The morphologies of P. fluorescens cells at different stages of
UVA exposure are shown in Fig. 1. As reaction time increased, the
cell morphologies changed evidently. The control P. fluorescens cell
were rod-shaped and intact (Fig. 1a e P. fluorescens A). The cell
surface was smooth and cell membranes and outer cell walls were
easily identified. After treated for 30 min (Fig. 1a e P. fluorescens B),
parts of the cells were attached by black, solid dots, which are most
likely TiO2 nanoparticles; but bacterial cells still remained intact
and the double lipid membranes were still visible. After 90 min
treatment (Fig. 1a e P. fluorescens C), the outer cell walls were losing
its integrity. Some regions in the cell turned white, maybe due to
formation of holes on cell surfaces. The border of cell membranes
became obscure, especially the parts where black dots were found
or TiO2 nanoparticles were attached to. The cell membranes were
hardly identified. After 150 min, bacterial cells lost both its outer
boundary and parts of its cytoplasm.
The similar development in the cell degradation was also
observed in M. caseolyticus cell morphology during the photocatalytic
treatment (Fig. 1b e M. caseolyticus). The normal untreated
M. caseolyticus cells are shown in Fig. 1b e M. caseolyticus A. The cell
was well circled and surrounded by outside cell wall and cell
membranes. The cell wall was much thicker compared with
P. fluorescens. After treated for 30 min (Fig. 1b e M. caseolyticus B),
the cell wall and cell membranes were still intact; however, they
were not as well defined as the control (Fig. 1b e M. caseolyticus A).
Some parts were attached by black particles. After 90 min, the cell
wall and membranes were damaged and cytoplasm leaked out
The morphologies of P. fluorescens cells at different stages of
UVA exposure are shown in Fig. 1. As reaction time increased, the
cell morphologies changed evidently. The control P. fluorescens cell
were rod-shaped and intact (Fig. 1a e P. fluorescens A). The cell
surface was smooth and cell membranes and outer cell walls were
easily identified. After treated for 30 min (Fig. 1a e P. fluorescens B),
parts of the cells were attached by black, solid dots, which are most
likely TiO2 nanoparticles; but bacterial cells still remained intact
and the double lipid membranes were still visible. After 90 min
treatment (Fig. 1a e P. fluorescens C), the outer cell walls were losing
its integrity. Some regions in the cell turned white, maybe due to
formation of holes on cell surfaces. The border of cell membranes
became obscure, especially the parts where black dots were found
or TiO2 nanoparticles were attached to. The cell membranes were
hardly identified. After 150 min, bacterial cells lost both its outer
boundary and parts of its cytoplasm.
The similar development in the cell degradation was also
observed in M. caseolyticus cell morphology during the photocatalytic
treatment (Fig. 1b e M. caseolyticus). The normal untreated
M. caseolyticus cells are shown in Fig. 1b e M. caseolyticus A. The cell
was well circled and surrounded by outside cell wall and cell
membranes. The cell wall was much thicker compared with
P. fluorescens. After treated for 30 min (Fig. 1b e M. caseolyticus B),
the cell wall and cell membranes were still intact; however, they
were not as well defined as the control (Fig. 1b e M. caseolyticus A).
Some parts were attached by black particles. After 90 min, the cell
wall and membranes were damaged and cytoplasm leaked out
การแปล กรุณารอสักครู่..
