Kinetical modelling and CFD simulation for fucoxanthin production

Fucoxanthin is a brown pigment that found in Chromophyta, brown macroalgae and diatoms. This molecule has a great interest because it has potential bioactivity levels such as antioxidant, anti-inflammattory, anti-cancer, anti-obesity and anti-diabetic activities. Phaeodactylum tricornutum is a diatom that carries high amonut of fucoxanthin as its major carotenoid but the studies about fucoxanthin production from this microalga are limited. In this thesis, kinetical modelling of fucoxanthin production and simulation of fluid dynamics in photobioreactors were aimed. Firstly, chemical and physical production parameters were studied in 1 L bottles and as a result, production was optimized unnder the light intensity of 45 µE.m-2.s-1 at 18 oC, in F/2 nutrient medium and wtih the aeration rate of 3 L/. Subsequently, in three different photobioreactors as stirred tank, panel, airlift photobioreactors with the volume of 2 L, three different scale up strategies as constant "volumetric power consumption rate", "oxygen mass transfer coefficient", "mixing time" were studied. The best fucoxanthin yield was obtained as 2,22 mg/g cell at panel photobioreactor with "constant volumetric power consumption rate" strategy. In the aspect of the results obtained, production was carried out with a 7 L panel photobioreactor using constant P/V scale up starategy and maximum fucoxanthin amount was found 4,11 mg/g cell. A 2 L photobioreactor provided by online control was used for kinetic modeling of biomass and product. In addition, the flow profile for the 2 L photobioreactor was simulated with ANSYS V17.1 and photobioreactor design parameters were evaluated.