I averaged OD600 measurements from two identical trials (a duplicate of every condition) - we took measurements twice for each trial, but the first set of measurements were inaccurate due to lack of mixing of culture before aliquoting into plate. The average standard deviation was 0.067. The data suggests that more nutrients (2YT > LB) and the addition of fructose results in faster growth regardless of growth temperature or expressed plasmid. This makes sense: more nutrients means more substrates for the cell to use in protein production. The fructose effect could either be because it's simply an additional sugar (energy) source, or potentially also because fructose is one step after glucose in the glycolysis pathway, such that one ATP molecule (energy unit) is saved for each fructose used by the cell instead of glucose. It appears that growing at 30C results in slightly greater cell density, likely because of how temperature effects the expression of the plasmid and the metabolic cost to the cell as a result of that. Cultures expressing pAC-LYC appear to have greater cell density than those expressing pAC-LYCipi, which makes sense since the former has one less protein to expend resources on. It seems possible that after fructose is added, pAC-BETAipi expressing cultures have greater cell density that pAC-LYCipi expressing cultures.
After we performed acetone extraction of the pigments from the cells (acetone precipitates the cellular proteins but dissolves lycopene and beta-carotene), we used the plate reader to calculate absorption spectrums for each sample. The beta-carotene absorption peak at its maximum absorption of 456 nm was much higher than the lycopene absorption peak at its maximum absorption of 474 nm. (In the picture below, the columns are in reverse order of the culture chart in the protocol.) The hypothesis is that beta-carotene absorbs light better than lycopene.
We also measured the optical density of the acetone-extracted pigment solutions, at both 456 nm and 474 nm. Here I'm using data from a classmate. I used all the measurements (duplicate measurements of duplicate trials for a total of 4 replicates) except for two clear outliers. The average standard deviation for both wavelengths was about 0.043. Note that the numbers in each graph do not directly correlate to quantity of beta-carotene or lycopene respectively; there are other pigments that are produced, for example zeaxanthin, whose absorption spectrum overlaps with that of beta-carotene and lycopene, including each other's.
As was the case with cell density, the lower temperature culture incubation resulted in higher production of pigments. Interestingly, for the cells that were both 1) transformed with plasmids containing the production-promoting idi gene (LYCipi and BETAipi) and 2) grown at the higher temperature, the addition of fructose decreases production of pigment.
Beta-carotene is widely acclaimed for its health benefits for its antioxidant properties and for being a precursor to Vitamin A. But how good it is for you could depend on the person; according to Sigma-Aldrich, beta-carotene “reduces the incidence of many cancers, but enhances lung cancer incidence in smokers.”