WHAT are new rules on culturing micro-organisms

[sunray18]

Can anyone please tell me what we are allowed to do and not allowed to do about culturing micro-organisms.
Can students still go out with cotton buds and take swabs of stair railings and desks etc or not?
My teachers say we can still do that - I don't think so...

[RosalieM]

Our kids still do. I haven't heard anything otherwise. Just not allowed to unseal the plates afterwards. Although if the plates don't get sealed to start with it's a little hard to enforce that one!! Grrr.... to the teacher responsible... (those plates are still in the classroom by the way!)

[Labbie]

I believe the CSIS says we can NOT, only known cultures can be growen. Their is a pepper corn agar plate the students can do. But for the life of me I just can not find the recipe. Perhaps a search in Chemtalk think I put it up before.

[Lis]

I think have read something here not so long ago about it, and I someone said it was only sub-culturing that wasnt allowed, please correct me if I am wrong

[dime]

WEll we still do 'em. Got 72 incubating at the moment, including 12 made with tomato paste and powdered milk to grow the yoghurt on. As has been said, make sure they are sealed and disposed of properly then there is no problem. We have never been allowed to open them for sub culturing. You would have to be mad to want to anyway. Although there is probably nothing worse on the plates that in the staffroom fridge

[nickyw]

We still do it here, just not allowed to open after innoculation.
Extract from "Microbiology - Safety considerations by Sheryl Hoffman"
Samples should never be taken from areas likely to harbour pathogens eg. toilets, bird or animal cages, dead animals and faecal material. Soil cultures may also isolate Tetanus bacteria and should not be attempte

[Kathryn]

Hey could you please give me the recipie with tomotoe sauce and milk powder?
Thanks

kathryn

[Ian]

I believe the CSIS says we can NOT, only known cultures can be growen. Their is a pepper corn agar plate the students can do. But for the life of me I just can not find the recipe. Perhaps a search in Chemtalk think I put it up before.

I got this one a few years ago (2006) at a beginner labbie course run by Kathy Morris (Hurlston Ag), Robyn Mariner (Holsworthy High) and Dearne Stephens (Liverpool Girls). It was a great course, and this recipe has served me well for several years now.

PEPPERCORN INFUSION

* Soak approximately 20g of peppercorns in 200ml of water in a conical flask. Stopper with cotton wool.
* Stand at room temperature for several days or place in incubator overnight

The bacteria is Bacillus subtilis (gram-positive rod) and can be destroyed by soaking open plates for several days in "HOME BRAND" disinfectant, then discard to garbage.

[Labbie]

Yes that is just the one I was thinking of, THank you Ian. Kathy now at Miller tech High, Robyn has retired, Thanks so much. Deanne is at John Edmondson High.

[bindibadgi]

Thanks for the peppercorn idea Ian

How long does the bacillus usually take to grow a nice fuzzy lawn? I'm guessing a couple of days?

I usually inoculate our plates with staph albus, & we used to get a lawn & distinct clear zones, but for some reason the staph just hasn't been reliable for the last couple of years, so the peppercorn version looks great to me if I can grow a lawn.

Do you have a copy of the prac you do that you're happy to share?

[Ian]

Oooo. Now you are stretching my expertise (Hey. I'm a Physicist!!) I just make up the broth and the plates and turn on the incubator and then clean up a few days later when it is all done and hosed.

The original recipe came with a suggestion of simulating anti-biotic disks by soaking small disks of filter paper in Home Brand disinfectant and placing them on the innoculated plate.

For an interesting story about the discovery and use of Bacillus Subtilis look up the following web site!. http://www.rense.com/general4/bac.htm

Cheers
Ian

[bindibadgi]

HAPPY HAPPY JOY JOY

Just checked my peppercorn plates, & overnight a lovely thick culture of Bacillus has grown!

Bacillus plates.jpg

A HUGE THANK YOU to Ian for the suggestion......I'm gratefully converted to the peppercorn plates now, bugger spending money on Staph & E.coli broths when it's so easy to whip up such a luscious fast growing culture
It's so consistent across the plates too......the last couple of years the Staph grew on some plates & not others for some reason, but yesterday I poured 4 plates, & today all 4 plates have lawns with the same thickness & an even spread!
This yet another example of how Chemtalk has solved a problem, & how much this labbie forum absolutely rocks!

[dime]

Hi Kathryn
I have only just seen your post.
For 10 plates I use the usual rounded teaspoon of nutrient agar, then add 2 heaped teaspoons Powdered Milk, 1 heaped teaspoon Tomato Paste and approx 200ml warm or hot water to dissolve in a beaker and cover with foil and the usual pressure cooker for 12 minutes. It is apparently used for cultivating Lactobacillus species. This is my modification of the tomato juice agar recipe, and the teacher has been happy with the results, but that is not to say a microbiologist would be.
Cheers

[Kathryn]

Thanks for that recipie. I'm keen to try it out.

kathryn

[RosalieM]

Are they fresh peppercorns or just the ones you buy a the supermarket?

[Ian]

Just "Masterfoods" or whatever you can get in the Spice section of Woolies or Coles works fine. They last a while, so just keep a jar in "Stock", or, alternatively keep them in a Grinder in the Lunch area (for the tomato sandwiches) and just take out what you want when you need to!!

I am glad that some of you have found the Peppercorn recipe helpful because, as good as it is, I can not convince MY teachers to use it!!! They all insist in going contrary to CSIS and growing "Wild Cultures" off the stair railings and door knobs, etc.

Cheers

Ian

[Labbie]

Same here Ian, it really is a up hill climb.

[Narelle01]

I just showed a bio teacher the peppercorn and the pic, she is keen to try it out.

[Lis]

Maybe if you put the culture into a specimen jar, labelled it Bacillus subtillis gram +ve bacteria etc, make it look all official and tell them it was a sample sent to you to try out just a thought my bio teacher is happy to try it out, so I thank you Ian

[mtg]

If the plates are taped around the edges after exposure and never untaped and then autoclaved, is the dreadful stuff grown from door handles etc ok? Will be trying peppercorns for biol but Yr8 microbes will probably still be looking at what grows from what and where!!!!