The Effect of IAA Phytohormone (Indole-3-Acetic Acid) on the Growth, Lipid, Protein, Carbohydrate, and Pigment Content in Euglena sp.

Nowadays, energy consumption is massively increasing in the world. The production of biofuels from microalgae has received considerable attention recently and has the potential to supplant fossil fuels. Recent research focuses on developing the potential of microalgae as an alternative fuel. This research will focus on evaluating the effect of indole-3-acetic acid (IAA) on the growth and metabolite production of Euglena sp. The methods used in this study started with a medium preparation and cultivation using IAA treatment, where the treatment used controlled IAA 5 g/L, IAA 10 g/L, and IAA 15 g/L with three biological repetitions. Optical density (OD) was measured using a spectrophotometer (OD680), biomass was measured using the gravimetry method, lipid was calculated using Bligh and Dyer (1995), the protein was measured using Bradford solution, carbohydrates were measured using phenol sulfuric acid, and pigments were extracted using methanol and measured using a spectrophotometer. According to the findings of this study, IAA 5 g/L can enhance the growth rate. For biomass, the best result was at 10 g/L of IAA (2.216 g/L ± 0.284). Meanwhile, carbohydrates, proteins, and lipids were higher in IAA 15 g/L. Chlorophyll a, b, and total carotenoid were higher in 5 g/L of IAA. The results obtained in this study showed that the IAA hormone increased the growth and metabolite content of Euglena sp.