How to make an agar plate

[salunete]

thank you :)

[MicrobiologyLearn]

This is a great question. Bacteria are able to break down red blood cells and this is called haemolysis. Around a colony you can sometimes see a clear halo where the red blood cells have proken down and this is called beta-haemolysis because the break down is complete. I love sheep blood agar as you can sometimes see double rings of haemolysis, an inner beta and an outer ring of partial. I've use human blood but never chicken to make blood agar plates.

[st3v33100]

Thanks for posting this video. But i have a question, can we use another blood, like chicken blood for example? Thx

[orglancs]

This is very interesting and I could just about follow it from the actions, even though, with a UK ear, I could hardly understand a word of what she said. The background noise made it very hard to hear what she was saying. Intelligent questions, too. I shall watch a few times and probably get used to her accent. Thanks for posting.

[MicrobeGarden]

This is an interesting question. Most laboratories have there coat racks just as you come into the lab so the first thing you do is put on your coat. When leaving the lab the last thing you do is take off your coat. To keep the ties clean you must wash your hands before taking off the coat.

[joshua99999999]

Like after a certain amount of time you could see certain small plaques for example when you see the virus has taken up the nutrients and has left waste or either died?

So you can then continuously feed the samples of the influenza strain through the blood agar and allow the amount you have to grow and expand even more?

Just a small thing I was thinking of and was just wondering if it was possible to do so,

Please reply,

Thanks a lot =)

(Couldn't PM due to friend lock, sorry)

[MicrobeGarden]

Viruses don't take up nutrients, they do not metabolise. New virus particles are made by the host cell, just like how the cell makes proteins and new nucleic acids by reading genetics information, in this case they read the viral nucleic acid instead of the host cell nucleic acid. Influenza virus cannot grow in red blood cells as they are metabolically inactive. You need to get chicken aggs that are fertle and have clees grwong inside the. Influenza virus can be grown in such eggs, not agar.

[joshua99999999]

When you said about how you might not be able to culture viruses on an agar plate with bacteriophages as exceptions, If you take a strand of influenza, Can you not culture this on a blood agar plate? Because since there is still red blood cells for the virus to infect and replicate out of you should be able to gain a viable amount of influenza right?

[joshua99999999]

Hey, I have a question, Since this is blood agar - And the experiment with regular agar mainly is for growing bacteria, Can you not allow a virus to grow/spread throughout the blood agar as there would still be red blood cells in it, or is that not the case?

And thanks for uploading =)

[MicrobeGarden]

Good question. Red blood cells are very interesting cells. Since they have lost their nucleus they are probably not metabolically active enough for viruses. There are viruses that will grow on agar plates as long as there are bacteria on the surface. These viruses are called bacteriophages.

[joshua99999999]

@MicrobeGarden Oh right, I was looking at that, Because isn't there viruses that would infect the bacteria to speed up the creation of viruses? - Bacteriophages as you say, Awesome, Because I was thinking of doing this experiment of trying to culture bacteria on an agar plate but need to gain some more equipment to do it, and was just wondering if it was possible to culture virus cells instead of bacteria =)

Thanks again :)

[Ch0l0P0ch0l0]

Thanks for posting this! It is really very helpful. It seems that you are faking yor accent though but I love it too hehehe! Have a nice day and good luck to your career!

[MicrobeGarden]

Thank you for your feedback. I like your question as I am reminded of the issues that are forgotten when non-microbiologis make agar. You need to consider how 'defined' your media is. If you were doing an experiment and wanted to control what your insects were eating then you would want to make sure it was not partially degraded by contaminants. Some contaminants grow so slowly you may not realise how degraded your media is. Also don't keep the agar hot for long as this will also degrade it. :-)

[katie89100]

Thanks for uploading this video, it's great. You may not know this if you're a microbiol but do you think the procedure would need to be so strict about preventing contamination if you were making media for insects? Thanks.

[HarryPotterTrio91]

Do you have videos on how to stain a slide?

[MicrobeGarden]

Yes, but I want to add a little footage on tips to preparing a smear so I'll do this in the next month and upload by the end of January!

[isaimartinez70]

im doing a science project and want to know where to get it please e-mail to davidsworld93@yahoo.com.please need by december 2,2010.and thank you.

[MicrobeGarden]

Hi, not sure I understand what it is you want. Can you be more specific?

[gdykes]

I had know idea agar plates where made this way, thanks heaps!

[Apieisdebest]

For 25 ml of agar, how much agar base would you need?

[Rocketboy1950]

It depends on the formulation of the agar base. On the side of the container you are told how many grams per 1 litre. So just divide that weight by 40 for 25 mls. Note: be careful autoclaving small quantities of agar, the percentage loss of water through evaporation will lead to overly concentrated solutes, cheers

[Kratosmustdie]

Why is the mixture boiled before putting in autoclave, and what woudl have happened if you did not boil it?

[MicrobeGarden]

Hi, this is a very good question. It depends how certain you want to be about sterility. Boiling ensures all lumps are disolved. If lumps remains during autoclaving, the centre may not sterilize due to its viscous nature. Manufacturers also recomend you add half the water, then powder then rest of water to wash down sides of the flask so that no small lumps above solution and possibly don't get sterilized. Most clinical labs that make their own agar plates don't bother with the pre-boiling step.

[Kratosmustdie]

Ahh, so to reduce turbidity in the agar so that you can view colony growth and for sterility, would it also be boiled to keep the mixture in liquid form until you autoclave, or is room temperature not cool enough for the solution to harden, thanks for response btw, really helpful