Introduction: Enhanced Growth of Lactobacillus Bacteria With Gamma Source Radiation.

About: I am a part-time hobbyists biotechnologist with a photonics background. I also have a YouTube channel too. I work part-time too.

Hello, I am testing the theory of what happens if a gamma source like Attenuite ore is exposed to tubes with lactobacillus bacteria 3 billion of them with Indigo carmine over a period of a week. Will, they the bacteria die or grow faster than control?

The Uranium ore contains 48 percent by mass Uranium and is a pretty hot sample. Right near it- it reads 1119 CPM and 7.2 uS an Hr of gamma. When it was placed 1.5 cm away it read lower values of gamma radiation around 933 CPM and approx 6 uS an Hr in Radiation levels.

I tested with circular clamp a few cms above the tube and the rad source to read 150 CPM and 0.83 uS an Hr for low. I am most interested in the middle section of the cone Ore (0.26 ml volume exposed to medium gamma source)- 3.4 uS an Hr.

Step 1: Materials and Reagents.

Danger: Your dealing with an intense radioactive source but as long as you don't handle the ore without gloves or crush it or put it on your skin for days (Don't do stupid things like this!!) the radiation exposure is near min. 5 cm away my GC only picks up 0.30 uS an Hr. (Slightly above background levels).


Uranium ore min 48 percent.

Lactobacillus probiotic bacteria.

Powdered Milk sugar.


Hemp protein mix (White in color) mine was brown -cocoa.

Tap water.

Indigo carmine 0.1 percent.


50 ml centrifuge PE tubes with screw lids.

20 holders for 50 ml centrifuge tubes.

bricks to hold ore in styrofoam package eye level to exposure tube.


Methods for making culture one.

5 g of sugar, 3 grams of protein mix and 0.5 g of bacteria culture to 50 ml tap water and add 1 ml of dye (Indigo Carmine). Label with a magic marker (Rad exposed bacteria, Bacteria non -rad exposed and Control). The control is just tap water with 1 ml of Indigo carmine!

The second batch contains 5 g of powdered milk sugar, 0.5 g bacteria culture, 50 ml tap water, and 1 ml of dye to two tubes one is Rad exposed tube and the other is the non rad exposed tube. A control which is blue (Indigo carmine in tap water) is used as well.

Step 2: Growth of Regular Bacteria in Dye Without Lactose Milk Sugar.

For the regular bacteria growth the bacteria (Lactobacillus) was near 3 billion but every 24 hrs it would multiply by 2 by the 24 power in the culture mix. So trillions of cultures grew but it hard to tell exactly how much more bacteria in radiation from gamma exposure there was since i don't have a good method like a Mass Spec or Spectrometer.

The most important graph is the Medium exposure it constant for both trials of bacteria. Within 3 days the color change is clear for gamma exposed bacteria. In 5 days biofilm had already formed!

Step 3: Growth of Lactobacillus Bacteria With Milk Protein Sugar Mix and Dye.

This test forms a yogurt-like material that floats in solution and the dye breaks down much more evenly than before. You can set data to determine how much dye at the top of the tube got broken down. Here I had the rad source start showing results on day 3 while the non-radiation exposed bacteria took 5 days.

It clear from this that the rad source gamma speed up the reaction with the bacteria thus the dye was degraded much faster than control.

Here a table on the growth of bacteria and dye breaking down for the rad source.

Day 1 - None.

Day 2 - 1 ml.

Day 3 - 10 ml.

Day 4 - 20 ml

Day 5 - 35 ml.

Day 6 - 50 ml.

Step 4: Conclusion for Lactobacillus Bacteria Exposure to Gamma Source.

My conclusions that are for this bacteria the gamma source at 3.42 uS an Hr at a volume exposure of 0.26 ml of the total 50 ml sample enhanced growth really quickly.

It can be seen with the tubes first time around without lactose milk powder (just sucrose not lactose and sucrose) combined with Indigo Carmine. However, the milk powder mix produced more yogurt-like material in the tube as the dye broke down so a qualitative measure per day could be calculated.

I am not sure but what would happen if this was done with a sporing bacteria like a bacillus type (non-pathogenic)? Would the gamma induce endospores thus slowing down growth or is the gamma radiation too weak to do this?

Well, remember the clover project I did with alpha, gamma, beta sources? It too was too weak to have much of an effect and plants have a much more complex system (Cell structure) than Bacteria do. I don't think gamma radiation at 3.42 uS an Hr on a Bacillus bacteria would have any significant effects.

You can get on eBay Uranium oxide ore UO2 which is much more of a radioactive source for 60 dollars CAN + 40 dollars shipping legally without requiring a permit for the Rad source. The count was 9000 cpm and would produce a greater exposure volume compared to 0.26 ml for my case. This may have a positive effect but I did not want to pay over 100 dollars for a sample and time was not on my side, it would have taken a while to get here. However, it may be something I may do with other bacteria.

I was NOT expecting the gamma source to speed up the growth of the lactobacillus mixture at all but it did and I am very amazed at that!

Again THANKS for reading this Instructable by me.