Two-dimensional time evolution approach was applied to study corn germ and endosperm-water system. Measurements were made on; (1) germ without water (vacuum evaporation) but with different percentages of oil, (2) germ without oil(chemically extracted) but with different percentages of water and (3) endospermwater system with different percentages of water. Water interacts strongly with germ matrix and considerably decreases T1 of the system, whereas oil almost remains independently with its surroundings. The behavior of low moisture (less then 5% of water) corn germ is the water bound to germ matrix and oil is in the form of oilcell. There are two T1 components in germ matrix-water system. The exchange rates in long T1 group is 57 s-1 from matrix to water and 113 s-1 from water to matrix. In short T1 group, the exchange rate is 245 s-1 from matrix to water and 821 s-1 from water to matrix. At low hydration, the endosperm-water system has one T1 component. The exchange rate from endosperm to water is higher than 37 s-1.%应用核磁共振时域二维弛豫相关谱分析的方法,对玉米胚芽的核磁共振弛豫特性进行了研究.对以下三种样品进行了测定:(1)胚芽不含油(用化学方法蒸馏出)但是含有不同百分含量的水;(2)胚芽不含水(真空蒸发)但是含有不同百分含量的油;(3)含有不同百分含量的水的胚乳-水系统.研究表明随着水含量的增加水的纵向弛豫时间T1减小,表明水与胚芽基质具有强烈的相互作用,而油的纵向弛豫时间T1随着油含量的增加变化很小,表明油与胚芽基质之间没有大的相互作用,油几乎独立地处在胚芽中;对低水分(少于5%)玉米胚芽-水系统,结果表明水是束缚于胚芽基质上,而油则是以油胞的形式存在于胚芽中.在玉米胚芽-水系统中有两个T1弛豫成分,长T1弛豫成分从基质到水的交换率为57 s-1;从水到基质的交换率为113 s-1.短T1成分从基质到水的交换率为245 s-1;从水到基质的交换率为821 s-1.在低水合状态下,胚乳-水系统仅有一个T1弛豫成分.胚乳到水的交换率高于37 s-1.
展开▼
