Simultaneous Detection and Analysis of Free Amino Acids and Glutathione in Different Shrimp

Abstract

An amino acid analyzer method for the simultaneous determination of 20 free amino acids (FAAs) and glutathione (GSH) in Penaeus vannamei (PV), Penaeus vannamei, Penaeus hidulis (PH) and Penaeus japonicus (PJ) were developed. The effects of different concentrations of trichloroacetic acid (TCA) and ethanol on the extraction of free amino acids were investigated, and 120 g·L−1 TCA was found to be ideal. The target analytes were eluted in sodium citrate buffer B1 (pH = 3.3) containing 135 mL·L−1 ethanol and 1 mol·L−1 sodium hydroxide (7 mL) and at the optimizing conversion time of sodium citrate buffer B2 (pH = 3.2) and sodium citrate buffer B3 (pH = 4.0) of 5.6 min, and the effective separation was achieved within 29.5 min. The developed method showed good linearity (R2 ≥ 0.9991) in the range of 1–250 µg·mL−1 with good intra-day and inter-day precision (relative standard deviations ≤ 2.38%) and spike recovery (86.42–103.64%). GSH and cysteine were used to identify marine prawn and freshwater shrimp. Hydroxyproline and serine were used to distinguish PV and Macrobrachium nipponense (MN) from others, respectively. The highest content of the total FAAs was found in PV, and principal component analysis revealed that PV had the highest comprehensive score for FAAs and GSH. Arginine was found to have the greatest influence on shrimp flavor.

Effects of Cooking Processes on Protein Nutritional Values and Volatile Flavor Substances of Silver Carp (Hypophthalmichthys molitrix)

“…The amino acids of the samples were determined according to the methods of Jin et al [21] and Zhang et al [22] with slight modifications. In total, 3 g meat pieces were put into a hydrolysis tube, and we added 15 mL of 6 mol/L hydrochloric acid solution; these were then frozen for 5 min, evacuated to 0 Pa, and then filled with nitrogen, before being sealed and hydrolyzed in an oven at 110 • C for 22 h. After cooling to room temperature (25.0 ± 2.0 • C), the hydrolysate was filtered into a 50 mL volumetric flask and fixed with deionized water.…”

Optimized extraction technology of glutathione from ‘Haidao 86’ germ rice by response surface methodology

“…HDGRP had important development value and could provide sufficient raw materials for the source of GSH.Solvent extraction, chemical synthesis, enzyme synthesis, biological fermentation, and other methods were commonly used to extract GSH(GeorgiouSiafis et al, 2022;Jin et al, 2022;Wang et al, 2021), although chemical synthesis had been eliminated by industrialization because of its low purity and unstable titer. The enzymatic synthesis method had high specificity and high product purity, but its cost was high.…”