E
xperiments
were
conducted on
an aqueous growth medium containing
cultures of
Escherichia
c
oli
(
E. coli
)
XL1
-
Blue
,
to investigate
, in a single experiment,
the effect of
two
types of
dynamic
mechanical loading on
cellular integrity
. A bespoke shock tube
was
used to
subject
separate portions of a
planktonic bacteria
l culture
to
two
different
loading sequences:
(i)
shock
compression
followed by cavitation, and (ii
)
shock
compression followed by
spray
.
T
he apparatus allow
s
the
generati
on of
a
n adjustable
lo
a
ding shock
wave of
magnitude
up to
3
00
M
Pa in a sterile laboratory environment. C
ultures
of
E. coli
were
tested
with this
apparatus
and
the
s
pread
-
plate
technique was used
to
measure
the
survivability
after
mechanical loading
.
T
he
loading sequence (ii) gave higher mortality than (i),
suggesting that
the
bacteria
are
more
vulnerable
to shear deformation
and cavitation
than to
hydrostatic
compressi
on
.
We present results of preliminary experi
ments and suggestions for further
experimental work; we discuss the potential applications of this technique to sterilise large
volumes of fluid samples.