Optimization of the <i>in-situ</i> growth conditions based on a novel photo-microcalorimeter for the sustainable cultivation of photosynthetic microorganisms

Despite the great potential of photosynthetic microbes in the production of renewable fuels, value-adding chemicals, and water treatment, etc., commercial utilization of them is significantly hindered by the lack of techniques to accurately monitor the thermodynamic and kinetic characteristics of the In-situ growth of microbes under controlled light illumination for optimal cultivation. Herein, we demonstrated that a newly developed highly sensitive photo-microcalorimetric system successfully captured the impacts of the light wavelength and strength on the thermodynamic and kinetic parameters of the In-situ growth of Rhodopseudomonas palustris, a representative photosynthetic microorganism. To our best knowledge, this is the first time that highly precise microcalorimetry is employed to monitor exam the in-situ growth of photosynthetic microorganisms under controllable photo illumination. We envision this technique can help for the optimization of the growth conditions of photosynthetic microorganisms for scale-up applications.