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- Bodlund, Ida, 1983-
(författare)
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Coagulant Protein from plant materials: Potential Water Treatment Agent
- 2013
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Access to fresh water is a human right, yet more than 780 million people, especially in rural areas, rely on unimproved sources and the need for finding ways of treating water is crucial. Although the use of natural coagulant protein in drinking water treatment has been discussed for a long time, the method is still not in practice, probably due to availability of material and limited knowledge. In this study, about hundred different crude extracts made from plant materials found in Southern India were screened for coagulation activity. Extracts of three Brassica species (Mustard, Cabbage and Cauliflower) were showing activity comparable to that of Moringa oleifera and were further investigated. Their protein content and profile were compared against each other and with coagulant protein from Moringa. Mustard (large) and Moringa seed proteins were also studied for their effect against clinically isolated bacterial strains. The protein profiles of Brassica extract showed predominant bands around 9kDa and 6.5kDa by SDS-PAGE. The peptide sequence analysis of Mustard large identified the 6.5kDa protein as Moringa coagulant protein (MO2.1) and the 9kDa protein band as seed storage protein napin3. Of thirteen clinical strains analysed, Moringa and Mustard large were proven effective in either aggregation activity or growth kinetic method or both in all thirteen and nine strains respectively. To my knowledge this is the first report on the presence of coagulant protein in Brassica seeds. Owing to the promising results Brassica species could possibly be used as a substitute to Moringa coagulating agent and chemicals in drinking water treatment.
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| 2. |
- Lakshmanan, Ramnath, 1987-
(författare)
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Application of magnetic nanoparticles and reactive filter materials for wastewater treatment
- 2013
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Lately sewage wastewater treatment processes (WWTP) are facing challenges due to strict regulations in quality of effluent standards and waste production. The reuse of wastewater treatment effluents is rapidly gaining attention as a means of achieving sustainable water supply. Therefore, new methods are required to achieve an efficient WWTP. The foremost emphasis of the present study is to investigate filter materials, synthesis, characterization, and application of magnetic nanoparticles (NPs) for WWTP. Primarily commercially available reactive filter materials such as Polonite and Sorbulite were tested for the effective reduction of contaminants in recirculation batch mode system. Secondly, the magnetic nanoparticles were synthesized using different techniques such as water-in-oil (w/o) microemulsion and co- precipitation methods and testing for their ability to remove contaminants from wastewater. Thirdly, toxicity test of magnetic NPs were performed using human keratinocytes (HaCaT) and endothelial (HMEC-1) cells (Papers I-VII).The magnetic iron oxide nanoparticles (MION) synthesized using the co-precipitation method were further functionalized with tri-sodium citrate (TSC), 3-aminopropyl triethoxysilane (APTES), polyethylenimine (PEI) and chitosan. The functionalized MION were further characterized prior to use in removal of contaminants from wastewater. The sewage wastewater samples were collected from Hammarby Sjöstadsverk, Sweden and analyses were performed for the reduction of turbidity, color, total nitrogen, total organic carbon, phosphate and microbial content on the retrieval day.The experimental results imply that Polonite and Sorbulite require high pH for the efficient reduction of phosphate and the reduction of microbes. Microemulsion prepared magnetic nanoparticles (ME-MION) showed ≈100% removal of phosphate in 20 minutes. Results from TEM implied that the size of magnetic Nps were around 8 nm for core (uncoated MION), TSC (11.5 nm), APTES (20 nm), PEI (11.8 nm) and chitosan (15 nm). Optimization studies using central composite face centered (CCF) design showed the potential of magnetic nanoparticles for the removal of turbidity (≈83%) and total nitrogen (≈33%) in 60 minutes. The sludge water content was reduced significantly by ≈87% when magnetic NPs were used whilst compared to the chemical precipitant used in WWTP. PEI coated MION showed ≈50% removal of total organic carbon from wastewater in 60 minutes. Effluents from wastewater treated with magnetic NPs were comparable with effluent from the present WWTP. There was no significant change observed in mineral ion concentration before and after treatment with MION. In addition, toxicity results from HMEC-1 and HaCaT cells revealed no formation of reactive oxygen species in the presence of magnetic NPs. Furthermore, laboratory experiments revealed the effectiveness and reusability of magnetic NPs. Thus magnetic NPs are a potential wastewater treatment agent and can be used for effective removal of contaminants, thereby reducing the process time, sludge water content and complex process steps involved in conventional WWTP.
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