|
Some of these posts are very old and might contain outdated information. You may wish to search for newer posts instead.
|
dusttodust


Registered: 11/26/12
Posts: 491
|
Agar question
#19248787 - 12/09/13 04:49 AM (10 years, 1 month ago) |
|
|
Hi,
I transfered a piece on agar but it was contaminated with bacteria. However, mycelium was faster. Bacteria can only be seen at the center where i put piece .

My question: Can i inoculate a bag with agar wedges that arent contaminated with bacteria? Im referring to outer part of mycelium circle. Im pretty sure that wouldnt be a problem. But i wouldnt want to toss a bag if i learned i was wrong.
|
Sgt. Pepper



Registered: 06/19/13
Posts: 2,538
Loc: Third Stone From The Sun
Last seen: 1 month, 23 days
|
|
If I were you I'd make a transfer to another agar wedge first. If you couldn't though, I don't know much about agar though.
|
NOS4A2
This is the way


Registered: 07/22/04
Posts: 572
Loc: -tite
|
|
If you're certain what you are seeing is a contam and not just the old specimen bruising then I would transfer to three new plates and continue transferring until you get a specimen which appears pure. Patience is the key. Even if it wasn't a contam I would prolly transfer to 3 new plates any way. In either case you'll have more inoculum for your spawn and it will be pure, a win win.
--------------------
|
Pastywhyte
Say hello to my little friend



Registered: 09/15/12
Posts: 37,810
Loc: Canada
|
Re: Agar question [Re: NOS4A2]
#19248926 - 12/09/13 06:36 AM (10 years, 1 month ago) |
|
|
Yeah IMO its better safe than sorry. Looks to me like your one transfer from a clean plate, why take the risk?
|
dusttodust


Registered: 11/26/12
Posts: 491
|
|
Lol none of you answered my question, all you told me is what i already know.
Im still lookin for someone to verify that clean parts of agar wouldnt pose any problems when inoculating.
|
Pastywhyte
Say hello to my little friend



Registered: 09/15/12
Posts: 37,810
Loc: Canada
|
|
Because no one can be sure that they won't. Rule of thumb is use clean cultures, why would you even want to mess around? Go ahead and try it but if it ends up contamed we told you so.
|
dusttodust


Registered: 11/26/12
Posts: 491
|
|
Im not looking for anyone to guarantee me success, i know thats not in your power.
If i had mold in there i wouldnt be asking this because it spreads everywhere.
But bacteria doesnt. In my experience it reproduces where it comes to physical contact. For example: if you have petri with bacteria in it, it will slowly grow, but it wont spread rapidly nor will new colonies start to appear. But if you had trich in petri, after sporulation (and maybe even before), new colonies would appear regardless where it all started.
I see you are confused by my intentions. Ofc i can make many petris but i want to get bag going asap. There ya go! And dont try to tell me to be patient because I learned this leason quite some time ago. I dont wanna wait extra time if i dont have to.
And btw, i would use wedges at least an inch from bacteria spot ofc.
|
Pastywhyte
Say hello to my little friend



Registered: 09/15/12
Posts: 37,810
Loc: Canada
|
|
Bacteria is microscopic. If your sure that none of it had managed to grow under your culture then do it. Me I would make a transfer and be sure. I'm not even sure why your asking this, you already seem to have made up your mind.
Edit: if you think bacteria can't move around a plate with amazing speed, you obviously have not done much agar work.
|
dusttodust


Registered: 11/26/12
Posts: 491
|
|
Could bacteria get under colonized mycelium on agar? Hmm, than that would be bad yes.
Im not sure how things exactly biologically works, thats why im asking. But im sure the bacteria stain got overwhelmed by strong monoculture very soon and it looks like to me that mycelium made biological barrier very quickly. But if bacteria can spread through air im makin new petri asap of course.
I havent made up my mind rly but i cant naively take everything as a truth i read here, no offense. Im considering 2 options: bag or transfer&test jar to see what happens. I can always go g2g with jar.
Thanks for help anyway
|
NOS4A2
This is the way


Registered: 07/22/04
Posts: 572
Loc: -tite
|
|
It's a crap shoot. Try it. You'll prolly get a percentage of jars that will be fine. But you will be wasting time and resources because you could be getting close to 100% usable jars. That is the reason for doing the agar, right? But I really don't have any more experience than your self so experiment and figure it out for yourself. Maybe go get a basic microbiology book from the library and study.
--------------------
|
Pastywhyte
Say hello to my little friend



Registered: 09/15/12
Posts: 37,810
Loc: Canada
|
|
Most bacteria are not airborne of course, but they travel on the surface of a plate quite quick. The mycelium can overtake them sure, but how far out did the really small colony's make it out before the mycelium took over, well its hard to say. That's why we transfer as small a section as we can from the leading edge to avoid picking any up and transferring it to the next plate. As we usually want a fairly large wedge for inoculation compared to a simple transfer, its in your best interests to use a plate that you know is clean.
|
|