Curcumin and fisetin internalization into Saccharomyces cerevisiae cells via osmoporation: impact of multiple osmotic treatments on the process efficiency.

UNLABELLED

Cell osmoporation is a simple and straightforward procedure of creating food-grade biocapsules. This study proposes a new protocol of sequential cell osmoporation stages and evaluates its impact on the efficiency of curcumin and fisetin internalization into Saccharomyces cerevisiae cells. To the best of our knowledge, this is the first report in the literature regarding the subject. To assess how multiple osmoporation stages influence the encapsulation efficiency (% EE), encapsulated amount of curcumin (IC) and fisetin (IF) into S. cerevisiae cells and cell viability, the residual supernatant was used for the subsequent encapsulation stages and viability was assessed by the CFU method. Quantification was carried through direct extraction, using an ultrasonic bath and UV-Vis spectrophotometry. Experimental data demonstrated that the addition of a second osmoporation stage increases both the EE (% EE) and the amount of encapsulated curcumin and fisetin (IC and IF). As a result, the EE was considerably improved and the obtained microcapsules contained a higher amount of the targeted bioactive compounds in its internal structure. However, adding a third osmoporation stage proved to less beneficial to the process efficiency due to its lower yield and the significant negative impact to cell viability.

SIGNIFICANCE AND IMPACT OF THE STUDY

For the first time in the literature, a protocol of serial osmoporation stages to enhance the encapsulation efficiency of hydrophobic low molecular weight molecules (curcumin and fisetin) into Saccharomyces cerevisiae cells was determined. By increasing overall efficiency, this protocol empowers the encapsulation process and creates a rational way to reduce waste for future industrial osmoporation applications.