Jeanna Starosvetsky

Publications of Jeanna Starosvetsky

• Combined chemical-biological treatment for prevention/rehabilitation of clogged wells by an iron-oxidizing bacterium.

  Authors: Efrat Gino, Jeanna Starosvetsky, Eyal Kurzbaum, Robert Armon

  Environmental science & technology. 03/2010; 44(8):3123-9.

  Groundwater wells containing large concentrations of ferrous iron face serious clogging problems as a result of biotic iron oxidation. Following a short time after their start off, wells get clogged,Groundwater wells containing large concentrations of ferrous iron face serious clogging problems as a result of biotic iron oxidation. Following a short time after their start off, wells get clogged, and their production efficiency drop significantly up to a total obstruction, making cleanup and rehabilitation an economic burden. The present study was undertaken to test an experimental combined treatment (chemical and biological) for future prevention or rehabilitation of clogged wells. Sphaerotilus natans (an iron-oxidizing bacterium) freshly isolated from a deep well was grown to form biofilms on two systems: coupons and sand buried miniature wedge wire screen baskets. A combined chemical-biological treatment, applied at laboratory scale by use of glycolic acid (2%) and isolated bacteriophages against Sphaerotilus natans (SN1 and ER1-a newly isolated phage) at low multiplicity of infection (MOI), showed inhibition of biofilm formation and inactivation of the contaminant bacteria. In addition to complete inactivation of S. natans planktonic bacteria by the respective phages, earlier biofilm treatment with reduced glycolic acid concentration revealed efficient exopolysaccharide (EPS) digestion allowing phages to be increasingly efficient against biofilm matrix bacteria. Utilization of this combined treatment revealed clean surfaces of a model stainless steel wedge wire screen baskets (commonly used in wells) for up to 60 days.

• Whole cell imprinting in sol-gel thin films for bacterial recognition in liquids: macromolecular fingerprinting.

  Authors: Tally Cohen, Jeanna Starosvetsky, Uta Cheruti, Robert Armon

  International journal of molecular sciences. 01/2010; 11(4):1236-52.

  Thin films of organically modified silica (ORMOSILS) produced by a sol-gel method were imprinted with whole cells of a variety of microorganisms in order to develop an easy and specific probe toThin films of organically modified silica (ORMOSILS) produced by a sol-gel method were imprinted with whole cells of a variety of microorganisms in order to develop an easy and specific probe to concentrate and specifically identify these microorganisms in liquids (e.g., water). Microorganisms with various morphology and outer surface components were imprinted into thin sol-gel films. Adsorption of target microorganism onto imprinted films was facilitated by these macromolecular fingerprints as revealed by various microscopical examinations (SEM, AFM, HSEM and CLSM). The imprinted films showed high selectivity toward each of test microorganisms with high adsorption affinity making them excellent candidates for rapid detection of microorganisms from liquids.

• Inhibition of biofilm formation on UF membrane by use of specific bacteriophages

  Authors: Guy Goldman, Jeanna Starosvetsky, Robert Armon

  Journal of Membrane Science.

  A model ultrafiltration (UF) continuous recycled system fed with previously sterilized effluents (two sources) was experimentally inoculated with three bacterial species: Pseudomonas aeruginosa,A model ultrafiltration (UF) continuous recycled system fed with previously sterilized effluents (two sources) was experimentally inoculated with three bacterial species: Pseudomonas aeruginosa, Acinetobacter johnsonii and Bacillus subtilis (separately and combined). Subsequently, the corresponding specific lytic bacteriophages were supplemented versus control (bacteria without phages) and the experimental set-up was operated for >80 h. The seeded phages lytic activity reduced membrane biofouling by an average of 40% to >60% compared to control. Concentrate phage numbers increased accordingly and some were found in the permeate, however inoculated bacteria were not found in the permeate. Combinations of one, two and three bacterial species in parallel with their specific phages, revealed significant and efficient inactivation rates as well reduced biofouling as detected with high resolution electron scaning microscope (HSEM) and permeability test. The results suggest on potential use of specific lytic phages to prevent UF membrane biofouling. Additionally, future application of specific bacteriophages concept in other membrane processes such as: nanofiltration and reverse osmosis, that encounter less bacterial species diversity, can be successful.