Koenraad Muylaert

Cultivation of Chlorella vulgaris and Arthrospira platensis with Recovered Phosphorus from Wastewater by Means of Zeolite Sorption

In this study, zeolite was employed for the separation and recovery of P from synthetic wastewater and its use as phosphorus (P) source for the cultivation of the green microalga Chlorella vulgaris and the cyanobacterium Arthrospira (Spirulina) platensis. At P-loaded zeolite concentration of 0.15–1 g/L, in which P was limited, the two species displayed quite different behavior regarding their growth and biomass composition. C. vulgaris preferred to increase the intracellular P and did not synthesize biomass, while A. platensis synthesized biomass keeping the intracellular P as low as possible. In addition under P limitation, C. vulgaris did display some little alteration of the biomass composition, while A. platensis did it significantly, accumulating carbohydrates around 70% from about 15%–20% (control). Both species could desorb P from zeolite biologically. A. platensis could recover over 65% and C. vulgaris 25% of the P bounded onto zeolite. When P-loaded zeolite concentration increased to 5 g/L, P was adequate to support growth for both species. Especially in the case of C. vulgaris, growth was stimulated from the presence of P-loaded zeolite and produced more biomass compared to the control.

Microalgal Feed Supplementation to Enrich Eggs with Omega-3 Fatty Acids

Abstract The health benefits related to omega-3 long chain polyunsaturated fatty acids ( n −3 LC-PUFA) are generally known. However, average human consumption of these fatty acids is low and does not meet the daily-recommended intake of 250xa0mg/day in most countries worldwide. Influencing the n −3 LC-PUFA composition of eggs could serve as a possible solution. Several n −3 PUFA sources, such as flaxseed, fish oil, or heterotrophic microalgae, can be added to the diet of laying hens to enrich eggs. Another source, autotrophic microalgae, when supplemented into the feed of laying hens, also results in enrichment of eggs with n −3 LC-PUFA along with carotenoids leading to additional health benefits for humans consuming these eggs. This chapter discusses the use of autotrophic microalgae as a sustainable source of n −3 LC-PUFA for the enrichment of eggs.