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Discussion with Kenneth Yongabi (CM) et al.
Submitted by IOBB Editor on Thu, 04/05/2006 - 14:52. Biodegradation of
Lubricating oil contaminated soil (08-31 May)
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This forum space is for the discussions with Mr. Kenneth Yongabi
(Cameroon) et al and on their paper Potentials of Pleurotus ostreatus
and urea as Bio Catalysts in the Biodegradation of Lubricating oil
contaminated soil
For any other topics, please use "Speakers Corner" or another existing
forum topic that maybe appropriate.
regards
IOBB Editor
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Further reasearch
Submitted by IOBB Admin Paul T on Sun, 07/05/2006 - 12:13.
IOBB Administration Paul Totterdell
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Hello Kenneth,
I enjoyed your paper very much. As you are aware my work with water
involves use of landscape to absorb and degrade pollutants produced by
human activity. A large proportion of these pollutants are
hydrocarbons.
Your results are very encouraging for me. They suggest to me that a
healthy landscape that has freely available nutrients will generate
bacterial activity that can attack, break down and utilise
hydrocarbons in an opportunistic manner.
It would be interesting to see if a mixture of plurotus substrate and
urea give a different result.
It occurs to me that any attempt to clean up large scale spills would
still require a large amount of urea or plurotus substrate. Have you
heard of the theories of diluted mixtures employed by homeopathic
medicine and some horticutural and agricultural practices?.
This involves creating dilutions of either the catalyst or dilutions
of a tincture (tea) made from a succesfully treated soil. In some
reported cases good results seem to have been obtained from dilutions
of 500x and more. That is; dilute 1 lt of the original tincture (tea)
or saturated solution of the catalyst with 1 lt of water, then dilute
this mixture with 2 litres of water and so on until you have carried
out the dilution 500 times giving an astronomical amount of fluid.
Of course for an experiment you could just take 1 lt from every
dilution to use for the next dilution leaving you with successive
dilution mixtures. 1x 2x 3x 4x etc...say up to 10x or 20x dilutions
It would be interesting to see if the bacterial activity and therefore
biodegredation rate drops off as would be expected, with each
dilution. If It didnt that would be suggestive.
Regards
Paul T
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Interesting gradients in results
Submitted by IOBB Admin Paul T on Sun, 07/05/2006 - 12:29.
IOBB Administration Paul Totterdell
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Hello again Kenneth,
My regards to your fellow researchers.
The even gradient of your results through time and ratio of catalyst
to sample is very interesting. There also seems to be several
threshold points of activity.
The difference in biodegredation rates between 40g of catalyst and
50g, is much larger than that between 50g and 60g.
This suggests an optimum ratio of some kind.
There seems also to be a time threshold where activity at between two
and three weeks is far greater than at any other time. What may be
causing this?
Regards
PaulT
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Interesting gradients in results
Submitted by Kenneth-Yongabi... on Sun, 07/05/2006 - 18:29.
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Dear Paul T,
Thank you for your comments as usual.I think a number of factors may
be intrinsically responsible for the greater results observed with 4o
grams to 50g than with 50 to 60,but the most preferred reason is that
the bacterial flora responsible for the break down must have been at
their exponential phase,rapid multiplication and have now adapted some
sort of at between 50 to 60grams of biocatalyst.
I will be available tomorrow,thanks once more Paul,
Kenneth
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Further reasearch
Submitted by Kenneth-Yongabi... on Wed, 10/05/2006 - 13:28.
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Paul T commented;
it would be interesting to see if a mixture of plurotus substrate and
urea give a different result.
Yes, Paul,the effect is great.I left that bit out for a later
discussion.
It occurs to me that any attempt to clean up large scale spills would
still require a large amount of urea or plurotus substrate. Have you
heard of the theories of diluted mixtures employed by homeopathic
medicine and some horticutural and agricultural practices?.
It sounds intersting Paul,i am not really familiar with such theories
but familair a bit with homeopathic medicine.
your suggestion for further study is very much in place especially if
it warrants large scale treatment of huge contaminated soil.
Your comments are very useful,
Kenneth
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level of lubricating oil in the contaminated soil
Submitted by Jacky Foo on Sat, 13/05/2006 - 17:01.
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Yongabi et al wrote in their paper
>After seven weeks,......application of 60g of spent substrate of
>Pleurotus ostreatus or urea into the lubricating oil - contaminated
>soil, the residual lube oil concentration dropped from 960 mg/g to
>27 mg/g and 960 mg/g to 0.9 mg/g respectively.
