Saturday, November 20, 2010

Things that explode and my new definition for "frisky."

This is not the explosion that occurred, but I would have preferred this:

I have some big experiments coming up, and I need a TON of culture to complete them.  By a ton, I mean 3-4 liters.  This includes my anaerobic cultures.

I spent the week cultivating some awesome dense and fast growing starter cultures of about ~80ml.  I call these "frisky" because if I take a syringe full of nitrogen, and push the needle into the bottle, the culture spurts into the syringe before I can plunge all the nitrogen gas in.  I tend to put personalities to my cultures, and for whatever reason, the first time I saw this happen I thought, "well that's frisky."

The culture is producing hydrogen gas, and it grows so fast that there's TONS of pressure in these small bottles.  I use a small amount to re-inoculate smaller starter cultures, and hope to relieve some of the pressure.

Then, under nitrogen gas, I open the bottles (they sound like champagne bottles popping), dump the culture into my large 1 liter jars, and seal it up.  These are then incubated at 85 degrees C.  Dumping ~80ml of culture into ~1 liter dilutes the culture, and I'm thinking that by ~24 hours, these bottles will be ready for harvest.  Easy peasy.

Today I'm well rested, well fed, and walking up the stairwell.  I should explain that our lab is in a bit of shambles, and we're in the process of moving soon, so the high temp incubators are in the hallway.  The moment I turn down the hallway....I smell it.

Instantly I know that something absolutely wrong has happened with the anaerobes.  
Basically, they ferment the sugars at a high isn't a good ferment like beer, it's an evil waft you get when you have food gone wrong in your fridge.  And it's still 25 feet from where I'm standing.  THAT is how horrid it is.

And in the back of my head, I knew something like this could happen.  I just thought that it would have taken more time.  
The leak of culture is so bad that it's triggered the sensors to go into error mode, and the heat has shut off.  I open the incubator, and thankfully only one of the four liter bottles have exploded.  I still have 3L left (which is sufficient for my experiments).  

But this wasn't a leak.  This was an all out explosion.  The rubber stopper is still lodged in the neck of the bottle, with the cap in place.  There are bits of shattered glass EVERYWHERE.  I think that must be a LOT of pressure.  

And I should've known better.  There should have been more head space in the bottles, but I'd been having problems with oxygen getting in the media, so I decided the less, the better.  
Fortunately, because the incubator shut off, the temperature dropped, the remaining culture quit growing, so they didn't go 'splody as well.  

But boy, are those cultures dense.  Here's a comparison of an un-inoculated culture (with some oxygen in it, hence the orange/pink tinge to it) next to one of the surviving bottles:

So yah....I'll be cleaning and cleaning....and cleaning again.  I've notified my PI, and I'm worried that I might have damaged the high temp incubator.  The sad thing is...I showed up ~17 hours after I inoculated the culture.  Had I been a little sooner, it might have been avoided.  And I'm curious as hell if it made a huge bang or anything.  Tiny shards of glass were stuck ALL over the incubator.

I'm also lucky.  If I had arrived earlier, I could have removed the bottles, and that one particular could have continued to grow and produce gas and pressure while sitting out on my bench.  In which case, it could have exploded near me, spraying glass and the bog of eternal stench onto me.

I also hope the smell dissipates a ton before Monday.  I'm about to become quite unpopular in my department.

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