Welch R M, House W A
J Nutr. 1982 May;112(5):879-85. doi: 10.1093/jn/112.5.879.
Male rats were used to assess the availability of zinc in soybean seeds (Glycine max, var. 'Amsoy') as affected by maturity of seed, dietary protein source, and exogenous dietary sodium phytate. Seeds were harvested from either 84- (immature) or 120-day-old (mature) plants grown in 65Zn-labeled nutrient solutions that contained either 0.066 or 0.262 ppm zinc as zinc sulfate. Increased zinc supply to plants increased the zinc content of seeds; immature seeds had higher concentrations of zinc than mature seeds. Phytic acid concentration averaged about 0.6 and 1.7% dry weight in immature and mature seeds, respectively. Seeds of each type were incorporated into meals fed to zinc-depleted rats. In experiment 1, rats fed mature, high-phytate seeds absorbed about 60% of the 65Zn in the seeds, whereas rats fed immature, low-phytate seeds absorbed about 89% of the 65Zn (P less than 0.05). In experiment 2, the source of dietary protein (egg albumen or soy protein) did not markedly affect 65Zn absorption by rats fed mature soybean seeds. In experiment 3, dietary sodium phytate (1.76% of diet as phytic acid) depressed (P less than 0.05) 65Zn absorption by about 16 and 44% from mature soybean seeds and zinc sulfate, respectively. Zinc in soybean seeds apparently was as readily available to rats as that reported for other legume and cereal seeds. Moreover, the nutritional quality of soybean seeds with respect to zinc apparently can be increased by increasing zinc supplies to plants.
雄性大鼠被用于评估大豆种子（大豆品种‘Amsoy’）中锌的可利用性，该可利用性受种子成熟度、膳食蛋白质来源以及外源膳食植酸钠的影响。种子采自生长于含65锌标记营养液中的84日龄（未成熟）或120日龄（成熟）植株，营养液中硫酸锌形式的锌含量分别为0.066或0.262 ppm。增加植物的锌供应会提高种子的锌含量；未成熟种子的锌浓度高于成熟种子。未成熟和成熟种子中植酸浓度平均分别约为干重的0.6%和1.7%。每种类型的种子被掺入喂给缺锌大鼠的饲料中。在实验1中，喂食成熟、高植酸种子的大鼠吸收了种子中约60%的65锌，而喂食未成熟、低植酸种子的大鼠吸收了约89%的65锌（P小于0.05）。在实验2中，膳食蛋白质来源（蛋清或大豆蛋白）对喂食成熟大豆种子的大鼠吸收65锌没有显著影响。在实验3中，膳食植酸钠（占饲料的1.76%，以植酸计）分别使成熟大豆种子和硫酸锌的65锌吸收降低了约16%和44%（P小于0.05）。大豆种子中的锌对大鼠的可利用性显然与其他豆类和谷类种子报道的情况一样。此外，可以通过增加植物的锌供应来提高大豆种子在锌方面的营养质量。
