title: Phytoremediation of perchlorate by free floating macrophytes.
abstract: Phytoremediation of perchlorate by free floating macrophytes (Eichornia, Pistia, Salvinia and Lemna) was evaluated in this study. Among the plants tested, Pistia showed 63.8 ± 4% (w/v) removal of 5 mg/L level perchlorate in 7 days, whereas the removal was absent in other plants. Phyto-accumulation (18.2%) and rhizo-degradation (45.68%) were identified as the mechanisms involved in perchlorate removal in Pistia. Whole plant extraction yielded 45.4 μg perchlorate/g dry weight biomass in 7 days period. High intensity of light and presence of nitrate negatively affected perchlorate removal by Pistia. An enrichment of Pistia root homogenate exhibited faster reduction of perchlorate where 100mg/L of the compound was reduced completely in 48 h under anoxic condition. A novel perchlorate reducing bacterium, isolated from Pistia root homogenate enrichment was identified as Acinetobacter sp. NIIST (Genbank JX467695).
authors.affiliation: Environmental Technology, National Institute for Interdisciplinary Science & Technology (CSIR-India), Industrial Estate (PO), Thiruvananthapuram-19, India. krishna@niist.res.in
authors.forename: Krishnakumar
authors.initials: K
authors.lastname: Bhaskaran
authors.forename: Anupama
authors.initials: A
authors.lastname: Vijaya Nadaraja
authors.forename: Soumya
authors.initials: S
authors.lastname: Tumbath
authors.forename: Liji
authors.initials: L
authors.lastname: Babu Shah
authors.forename: Prajeesh
authors.initials: P
authors.lastname: Gangadharan Puthiya Veetil
mesh_terms: D000150:Acinetobacter / Q000378:metabolism*; D029064:Araceae / Q000378:metabolism*; D001673:Biodegradation, Environmental; D018533:Biomass; D031806:Eichhornia / Q000378:metabolism; D019684:Magnoliopsida / Q000378:metabolism; D008969:Molecular Sequence Data; D009566:Nitrates / Q000737:chemistry; D010472:Perchlorates / Q000737:chemistry*; D018517:Plant Roots / Q000382:microbiology; D013472:Sunlight; D013997:Time Factors; D064028:Tracheophyta / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry; D018508:Water Purification / Q000379:methods
chemical_list: D009566:Nitrates; D010472:Perchlorates; D014874:Water Pollutants, Chemical; C494474:perchlorate
keywords: Perchlorate; Phytoaccumulation; Phytoremediation; Rhizodegradation