A validated method is proposed to check amino acids variability among eighty-nine wheat samples collected from Punjab province of Pakistan during 2012-2013. Orthophthalaldehyde along with 2-mercaptoethanol was used as a derivatizing reagent that showed florescence at detection wavelength of Ex of 340？nm and Em of 450？nm under suitable pH range of 9-10. RP-HPLC-FLD system employed was Agilent 1100 series equipped with Eclipse XDB C-18 column (2.1 × 150？mm, 5？μ) and column temperature was maintained at 40°C. The maximum concentration of aspartic acid, glutamic acid, leucine, arginine, and histidine was found in Vehari (0.496？g/100？g), Rajanpur (1.292？g/100？g), Rahim Yar khan (0.60？g/100？g), Bahawalpur (0.662？g/100？g), and Narowal (0.377？g/100？g), respectively, while the minimum in Narowal (0.13？g/100？g), Vehari (0.706？g/100？g), Narowal (0.339？g/100？g), Muzaffargarh (0.14？g/100？g), and Rahim Yar Khan (0.088？g/100？g) among the samples obtained from districts. Wheat variety Pb-11 contained relatively high aspartic acid (0.297？g/100？g), glutamic acid (0.897？g/100？g), and leucine (0.484？g/100？g) whereas variety Ass-11 had arginine (0.895？g/100？g) and histidine (0.266？g/100？g). The amino acids were found to vary as follows: aspartic acid 0.130–0.496, glutamic acid 0.706–1.292, leucine 0.321–0.6, arginine 0.118–0.895, and histidine 0.088–0.377？g/100？g flour. The accuracy was in the range of 95.88–100.67%, whereas the RSD for precision was not more than 1.40 for all amino acids. 1. Introduction Amino acids are the building block of a major structural and functional component of cell, that is, proteins. Several subunits of amino acids ranging from two to thousand join together through peptide bond and form long chain protein molecules. Proteins provide energy to the body as do carbohydrates, that is, 4？kcal/g [1]. Amino acids in the diet are required by the body to regulate growth, repair, maintenance, and replacement of tissues. Essential amino acids are required in adequate amounts in the daily diet because these cannot be synthesized in the human body [2]. Histidine was initially considered to be essential only for infants, but now studies have revealed their importance in terms of essentiality for adults too [3]. During limited supply of proper diet, histidine level in the body is maintained by degradation of hemoglobin. The body requirement for histidine by world health organization is between 8 and 12？mg/kg per day [4, 5]. Leucine essentiality lies in the fact that it is utilized in the liver, muscle, and adipose tissues. It helps in the formation of sterols
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