Distribution of soluble amino acids in maize endosperm mutants

Abstract

For human nutrition the main source of vegetable proteins are cereal and legume seeds. The content of total soluble amino acids in mature endosperm of wild-type, opaque and floury maize (Zea mays L.) mutants were determined by HPLC. The total absolute concentration of soluble amino acids among the mutants varied depending on the mutant. The o11 and o13 mutants exhibited the highest average content, whereas o10, fl3 and fl1 exhibited the lowest average content. In general, the mutants exhibited similar concentrations of total soluble amino acids when compared to the wild-type lines, with the clear exception of mutants o11 and fl1, with the o11 mutant exhibiting a higher concentration of total soluble amino acids when compared to its wild-type counterpart W22 and the fl1 mutant a lower concentration when compared to its wild-type counterpart Oh43. For methionine, the mutants o2 and o11 and wild-type Oh43 exhibited the highest concentrations of this amino acid. Significant differences were not observed between mutants for other amino acids such as lysine and threonine. The high lysine concentrations obtained originally for these mutants may be due to the amino acids incorporated into storage proteins, but not those present in the soluble form.