Biological Activity of Hydrophilic Extract of Chlorella vulgaris Grown on Post-Fermentation Leachate from a Biogas Plant Supplied with Stillage and Maize Silage
Algae are employed commonly in cosmetics, food and pharmaceuticals, as well as in feed
production and biorefinery processes. In this study, post-fermentation leachate from a biogas plant
which exploits stillage and maize silage was utilized as a culture medium forChlorella vulgaris. The content
of polyphenols in hydrophilic extracts of the Chlorella vulgaris biomass was determined, and the extracts
were evaluated for their antioxidant activity (DPPH assay), antibacterial activity (against Escherichia coli,
Lactobacillus plantarum, Staphylococcus aureus, Staphylococcus epidermidis) and antifungal activity (against
Aspergillus niger, Candida albicans, Saccharomyces cerevisiae). The use of the post-fermentation leachate was
not found to affect the biological activity of the microalgae. The aqueous extract of Chlorella vulgaris
biomass was also observed to exhibit activity against nematodes. The results of this study suggest that
Chlorella vulgaris biomass cultured on post-fermentation leachate from a biogas plant can be successfully
employed as a source of natural antioxidants, food supplements, feed, natural antibacterial and antifungal
compounds, as well as in natural methods of plant protection