Abstract EANA2025-118

The Moon stands out as a strategic target for manned space missions and in-situ resource utilization (ISRU). Notably, NASA's Artemis program and similar international initiatives aim to establish permanent bases on the Moon and develop life support systems by utilizing local resources. In this context, biotechnological studies on lunar regolith are laying the foundation for sustainable space agriculture and microorganism-based production systems, while regolith simulant experiments conducted on Earth provide critical data for these objectives. Due to their ability to perform photosynthesis and produce secondary metabolites, microalgae are microorganisms with extensive potential in bioregenerative life support systems and space colonization research. Polar microalgae attract attention in biotechnological applications thanks to their adaptive mechanisms against extreme environmental conditions such as low temperature, high ultraviolet radiation, and limited nutrient availability. However, experiments on ISRU are limited due to the technological and economic constraints of manned space missions; therefore, studies often focus on the use of regolith simulants produced on Earth. Lunar regolith is a complex powder mixture with an average particle size of 70 µm, consisting of amorphous and crystalline structured components, mainly composed of plagioclase and pyroxene, and also containing minerals such as olivine and ilmenite. Although cultivating microalgae in lunar regolith simulants offers new opportunities for space farming and life support systems, research in this area remains limited. The aim of this study is to evaluate the potential of lunar regolith simulants as growth media by investigating their effects on the growth of Chlorella sorokiniana EGEMEN.001 microalgae; isolated from Horse Shoe Island, Skua Lake, Antarctica, near Turkiye's Antarctic Research Station. Furthermore, it seeks to assess the suitability of the mineral and chemical structure of lunar regolith for supporting microalgal growth, considering the adaptation capacities of microalgae to extreme conditions. Within the scope of this study, lunar regolith simulants were purchased from NASA and also prepared in the laboratory to resemble the chemical and mineralogical composition of actual regolith collected from different regions of the Moon (Highlands and Mare). The simulants were characterized by various techniques and mixed with distilled water at a specific ratio, then extracted through continuous shaking. The prepared extracts were inoculated with Chlorella sorokiniana EGEMEN.001, and microalgal growth kinetics were monitored. Standard growth medium and distilled water without regolith were used as control groups. The data revealed that lunar regolith simulants significantly influenced microalgal growth, and some simulants demonstrated nutrient potential comparable to the standard medium. The study showed that, under certain conditions, lunar regolith simulants may support microalgal growth and serve as alternative nutrient media to conventional formulations. This finding indicates that in-situ resource utilization might be feasible during space missions, and that microalgae-based bioregenerative life support systems could be established. Future studies may integrate biotechnological strategies such as microbial symbiosis, adaptive evolution, or genetic modification to enhance the bioavailability of regolith. Additionally, optimization of simulant compositions and testing of a broader range of microalgae species are recommended for sustainable microalgae production during long-term space missions.