Incorporation and metabolism of punicic acid in healthy young humans

The objective of this study was to investigate the incorporation and metabolism of punicic acid (PA, <i>cis</i>9,<i>trans</i>11,<i>cis</i>13-18:3) in healthy young humans. The study was a randomized controlled trial. After 7 days adaptation with sunflower seed kernels supplementation, 30 subjects were then divided into the control and test group (<i>n</i> = 15). The test group was supplemented with <i>Trichosanthes kirilowii </i>(TK) seed kernels containing 3 g of PA per day in the form of triacylglycerols for 28 days. The control group was provided with sunflower seed kernels. After consumption of TK seeds containing 3 g PA per day for 28 days, the proportion of PA was increased from 0.00 to 0.47% in plasma and 0.00 to 0.37% in red blood cell membranes (RBCM), respectively. The proportion of <i>cis</i>9,<i>trans</i>11-18:2 was increased from 0.05 to 0.23% in plasma and 0.03 to 0.17% in RBCM after 28 days of intervention, respectively. Our results suggest that PA can be effectively incorporated into human plasma and RBCM, and is also associated with the increasing proportion of <i>cis</i>9,<i>trans</i>11-18:2 in humans, presumably as a result of metabolism by a saturation reaction. Edible TK seeds could be a potential dietary source of conjugated linoleic acids.<br />