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Anno
Experimenter



Registered: 06/17/99
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Re: Culture storage technique [Re: YidakiMan]
#2975898 - 08/07/04 03:54 PM (20 years, 6 months ago) |
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>Does the 1.5% agar solution solidify?
Yes.
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Anno
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Re: Culture storage technique [Re: fastfred]
#2975941 - 08/07/04 04:10 PM (20 years, 6 months ago) |
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>dH2O is not a very good storage medium. Besides containing no nutrients the >dH2O will suck out the nutrients from the mycelium. >The end result: Death by osmosis.
Osmosis doesn't work this way. It actually works exactly the opposite way. Water flows from the area with the lower concentration of ions(distilled water) to the area with the higher concentration of ions(a cell). Not the other way round.
And, this method works, as the numerous experiments that have been made clearly show.
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RogerRabbit
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Re: Culture storage technique [Re: Anno]
#2976051 - 08/07/04 04:51 PM (20 years, 6 months ago) |
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Interesting stuff guys, thanks. I've lost a few cultures in test tubes after a year or more, and petri dishes are no good at all for long term storage.
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fastfred
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Registered: 05/17/04
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Re: Culture storage technique [Re: Anno]
#2976290 - 08/07/04 06:14 PM (20 years, 6 months ago) |
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Quote:
Osmosis doesn't work this way. It actually works exactly the opposite way. Water flows from the area with the lower concentration of ions(distilled water) to the area with the higher concentration of ions(a cell). Not the other way round.
I'm not referring to the water, but rather the minerals in the water. Putting anything into distilled water will leach out most of the minerals it contains. Fish can't live in distilled water, mainly because of this.
Quote:
And, this method works, as the numerous experiments that have been made clearly show.
Perhaps I should have read the thread a little more carefully before I responded. I was quite confident of my explanation because it was explained to me that way by a mycology professor. His observations are probably based on dddi water. The papers referenced above are based on your basic distilled water which probably still contains enough ions to avoid killing the mycelium.
My main point was (or should have been) that it would be much better to use mineral water rather than distilled water.
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Anno
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Re: Culture storage technique [Re: fastfred]
#2977673 - 08/08/04 07:45 AM (20 years, 6 months ago) |
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>Putting anything into distilled water will leach out most of the minerals it contains.
This doesn't happen. Any substances in the mycelium are contained within cells. Each cell has a membrane. Due to osmosis, if anything water will get into the cell and stay there, it is not like water is flowing passively in and out and washes out anything from the cells. Nature doesn't work this way.
>Fish can't live in distilled water, mainly because of this.
I don't know if the can or if they can't, I haven't found any direct references on this. I never tried an put a fish in distilled water.
Fish have a water management system depending on in what water they live.
Fish living in salt water constantly have to drink salt water in order to compensate the water loss through osmosis , since the concentration of the minerals in the water is much higher than in the body, thus the water is flowing from the body into the sea.
Fish living in normal water constantly have to excrete large amounts of water through kidneys in order to compensate the water gain through osmosis, since the concentration of the minerals in the fish is much higher than in the water , thus the water is flowing into the body of the fish.
The question if fish survive in distilled water is an interesting one and might be worth a trial.
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fastfred
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Registered: 05/17/04
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Re: Culture storage technique [Re: Anno]
#2977705 - 08/08/04 08:10 AM (20 years, 6 months ago) |
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I've never put a fish in distilled water, but I have seen it on the internet.
Concentrations of ions will move from the area of greater concentration towards the area of lower concentration. That's why I wouldn't use distilled water.
Just becasue something can survive in it doesn't mean it's optimal.
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Anno
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Re: Culture storage technique [Re: fastfred]
#2977710 - 08/08/04 08:16 AM (20 years, 6 months ago) |
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>Concentrations of ions will move from the area of greater concentration towards >the area of lower concentration.
You are talking of diffusion. In this case ye, this is how diffusion works.
When a cell which has a membrane comes into play, you no longer have a simple diffusion, but osmosis. And this is when the statement "Concentrations of ions will move from the area of greater concentration towards the area of lower concentration" isn't true anymore.
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fastfred
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Re: Culture storage technique [Re: Anno]
#2977752 - 08/08/04 09:07 AM (20 years, 6 months ago) |
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Biological membranes can only maintain a certain gradient across the membrane. By putting distilled water on one side you have just created a gradient that never occurs in nature. Cells can't maintain that steep of a gradient.
That may explain why it creates a state of suspended animation. But, I hardly think it's healthful for the mycelium though.
In any case, depending on the method you use, you're probably introducing enough media and/or mycelium to provide the necessary minerals. Hence it's not really distilled water anymore.
Is there any reason *not* to use normal water which has a much more natural composition?
Distilled water tastes like shit... That's enough reason for me not to use it.
I pulled this quote from a website... I haven't checked it's accuracy.
According to the U.S. Environmental Protection Agency, "Distilled water, being essentially mineral-free, is very aggressive, in that it tends to dissolve substances with which it is in contact. Notably, carbon dioxide from the air is rapidly absorbed, making the water acidic and even more aggressive. Many metals are dissolved by distilled water."
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Anno
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Re: Culture storage technique [Re: fastfred]
#2977942 - 08/08/04 10:39 AM (20 years, 6 months ago) |
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>According to the U.S. Environmental Protection Agency
I tried to find this statement in at their website, www.epa.gov to no avail.
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fastfred
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Re: Culture storage technique [Re: Anno]
#2977992 - 08/08/04 10:51 AM (20 years, 6 months ago) |
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It could be bogus... Didn't make it up myself though.
Anyway, has anyone tried a comparison between media vs dH20 vs H2O?
I would assume that the media would have a very definite lifespan since a FOAF has seen ME jars go bad within 7 months at room temp.
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Suntzu
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Re: Culture storage technique [Re: Anno]
#2978107 - 08/08/04 11:39 AM (20 years, 6 months ago) |
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found it here: [a few paragraphs down]. Not the original source, but appears to be the above quote from the EPA.
http://www.mercola.com/article/water/distilled_water.htm.
Edited by Suntzu (08/08/04 12:08 PM)
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Anno
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Re: Culture storage technique [Re: Suntzu]
#2978114 - 08/08/04 11:42 AM (20 years, 6 months ago) |
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I know, the quote is all around the web, but the source doesn't have it....
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Suntzu
Geek


