I remember when I was a bleeding heart liberal I had this project in college where I was thinking about how to get biofuels to be economically competitive with fossil fuels. A flawed premise, but clearly they were trying to do good in the world. One of the papers I was using was using some kind of waste sugar to fuel them. I don't think I can find the exact one but

Utilization of biodiesel-derived glycerol or xylose for increased growth and lipid production by indigenous microalgae

Is close. Much of the study was about perfecting the algae that they were using, not indigenous microalgae.

Microbes are little expert chemists and the composition of triglycerides, glucose, and amino acids are well understood. We can use, if memory serves, E. coli to synthesize insulin. We can use microbes to eat plastic.

Sounds sound to me.