Comparative Analysis of Mineral Elements and Essential Amino Acids Compositions in <i>Juglans sigillata<i> and <i>J. regia<i> Walnuts Kernels

Abstract

Walnut high nutritional and economic values. The kernel is usually considered to be a good source of minerals and essential amino acids. In this paper, mineral elements (calcium, magnesium, iron, manganese, copper, and zinc) and essential amino acids (phenylalanine, valine, threonine, isoleucine, leucine, methionine, and lysine) composition's of kernels from 11 kinds of walnuts ( Juglans sigillata ) and 17 kinds of walnuts ( Juglans regia ) originated from China were determined by ICP-MS and HPLC, respectively. The order of nutritive mineral elements depending on their content (mg/100g) of samples was Mg> Ca> Zn> Mn> Fe> Cu in J. regia , while the order in J. sigillata was Mg> Ca> Mn> Fe > Zn > Cu. For essential amino acids, the order depending on the content (mg/g) of the essential amino acids in J. regia samples was leucine> isoleucine> valine> phenylalanine> lysine> threonine> methionine, while the order in J. sigillata was leucine> isoleucine> lysine> phenylalanine> valine> threonine> methionine. The kernels of walnuts ( J. regia and J. regia ) are good sources of health foods and dietary supplements. ‘Y029’ in Juglans sigillata and ‘XJ004’ in Juglans regia provided the best profiles of mineral elements and essential amino acids in comparison to others.