engleski

Comparison of the growth of diatom Skeletonema grevillei in a bioreactor and an incubation- shaking cabinet

Diatoms have been recognized as an excellent source of various bioactive compounds with different applications in the pharma, food, and cosmetic industries. The big challenge in the exploitation of this microorganism is small biomass accumulation during the growth. To increase biomass production, it is important to establish optimal growing conditions that will ensure the highest yield in the shortest time period.The aim of this investigation was to compare the growth rate of diatom S. grevillei in two systems: i) bioreactor ; ii) incubation-shaking cabinet, and to determine the growth curves in the systems. Firstly, 50 mL of inoculum (same cell density) was added to the volume of 2 liters of F/2 medium. Inoculated cultures were incubated for 13 days at 17°C. The growth was monitored in regular time intervals in each system using both the Sedgwick Rafter method and the flow cytometry method. In the first growth phase, the lag phase, the results of flow cytometry in both culturing systems gave similar results to the Sedgwick Rafter method. The largest deviations between these two methods were observed in the exponential growth phase for both systems. Finally, during the last two days of cultivation, the results significantly differed between the culturing systems. In the bioreactor, there were minor deviations between the growth results determined by the Sedgwick Rafter method and flow cytometry, while in of these two methods were observed in the bioreactor, which is not the case with the incubation-shaking cabinet. A deviation of 30% was recorded on the 12th day of cultivation, while on the last day of cultivation the deviation was 40%. Both methods confirmed that the bioreactor system should be used to obtain higher yields during the same culturing period. The results of this study contribute to the improvement of the cultivating protocols for microalgae needed for better exploitations of their metabolites.

Diatom ; Cultivation ; Flow cytometry ; Sedgwick Rafter

nije evidentirano