Dosti Mandy Porter, Mills Jordan P, Simon Philipp W, Tanumihardjo Sherry A
Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI 53706, USA.
Br J Nutr. 2006 Aug;96(2):258-67. doi: 10.1079/bjn20061562.
Vitamin A (VA) deficiency is a worldwide public health problem. Biofortifying existing sources of beta-carotene (betaC) and increasing dietary betaC could help combat the issue. Two studies were performed to investigate the relative betaC bioavailability of a betaC supplement to purple, high-betaC orange, and typical orange carrots using Mongolian gerbils (Meriones unguiculatus). In study 1, which used a traditional bioavailability design, gerbils (n 32) received a diet containing orange, purple, or white carrot powder, or white carrot powder +a betaC supplement. In study 2, which included betaC-biofortified carrots, gerbils (n 39) received orange, high-betaC orange, purple, or white carrot powder in their diet. Both studies lasted 21 d and the gerbils were killed to determine the effect of carrot type or supplement on serum and liver betaC, alpha-carotene, and VA concentrations. Liver stores of betaC or VA in the gerbils did not differ between orange and purple carrot diets when equal amounts of betaC from each of the diets were consumed (P>0.05). Both the orange and purple carrot diet resulted in higher liver VA compared with the supplement (P<0.05). High-betaC carrots resulted in more than 2-fold higher betaC and 1.1 times greater VA liver stores compared with typical orange carrots (P<0.05). These results suggest that high-betaC carrots may be an alternative source of VA to typical carrots in areas of VA deficiency. Second, phenolics including anthocyanins and phenolic acids in purple carrot do not interfere with the bioavailability of betaC from purple carrots.
维生素A(VA)缺乏是一个全球性的公共卫生问题。对现有的β-胡萝卜素(βC)来源进行生物强化并增加膳食中的βC有助于解决这一问题。开展了两项研究,以蒙古沙鼠(Meriones unguiculatus)为实验对象,调查βC补充剂与紫色、高βC橙色和普通橙色胡萝卜中βC的相对生物利用度。在研究1中,采用传统的生物利用度设计,沙鼠(n = 32)食用含有橙色、紫色或白色胡萝卜粉,或白色胡萝卜粉+βC补充剂的饮食。在研究2中,纳入了βC生物强化胡萝卜,沙鼠(n = 39)在饮食中食用橙色、高βC橙色、紫色或白色胡萝卜粉。两项研究均持续21天,之后处死沙鼠,以确定胡萝卜类型或补充剂对血清和肝脏中βC、α-胡萝卜素和VA浓度的影响。当食用等量来自每种饮食的βC时,橙色和紫色胡萝卜饮食组沙鼠肝脏中的βC或VA储备没有差异(P>0.05)。与补充剂组相比,橙色和紫色胡萝卜饮食组的肝脏VA含量更高(P<0.05)。与普通橙色胡萝卜相比,高βC胡萝卜使肝脏中的βC含量高出2倍多,VA储备高出1.1倍(P<0.05)。这些结果表明,在VA缺乏地区,高βC胡萝卜可能是普通胡萝卜的一种VA替代来源。其次,紫色胡萝卜中的酚类物质,包括花青素和酚酸,不会干扰紫色胡萝卜中βC的生物利用度。