早籼稻米的蛋白质含量及其氨基酸组成

分析了在早季和晚季种植的１８个早籼品种（组合）的精米蛋白质含量及其氨基酸组成．结果表明，稻米蛋白质含量及其氨基酸组成与栽培品种和栽植季节有关，早季略高于晚季；稻米蛋白质普遍缺乏赖氨酸和苏氨酸，并被分别作为稻米的第１和第２限制性氨基酸；各种氨基酸含量的高低顺序在不同品种中基本相似，均以谷氨酸、亮氨酸较高，色氨酸、蛋氨酸较低；蛋白质与氨基酸总量、必需氨基酸总量及天冬氨酸、谷氨酸、丝氨酸、精氨酸、蛋氨酸、异亮氨酸、亮氨酸、苯丙氨酸等呈显著和极显著正相关，而与赖氨酸、色氨酸呈负相关．但只有赖氨酸达显著水准；与其他８种氨基酸呈正相关，但不显著．

Rice Protein Content and Amino Acid Composition in Early indica Rice

This paper analysed the rice protein content (PC) and amino acid(AA)composition in 18 varieties of early indica rice, which planted both in the first cropping and in the second cropping.The results showed that the PC and the AA composition were defferent among varieties studies and affected by growing seasons.It was higher in the first cropping than that in the second cropping,the PC universally lacked lysine and threonine,and of which lysine was the first and threonine was the second limited AA in all of analysed varieties.The order of AA levels for defferent varieties were quite similar,with more glutamic acid and leucine,as well as,less trytophan and methionine.It was also showed that a significantly positive correlation between PC and the all AA contents,necessary AA content,aspartic acid,glutamic acid,serine, arginine, methionune, isoleucine,leucine and phenylalanine content( r= 0.327-0.927 ,n=34),and a not significantly positive correlation between PC and glyine,histidine, threonine, alanine,proline,tyrosine,valine and cysteine content, but a significantly negative correlation between PC and lysine(r=-0. 347),and a not significantly negative correlation between PC and trytophan.