Jay Ha #2 growing e coli and collecting data

This week had been full of bacteria. 

Now that I am sitting in front of my laptop trying to get my weekly journal stuff done, I wish I had taken more photos. I guess I will take more photos next week. 

This is one of the few photos I took before autoclaving these bacteria and saying goodbye to my weekly production of lovely bacteria . As you can see, there are many plates, and all of these plates contain somewhere between 0 to tens of thousands of colonies of E Coli bacteria that I had grown. YaY!

My lab works started with production of more phosphate buffer solution and LB Broth. It wasnt that hard as I had to put some pills or powdery materials into the beaker using precise scientific scales and mixing them with DI water and shake them and put them in sonic machine that evenly mixes the solution. All solutions prepared had to be autoclaved to create a sterile environment. The phosphate buffer solution would be used in serial dilution method of E Coli culture to prepare E Coli of varying concentration. Some of the LB Broth, or the source of food for bacteria, are used to directly culture E Coli population in a shaking incubator set to 37.5 degrees Celcius, and other portions of LB Broth are mixed with solidifying agent so that they would be prepared to plates as seen in the picture above for the grown E Coli cultures to be tested for their growth pattern. 

Plates were prepared under bio safe fume hood. Making forty plates is tedious but does not take that long time. When the E Coli culture that used to be frozen is defrozen and incubated and all prepared, they are serially diluted to the factors of 1, 10^-2, 10^-4, ....., 10^-8. This is done by adding 0.1 mL of E Coli culture or serially diluted cultures into 9.9 mL of phosphate buffer. 

Then, these serially diluted solutions containing E Coli are spread onto the plates using glassware that spreads the culture onto the plates. Five sets of plates are prepared on every two hour intervals for 20 hours and put in the incubator to be counted in next 24 hours. After 24 hour intervals these plates are counted for the number of colonies of bacteria that had grown overnight. 

OD measurements using spectroscopy machine are taken in varying time intervals to see the correlation between OD measurements and CFU. 

I have prepared and counted the bacteria for five sets of two hours intervals everyday and had conducted this for four days total. 

First sets of data were discarded because bacteria were poorly cultured because the incubator was partially broken, so the data taken from third and fourth days are below. 

Time (h)	OD at 600nm	Count	Dilution Factor	CFU/mL
0	-0.0048	335	1	3.35E+03
2	-0.0018	301	1	3.01E+03
4	-0.0063	512	1	5.12E+03
6	-0.0223	45	100	45000
8	-0.0021	309	100	309000
10	0.0123	61	10000	6.10E+06
12	0.771	165	1000000	1650000000
13	0.8125
14	0.4506	290	1000000	2900000000
15	0.8439
16	0.9864	161	1000000	1610000000
17	1.0974
18	1.1149	301	1000000	3010000000
19	1.196
20	1.208	261	1000000	2610000000

Here are three graphs from data collected this week. 

Next week, I will be conducting research that deals with disinfection that had been catalysed through oxidation processes. Sounds fun. lol