Asthfx

My bad I meant the volume would increase (don't know what was I thinking about).

I think you're confusing density with volume, if some of the water had spilled the volume would have also diminished, so the density, which is mass / volume, would remain the same. If other material were inside the water the total volume would increase but the volumen occupied by the water would be the same and so would the density. You'd have a lower density if the water was frozen; the mass of it would remain the same but the volume would have diminished, so the density would be lower (that's the reason ice floats on liquid water). Maybe you can think about the other questions?

Could you show your thoughts? Maybe elaborate what's happening in each phase?

At higher temperatures the enzime performance should decrease as it denatures. Don't now why you're getting those results but have two ideas... maybe the heat is provoking the decompossition of it? And... could be some other catalyst in the liver breaking down the hydrogen peroxyde?

From what I know it's not always possible making an attenuated or inactive version for a vaccine especially for bacteria that has a more complex structure. The chances for side reactions on a subunit vaccine are also lower. When using a subunit vaccine they also use inmunostimulatory agents for a proper inmunogenic reaction. There's an interesting article I found. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2883798/

Here's an article on that topic https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4830253/

Uhm, my guess is you have an obligate halophile, maybe you can tell where you are taking your samples from? Also, found this article that may help. Biology of Moderately Halophilic Aerobic Bacteria