Sunday, November 9, 2008

Week 20 SIP

Hi all this is the last week of SIp, well actually its already over. Hope you all enjoyed you SIP and well its time for reports to be handed up and for school to resume.For this round I will be touching on undefined organic elements solidfying agents

Undefined organic elements include protein hydrolysates, coconut water, yeast extracts, activated charcoal, malt extracts, ground banana, orange juice and tomato juice. The addition of activated charcoal to culture media may have a beneficial effect. It can stimulate cell growth by its ability to bind to toxic phenolic compounds produced during culture. Activated charcoal is usually added to the media, acid wash prior to addition at concentration of 0.5% to 3.0%.

Agar is the most commonly used geling agent for preparing semisolid and solid plant tissue culture media. Advantages of agar: it forms a gel when mixed with water that melts at approximately 60-100 degrees celcius and solidifies at approximately 45 degrees celcius. It also does not react with media constituents and will not be digested by plant enzymes. The firmness of the agar gel is controlled by the concentration nad brand of agar used. Typical concentration used is 0.5% to 1%; the concentration give a firm gel at the pH lvels typical of plant culture media.

Another geling agent would be gelrite, it is a product of bacteria fermentation and should be used at 1.25-2.5 g/L, resulting in a clear gel which aids in detecting contamination.



MadTechs said...

Hi Johan

Since you are posting on gels for your last blog posting, I would like to ask a question regarding it. Did you know that gels could also be used as an embedding medium to provide some support for the tissue to be cut.

Let's say: I wish to embed a freshly obtained organ from a rodent in a gel. (Critical factor: I wish to keep the maximal viability of the organ possible) So that I could observe the sectioned tissue on a microscope.

What factors of the usage of the gel should I look out for? (From the process of making the gel to embedding the organ with the gel to the process of tissue sectioning)

There's no fixed answer for this, so don't sweat it too much =)

Many Thanks
Quan Jun
TG 02

tg01 group 2 said...


You mentioned about undefined organic elements solidfying agents. however u didnt discuss about the benefits,advantages or limitations of it. So is it possible to ask if there are any benefits,advantages or limitations?