Identification of metabolites involved in the biodegradation of the ionic liquid 1-butyl-3-methylpyridinium bromide by activated sludge microorganisms.
Ionic liquids (ILs) are low melting organic salts that potentially comprise wide application due to their fascinating properties and have emerged as promising "green" replacements for volatile organic solvents. Despite their nonmeasurable vapor pressure, some quantities of ILs will soon be present in effluent discharges since they do have significant solubility in water. Recently, the toxic effects of ILs toward aquatic communities have been intensively investigated, but little information is available concerning the biodegradable properties of these compounds. The objective of this study was to identify the metabolites generated during the biotransformation of 1-butyl-3-methylpyridinium by microorganisms in aerobic activated sludge. The obtained results revealed that the alkylpyridinium salt was metabolized through the sequential oxidization in different positions of the alkyl side chains. High-performance liquid chromatography and mass-spectrometry analyses demonstrated that this biodegradation led to the formation of 1-hydroxybutyl-3-methylpyridinium, 1-(2-hydroxybutal)-3-methylpyridinium, 1-(2-hydroxyethyl)-3-methylpyridinium, and methylpyridine. On the basis of these intermediate products, biodegradation pathways were also suggested. These findings provide the basic information that might be useful for assessing the factors related to the environmental fate and behavior of this commonly used pyridinium IL.
Pham
Thi Phuong Thuy
TP
Department of Bioprocess Engineering, Chonbuk National University, Chonbuk 561-756, Republic of Korea.
Cho
Chul-Woong
CW
Jeon
Che-Ok
CO
Chung
Yun-Jo
YJ
Lee
Min-Woo
MW
Yun
Yeoung-Sang
YS
D001673:Biodegradation, Environmental; D001965:Bromides / Q000737:chemistry / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D052578:Ionic Liquids / Q000737:chemistry / Q000378:metabolism*; D013058:Mass Spectrometry; D011726:Pyridinium Compounds / Q000737:chemistry / Q000378:metabolism*; D012722:Sewage / Q000382:microbiology*; D013997:Time Factors
C539248:1-butyl-3-methylpyridinium; D001965:Bromides; D052578:Ionic Liquids; D011726:Pyridinium Compounds; D012722:Sewage