The chromium reduction carried out between 16 and 24 hours under the sulfatereducing process. The measuring of chromium in liquid phase and biofilm indicated
a deficit of chromium added to culture medium; see Fig. 13.8. The remaining
chromium was localized in the free biomass, this was reveled by a TEM analysis
when evaluate the accumulation of chromium in the cells. The micrographs obtained
from D. alaskensis strain 6SR were not stained when chromium was present,
whereas cells not exposed to the metal were stained with lead citrate. Comparison
of both micrographs showed an accumulation of chromium on extern and cellular
membrane and periplasmic space in the cell; see Fig. 13.9. For this reason, the
chromium removal follows a precipitation by chromium sulfide and
bioaccumulation in the biofilm and cellular surface.
D es u lf o v ib ri o m a g n e ti c u s R S -1
D e su lf o vi b ri o v u lg a ri s
D es u lf o vi b ri o sp .
D es u lf o v ib ri o d e su lf u ri ca n s
D es u lf o vi b ri o a la sk en si s 6 S R
R h o d o vo lu m
T h io b a c il lu s fe rr o o x id a n s
R h o d o b a ct e r sp h a e ro id es
E sc h er ic h ia c o li b io fi lm
A zo m o n a s a g il is P Y 1 0 1
G e o b a c il lu s st e a ro th e rm o p h il u s
S ta p h y lo c o cc u s x yl o su s
R h o d o co c u s o p a cu s
S p h in g o m o n a s p a u ci m o b il is (E P S )
C lo st ri d iu m th e rn o a ce ti c u m
A sp er g il lu s n ig er
C h lo re ll a vu lg a ri s
C a rb o n , g ra n u la r a c ti v a te d
Percentage of removal (% )
0
20
40
60
80
100
0
20
40
60
80
100
120
140
160
180
Gram negative
Gram
positive
Others
Removal of Cadmium (mg/L)
Fig. 13.4 Removal of cadmium obtained among Desulfovibrio alaskensis 6SR and other
microorganisms. The graphic was made using data previously reported (Arakaki et al. 2002;
Cunningham and Lundie 1993; Yun-guo et al. 2006; Quintelas et al. 2009; Selatnia et al. 2004;
Sinha and Mukherjee 2009; Vásquez et al. 2007; Watanabe et al. 2003; White and Gadd 1998;
Ziagova et al. 2007)
382
M. I. Neria-González and R. Aguilar-López
a deficit of chromium added to culture medium; see Fig. 13.8. The remaining
chromium was localized in the free biomass, this was reveled by a TEM analysis
when evaluate the accumulation of chromium in the cells. The micrographs obtained
from D. alaskensis strain 6SR were not stained when chromium was present,
whereas cells not exposed to the metal were stained with lead citrate. Comparison
of both micrographs showed an accumulation of chromium on extern and cellular
membrane and periplasmic space in the cell; see Fig. 13.9. For this reason, the
chromium removal follows a precipitation by chromium sulfide and
bioaccumulation in the biofilm and cellular surface.
D es u lf o v ib ri o m a g n e ti c u s R S -1
D e su lf o vi b ri o v u lg a ri s
D es u lf o vi b ri o sp .
D es u lf o v ib ri o d e su lf u ri ca n s
D es u lf o vi b ri o a la sk en si s 6 S R
R h o d o vo lu m
T h io b a c il lu s fe rr o o x id a n s
R h o d o b a ct e r sp h a e ro id es
E sc h er ic h ia c o li b io fi lm
A zo m o n a s a g il is P Y 1 0 1
G e o b a c il lu s st e a ro th e rm o p h il u s
S ta p h y lo c o cc u s x yl o su s
R h o d o co c u s o p a cu s
S p h in g o m o n a s p a u ci m o b il is (E P S )
C lo st ri d iu m th e rn o a ce ti c u m
A sp er g il lu s n ig er
C h lo re ll a vu lg a ri s
C a rb o n , g ra n u la r a c ti v a te d
Percentage of removal (% )
0
20
40
60
80
100
0
20
40
60
80
100
120
140
160
180
Gram negative
Gram
positive
Others
Removal of Cadmium (mg/L)
Fig. 13.4 Removal of cadmium obtained among Desulfovibrio alaskensis 6SR and other
microorganisms. The graphic was made using data previously reported (Arakaki et al. 2002;
Cunningham and Lundie 1993; Yun-guo et al. 2006; Quintelas et al. 2009; Selatnia et al. 2004;
Sinha and Mukherjee 2009; Vásquez et al. 2007; Watanabe et al. 2003; White and Gadd 1998;
Ziagova et al. 2007)
382
M. I. Neria-González and R. Aguilar-López