Microbial degradation of typical amino acids and its impact on the formation of trihalomethanes, haloacetonitriles and haloacetamides during chlor(am)ination

Removal performance and mechanism of typical amino acids in water by the peroxymonosulfate/Fe3O4 nanoparticles

“…Along with the DON removal rate of different amino acids, the results of the previous experiments showed that the removal rate of glutamate was higher than that of histidine and phenylalanine in the Fe 3 O 4 /PMS system, which also led to a decline in the concentration of DCAcAm than other two amino acids. As we all known, amino acids were the precursors of N-DBPs (Bond et al 2011;Zhang et al 2019) and the high removal of glutamate implied that the generation potential of disinfection by-products would be relatively low, which was also consistent with the phenomenon on the formation potential of DCAcAm.…”

“…It could be seen from Table 1 that 20 kinds of free amino acids detected from Xuanwu Lake covered the main categories of amino acids, showing substantial differences in their concentrations. Dissolved organic nitrogen (DON) such as amino acids (AAs) in source waters was the important halogenated N-DBP precursor (Bond et al 2011;Zhang et al 2019). Amino acids (AAs) were characterized by low molecular weights and high hydrophilicities with poor removal efficiencies in conventional water treatment plants (Dotson 2009).…”

Stable Isotopic Labeling and Nontarget Identification of Nanogram/Liter Amino Contaminants in Water

“…A total of 77 of the 154 identified components (50%) were assigned as amino acids and peptides (Figure d). Two free amino acids were identified as Ile and Leu, which have been confirmed to form odorous DBPs in drinking water . We have compiled chemical structures of the 56 dipeptides and N-terminal residues of the 19 polypeptides (comprised of ≥3 amino acids) as well as detailed mass information (precursor ion, product ion, and peak intensity) of the 77 unknown amino compounds identified in the labeled source water (Table S5).…”

“…Two free amino acids were identified as Ile and Leu, which have been confirmed to form odorous DBPs in drinking water. 5 We have compiled chemical structures of the 56 dipeptides and N-terminal residues of the 19 polypeptides (comprised of ≥3 amino acids) as well as detailed mass information (precursor ion, product ion, and peak intensity) of the 77 unknown amino compounds identified in the labeled source water (Table S5). Although interpretation of the 77 unknown amino compounds is still difficult, our work has tentatively determined their presence in source water and may be a reference for further study.…”

“…Environmental water can contain complex organic nitrogenous compounds derived from the decomposition of plants as well as from other anthropogenic discharges such as synthesized polymers, personal care products, and pharmaceuticals. − A significant portion of dissolved organic nitrogenous species (DON) is amino-containing compounds (−NH n , n = 1, 2, e.g., biogenic amines, amino acids, peptides, proteins) in source water. Several difficulties can arise from amino-containing contaminants during drinking water treatment and distribution, and the quality of drinking water can be affected. − For example, during water disinfection, amino acids, and small peptides are difficult to remove during treatment and can react with disinfectants to produce off-taste and toxic disinfection byproducts (DBPs), such as nitrosamines or halogenated nitrogenous DBPs (N-DBPs). − …”