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Re: Culture storage technique [Re: Anno]
#2978168 - 08/08/04 12:08 PM (20 years, 6 months ago) |
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Hmmm. . .I couldn't find anything directly from the EPA, either. It's possibly a fabrication? ? My main man, Dr. Weil has a few things to say about the 'death by distilled water' websites:
http://www.drweil.com/app/cda/drw_cda.html-command=TodayQA-questionId=21181
I've used dH2O for a few years now, it does work. I've been using double-distilled ultra filtered water; specifically to produce water free of ions/metals for molecular bio work. One thing for sure, the pH of this water can drop; Adding a generous helping of mycelium actually brings it back up! [over time]. With any storage technique, a percentage of cells will die. Even the textbook '15% glycerol/PBS in -80C' kills a number of the cells. All you need is a decent number of them to survive and the storage technique was successful.
Honestly, I can see regular water working just fine, as long as it's sterilized and non-nutritive. I have thought about experimenting with pH-buffered ETDA solutions, but the straight ddH2O has worked well enough.
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Anno
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Re: Culture storage technique [Re: Suntzu]
#2978361 - 08/08/04 01:33 PM (20 years, 6 months ago) |
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I wrote Dr. Mercola an email, perhaps he can provide me with the source of that quotation.
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Speeker

Registered: 02/11/04
Posts: 902
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Re: Culture storage technique [Re: Suntzu]
#3022038 - 08/19/04 03:39 AM (20 years, 6 months ago) |
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Quote:
Of the 151 isolates taken from water storage (after storage up to 7 yr), 94% were viable. For those isolates with previously recorded growth rates, the growth rates were not consistently affected by the distilled water storage method (TABLE I). For those for which previous information was not available, the growth rates were as expected (TABLE I). Thus, water storage did not have an obvious influence on culture viability or growth rate.
--> Preserving cultures of wood-decaying Badidiomycotina using sterile distilled water in cryovials http://www.fpl.fs.fed.us/documnts/pdf1994/burds94a.pdf
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ragadinks
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Re: Culture storage technique [Re: Speeker]
#3022151 - 08/19/04 05:01 AM (20 years, 6 months ago) |
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Great link ! They are storing the cultures together with the agar! It does not seem to be necessary remove all nutrients from the mycelium prior to storage ?
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flameclown
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Re: Culture storage technique *DELETED* [Re: ragadinks]
#3032384 - 08/21/04 11:56 AM (20 years, 5 months ago) |
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Post deleted by flameclownReason for deletion: [this post is damn old]
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fastfred
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Re: Culture storage technique [Re: flameclown]
#3036603 - 08/22/04 03:01 PM (20 years, 5 months ago) |
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Search ebay for "vials" it comes up with a ton of results. You might also try american science and surplus and/or all electronics. Those are both surplus places and sell a lot of stuff fairly cheap.
-FF
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psiloz
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Re: Culture storage technique [Re: Anno]
#3038870 - 08/23/04 08:39 AM (20 years, 5 months ago) |
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Re : fish in distilled water
Should be Ok as the fish gets plenty of salts from the food, theyll also be pumping out Ammonia through their gills so the water wont stay pure for long
Main issue is Acidity
Very soft water ie rainwater has non Ca or Mg salts to buffer it so pH can move swiftly to killing levels
however fish from some upland rainfed water bodies can live in quite soft, low TDS water
Angelfish i think are an example of fish liking soft water
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YidakiMan
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Re: Culture storage technique [Re: flameclown]
#3040531 - 08/23/04 05:48 PM (20 years, 5 months ago) |
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Look for microcentrifugal tubes. They are far cheaper than glass dram vials. At American Science and surplus, 10cents each for a 2ml tube.
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