Simultaneous oxidation and immobilization of arsenite from refinery waste water by thermoacidophilic iron-oxidizing archaeon, Acidianus brierleyi

Speciation of arsenic in a thermoacidophilic iron-oxidizing archaeon, Acidianus brierleyi, and its culture medium by inductively coupled plasma–optical emission spectroscopy combined with flow injection pretreatment using an anion-exchange mini-column

“…However, As(III) was only weakly toxic, since the A. brierleyi culture was still alive even after 14-days incubation although a gradual decrease in the number of cells was observed [12].…”

“…All solutions were prepared by being dissolved in water that had been purified by means of an ultrapure MILLI-Q system (Millipore, Molsheim, France). The microorganisms used in this study, A. brierleyi (DSMZ 1651), were cultured in the same manner as that reported in a previous paper [12,13]. Briefly, A. brierleyi was cultured in a 500 mL…”

“…Under these conditions, the number of cells was observed to decrease [12], which was attributed to both a lack of an energy source and the toxicity of As(III) to A. brierleyi. However, As(III) was only weakly toxic, since the A. brierleyi culture was still alive even after 14-days incubation although a gradual decrease in the number of cells was observed [12].…”

“…A. brierleyi can oxidize Fe(II) to Fe(III) in its growth process, whereas the rate of the redox reaction between Fe(III) and 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 11 oxidize As(III) to As(V), according to the standard redox potential for Fe(II)/Fe(III) and As(III)/As(V) [17]. Therefore, As(III) should also be oxidized by A. brierleyi, as proposed by Okibe and coworkers [12]. To confirm this simultaneous oxidation, two kinds of culture media containing 500 ppm of As(III) were prepared, one with 900 ppm of Fe(II) and another without Fe(II).…”

“…Acidianus brierleyi [12]. They demonstrated that the microorganism would be useful for the removal of As from the refinery wastewater that is produced in the mining industry, although the details surrounding the oxidation mechanism of A. brierleyi remain unclear.…”