Studies on the Storage Protein in the Seed of Nelumbo Nucifera

• Main Author: 周聖萍
• Other Authors: 童武夫
• Format: Others
• Language: zh-TW
• Published: 1987
• Online Access: http://ndltd.ncl.edu.tw/handle/60620318215966661207

碩士 === 國立臺灣師範大學 === 生物學系 === 75 === 　　The storage protein in the cotyledon of lotus (Nelumbo nucifera Gaertn) has been isolated by sequen-tial extraction according to the solubility of the proteins. Albumin fraction was found to be the major storage protein which constituted approximately 62% of the total protein. The glutelin fraction which was solubilized under highly denaturing condition constituted approximately 2 6% of the total protein. 　　The polypeptides of albumin fraction observed by SDS-PAGE electrophoresis were highly heterogeneous and composed at least seven polypeptide groups. Two polypeptide groups, 99kd and 54-59kd, were purified by ammonium sulfate fractionation and two cycles of Sephadex G-100 gel filtration. Amino acid composition of the 99kd polypeptide has been analyzed. It conteined more glutamic acid/glutamine, glycine and threonine but less aspartic acid/asparagine, isoleucine and tyrosine in compared to other proteins. 　　Accumulation of storage proteins in the cotyledon of developing seed was analyzed. The polypeptide groups increased gradully during early development.while a dramatic change in quantity as well as quality of teh polypeptides were observed in the seventh developing stage. the result indicates that the major storage protein is most activity synthesized during this transit period between sixth and seventh developing stages. 　　Storage protein in the lotus cotyledon was obviously decreased ten days after germination, which might be corresponding with the higher activity of the protease.