Fig. 3: Using regolith simulant particles as a mineral source for RPET cell growth.

a, b The minimum levels of nitrogen and phosphorus sources in the minimal medium were determined using either 1 g/L of Lunar (a) or Martian (b) regolith simulant particle as the mineral source. RPET Strain S6 cultivated in the minimal medium without regolith simulant represents the negative control ((−) control), while cultivation in a regular minimal medium represents the positive control ((+) control). In all conditions, mimicked PET hydrolysate was supplied as a carbon source. The variations in the changes of final cell density (OD₆₀₀) were analyzed by using an unpaired two-tailed t-test. The 95% confidence interval for the difference between means of 1x N, 0.5x P w/ Sim, and negative controls for Lunar and Martian regolith simulants are 1.29 to 1.46 and 2.01 to 3.04, respectively. All values represent the mean of triplicate cultures (N = 3), with error bars depicting the standard deviation from that mean. Abbreviations: w/ Sim, with regolith simulant; w/o Sim, without regolith simulant. c Fourier-transform infrared spectroscopy analysis to compare the chemical bond changes on the surface of the regolith particles (left panel, Lunar regolith; right panel, Martian regolith). d Comparing the surface changes of the regolith particles before and after RPET cell growth through Scanning Electron Microscopy analysis (left panel, Lunar regolith; right panel, Martian regolith). Images are representative of N = 3 independent experiments. e XRD analysis to compare the crystalline structure change of the regolith particles before and after RPET cell growth (left panel, Lunar regolith; right panel, Martian regolith). Source data are provided as a Source Data file.