In your paper, the units used for "the level of lubricating oil in the
contaminated soil" were :
960mg/L (in abstract)
960mg/g (in Results and Discussion)
the difference between the two is about 1000 times (if 1 L of soil
weighs 1000 g) ????
you wrote:
>Four hundred grammes (400) of lubricating oil contaminated soil were
>introduced each into four plastic containers.
what was the volume or weight of the soil in each plastic bag ?
At a site where there is a spill of lubricating oil on soil (e.g.
car/mechanic workshop) what would be the range/level of lubricating
oil in the contaminated soil ?
Are we dealing with 400 ml of oil in 1 liter of soil or as much as
1000 ml in 1 litre of soil ?
-----
Jacky Foo
http://www.iobbnet.org
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untreated soil - natural microflora
Submitted by Jacky Foo on Sat, 13/05/2006 - 17:07.
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In the abstract:
>After seven weeks, the amount of lubricating oil in untreated soil
(not
>amended) with urea nor Pleurotus ostreatus compost) fell from 960mg/L
>to 282 mg/L. On application of 60g of spent substrate of Pleurotus
>ostreatus or urea into the lubricating oil - contaminated soil, the
>residual lube oil concentration dropped from 960 mg/g to 27 mg/g and
>960 mg/g to 0.9 mg/g respectively
Hi Kenneth
did you have a chance to measure the time (weeks) needed for untreated
soil to reach oil concentration of the levels as achieved with
Pleurotus ostreatus (960 mg/g) or urea (0.9 mg/g) ?
if not, what would be your guess -- 17 weeks ?
-----
Jacky Foo
http://www.iobbnet.org
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nitrogen content in urea and spent substrate
Submitted by Jacky Foo on Sat, 13/05/2006 - 17:18.
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from Yongabi et al's paper:
>To cap it all, take home lessons from this preliminary study are:
>1) Using nutrients such as urea or spent substrate of Pleurotus
>ostreatus as amendments in soil contaminated with oil can increase
>biodegradation of oils - faster clean up! This could be comparatively
>cheaper than always trying to use and depend on pure cultures.
>2) Urea is a better catalyst for the decontamination of
>lubricating oil contaminated soil than spent compost of Pleurotus
>ostreatus.
Q: is this because urea has higher nitrogen content ?
Q: did you measure the N content in the spent substrate ?
Q: If the amount of urea or spent substrate is added on the basis of
the total nitrogen content, would the rate of decontamination be the
same ?
-----
Jacky Foo
http://www.iobbnet.org
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Clean-up Standards - Hydrocarbon Contaminated Soil
Submitted by Jacky Foo on Sat, 13/05/2006 - 17:40.
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I found this on the web:
Pennsylvania Clean-up Standards for Hydrocarbon Contaminated Soil
the units used is mg of hydrocarbon per kg of soil
see section on "No. 4,5,6 Fuel Oil, Lubricating Oil & Fluids"
>Extraction of lubricating oil from soil samples.
>
>After each week fifty grammes of the lubricating oil contaminated
>soil was taken and 250mls of hexane was added, shaken vigorously and
>allowed to stand in a tight fitting glass bottle. This was followed
>by gravity filtration using whatman filter paper. The oil-hexane
>extract was exposed in the sun for 5 days for the hexane to
>evaporate.
I dont fully understand the method of measurement.
You expose the extract in the sun for 5 days and then you measure the
absorbance.
Q: how do you keep the extract sterile during the 5 days ?
Q: after exposure in the sun for 5 days, is there a reduction in the
volume of the extract ?
Q: what else would hexane extract from the soil - apart from the
lubricating oil ?
Q: is there any colour in the extract ?
-----
Jacky Foo
http://www.iobbnet.org
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Phytoremediation of Contaminated Soil
Submitted by Jacky Foo on Sat, 13/05/2006 - 18:05.
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In Environmental Engineering Science (Mar 2004, Vol. 21, No. 2:
157-168, there is an abstract of a paper by
Phytoremediation of Soil Contaminated with Used Motor Oil: I. Enhanced
Microbial Activities from Laboratory and Growth Chamber Studies
Elena Dominguez-Rosado & John Pichtel (Ball State University, Natural
Resources and Environmental Management, Muncie, IN 47306).
