Structural effects of ionic liquids on microalgal growth inhibition and microbial degradation

• Published in: Environmental science and pollution research international 2016-03, Vol.23 (5), p.4294-4300
• Main Authors: Pham, Thi Phuong Thuy, Cho, Chul-Woong, Yun, Yeoung-Sang
• Format: Article
• Language: English
• Subjects: Activated sludge; Algae; Anions; Aquatic plants; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; biodegradability; Biodegradation; Biodegradation, Environmental; Cations; Chlorophyta - drug effects; Chlorophyta - growth & development; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Health; Environmental science; Fresh Water - chemistry; Fresh Water - microbiology; freshwater; growth retardation; Imidazoles - chemistry; Imidazoles - toxicity; ionic liquids; Ionic Liquids - chemistry; Ionic Liquids - toxicity; Laboratories; Microalgae; Microalgae - drug effects; Microalgae - growth & development; Microbial Consortia - drug effects; Microbial degradation; Microorganisms; Organisms; Pseudokirchneriella subcapitata; Pyridinium Compounds - chemistry; Pyridinium Compounds - toxicity; Research Article; Selenastrum capricornutum; Sewage - microbiology; Sludge; Solvents; Studies; Toxicity; Waste Water Technology; Water Management; Water Pollutants, Chemical - chemistry; Water Pollutants, Chemical - toxicity; Water Pollution Control
• ISSN: 0944-1344; 1614-7499
• DOI: 10.1007/s11356-015-5287-8

In the present study, we investigated structural effects of various ionic liquids (ILs) on microalgal growth inhibition and microbial biodegradability. For this, we tested pyridinium- and pyrrolidinium-based ILs with various alkyl chain lengths and bromide anion, and compared the toxicological effects with log EC₅₀ values of imidazolium-based IL with the same alkyl chains and anion from literature. Comparing determined EC₅₀ values of cationic moieties with the same alkyl chain length, pyridinium-based ILs were found to be slightly more toxic towards the freshwater green alga, Pseudokirchneriella subcapitata, than a series of pyrrolidinium and imidazolium except to 1-octyl-3-methylimidazolium bromide. Concerning the biodegradation study of 12 ILs using the activated sludge microorganisms, the results showed that the pyridinium derivatives except to 1-propyl-3-methylpyridinium cation were degraded. Whereas in case of imidazolium- and pyrrolidinium-based compounds, only n-hexyl and n-octyl substituted cations were fully degraded but no significant biodegradation was observed for the short chains (three and four alkyl chains).