what is culturing

micronub · Post by **micronub** » Thu Aug 02, 2012 10:59 am

I have a question about the word culture as far as mircro-biology. When you create a culture, does this mean you have a sample and you are trying to grow what is in the sample that you have or does it mean you create a culture in hopes to obtain something you don't already have? I've been reading somethings and I am now confused.....

pwnell · Post by **pwnell** » Thu Aug 02, 2012 11:53 am

Take my opinion with a tonne of salt, but my understanding is that culturing implies growing more of something you already have.

micronub · Post by **micronub** » Thu Aug 02, 2012 12:12 pm

Thanks for your bid, any other bid's out there?

Another thing I was thinking is that maybe culturing means to have a sample of maybe dirt or lent and putting it in a culture medium in order to cultivate whatever organisms that may be in the sample..... I'm confused really about this. Do we have in rocket scientist out there that can better explain "culturing"?

Mitch640 · Post by **Mitch640** » Thu Aug 02, 2012 2:28 pm

I think it can mean many things. I know that many cultures are grown of the same bacteria, or whatever, to see what they may grow best in, or what might prevent them from growing.

It can be a noun and a verb.

Tom Jones · Post by **Tom Jones** » Fri Aug 03, 2012 10:28 am

Micronub,

At its most basic level, culturing is the creation of an environment (medium, nutrients, selective agents, atmosphere, temp, etc.) where organisms already present in the inoculum can grow and multiply. The inoculum is what you use to seed the culture and contains a small number of whatever organism(s) you are hoping are there, and trying to grow.

You cannot create something that is not already there, and alive.

Cultures can be used to increase the number of a single type of organism. They can also be used to isolate a single type of organism from many others. If you use some kind of selective agent such as temperature, atmosphere (aerobic or anaerobic, more CO2, etc.), antibiotics, salts, blood, specific nutrient types, and many, many more, you can selectively enhance the growth of some at the expense of growth of others.

Culturing pond water, weeds, soil, or whatever to look at the little animals at play is easy and great fun. If that's what you want to do there are lots of basic books and articles online to help.

Be advised, however, that evil lurks out there. There are lots of dangerous organisms present in the environment in harmlessly low numbers. Culturing blindly, without understanding what you are doing can increase those numbers to the point they can be very nasty. Care is therefore recommended.

Tom

micronub · Post by **micronub** » Sun Aug 05, 2012 6:44 pm

Thanks Tom for your input. Mostly I like to watch the pond water life and other standing water. The more I hear about this naegleri fowleri the more worried I become about playing with this standing water. I've read where 3 boys have died already this season due to that amoeba. I don't really understand "free living". I don't understand how something like that can just show up. I have some videos that I made of some type of an amoeba that I have living in a large barrel outside my house. Not sure what kind they are but they are extremely small.

http://www.photomacrography.net/forum/v ... hp?t=17667

Bruce Taylor · Post by **Bruce Taylor** » Mon Aug 06, 2012 9:44 am

micronub wrote:TI don't really understand "free living". I don't understand how something like that can just show up.

The term "free-living" just means that they are not parasites or symbionts, living on or inside another creature.

As for how they can just "show up," that's an interesting subject. Most freshwater microorganisms -- both single-celled protists, like ciliates and amoebae, and multicellular micro-animals, like rotifers and tardigrades -- can survive for long periods of time without water. The usual strategy for surviving a dry spell is for the organism to form a resting cyst (kind of like a little survival pod, containing a dormant, compacted form of the creature). In dormancy, the little guys can blow around in the air, like windborne spores or seeds.

You might be breathing some right now.

Also, microbes can hitch a ride from one pond to the next on a bird's muddy feet, or a muskrat's fur.

Naegleria fowleri is not normally parasitic...invading brains is not part of its natural life cycle! In other words, it is usually a free-living species. Infections seem to result from swimming with the head underwater, and from rinsing sinuses with unclean water (with a neti pot, for instance). If you are not introducing the water directly to your nose, I do not think you are in danger.