The New International Encyclopædia/Aleurone

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ALEURONE, ȧ-lū′rōn (Gk. ἄλευρον, aleuron, wheaten flour). The stored proteid which occurs as minute granules in the food-bearing tissue (endosperm) and embryos of many seeds. The granules are much smaller than starch grains, with which they often occur. They are usually rounded in form (though the so-called proteid crystals of some plant tissues are angular), and may be simple or complex in structure. The more complex form of granule consists, in great part, of amorphous proteid substance, in which lie imbedded a large crystalloid and a much smaller globoid. The crystalloid is an angular mass of proteid material, differing from most true crystals by swelling in water; the globoid is a nearly spherical mineral concretion, consisting mainly of a double phosphate of magnesium and calcium. Seeds rich in aleurone are the castor bean (Ricinus), the Brazil nut (Bertholletia), peas, beans, etc. See Proteins.

NIE 1905 Aleurone - in castor bean cell.jpg

1. A cell from the castor bean, as seen in water, showing roundish aleurone grains imbedded in the protoplasm. In each, one or more crystals, c, and usually a globoid, g.

2. Isolated aleurone grains of the same, as seen in olive oil.