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Ligy Philip

Bio: Ligy Philip is an academic researcher from Indian Institute of Technology Kharagpur. The author has contributed to research in topics: Freundlich equation & Chemical oxygen demand. The author has an hindex of 3, co-authored 3 publications receiving 96 citations.

Papers
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TL;DR: Kinetic studies with Pseudomonas aeruginosa using actinides and lanthanides indicated a two-phase metal uptake and EDAX studies revealed replacement of calcium and magnesium ions from biomass by sorbed metal.
Abstract: Kinetic studies with Pseudomonas aeruginosa using actinides and lanthanides indicated a two-phase metal uptake. Equilibrium uptake data of all the metals studied could be fitted to Langmuir as well as Freundlich models. The Scatchard plots showed that there were mainly two types of receptor sites on the cell walls of P. aeruginosa having different affinities for the metal ions. EDAX studies revealed replacement of calcium and magnesium ions from biomass by sorbed metal. Around 85% of the adsorbed metal could be released using citrate buffer (pH 4.0, 0.2 M). Metal desorption was as high as 95% with HCl. Continuous flow studies using P. aeruginosa immobilized on activated alumina gave 80% enhancement of lanthanum removal efficiency compared to the control column. Regeneration of the column resulted in 80% of its initial capacity in succeeding cycles. Journal of Industrial Microbiology & Biotechnology (2000) 25, 1–7.

64 citations

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TL;DR: In this paper, electron paramagnetic resonance (EPR) spectra showed that accumulated copper formed complexes with oxygen and nitrogen which may be the carboxyl groups of cell-wall peptidoglycan and nitrogen atoms of aminosugars or structural proteins.
Abstract: Copper uptake potential of different bacterial strains isolatedfrom contaminated soil was compared. The bacterial strainidentified as Bacillus polymyxa showed maximum copperuptake capacity. An attempt was made to elucidate the site ofinteraction of Cu(II) with B. polymyxa using electronparamagnetic resonance (EPR) studies. The EPR spectra showedthat accumulated copper formed complexes with oxygen andnitrogen which may be the carboxyl groups of cell-wallpeptidoglycan and nitrogen atoms of aminosugars or structuralproteins. The absence of super hyperfine splitting in theg ⊥ region of EPR spectra of treated B. polymyxa cellsafter Cu(II) uptake indicated that copper could be coordinatedwith the oxygen atoms from carboxyl groups of peptidoglycan inthe cell walls.

30 citations

Journal ArticleDOI
TL;DR: Performance of mixed microbial anaerobic culture in treating synthetic wastewater with high Chemical Oxygen Demand (COD) and varying atrazine concentration and performance of hybrid reactors with wood charcoal as adsorbent showed that the higher dose of wood charcoal in hybrid reactor did not improve theAtrazine removal efficiency significantly.
Abstract: Performance of mixed microbial anaerobic culture in treating synthetic wastewater with high Chemical Oxygen Demand (COD) and varying atrazine concentration was studied. Performance of hybrid reactors with wood charcoal as adsorbent, with a dose of 10 g/l and 40 g/l, along with the microbial mass was also studied. All the reactors were operated in sequential mode with Hydraulic Retention Time (HRT) of 5 days. In all the cases, COD removal after 5 days was found to be above 81%. Initial COD was above 1000 mg/l. From a hybrid reactor COD removal after 2 days was observed to be 90%. Atrazine reduction after 5 days by microbial mass alone was 43.8%, 40% and 33.2% with an initial concentration of 0.5, 1.0 and 2.0 mg/l respectively. MLSS on all the cases were almost same. Increasing MLSS concentration by about 2 fold did not increase the atrazine removal efficiency significantly. Maximum atrazine removal was observed to be 64% from the hybrid reactor with 10 g/l of wood charcoal and 69.4% from the reactor with 4...

12 citations


Cited by
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Journal ArticleDOI
TL;DR: In this paper, the authors discuss the possibilities to recover rare earths from industrial waste streams, which contain only low concentrations of rare-earth elements, but are available in very large volumes and could provide significant amounts of rare Earths.

