Nassar Nagib M A, Sousa M V
Departamento de Genética e Morfologia, Universidade de Brasília, Brasília, DF, Brasil.
Genet Mol Res. 2007 May 11;6(2):292-7.
Cassava roots have a low-protein content (0.7-2%). Amino acids such as lysine and methionine are also low, and some research reports have indicated the absence of methionine. The amino acid profiles of a common cassava cultivar and an interspecific hybrid, namely ICB 300, were determined using the computerized amino acid analyzer Hitachi L-8500. The interspecific hybrid has 10 times more lysine and 3 times more methionine than the common cassava cultivar: lysine content was 0.010 g per 100 g in the common cassava cultivar while it reached 0.098 in the interspecific hybrid. Methionine in the common cassava cultivar was 0.014 g per 100 g whereas it reached 0.041 g per 100 g in the interspecific hybrid. Total amino acid content in the common cassava cultivar was 0.254 g per 100 g viz. a viz. 1.664 g per 100 g in the interspecific hybrid. The genetic variability of the profile and quantity of amino acids indicate the feasibility of selecting interspecific hybrids that are rich in both crude protein and amino acids. This is the first report of high true protein in cassava root.
木薯根的蛋白质含量较低(0.7 - 2%)。赖氨酸和蛋氨酸等氨基酸含量也很低,一些研究报告表明木薯根中不存在蛋氨酸。使用日立L - 8500型计算机化氨基酸分析仪测定了一种常见木薯品种和一个种间杂交品种(即ICB 300)的氨基酸谱。该种间杂交品种的赖氨酸含量比普通木薯品种高10倍,蛋氨酸含量高3倍:普通木薯品种每100克的赖氨酸含量为0.010克,而种间杂交品种达到0.098克。普通木薯品种每100克的蛋氨酸含量为0.014克,而种间杂交品种达到0.041克。普通木薯品种每100克的总氨基酸含量为0.254克,相比之下,种间杂交品种每100克为1.664克。氨基酸谱和数量的遗传变异性表明,选择富含粗蛋白和氨基酸的种间杂交品种是可行的。这是关于木薯根中高真实蛋白质的首次报道。