Using isoflavones to test plant growth

[cathyg3]

Hello, I'd like to use isoflavones to test their effect on the growth of Arabidopsis thaliana plants. Common isoflavones are genistein and daidzein, which are sold as nutritional supplements. This would be the cheapest, easiest way for me to get isoflavones to test, but I'm not sure how I should prepare them or use them on the plants. I'm also worried that the other ingredients in the pills will affect the plants. The other other ingredients are: Microcrystalline cellulose, vegetable cellulose, silica, caramel, titanium dioxide, vegetable magnesium stearate, vegetable glycerin. I guess I would grind up the pills and see if they dissolve in water. Also, I'm wondering if there's a way to test the solution to tell if the isoflavones are active. Thanks!

[donnahardy2]

Hi cathyg3,

Welcome to Science Buddies! You have an excellent and unique idea for a science project. Here is a project idea from this website that you could adapt for your project that includes useful details for setting up the experiment.

http://www.sciencebuddies.org/science-f ... #procedure

Most of the research on these compounds has been done on mammalian cells.

http://en.wikipedia.org/wiki/Daidzein

http://en.wikipedia.org/wiki/Genistein

Here is an interesting reference article that suggests a biological function of isoflavones in plant growth:

http://www.bashanfoundation.org/horst/h ... trogen.pdf

The Wikipedia article has a unreferenced statement on the function of isoflacvones in plants, to help protect against pathogenic fungi and other microbes and to stimulate symbiotic bacteria for nitrogen-fixing. You should look further and try to find actual scientific references for this information.

http://en.wikipedia.org/wiki/Isoflavones

The analysis of isoflavones would be difficult, so it would probably be best if you could contract the supplier of the food supplements and ask if lot-specific analysis is available. Then you could purchase that product and request the certificate of analysis from the supplier. If this is not available, you will have to rely on the product label for concentration information.

Thanks for including the details on the inactive ingredients. It would be best to use the pure isoflavones, if these are available. However, n0ne of the ingredients in the pills contain potassium, nitrogen, or phosphorus, which would be expected to affect plant growth. However, the element magnesium is the central atom in chlorophyll molecules. So for your negative control, you will have to find out how much magnesium is in the pills and add it in the same concentration.

You can find magnesium at your local pharmacy; it is sold as Epsom salts.

http://www.lclabs.com/MSDS/D-2946MSDS.php4

http://www.chm.bris.ac.uk/motm/chloroph ... hyll_h.htm


Daidzein and genistein are not soluble in water. Here is information for daidzein, which suggests first dissolving it in DMSO and then diluting 1:10 in an aqueous buffer:

How are you going to measure plant growth in your experiment?

Donna Hardy

[cathyg3]

Thank you so much for your response! We haven't found out yet from the teacher how we're going to measure or observe the plants, but it will be over 6 weeks.

[donnahardy2]

Hi cathyg3,

You are welcome. I was just checking to make sure you were planning to do quantitative measurements. Here is information from the Science Buddies website for measuring plant growth. The suggestions for measuring young plant growth will probably be applicable to your project.

http://www.sciencebuddies.org/science-f ... owth.shtml

Six weeks is a good amount of time for a plant growth project, so it's good that you are starting early.

Donna Hardy