SWIM recently related the following fictional story to me, and I thought I'd post it here, for the edification & possible amusement of others:
---------------------------------------------------------- Ok. I have a casing/possible contam problem which I haven't encountered before, and, after long perusal of the FAQs as well as doing several searches, I can't seem to find a definitive answer about.
Please note that my searches became unnecessarily abbreviated due to the search engine for this site being down (global online searches didn't yield dick, unfortunately) - so, it IS entirely possible that, buried somewhere on the site which I just haven't found yet, this specific info exists, and because of that, if any of the mods wish to delete this post as being quite extraneous, that's fine, no offense taken. However, mere minutes prior to the search function disappearing, I was able to locate *some* tangential information that may/may not apply, but it is unclear, at any rate.
[N.B.: I am *NOT* complaining about the search engine being down - hey, the internet is a best-efforts technology, I know ;D ]
I would have waited until the search function is back up, but I would like to know whether this is a serious & difficult-to-eradicate contam which risks other projects if not thrown out ASAP, so here we go?
Some quick background to explain that no, I am not a complete newbie/idiot, and how this came about, and why it strikes me as somewhat mysterious.
Having used cakes for a long period of time, and always having had sufficient yields from them, my contamination ratio has been miniscule: to wit, in my entire time doing forays into mycological endeavours, I have had four (4) contaminations, three of which were due to messing around w/some experimental procedures with some foreign (long story there) clone matter, which I expected a high failure rate in, anyway. Suffice to say, my procedures are *very* sterile, and I have never even had contams set in on weakened/nearly spent cakes, as even their environs is kept rigorously sterile.
Of course, despite having fine yields off of cakes, I figured, well, why not BOOST those with casings ;D
While familiar with the theory behind casing, I'm certainly a casing newbie, and this is my first foray into that particular art. Regardless, I did apply the same rigorous level of sterility procedures to everything involving my recent casing experiments (at least I'd like to think so?)
So here it is (at last!):
I recently created three primitive casings a la Hongus's 'casing for dummies' (with the addition of sterilization of the vermiculite layers, sterilization of the plastic containers, etc. etc.), which leaves me with three just-larger-than sandwich-sized tupperware containers with a bottom layer of verm, a middle layer of crumbled cakes (two per casing, six cakes total) and a thin (~0.5" or less) layer of verm on top. The cakes chosen were the most robust ones I had at the time, 100% fully colonized, and had no visible (or odorous) contams. Additionally, during the sterilization procedures for the raw vermiculite, peroxide was also used; when the verm was rehydrated for the casing, further-diluted 1% peroxide was added, just to be anal-retentive.
Crumbling was done under sterile conditions, and all appeared to be going well; all casings were placed in an incubator, and, when the most aggressive mycelia began poking through at various places, I patched the spots in two of the three casings, wishing to leave the third alone, just to see if more even pinsets would truly result, versus the control.
Casing number one & two were patched; number three was not. All have been kept at incubation temps to promote speedy re-knitting/recovery of the mycelium.
When checking upon them yesterday, I discovered the following: casing one (but not the other two) has a weak but distinctive, and not unpleasant, odor; my initial impression was that of the breath of a diabetes sufferer (e.g., that characteristic ketone/acetone smell) - but sans acridness. After refreshing my nose with clean, sterile air, and sampling the odor again, I would have to say, without a doubt, it smells like bananas. Not rotten bananas: just sweet, fresh bananas.
While familiar with the fresh, pleasant 'mushroomy' aroma which strong, healthy mycelial bodies give off, I am *positive* this was not it; whether the regular, healthy mycelial odor was also present is difficult to say (after confirming just the banana-like odor, I resealed the casing back up & commenced with chemical decontams of myself & the surrounding area - mad paranoia? Perhaps, but some things can be especially virulent & difficult to eradicate, as I am sure many of you know, so the fewer chances, the better).
Synopsis of further symptom list (or lack thereof):
-no discoloration -no other odors -no foreign growth, so far as I can tell.
My initial thoughts were of pseudomonas spp., my immediate association of a 'fruity' odor tending towards that, but while doing a quick if abortive search across the forums, I found the following:
"In general, the apple smell is going to be your Bacillus, a more grape-like odor is often Pseudomonas. Bananas might be a combo?" [Suntzu].
Beyond that, and a few other similar things, I wasn't able to find any further helpful info. Therefore, if anyone reading this can assist, has had experience with this before, knows someone who has, or can point me towards a thread which would definitively answer it, I would sincerely appreciate any/all feedback on it.
If this is (as I fear) P. aeruginosa, I'm pitching it RIGHT the phuque out - for future reference for anyone who doesn't know, that pseudomonas spp. produces some NASTY shite, no doubt about it (IIRC, its primary toxin is ADP ribosylates EF2, which far too similar in action to diphtheria toxin for MY liking?); however, P. aeruginosa also produces pyocyanin and fluorescein, which are blue/green and greenish/yellow, respectively, and the latter fluoresces under UV lighting, as well (I'm going to do the UV test shortly, but wanted to get this post up the moment I could, in the hopes of someone being able to answer).
As there is no discoloration, I have a gut-feeling the UV scan will show nothing, but will post again in this thread the results from it, either way.
As it stands now, I am _reasonably_ certain these will have to be discarded (unless someone can advise otherwise, or give alternatives) so I won't be heartbroken doing so, but I'd really like to get to the bottom of it, to prevent future casing forays from succumbing to the same bit of nasty (if a 'nasty' it is).
I thank anyone in advance for any answers they can make to this post. ----------------------------------------------------------
That was all SWIM told me. Hope someone can help out.

Regards,
~YSJ~
-------------------- "There are no angels unless they are Angels of Death...And I would never again doubt my place among them or lose my resolve to serve in their wild ranks." -T. Ligotti
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