Davis D L, Poneleit C G
Department of Agronomy, University of Kentucky, Lexington, Kentucky 40506.
Plant Physiol. 1974 Nov;54(5):794-6. doi: 10.1104/pp.54.5.794.
Kernels were collected from three maize (Zea mays L.) inbreds from 10 days after pollination until kernel maturity. Sitosterol, campesterol, and stigmasterol were the major sterols at all stages of kernel development. Cholesterol was less than 1% of the dry weight. The three major sterols accumulated during kernel development, but at a rate slower than dry weight. The ratio of the sterols did not vary greatly among the inbreds. At maturity, the three inbreds, Wf9, Oh43, and Ky226, had sterol levels of 325, 228, and 173 micrograms per kernel, respectively. Sitosterol accounted for 75 to 85% of the sterol. The relative amount of stigmasterol decreased during the linear phase of development, while sitosterol increased in the free fraction and campesterol increased in the steryl ester fraction.Free sterols and steryl esters were the major sterol fractions and steryl glycosides and acylated steryl glycosides were only minor components during kernel development. Free sterol content decreased rapidly in two maize inbreds between 10 and 26 days after pollination, but partially recovered in one of the inbreds during final stages of development. In the same two inbreds the steryl ester content reached a maximum during the late stages of linear kernel growth.
从授粉后10天直至籽粒成熟，采集了三种玉米（Zea mays L.）自交系的籽粒。在籽粒发育的所有阶段，谷甾醇、菜油甾醇和豆甾醇都是主要的甾醇。胆固醇含量低于干重的1%。三种主要甾醇在籽粒发育过程中积累，但积累速率比干重慢。这些自交系中甾醇的比例变化不大。成熟时，Wf9、Oh43和Ky226这三个自交系的籽粒甾醇含量分别为每粒325、228和173微克。谷甾醇占甾醇的75%至85%。在发育的线性阶段，豆甾醇的相对含量下降，而游离部分的谷甾醇增加，甾醇酯部分的菜油甾醇增加。游离甾醇和甾醇酯是主要的甾醇组分，而甾醇糖苷和酰化甾醇糖苷在籽粒发育过程中只是次要成分。在授粉后10至26天之间，两个玉米自交系的游离甾醇含量迅速下降，但其中一个自交系在发育后期部分恢复。在同样的两个自交系中，甾醇酯含量在籽粒线性生长后期达到最高。
