Occurrence of Free Amino Acids in the Source Waters of Zhejiang Province, China, and Their Removal and Transformation in Drinking Water Systems

Files
TR Number
Date
2019-12-24
Journal Title
Journal ISSN
Volume Title
Publisher
MDPI
Abstract

Free amino acids (FAAs) are key components of the global nitrogen cycle and important disinfection byproduct (DBP) precursors. The knowledge gap of FAA occurrence in source and engineered water is discussed in this paper. Solid phase extraction and post column derivatization was combined with gas chromatography–mass spectrometry to simultaneously detect μg/L concentrations of FAAs. This method efficiently detects alanine (Ala), threonine (Thr), serine (Ser), valine (Val), leucine (Leu), isoleucine (Ile), proline (Pro), aspartic (Asp), phenylalanine (Phe), and glutamic acid (Glu) with good linearity, accuracy, and precision. An investigation of FAAs in surface waters in Zhejiang Province found concentrations of 1.48–14.73 μg/L Ala, 0.20–2.39 μg/L Thr, 0.41–7.84 μg/L Val, 0.21–6.86 μg/L Ser, 0.11–4.16 μ;g/L Leu, 0.57–1.54 μg/L Ile, 0.24–8.06 μg/L Pro, 0.42–4.73 μg/L Asp, 0.30–3.01 μg/L Phe, and 0.12–3.83 μg/L Glu. Phe and tyrosine (Tyr) exhibited higher trichloromethane (TCM) formation (1029–1148 μg/mmolAA) than dichloroacetonitrile (DCAN) formation (333–347 μg/mmolAA). Asp and Glu demonstrated the opposite trend: higher DCAN (570–1106 μg/mmolAA) formation than TCM (137–506 μg/mmolAA).

Description
Keywords
solid phase extraction, disinfection byproduct precursor, free amino acids, C-DBP, N-DPB
Citation
Yang, Y.; Yu, Q.; Zhou, R.; Feng, J.; Zhang, K.; Li, X.; Ma, X.; Dietrich, A.M. Occurrence of Free Amino Acids in the Source Waters of Zhejiang Province, China, and Their Removal and Transformation in Drinking Water Systems. Water 2019, 12, 73.