ACNs were metabolized via methylation and glucuronidation as well as by formation of both derivatives on the same ACN molecule. ACNs with either a di- or trisaccharide attached to them were excreted in the urine primarily as the intact form. Over 80% of the ACN compounds containing rutinose or sambubiose, which were excreted in the urine from black currant, elderberry, or Marion blackberry, were excreted as the intact molecule. The limited metabolism of these ACNs that did occur was via methylation. ACN monoglycosides other than the glucoside were metabolized via methylation and/or glucuronide formation. The monoglucuronide that formed represented a small proportion of the metabolites relative to the methylated or the mixed methylated and glucuronide forms of ACNs. The data clearly demonstrate that the aglycone and the sugar moieties can alter the apparent absorption and metabolism of ACNs.