442 citations

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TL;DR: Research on the behaviour of microorganisms in geogenic or anthropogenic metallomorphic environments is an integral part of geomicrobiology and can lead to an understanding of biogeochemical cycles.
Abstract: Research on the behaviour of microorganisms in geogenic or anthropogenic metallomorphic environments is an integral part of geomicrobiology. The investigation of microbial impact on the fate of minerals and geologically significant compounds of mining areas can lead to an understanding of biogeochemical cycles. Metabolic processes of microorganisms are the cause for the dissolution of minerals, and especially pyrite oxidation results in the generation of acid mine drainage which, in turn, leads to heavy metal contamination as a result of mining activities. On the other hand, microbial metabolism can also contribute to the formation of certain ore deposits over geological time. The adaptation to heavy metal rich environments is resulting in microorgansims which show activities for biosorption, bioprecipitation, extracellular sequestration, transport mechanisms, and/or chelation. Such resistance mechanisms are the basis for the use of microorganisms in bioremediation approaches. As only a small part of the worldwide occurring prokaryotes has been described yet, the understanding of the role bacteria play in a geogenic and pedogenic context is very likely to change deeply as soon as more habitat relevant microbial functions can be described. Examples for the identification of microbial processes from case studies may help to advance this field. The strongly interdisciplinary field of bio-geo-interactions spanning from the microorganism to the mineral holds much promise for future developments in both basic research as well as applied sciences. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

366 citations

Journal ArticleDOI
TL;DR: In this paper, the authors consider the biological influence on metal behavior in aqueous environments and propose a mechanistic approach to understand the mechanisms underlying metal dynamics, which encompasses both the geochemical and biological components of this dynamic and complex cycle.

319 citations

Journal Article
TL;DR: Bioremediation and natural attenuation are also seen as a solution for emerging contaminant problems, e.g. endocrine disrupters, landfill stabilization, mixed waste biotreatment and biological carbon sequestration.
Abstract: The term bioremediation has been introduced to describe the process of using biological agents to remove toxic waste from environment. Bioremediation is the most effective management tool to manage the polluted environment and recover contaminated soil. Bioremediation is an attractive and successful cleaning technique for polluted environment. Bioremediation has been used at a number of sites worldwide, including Europe, with varying degrees of success. Bioremediation, both in situ and ex situ have also enjoyed strong scientific growth, in part due to the increased use of natural attenuation, since most natural attenuation is due to biodegradation. Bioremediation and natural attenuation are also seen as a solution for emerging contaminant problems, e.g. endocrine disrupters, landfill stabilization, mixed waste biotreatment and biological carbon sequestration. Microbes are very helpful to remediate the contaminated environment. Number of microbes including aerobes, anaerobes and fungi are involved in bioremediation process.

271 citations

Journal ArticleDOI
TL;DR: Significance of bioremediation with the help of genetically engineered bacteria is in light because of its eco-friendly nature and minimum health hazards other than the physio-chemical dependent strategies, which are less eco friendly and dangerous to life.
Abstract: Bioremediation is an inventive and optimistic technology which is applicable for the retrieval and reduction of heavy metals in water and polluted lands. Microorganism plays an essential part in bioremediation of heavy metals. By using genetic engineering, genetically modified organisms can be generated which can likely reduce different types of polycyclichydrocarbons (PAHs). Flavobacterium, Pseudomonas, Bacillus, Arthrobacter, Corynebacterium, Methosinus, Rhodococcus, Mycobacterium, Stereum hirsutum, Nocardia, Methanogens, Aspergilus niger, Pleurotus ostreatus, Rhizopus arrhizus, Azotobacter, Alcaligenes, Phormidium valderium, Ganoderma applantus are some microbial species that help in bioremediation of heavy metals. This review not only discussed about the importance of microbes for bioremediation of heavy metals but also discussed about the challenges and limitations of native and engineered bacteria for bioremediation. Significance of bioremediation with the help of genetically engineered bacteria is in light because of its eco-friendly nature and minimum health hazards other than the physio-chemical dependent strategies, which are less eco friendly and dangerous to life.

223 citations