Subject: Re: E.coli

From: Elaine Ingham <[email-masked]>
Date: Mon, 4 Nov 2002 05:22:40 EST

Ok, let's go over this again.

E. coli out-competes other organisms only in reduced oxygen conditions.  If
E. coli actually could out-compete aerobic organisms, then it would NOT be
useful as an indicator of human pathogens.  Human pathogens require the
conditions in human digestive systems in order to grow - lack of oxygen is
important.  Can you grow Salmonella aerobically?  Sure, in the lab.  But for
Salmonella to survive and grow in food, to give food poisoning problems, the
temperature of the food has to be warm enough, but not too warm, which means
oxygen in the food is limited AND competing organisms are limited.

PLEASE, understand that microbiologists are missing the point when they say
that E. coli can grow aerobically.  It does happen, but ONLY IF competing
aerobic organisms are not present.  Very particular growth conditions are
required.  You must select against the growth of other aerobic organisms.
So, in the lab, the right temperature, rich medium, often antibiotics, and NO
SIGNIFICANT NUMBERS OF COMPETING BACTERIA are all required to grow E. coli in
fully aerobic conditions.

That's what most laboratory, not-familiar-with-the-real-world,
work-with-only-one-species-at-a-time microbiologists don't understand.
Competition is important in the real world.

If you want, you can ask whoever is saying E. coli grows aerobically where
their scientific data are, and I'll be happy to point out where they are
missing the point.

The head of the composting program at the USDA  in Beltsville visited me once
and mentioned an experience where composted manure was tested and E. coli was
not detected.  They put the compost out into a field, and a few days later
detected E. coli.  This person used that example to say that E.coli can come
back to life in compost.

Really?  Ask the appropriate question:  Were there E. coli in the field soil
BEFORE they added the compost?  No answer to that question when I asked it.
I have never seen that paper published either, although I must admit to not
particularly looking for it.  It may have gotten past reviewers who don't
know much about holistic systems.

Here's another example - We take cultures of E. coli and dump them in soil.
If the soil has a healthy foodweb, you will not detect E. coli in 24 hours.
Ah, but if the soil is not healthy, and lacks good structure, you can detect
E. coli for many days.

It's the NORMAL life that is important.  If there are no competitors, no
consumers, no inhibitors, then E. coli may do ok.

Think about your hands.  Every time you visit the bathroom, you potentially
pick up E. coli.  But you aren't swarming with E. coli.  Washing your hands?
But that's just soap, why would that kill E. coli?  You have lots and lots of
bacteria and some fungi on your skin surfaces, and they compete with, inhibit
and consume E .coli.  Only if you are sick, and something severely disrupts
the foods your skin puts out to feed the beneficial bacteria and fungi, will
E. coli be able to survive, and maybe even grow.

If E. coli survived as well in aerobic conditions as it does in anaerobic, E.
coli would not be useful as an indicator of human pathogens.  What would kill
E. coli in the real world, if it could grow just as well aerobically as it
does in reduced oxygen conditions in your digestive system? E. coli would be
everywhere, but it isn't.

Why?

Elaine Ingham
President, Soil Foodweb Inc.
www.soilfoodweb.com

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From: Klaus Wiegand <[email-masked]>
Date: Mon, 4 Nov 2002 13:45:58 +0100

>PLEASE, understand that microbiologists are missing the point
>when they say that E. coli can grow aerobically.

please understand, that soil scientists are missing the point, when
they say the E. coli cannot grow aerobically.

a) ever heard of escherichia switching to mixed-acid-production
(lactic/butryl/acetic and some others) under aerobic conditions ?
b) ever seen them them grow in tatar (minced meat) in a kitchen,
where mother will not die from asphyxation ?
c) ever wondered, why they grow perfectly well on almost any
growth medium like conkey, mda or pda in petri-dishes with these
nice special knobs on the bottom (for air supply) ?
d) one of the major site of nosocomial infection  (30% of all
infections) are pneumonias. hardly the proclaimed anaerobic
conditions you assume.

general rule of thumb is, that e. coli will survive up to 9 months in
soil contaminated with them by sewage or sewage sludge (agricola
or ovid life science should give appropriate results)

>So, in the lab, the right temperature, rich medium, often
>antibiotics, and NO SIGNIFICANT NUMBERS OF COMPETING
>BACTERIA are all required to grow E. coli in

uhhuhh, we find them quite often in cheap foodstuff (when MBM
was still allowed, we found them regularely in 70% of mixtures
containing MBM)  with the usual aerobic colony counts of 10 ^8 to
10 ^9 / gr - incubation in usual temperature chambers (overgrown in
foodstuff with colony numbers above). simple pretesting by vicam,
our experienced technicians have a success rate of about 90%
counterchecked by serology.

