title: Effects of Mn(II) and Fe(II) on microbial removal of arsenic (III).
abstract: OBJECTIVE
  Arsenic contamination in groundwater creates severe health problems in the world. There are many physiochemical and biological methods available for remediation of arsenic from groundwater. Among them, microbial remediation could be taken as one of the least expensive methods, though it takes longer treatment time. The main objective of this research was to study the improvement on remediation by addition of some essential ion salts such as Mn and Fe.
  
  
  METHODS
  Staphylococcus aureus, Bacillus subtilis, Klebsiella oxytoca, and Escherichia coli were taken as model microbes from Dhulikhel, 30 km east from Kathmandu, Nepal.
  
  
  CONCLUSIONS
  Microbes used in this study showed different abilities in their removal of As(III) with and without addition of Mn and Fe salts. The trend of remediation increased with time. S. aureus was found to be the best among the microbes used. It showed almost 100% removal after 48-h culture, both with and without Fe and Mn salts. Rate of removal of As increased with addition of Fe and Mn for all microbes. Removal efficiency was found to increase by about 32% on average after addition of salts in 24-h cultures of S. aureus.
authors.affiliation: School of Science, Kathmandu University, P.O. Box 6250, Kathmandu, Nepal. reenashrestha@yahoo.com
authors.forename: Reena Amatya
authors.initials: RA
authors.lastname: Shrestha
authors.forename: Bimala
authors.initials: B
authors.lastname: Lama
authors.forename: Jarina
authors.initials: J
authors.lastname: Joshi
authors.forename: Mika
authors.initials: M
authors.lastname: Sillanpää
mesh_terms: D000327:Adsorption; D001151:Arsenic / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D001412:Bacillus subtilis / Q000378:metabolism; D001419:Bacteria / Q000378:metabolism*; D002413:Cations, Divalent; D004926:Escherichia coli / Q000378:metabolism; D005374:Filtration; D007501:Iron / Q000737:chemistry*; D041121:Klebsiella oxytoca / Q000378:metabolism; D008345:Manganese / Q000737:chemistry*; D008906:Mining; D013211:Staphylococcus aureus / Q000378:metabolism; D013997:Time Factors; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D018508:Water Purification / Q000379:methods*
chemical_list: D002413:Cations, Divalent; D014874:Water Pollutants, Chemical; D008345:Manganese; D007501:Iron; D001151:Arsenic