Phosphate release and heavy metal accumulation by biofilm-immobilized and chemically-coupled cells of acitrobacter sp. pre-grown in continuous culture

Polyhydroxybutyrate accumulation by a Serratia sp.

“…NCIMB 40259 was grown under licence from Isis Innovation (Oxford) under carbon (lactoselimited) continuous cultivation with ammonium phosphate as the N and P source at 30 o C in an air-lift fermenter as described previously (Finlay et al 1999;Macaskie et al 2005). Cells were obtained in two ways.…”

“…Cells were obtained in two ways. Biofilms were grown on polyurethane reticulated foam cube supports within the vessel lumen (1cm 3 , Filtren TM 30 foam cubes supplied by Recticel, Belgium: Finlay et al 1999;Macaskie et al 2005) or taken from the fermenter outflow at steady-state (planktonic cells). In some experiments a scaled-down fermenter with the same proportional dimensions was used to obtain planktonic cells; the pH and DO 2 profiles of the cultures during growth were similar and cells obtained by the two methods were indistinguishable (Allan, 1999).…”

Effect of nutrient limitation on biofilm formation and phosphatase activity of a Citrobacter sp.

“…NCIMB 40259 was used under licence from Isis Innovation, Oxford, UK. Biofilms were grown under lactose limitation in an air-lift reactor as described by Finlay et al (1999) or, for comparison of growth under carbon, phosphorus or nitrogen limitation, in three parallel scaled-down (tenfold) reactors (working volume of 250 ml each). Dissolved oxygen (dO # ) and temperature (not less than 50 % dO # and 30 mC, respectively) were monitored as previously (Finlay et al, 1999).…”

“…Biofilms were grown under lactose limitation in an air-lift reactor as described by Finlay et al (1999) or, for comparison of growth under carbon, phosphorus or nitrogen limitation, in three parallel scaled-down (tenfold) reactors (working volume of 250 ml each). Dissolved oxygen (dO # ) and temperature (not less than 50 % dO # and 30 mC, respectively) were monitored as previously (Finlay et al, 1999). For subsequent analyses using scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) glass cover slips (22i64 mm ; Chance Propper) were suspended via silicone sealant in the ' down-flow ' side of the reactor on a purpose-built silicone tubing support (Finlay et al, 1999).…”

“…(NCIMB 40259) has been used for the bioremediation of heavy metals via the activity of an acid-type phosphatase enzyme (Jeong & Macaskie, 1999) which liberates HPO# − % from a suitable organic phosphate donor with the stoichiometric precipitation of metal cations (M# + ) as insoluble MHPO % at the cell surface (Macaskie et al, 1995 ;Finlay et al, 1999). Conditions promoting maximum biofilm growth may not necessarily produce maximum enzymic activity.…”