>If you want, you can ask whoever is saying E. coli grows
>aerobically where their scientific data are, and I'll be happy to point out where they are
>missing the point.

done by this mail. questions see above under a) to d)

klaus

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From: Frank Teuton <[email-masked]>
Date: Mon, 4 Nov 2002 13:18:24 -0500

Hi Klaus,

Elaine's point is one you missed completely. She knows that E. coli can grow
under aerobic conditions, but only when suitable competition and predation
is lacking.

Using www.google.com I did a bit of searching for 'E.coli survival soil' and
found some interesting morsels:

www.research.teagasc.ie/vteceurope/S+Gprog/boltonsg.html

" In general, sterile distilled water promoted the survival of the organism.
At 15°C in the laboratory, for example, a 1.5 log10 cfu/ml reduction was
observed after 31 days when the initial inoculum level was 3 log10 cfu/ml.
This contrasts with the disappearance of the organism in farm water after 10
days under the same conditions."

.......

"Wang and Doyle (1998), in studies on the survival of a mixture of five
E.coli O157 strains in municipal, reservoir and lake water, recorded
survival times of approximately 50 to 80 days. Rice et al. (1992) made
similar findings. These contrast with the results reported in this paper,
which suggest the organism declines more rapidly and may be undetectable in
as short a period of time as 7 days. Such inconsistencies in survival data
for E.coli O157 may be due to differing microflora in the water samples. "

Hold onto that thought, Klaus, and consider Elaine's full contention:
[aerobic growth of E.coli] " It does happen, but ONLY IF competing aerobic
organisms are not present."

And:

"Here's another example - We take cultures of E. coli and dump them in soil.
If the soil has a healthy foodweb, you will not detect E. coli in 24 hours.
Ah, but if the soil is not healthy, and lacks good structure, you can detect
E. coli for many days.  "

So, the range for E.coli survival in soils is contingent on the presence or
absence of a healthy foodweb, per Dr Ingham.

It has long been known that unfinished compost can be reinoculated with
pathogens and fecal coliforms and generate regrowth of those organisms.
Finished compost will not support regrowth. The reason for that is that a
competitive microflora is established in finished compost during the
mesophilic ('curing') phase that controls pathogenic organisms.

It has also been known, but only recently demonstrated repeatedly in the
lab, that vermicomposting brings about rapid destruction of bacterial
pathogens and indicators. This happens around room temperature, unlike
thermophilic composting, and involves the remediation of pathogens and
installation of a competitive microflora happening simultaneously. The exact
mechanisms through which Salmonella, E.coli and other such organisms are
destroyed are not thoroughly understood, but the fact that they are
destroyed is well established. Vermicompost will  not support pathogen
regrowth.

It thus follows that while a 'compost tea' made from underprocessed manure
containing a substantial population of E.coli might indeed lack the
competitive microflora to inhibit pathogen regrowth, which is one
explanation of the Bess study,
a 'compost tea' made from good vermicompost or compost which has a low E.
coli count to start with, plus the inhibitory microbial consortia present,
can logically be expected to behave as Dr Ingham asserts.

Dr Ingham herself suggests that Bess's study reported faulty DO levels, and
that the system must have dipped into the anaerobic zone for the kind of E.
coli growth she obtained to occur. An alternative explanation is one of
microbial absence, the lack of the competitive organisms needed to control
E. coli.

Bess's study does underscore the need for high quality compost in the making
of compost tea for fresh fruit and produce. She demonstrated at least that a
poor compost in a system that looked, and even measured, as aerobic, was
able to generate E.coli growth when fed certain nutrients.

However, this does not refute Dr Ingham's claim that a good quality compost,
with no or low E.coli counts to start with, would not support E.coli growth
in a properly managed compost tea environment.

Her point, if I understood her well, is that in an anaerobic situation E.
coli growth was quite possible due to the inhibition of the normally
controlling aerobes, but that in an aerobic environment with a full foodweb
present, E. coli will not only not increase, but be substantially reduced.

If you can pull yourself out of your cognitive dissonance and deal with the
assertion that is actually being put forward, perhaps we can get somewhere
with this discussion.

http://www.dmu.ac.uk/~jamesa/learning/dissonance.htm

Frank Teuton

----- Original Message -----
From: "Klaus Wiegand" <[email-masked]>
To: <[email-masked]>
Sent: Monday, November 04, 2002 7:45 AM
Subject: Re: [SANET-MG] E.coli

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