Potential of leek (Allium ampeloprasum) waste for microalgae Chlorella vulgaris cultivation: A preliminary evaluation

Leek is an economical and healthy plant species. It contains rich dietary fibers, amino acids, bioactive compounds that increase its antioxidant capacity and more than 20 different fatty acids. It is rich in potassium, iron and selenium and can be used as a valuable source for microalgae cultivation. For impotance of leek, this study investigated the biomass production of Chlorella vulgaris microalgae species with leek leaf waste. To obtain the leek extract to be used for the experiment, leek leaves were dried in an oven at 40 °C and crushed in a mortar and pestle and filtered. Leek leaves were first dissolved with 10 ml DMSO (Dimethylsulfoxide) to 0.1 g/L and diluted with distilled water to a final volume of 100 ml. Chlorella vulgaris was exposed to leek extract concentrations of 0.01, 0.025, 0.05, 0.1 and 1.0 g/L for 72 hours and BG-11 enrichment medium was used in the control group. According to the data obtained, when leek leaves were used in the cultivation of C. vulgaris microalgae, a very high increase of 160% was observed at a concentration of 0.05 g/L compared to BG-11 enrichment medium. However, in the group where leek leaves were used completely, 64% increase was observed compared to the control group. This study proved that C. vulgaris have significant potential for food industries and the biocompost of vegetables is a suitable medium for microalgae cultivation. This study has proven that the use of vegetable wastes is suitable for obtaining a culture with high biomass of C. vulgaris microalgae, which has been used intensively in different areas of the food industry, and that leek wastes in particular provide high biomass growth. Therefore, the lower concentration of leek served as the best medium to increase the growth and biomass of C. vulgaris. This study proves that costs can be reduced and sustainable effective culture techniques can be used in microalgae culture by using vegetable wastes such as leek waste, which provides high biomass growth even at low concentrations.