Optimization of Carotenoids Production from Camelina Sativa Meal Hydrolysate by Rhodosporidium Toruloides

Abstract

BackgroundPetrochemical synthetic dominates several markets, and carotenoids are not an exception. Since their applications in the food, feed and cosmetic sectors, carotenoids of natural origin are increasingly requested, but the production needs to be sustainable also in terms of initial feedstock. For these reasons we deployed the carotenogenic yeast Rhodosporidium toruloides to obtain such compounds from Camelina sativa meal, an underrated lignocellulosic biomass. As the process starts from hydrolyzed biomass, we separately optimized enzymatic and biomass loadings, to reduce the overall process costs. ResultsThe best conditions (9% w/v biomass, 0.56% w/wbiomass enzymes) were tested in different settings, in which fermentation was separate or co-current with the hydrolysis, showing similar carotenoids productions. The process was implemented in stirred-tank bioreactors, obtaining 3.6 ± 0.69 mg/L of carotenoids, and showing to be robust towards changes in different parameters. ConclusionsThese data pave the way to evaluate a possible industrialization of this bioprocess, considering the opportunity to optimize the use of different amounts of biomass and enzyme loading. In addition, the test in bioreactor is an additional step to further develop the proposed process.