Sunday, May 28, 2017
Phew, a lot has happened this week, and all of it has been interesting! First, when I came back from the weekend and looked at my mini plates to see if the bacteria had grown blue, they had not! Given that the methylene blue (MB) was supposed to kill the bacteria and it appeared that the bacteria were actually metabolizing it, I decided it would be good to test this phenomenon again. I made up two plates with half of the agar blue and half of it normal, and one plate (accidentally, BECCA!) that was more of a marbled look. I then put blue bacteria from my original MB resistant plate on one of the half-and-half plates, blue bacteria from my original MB stock plate on the other half-and-half plate, and stock bacteria from the tube on the marbled plate. When I checked after 24 hours, all of the bacteria had grown on any agar that was without MB. When it came to bacteria growing on the MB, however, results varied. The resistant E. coli had grown a bit on the MB agar, but none of the stock bacteria had grown on the MB agar, regardless of whether it was from the tube or from the original MB stock plate. I am not sure as to why this happened. It is the original desired result, but it’s weird that it didn’t happen originally, and only worked on the stock bacteria this time. I will keep researching and see if I can think of anything that differed in this trial from the last one. At 72 hours, the results were the same on the two half-and-half plates, but the growth on the marbled plate had changed. Not only did it now have mold, there were also now big and large colonies all over the plate. Each colony was a different shade of blue, depending on the amount of MB available for it to pull up in the agar. The colonies in the dark blue part were very blue, whereas the ones in the lighter blue area were lighter blue. Even the colonies that grew in a basically normal agar grew with a blue tint, because they drew MB from the agar close by, I’m assuming. This confirmed that the bacteria seem to be somehow metabolizing the MB. When researching why/how they might be doing this, I found an article that said they may be reducing MB into a colorless form. I’m a little confused as to why/how they are doing this since MB was supposed to kill them...but I will keep researching. In the meantime, I also made a liquid environment for my bacteria to see if we can see anything further with that. I added MB to one of the flasks, and it would be amazing if I showed up Monday to find the liquid clear, or at least a lighter shade of blue. Lastly, today I tried to do an oil immersion in order to better see the E. coli, but wasn’t able to see anything. I repeated the procedure with stock bacteria from the tube and was successful, so I will try it again on Monday with the blue bacteria, this time somehow suspending it in liquid, because that worked well with the stock E. coli.
Sunday, May 21, 2017
This week I ran my experiment, and, as with most experiments, there were some definite hiccups. I plated my bacteria on Tuesday and started my experiment, using a blue binder divider over a small, white light to create the desired blue light effect. I was worried that the light might die overnight, but it turned out this should not have been my primary concern. When I came into school the next morning, the light was completely fine, but the stock bacteria was not. There was absolutely nothing growing on any of the stock plates, even on the control plate, so Mrs. Cole helped me make up a new batch of stock bacteria, and I re-plated. When I checked the next morning, the stock bacteria was growing no problem, perhaps too well. The bacteria growing under the blue light showed absolutely no signs of growth inhibition, and I was hoping to at least see a little less bacteria on those plates than on the control plates, but both were basically full-on lawns. With the methylene blue, the story was a little different. There was definitely not the large-scale growth inhibition I was hoping to see, but both the stock and antibiotic resistant plates with the compound were made up of very defined dots of colonies, rather than the complete coating that happened on the blue light plates. Overall, in response to my question, I would say the methylene blue worked better, although, with the available equipment, neither method is an effective way of combating antibiotic resistance bacteria.
Additionally, all of the colonies except one large one were blue, and so had obviously taken-up the dye. Mrs. Cole and I thought it would be interesting to see if the bacteria continues to grow blue if it is plated on a normal plate of agar, so I took some of the methylene blue bacteria and plated it on some mini plates to leave in the incubator over the weekend. I’m looking forward to seeing how that goes!
Saturday, May 13, 2017
So, I, per usual, have run through a number of ideas in order to arrive at my final one. I started out looking at comparing the effectiveness of natural remedies to the effectiveness of modern medicine. I found a study looking specifically at the effectiveness of green tea and a modern heart medicine at lowering heart rate, and was thinking perhaps I could use something like ginger as well, or maybe compare different teas, but then I stumbled on a new and more interesting idea. In researching other natural remedies, I found that sage and rosemary both have active ingredients that serve as neuroprotectors and help enhance memory. I was thinking I could use the mice, expose them to the two different plants, and see if that exposure decreased the time it took for them to get through a maze. But then I decided that I didn’t want to deal with the increased numbers of variables that using animals brings. At home, having run through several different ideas, I was feeling a little desperate, and asked my dad at breakfast if he could think of anything. He mentioned phototherapy having a positive effect on metabolism, so I came into school that morning and looked up phototherapy. I found a study that detailed how blue light kills antibiotic-resistant bacteria, then stumbled on another than detailed how the compound methylene blue does the same thing. What it seems no one has done, however, is compare the effectiveness of the two, so that’s what I will be looking at.
Now that I have my question (which will be more effective), I have begun looking at my procedure and laying it out. I plan using plates with antibiotic resistant E. coli and stock bacteria. I will have a control with no substance present (with one plate antibiotic-resistant, one plate stock bacteria), two plates with antibiotics, two plates with methylene blue, and one exposed to blue light. I'm doing pretty well drafting up my procedure, and am hoping to start this week. I guess the only problem with that is that I don't know how long it's going to take...Away, I'm really looking forward to this!