>Bacteria were the most abundant microbial group in oil-contaminated
>soil (factor 10 to the power of 8 (10//8) compared to actinomycetes
>and fungi (10//7 and 10//6, respectively). Soil microbial populations
>experienced exponential growth until 50 days, after which numbers
>returned to precontamination levels.
Kenneth:
you work also noted very high bacterial cfu.
In Environmental Engineering Science (Mar 2004, Vol. 21, No. 2:
169-180) Phytoremediation of Soil Contaminated with Used Motor Oil:
II. Greenhouse Studies, Elena Dominguez-Rosado & John Pichtel reported
that
>After 150 days in the clover treatment, the added oil was no longer
>detected.
Kenneth:
could you comment on why you are able to achieve significant
decomtamination in 49 days while phyto-treatment is taking longer ?
-----
Jacky Foo
http://www.iobbnet.org
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Phytoremediation of Contaminated Soil
Submitted by Kenneth-Yongabi... on Sat, 13/05/2006 - 18:48.
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Jacky asked:
>-Kenneth:
>could you comment on why you are able to achieve significant
>decomtamination in 49 days while phyto-treatment is taking longer ?-
The phenomenon on what is happening is simple.
The level of organic matter particularly the high nitrogen from urea
makes a strong nutritional base for bacterial growth and rapid
multiplication. When you multiply nitrogen by 6.25 factor you make
protein and protein is essential for microbial growth and the higher
it is the better the growth. The combination of the oil components
also provides a great carbon source, the lipids concentration with the
high protein source generates a high level of lipo proteins that may
be lower with the use of plant based materials. Lipoprotein is very
essential for building the bacterial cell wall. With such a great
amount of these nutrients for the microbes the rate of metabolism in
the various biochemical pathways goes faster. The spent of Pleurotus
ostreatus is fairly rich in nitrogen as well as some amino acids,
minerals etc as well as scraps/remnants of mycelia rich in enzymes,
this- mix-and in and quantity are possibly lacking with phyto-agent
and the plant materials would have to under go a fermentation process
to generate these rich materials in greater amounts.
Regards,
Kenneth
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Clean-up Standards - Hydrocarbon Contaminated Soil
Submitted by Kenneth-Yongabi... on Sat, 13/05/2006 - 18:57.
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Jacky asked:
>Extraction of lubricating oil from soil samples.
>
>After each week fifty grammes of the lubricating oil contaminated
>soil was taken and 250mls of hexane was added, shaken vigorously and
>allowed to stand in a tight fitting glass bottle. This was followed
>by gravity filtration using whatman filter paper. The oil-hexane
>extract was exposed in the sun for 5 days for the hexane to
>evaporate.
>
>I dont fully understand the method of measurement.
Certainly Jacky, I wouldn't have expected you or many to fully
understand this.
I am employing STANDARD ORGANIC CHEMISTRY EXTRACTION technics to defat
the soil. Hexane is a non polar solvent that defats, that means it
extracts oils which are non polar. This is an innovation that I am
using in environmental studies. As a volatile solvents, once it has
extracted the oil you allow it to evaporate in to air leaving the
oils, then you can go on with whatever you intend to do with the oils.
This is the method of extraction of essential oils from plant
materials.
Regards,
Kenneth
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Clean-up Standards - Hydrocarbon Contaminated Soil
Submitted by Kenneth-Yongabi... on Sat, 13/05/2006 - 19:10.
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>Q: how do you keep the extract sterile during the 5 days ?
This is certainly not an experiment you worry about aseptic
conditions, we are not using it to test as a drug. The whole work is a
pilot-in the field, in the open we only wanted to estimate the
possible quantity of the oils in situ in the contaminated soil. Our
end desire is this, was the oil cleaned up? Back to the soil
contaminated by this oil, bacterial doesn't easily grow either.
>Q: after exposure in the sun for 5 days, is there a reduction in the
>volume of the extract ?
Normally after extraction we have extract-solvent mix, after
evaporation we have the recovered extract - we call it crude extract
recovery, the volume of extract can only reduce if extract does
contain volatile oils/components-in this case I am not sure!
>Q: what else would hexane extract from the soil - apart from the
>lubricating oil ?
I think I have answered this above, Hexane is non polar and ONLY
extracts NON POLAR Materials - OILS
>Q: is there any colour in the extract ?
Pale Yellow or AMBER!
Regards,
Kenneth
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